Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC: r257808

Add new AMT serial port PCI ID on Intel Lynx Point chipset

MFC 264981, 264983, 264985:

The freescale imx uart driver works for the whole i.MX family, so rename
the header file to not have "5xx" in the name.

Flesh out imx_uart_init() so that we're not relying on u-boot to init
the hardware (meaning uarts other than the console will work).

Reword a comment block a bit.

MFC 264203, 264204, 264206, 264218:

Tell VM we now have ARM platforms with physically discontiguous memory.

Define the full 1024M of ram on the imx51 and imx53 boards.

Use a more professional uart device description.

MFC 257774, 256760, 262916, 262905, 262918, 262919, 262920, 262921, 262924,
262925, 262929, 262932, 262935, 262940, 262941, 262942, 262948, 262949,
262950

Strip arm/conf/DEFAULTS down to just items that are mandatory for running
the architecture.

Move all the files named foo/common.c to foo/foo_common.c

Initial cut for DTS on the hl201 board.

Add commented out dts for sam9260ek as well as early printf support.

Make clock optional on uart nodes, then back it out ("I don't know what I
was thinking, but it is lame.")

Set the baud rate if it isn't 0

Make at91_soc_id() public.

Properly round at91 resource on unmapping.

Move AT91 AIC related stuff to own file.

Fix another bug in multicast filtering. i.MX uses 6 bits from MSB in
LE CRC32 for the hash value, not the lowest 6 bits in BE CRC32.

Follow r262916 with one more config file that references a renamed common.c

Remove bogus AT91 define that causes compile errors. Most of the defines
for SAM9X are going away soonish anyway (once FDT works), but until
then...

Remove all dregs of a per-thread undefined-exception-mode stack.

Rework the VFP code that handles demand-based save and restore of state.

Always call vfp_discard() on thread death.

When a thread begins life it doesn't own the VFP hardware state on any cpu.

Make undefined exception entry MP-safe.

MFC r261410

Follow r261352 by updating all drivers which are children of simplebus
to check the status property in their probe routines.

MFC r261083, r261092, r261126, r261127, r261128, r261129, r261130, r261131

Add Atmel serial drivers.

uart clock-frequency is a FreeBSD-specific extention. Make it optional and
allow the client uart drivers to decide if a frequency is required.

Remove redundant declaration for uart devclass.
Commit some unrelated, but harmless, FDT ifdefs.

Add at91 NAND support, Fix comment.

Remove obsolete options and fix comments

MFC r256839, r256948, r256950, r257299, r257414, r258057, r259090

Add configuration for the Freescale i.MX53 Quick Start Board.

Add the Raspberry Pi BSC (I2C compliant) controller driver.

Add Radxa Rock board (by radxa.com) support.

Digi-CCWMX53: enable ffec and uart, USB.

Add support for Freescale Vybrid Family VF600

Move and rename dwc otg driver to more generic one as it appears to work
for rk3188 SoC based board too.

MFC r257738, r259202, r258410, r260288, r260292, r260294, r260320, r260323,
r260326, r260327, r260331, r260333, r260340, r260371, r260372, r260373,
r260374, r260375

Add common bus_space tag definition shared for most supported ARMv6/v7 SoCs.
Correct license statements to reflect the fact that these files were all
derived from sys/arm/mv/bus_space.c.

In pmap_unmapdev(), remember the size, and use that as an argument to
kva_free(), or we'd end up always passing it a size of 0

In pmap_mapdev(), first check whether a static mapping exists,

Convert TI static device mapping to use the new arm_devmap_add_entry(),

Use the common armv6 fdt_bus_tag defintion for tegra instead of a local copy.

Eliminate use of fdt_immr_addr(), it's not needed for tegra

Convert lpc from using fdt_immr style to arm_devmap_add_entry() to make
static device mappings.

Retire machine/fdt.h as a header used by MI code, as its function is now
obsolete. This involves the following pieces:
- Remove it entirely on PowerPC, where it is not used by MD code either
- Remove all references to machine/fdt.h in non-architecture-specific code
(aside from uart_cpu_fdt.c, shared by ARM and MIPS, and so is somewhat
non-arch-specific).
- Fix code relying on header pollution from machine/fdt.h includes
- Legacy fdtbus.c (still used on x86 FDT systems) now passes resource
requests to its parent (nexus). This allows x86 FDT devices to allocate
both memory and IO requests and removes the last notionally MI use of
fdtbus_bs_tag.
- On those architectures that retain a machine/fdt.h, unused bits like
FDT_MAP_IRQ and FDT_INTR_MAX have been removed.

Add #include <machine/fdt.h> to a few files that used to get it via pollution

Enable the mv cesa security/crypto device by providing the required property
in the dts source, and adding the right devices to the kernel config.

Remove dev/fdt/fdt_pci.c, which was code specific to Marvell ARM SoCs,
related to setting up static device mappings. Since it was only used by
arm/mv/mv_pci.c, it's now just static functions within that file, plus
one public function that gets called only from arm/mv/mv_machdep.c.

Switch RPi to using arm_devmap_add_entry() to set up static device mapping.

Allow 'no static device mappings' to potentially work.

Don't try to find a static mapping before calling pmap_mapdev(), that logic
is now part of pmap_mapdev() and doesn't need to be duplicated here.

Switch a10 to using arm_devmap_add_entry() to set up static device mapping.

MFC r257170, r257171, r257172, r257240, r257278, r257279, r257280, r257281,
r257282, r257332

Wait for DesignWare UART transfers completion before accessing line control

Enable UART busy detection handling for Armada XP - based board

Enable SATA interface on Armada XP
Run mvs SATA driver on Armada XP instead of old mv_sata

Retire arm_remap_nocache() and the data and constants associated with it.

Remove hard-coded mappings related to Armada XP support

Fix-up DTB for Armada XP registers' base according to the actual settings

Change Armada XP kernel load address to the u-boot's end address

Remove not working and deprecated PJ4Bv6 support

Switch off explicit broadcasting of the TLB flush operations for PJ4B CPU

Add missing ARMv6 CPU functions to ARM Makefile

MFC r258800, r258802, r258805, r258806, r258807, r258851, r258857,
r259199, r259484, r259513, r259514, r259516

The kernel stack guard pages are only below the stack pointer, not above.

Remove unnecessary double-setting of the thread's onfault state in
copyinstr().

Open Firmware mandates that certain cross-references, in particular those
in /chosen, be ihandles. The ePAPR spec makes those cross-reference phandles,
since FDT has no concept of ihandles. Have the OF FDT CI module interpret
queries about ihandles as cross-reference phandles.

Real OF systems have an ihandle under /chosen/stdout, not a phandle. Use
the right type.

Rearchitect platform memory map parsing to make it less
Open Firmware-centric.

Remove fdtbus_bs_tag definition, which is now obsolete. The remainder of
this file is also slated for future demolition.

Return the correct IEEE 1275 code for "nextprop".

Use the common Open Firmware PCI interrupt routing code instead of the
duplicate version in dev/fdt.

Configure interrupt sense based on device tree information.

Simplify the ofw_bus_lookup_imap() API slightly: make it allocate maskbuf
internally instead of requiring the caller to allocate it.

MFC r258259, r258798, r259010

Unify handling of illegal instruction faults between AIM and Book-E.

Make uart_cpu_powerpc work on both FDT and OFW systems.

Fix debug printfs in FPU_EMU to compile on powerpc64 and enable it for
powerpc64.

MFC r257180, r257195, r257196, r257198, r257209, r257295

Add some extra sanity checking and checks to printf format specifiers.

Try even harder to find a console before giving up.

Make devices with registers into the KVA region work reliably.

Turn on VM_KMEM_SIZE_SCALE on 32-bit as well as 64-bit PowerPC.

Return NOKEY instead of 0 if there are no more key presses queued.

MFC r257111, r257144, r257157, r257183

Test UARTs physical address instead of virtual.

Be a bit more flexible in how we find the console from the properties on
/chosen, following the list of allowed console properties in ePAPR. Also
do not require that stdin be defined and equal to stdout: stdin is
nonstandard (for ePAPR) and console in an unexpected place is after all
better than no console.

MFC: r264257, r264327, r264514

Distinguish between the different variants and configurations of Sunix
{MIO,SER}5xxxx chips instead of treating all of them as PUC_PORT_2S.
Among others, this fixes the hang seen when trying to probe the none-
existent second UART on an actually 1-port chip.

Obtained from: NetBSD (BAR layouts)
Sponsored by: Bally Wulff Games & Entertainment GmbH

MFC: r260889, r260890, r260911:

r260911 | imp | 2014-01-20 10:45:36 -0700 (Mon, 20 Jan 2014) | 5 lines

Don't lock in the generic grab just to lock again in the specific grabs.

r260890 | imp | 2014-01-19 12:39:13 -0700 (Sun, 19 Jan 2014) | 11 lines

Introduce grab and ungrab upcalls. When the kernel desires to grab the
console, it calls the grab functions. These functions should turn off
the RX interrupts, and any others that interfere. This makes mountroot
prompt work again. If there's more generalized need other than
prompting, many of these routines should be expanded to do those new
things.

Reviewed by: bde (with reservations)

MFC r259838:
Add another HP iLO serial (console) port, found on Itanium servers.

MFC r259685:

Plumb the cn_grab and cn_ungrab routines down into the uart
clients. Mask RX interrupts while grabbed on the atmel serial
driver. This UART interrupts every character. When interrupts are
enabled at the mountroot> prompt, this means the ISR eats the
characters. Rather than try to create a cooperative buffering system
for the low level kernel console, instead just mask out the ISR. For
NS8250 and decsendents this isn't needed, since interrupts only happen
after 14 or more characters (depending on the fifo settings). Plumb
such that these are optional so there's no change in behavior for all
the other UART clients. ddb worked on this platform because all
interrupts were disabled while it was running, so this problem wasn't
noticed. The mountroot> issue has been around for a very very long
time.

Approved by: re@ (gjb@)

MFC r257556:

Arrange for uart_cpu_fdt's probe() routine to use the same table of compat
strings as uart_bus_fdt's probe().

MFC r257480:

Convert the if/else list of compatible devices to the table-driven
ofw_bus_search_compatible() routine. In addition to converting existing
strings to table entries, also add compat strings for the whole imx family.

MFC r256815:

Calculate the baud rate divisor rather than using a hard-coded value.

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

A final test with unmodified code has shown that a delay of 150ms
is not giving us a 100% success rate. Bump the delay to 200ms as
that seems to do the trick.

Note that during testing the delay was added to uart_bus_attach()
in uart_core.c. While having the delay in a different place can
change the behaviour, it was not expected. Having to bump the
delay with another 50ms could therefore be an indication that
the problem can not be solved with delays.

Reported by: kevlo@
Tested by: kevlo@

Work-around a timing problem with the ITE IT8513E now that the core
calls ns8250_bus_ipend() almost immediately after ns8250_bus_attach().
As it appears, a line break condition is being signalled for almost
all received characters due to this. A delay of 150ms seems enough
to allow the H/W to settle and to avoid the problem.
More analysis is needed, but for now a regression has been addressed.

Reported by: kevlo@
Tested by: kevlo@

Add support for uarts other than the serial console in TI OMAP SoCs.

The TI uart hardware is ns16550-compatible, except that before it can
be used the clocks and power have to be enabled and a non-standard
mode control register has to be set to put the device in uart mode
(as opposed to irDa or other serial protocols). This adds the extra
code in an extension to the standard ns8250 probe routine, and the
rest of the driver is just the standard ns8250 code.

Make the uart ns8250 high-level interface public rather than static.
This makes it easier to implement new drivers which are "mostly ns8250"
but with some small difference such as needing to enable clocks or poke
a non-standard register at probe or attach time.

Use an if/else sequence rather than unrelated if statements, so that a
device compatible with multiple drivers matches the more specific driver
first and doesn't overwrite it later with the more generic. Move the
generic ns16550 to the end of the list.

Check for generic ns16550 after all other types. A device may be compatible
with 16550 but also have a more specific/capable driver earlier in the list.

Allow UART_POLL_FREQ to be set as a kernel option as well as via tunable
(the code was already set up for this, just needs to be in conf/options).

Also, if reporting that polling is being used, report the frequency too.

Set the device description after we call uart_probe(). In uart_probe()
we call device-specific probe functions, which can (and typically will)
set the device description based on low-level device probe information.
In the end we never actually used the device description that we so
carefully maintained in the PCI match table. By setting the device
description after we call uart_probe(), we'll print the more user-
friendly description by default.

Protect against broken hardware. In this particular case, protect against
H/W not de-asserting the interrupt at all. On x86, and because of the
following conditions, this results in a hard hang with interrupts disabled:
1. The uart(4) driver uses a spin lock to protect against concurrent
access to the H/W. Spin locks disable and restore interrupts.
2. Restoring the interrupt on x86 always writes the flags register. Even
if we're restoring the interrupt from disabled to disabled.
3. The x86 CPU has a short window in which interrupts are enabled when the
flags register is written.
4. The uart(4) driver registers a fast interrupt by default.

To catch this case, we first try to clear any pending H/W interrupts and in
particular, before setting up the interrupt. This makes sure the interrupt
is masked on the PIC. The interrupt handler now has a limit set on the
number of iterations it'll go through to clear interrupt conditions. If the
limit is hit, the handler will return FILTER_SCHEDULE_THREAD. The attach
function will check for this return code and avoid setting up the interrupt
and foce polling in that case.

Obtained from: Juniper Networks, Inc.

Teach UART to attach Exynos/s3/s5 class driver.

Submitted by: Ruslan Bukin <br@bsdpad.com>
Reviewed by: gonzo

Add basic support for FDT to i386 & amd64. This change includes:
1. Common headers for fdt.h and ofw_machdep.h under x86/include
with indirections under i386/include and amd64/include.
2. New modinfo for loader provided FDT blob.
3. Common x86_init_fdt() called from hammer_time() on amd64 and
init386() on i386.
4. Split-off FDT specific low-level console functions from FDT
bus methods for the uart(4) driver. The low-level console
logic has been moved to uart_cpu_fdt.c and is used for arm,
mips & powerpc only. The FDT bus methods are shared across
all architectures.
5. Add dev/fdt/fdt_x86.c to hold the fdt_fixup_table[] and the
fdt_pic_table[] arrays. Both are empty right now.

FDT addresses are I/O ports on x86. Since the core FDT code does
not handle different address spaces, adding support for both I/O
ports and memory addresses requires some thought and discussion.
It may be better to use a compile-time option that controls this.

Obtained from: Juniper Networks, Inc.

Fix several typos

PR: kern/176054
Submitted by: Christoph Mallon <christoph.mallon@gmx.de>
MFC after: 3 days

Add Xilinx Zynq ARM/FPGA SoC support to FreeBSD/arm port.

Submitted by: Thomas Skibo <ThomasSkibo (at) sbcglobal.net>
Tested by: wkoszek (ZedBoard)
Reviewed by: wkoszek, freebsd-arm@ (no objections raised)

Add support for Intel C600/X79 Series Chipset KT Controller.

PR: kern/177072
Submitted by: Kurt Lidl <lidl@pix.net>

Build uart_dev_lpc.c on arm only. This fixes pc98 build.

Fix low-level uart drivers that set their fifo sizes in the softc too late.

uart(4) allocates send and receiver buffers in attach() before it calls
the low-level driver's attach routine. Many low-level drivers set the
fifo sizes in their attach routine, which is too late. Other drivers set
them in the probe() routine, so that they're available when uart(4)
allocates buffers. This fixes the ones that were setting the values too
late by moving the code to probe().

Accommodate uart devices with large FIFOs (or DMA buffers which amount
to the same thing) by allocating the uart(4) rx buffer based on the
device's rxfifosz rather than using a hard-coded size of 384 bytes.

The historical 384 byte size is 3 times the largest hard-coded fifo
size in the tree, so use that ratio as a guide and allocate the buffer
as three times rxfifosz, but never smaller than the historical size.

Integrate Efika MX project back to home.

Sponsored by: The FreeBSD Foundation

Add support for A10 uart.
A10 uart is derived from Synopsys DesignWare uart and requires
to read Uart Status Register when IIR_BUSY has detected.
Also this change includes FDT check, where it checks device
specific properties defined in dts and sets the busy_detect variable.
broken_txfifo is also needed to be set in order to make it work for
A10 uart case.

Reviewed by: marcel@
Approved by: gonzo@

- Make pci_ns8250_ids[] const.
- Use DEVMETHOD_END.
- Use NULL instead of 0 for pointers.

MFC after: 1 week

uart: add resume method and enable it for attachments on the most common
x86 buses

Otherwise the uart hardware could be in such a state after the resume
where IER is cleared and thus no interrupts are generated.

This behavior is observed and tested with QEMU, so I am comitting this
change to help with my debugging.
There has been no feedback from users of serial ports on real hardware.

MFC after: 20 days

Add a loader tunable "hw.broken_txfifo" which enables a workaround for a
bug in old versions of QEMU (and Xen, and other places using QEMU code).
On those buggy emulated UARTs, the "TX idle" interrupt gets lost; with
this workaround, we spinwait for the TX to happen and then send ourselves
the interrupt. It's ugly but it works, while minimizing the impact on
the code for the !broken_txfifo case.

MFC after: 2 weeks

Prevent possible usage of uninitialized pbase variable by checking
return value of fdt_get_range

Add support for CIR1000 - Cirrus Logic V34 to the uart driver

Approved by: cperciva (implicit)
MFC after: 1 week

Add support for a few more devices:

PNP0510 and FUJ02E5 for a "Wacom Tablet at FuS Lifebook T"
PNP0502 and PNP0511 for some other generic devices.

PR: kern/173357
Submitted by: Andrey Zakharchenko <avz@jscc.ru>
Approved by: cperciva (implicit)
MFC after: 1 week

Separate interrupts enable/disable logic from setting port parameters.
Otherwise setting baud rate in TTY mode effectively disables TX/RX
interrupts and renders port unusable.

Add PrimeCell UART (PL011) driver

Obtained from: Semihalf

Merging of projects/armv6, part 8

r235162:

Initial LPC32x0 support. Includes DTS file for Embedded Artists EA3250
board.

Peripherals currently supported:
- Serial ports
- Interrupt controller
- Timers
- Ethernet
- USB host
- Framebuffer (in conjunction with SSD1289 LCD controller)
- RTC
- SPI
- GPIO

Submitted by: Jakub Wojciech Klama <jceel@freebsd.org>

Merging of projects/armv6, part 4

r233822:
Remove useless and wrong piece of code in fdt_get_range() which i
overwrites passed phandle_t node. Modify debug printf in fdt_reg_to_rl()
to be consistent (that is, print start and end *virtual* addresses).

r230560:
Handle "ranges;"
Make fdt_reg_to_rl() responsible for mapping the device memory, instead
on just hoping that there's only one simplebus, and using fdt_immr_va as
the base VA.

r230315
Add a function to get the PA from range, instead of (ab)using
fdt_immr_pa, and use it for the UART driver

Complete polled-mode operation by using a callout if the device will be
used in polled-mode. The callout invokes uart_intr, which rearms the timeout.
Implemented for bhyve, but generically useful for e.g. embedded bringup
when the interrupt controller hasn't been setup, or if it's not deemed
worthy to wire an interrupt line from a serial port.

Submitted by: neel
Reviewed by: marcel
Obtained from: NetApp
MFC after: 3 weeks

uart_cpu_amd64.c and uart_cpu_i386.c (under sys/dev/uart) are
identical now that the bus spaces are unified under sys/x86.
Replace them with a single uart_cpu_x86.c.
o delete uart_cpu_i386.c
o move uart_cpu_amd64.c to uart_cpu_x86.c
o update files.amd64 and files.i386 accordingly.

Add PCI Id for the AMT SOL UART on G4x series Intel chipsets.

Submitted by: admin zahost ru
MFC after: 3 days

Add support for the MosChip MCS9904 four serial ports
controller.

PR: 165804
Submitted by: Eugene Grosbein
MFC after: 1 week

Add support for Sony Ericsson GC89 EDGE/Wirelles LAN PC Card

PR: kern/131933
Submitted by: Alex Keda <admin@lissyara.su>
Approved by: jhb
Approved by: cperciva (mentor, blanket for pre-mentorship already-approved commits)
MFC after: 1 week

Add PCI Id for the AMT SOL UART on 5 series Intel chipsets.

MFC after: 1 week

Add support for Intel EG20T serial ports

Use strchr() and strrchr().

It seems strchr() and strrchr() are used more often than index() and
rindex(). Therefore, simply migrate all kernel code to use it.

For the XFS code, remove an empty line to make the code identical to
the code in the Linux kernel.

Actually set the baudrate from the FDT.

Add PCI Id for the Intel AMT serial interface as found on my DQ67OW.

MFC after: 1 week

kern cons: introduce infrastructure for console grabbing by kernel

At the moment grab and ungrab methods of all console drivers are no-ops.

Current intended meaning of the calls is that the kernel takes control of
console input. In the future the semantics may be extended to mean that
the calling thread takes full ownership of the console (e.g. console
output from other threads could be suspended).

Inspired by: bde
MFC after: 2 months

Replace __const by const in all non-contributed source code.

As C1X is close to being released, there is no need to wrap around a
feature that is already part of C90. Most of these files already use
`const' in different placed as well.

Fix OF_finddevice error return value in case of FDT.

According to the open firmware standard, finddevice call has to return
a phandle with value of -1 in case of error.

This commit is to:
- Fix the FDT implementation of this interface (ofw_fdt_finddevice) to
return (phandle_t)-1 in case of error, instead of 0 as it does now.
- Fix up the callers of OF_finddevice() to compare the return value with
-1 instead of 0 to check for errors.
- Since phandle_t is unsigned, the return value of OF_finddevice should
be checked with '== -1' rather than '<= 0' or '> 0', fix up these cases
as well.

Reported by: nwhitehorn

Reviewed by: raj
Approved by: raj, nwhitehorn

Mark MALLOC_DEFINEs static that have no corresponding MALLOC_DECLAREs.

This means that their use is restricted to a single C file.

Disable the TX ready interrupts once we received one, some UART won't clear
the IIR_TXRDY bit upon reading.

Reviewed by: marcel

Follow up to r225203 refining break-to-debugger run-time configuration
improvements:

(1) Implement new model in previously missed at91 UART driver
(2) Move BREAK_TO_DEBUGGER and ALT_BREAK_TO_DEBUGGER from opt_comconsole.h
to opt_kdb.h (spotted by np)
(3) Garbage collect now-unused opt_comconsole.h

MFC after: 3 weeks
Approved by: re (bz)

Attempt to make break-to-debugger and alternative break-to-debugger more
accessible:

(1) Always compile in support for breaking into the debugger if options
KDB is present in the kernel.

(2) Disable both by default, but allow them to be enabled via tunables
and sysctls debug.kdb.break_to_debugger and
debug.kdb.alt_break_to_debugger.

(3) options BREAK_TO_DEBUGGER and options ALT_BREAK_TO_DEBUGGER continue
to behave as before -- only now instead of compiling in
break-to-debugger support, they change the default values of the
above sysctls to enable those features by default. Current kernel
configurations should, therefore, continue to behave as expected.

(4) Migrate alternative break-to-debugger state machine logic out of
individual device drivers into centralised KDB code. This has a
number of upsides, but also one downside: it's now tricky to release
sio spin locks when entering the debugger, so we don't. However,
similar logic does not exist in other device drivers, including uart.

(5) dcons requires some special handling; unlike other console types, it
allows overriding KDB's own debugger selection, so we need a new
interface to KDB to allow that to work.

GENERIC kernels in -CURRENT will now support break-to-debugger as long as
appropriate boot/run-time options are set, which should improve the
debuggability of BETA kernels significantly.

MFC after: 3 weeks
Reviewed by: kib, nwhitehorn
Approved by: re (bz)

Restore binary compatibility for GIO_KEYMAP and PIO_KEYMAP.

Back in 2009 I changed the ABI of the GIO_KEYMAP and PIO_KEYMAP ioctls
to support wide characters. I created a patch to add ABI compatibility
for the old calls, but I didn't get any feedback to that.

It seems now people are upgrading from 8 to 9 they experience this
issue, so add it anyway.

Add device ID for the Davicom 56PDV PCI Modem.

PR: kern/75132
Submitted by: Mike Tancsa @ Sentex (older patch against puc(4))
MFC after: 1 week

Add support for a MosChip PCI express serial port adapter.

MFC after: 1 week

Ignore MCR[6] during the probe to fix a false negative. Bit 6 of the
MCR register on the Sunix Sun1699 chip tends to be set but doesn't
seem to have a function. That is, FreeBSD just works (provided the
correct RCLK is used) regardless.

PR: kern/129663
Diagnostics: Eygene Ryabinkin <rea-fbsd at codelabs.ru>
MFC after: 3 days

Recognize the SAB 82532 found in Fujitsu PRIMEPOWER650 and 900.

Fix typos - remove duplicate "the".

PR: bin/154928
Submitted by: Eitan Adler <lists at eitanadler.com>
MFC after: 3 days

In uart_tty_outwakeup(), check CTS/RTS flow control settings and
prevent sending data when CTS is de-asserted.
In uart_tty_intr(), call uart_tty_outwakeup() when the CTS signal
changed, knowing that uart_tty_outwakeup() will do the right
thing for flow control. This avoids redundant conditionals.

PR: kern/148644
Submitted by: John Wehle <john@feith.com>
MFC after: 3 days

Check the environment for system devices before using the FDT.
This allows overriding the FDT, and allows specifying a debug
port.

Merge amd64 and i386 bus.h and move the resulting header to x86. Replace
the original amd64 and i386 headers with stubs.

Rename (AMD64|I386)_BUS_SPACE_* to X86_BUS_SPACE_* everywhere.

Reviewed by: imp (previous version), jhb
Approved by: kib (mentor)

Fix typos.

PR: bin/148894
Submitted by: olgeni

Eliminate FDT_IMMR_VA define.

This removes platform dependencies from <machine>/fdt.h for the benfit of
portability.

Convert Freescale PowerPC platforms to FDT convention.

The following systems are affected:

- MPC8555CDS
- MPC8572DS

This overhaul covers the following major changes:

- All integrated peripherals drivers for Freescale MPC85XX SoC, which are
currently in the FreeBSD source tree are reworked and adjusted so they
derive config data out of the device tree blob (instead of hard coded /
tabelarized values).

- This includes: LBC, PCI / PCI-Express, I2C, DS1553, OpenPIC, TSEC, SEC,
QUICC, UART, CFI.

- Thanks to the common FDT infrastrucutre (fdtbus, simplebus) we retire
ocpbus(4) driver, which was based on hard-coded config data.

Note that world for these platforms has to be built WITH_FDT.

Reviewed by: imp
Sponsored by: The FreeBSD Foundation

Convert Marvell ARM platforms to FDT convention.

The following systems are involved:

- DB-88F5182
- DB-88F5281
- DB-88F6281
- DB-78100
- SheevaPlug

This overhaul covers the following major changes:

- All integrated peripherals drivers for Marvell ARM SoC, which are
currently in the FreeBSD source tree are reworked and adjusted so they
derive config data out of the device tree blob (instead of hard coded /
tabelarized values).

- Since the common FDT infrastrucutre (fdtbus, simplebus) is used we say
good by to obio / mbus drivers and numerous hard-coded config data.

Note that world needs to be built WITH_FDT for the affected platforms.

Reviewed by: imp
Sponsored by: The FreeBSD Foundation.

FDT (simplebus) compatible attachment for uart(4).

This will be a single uart(4) attachment code shared by all FDT-enabled
platforms.

Reviewed by: imp
Sponsored by: The FreeBSD Foundation

Remove redundant checking of sc_leaving (uart_intr() already handles this).

Approved by: marcel

Add sbbc(4), a driver for the BootBus controller found in Serengeti and
StarCat systems which provides time-of-day services for both as well as
console service for Serengeti, i.e. Sun Fire V1280. While the latter is
described with a device type of serial in the OFW device tree, it isn't
actually an UART. Nevertheless the console service is handled by uart(4)
as this allowed to re-use quite a bit of MD and MI code. Actually, this
idea is stolen from Linux which interfaces the sun4v hypervisor console
with the Linux counterpart of uart(4).

Add PCI ID for MCS9901.

Submitted by: gcooper
PR: kern/144397
MFC after: 1 month

Recognize the NS16552 found in PCIe-based sun4u machines.

Support the tablet in (at least) the Toshiba Portege M200 Tablet PC.
This device only appears on the ACPI bus, so isn't caught by the current
entry for it in the uart(4) ISA attachment.

PR: kern/140172
Reviewed by: jhb, marcel
Approved by: ed (mentor)
MFC after: 2 weeks

Add ID for NetMos NM9820 Serial Port chip, found on CardBus serial adapter.

Add support for the NetMos NM9865 family of Serial/Parallel ports.

Obtained from: NetMos MCS9865 v1.0.0.1 driver
MFC after: 3 days

Remove unneeded includes of <sys/termios.h>.

Fix RTS/CTS flow control, broken by the TTY overhaul. The new TTY
interface is fairly simple WRT dealing with flow control, but
needed 2 new RX buffer functions with "get-char-from-buf" separated
from "advance-buf-pointer" so that the pointer could be advanced
only when ttydisc_rint() succeeded.

MFC after: 1 week

Fix serial console on Apple Xserve G5 by falling back to input-device-1
if input-device is unavailable. The Xserve G5 defaults to using
screen/keyboard for output-device/input-device even if these are not
installed, and then falls back to serial ports at boot time.

Reviewed by: marcel
Hardware from: grehan
Approved by: re (kib)

Move the memory layout definitions and logic from mvreg.h to mvwin.h
so that it isn't exposured unless needed. In particular this means
that it's easier to tune the memory layout based on board details.
While here, remove inclusion of <machine/intr.h> from mvreg.h. This
also contains exposure to SoC specifics in MI drivers, because NIRQ
depends on the SoC.

Last minute TTY API change: remove mutex argument from tty_alloc().

I don't want people to override the mutex when allocating a TTY. It has
to be there, to keep drivers like syscons happy. So I'm creating a
tty_alloc_mutex() which can be used in those cases. tty_alloc_mutex()
should eventually be removed.

The advantage of this approach, is that we can just remove a function,
without breaking the regular API in the future.

Don't use pmap_kextact() when comparing bus handles for Book-E.
We typically wire translation to devices with TLB1 entries and
pmap_kextract() does not know about those and returns 0. This
causes false positives (read: all serial ports suddenly become
the console).

Fix hangs caused by hardware that signals receive errors
(framing, parity, etc), but does not indicate characters
being received. Since no chracters have been received,
ignore the line errors.

PR: 131006
MFC after: 3 days

Add support for 64-bit PowerPC CPUs operating in the 64-bit bridge mode
provided, for example, on the PowerPC 970 (G5), as well as on related CPUs
like the POWER3 and POWER4.

This also adds support for various built-in hardware found on Apple G5
hardware (e.g. the IBM CPC925 northbridge).

Reviewed by: grehan

remove now-redunant cardbus attachment.

Add support for the single-port NetMos NM9835 serial adapter. The puc(4)
entry is a specific entry to override the generic NetMos entry so that
puc(4) will leave this device alone and let uart(4) claim it.

Submitted by: Navdeep Parhar nparhar @ gmail
Reviewed by: marcel
MFC after: 1 week

Added entries for Lava SP-PCI (1 serial + 1 parallel) PCI card. The
card is a multifunction PCI and report itself as two logical devices.

De-hard code UART speed setting for Marvell SOCs when hw.uart.console is not
specified. Instead, let uart(4) fall back to whatever speed firmware has set.

Minor style(9) compliance change.

Cast to uintptr_t before casting to void*. This allows the
QUICC backend to be built on LP64 platforms. This makes it
possible to include the QUICC backend in the kernel module.

PR: 127120

Fix detaching of uart(4) devices.

With our new TTY layer we use a two step device destruction procedure.
The TTY first gets abandoned by the device driver. When the TTY layer
notices all threads have left the TTY layer, it deallocates the TTY.

This means that the device unit number should not be reused before a
callback from the TTY layer to the device driver has been made. newbus
doesn't seem to support this concept (yet), so right now just add a
destructor with a big comment in it. It's not ideal, but at least it's
better than panicing.

Reported by: rnoland

Introduce basic support for Marvell families of system-on-chip ARM devices:

* Orion
- 88F5181
- 88F5182
- 88F5281

* Kirkwood
- 88F6281

* Discovery
- MV78100

The above families of SOCs are built around CPU cores compliant with ARMv5TE
instruction set architecture definition. They share a number of integrated
peripherals. This commit brings support for the following basic elements:

* GPIO
* Interrupt controller
* L1, L2 cache
* Timers, watchdog, RTC
* TWSI (I2C)
* UART

Other peripherals drivers will be introduced separately.

Reviewed by: imp, marcel, stass (Thanks guys!)
Obtained from: Marvell, Semihalf

Use bus_space_compare() rather than i386_memio_compare() directly.

Add the 2nd CCU and PnP devices support on pc98.

Reviewed by: imp
Obtained from: //depot/projects/uart with some fixes

Integrate the new MPSAFE TTY layer to the FreeBSD operating system.

The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

The old TTY layer has a driver model that is not abstract enough to
make it friendly to use. A good example is the output path, where the
device drivers directly access the output buffers. This means that an
in-kernel PPP implementation must always convert network buffers into
TTY buffers.

If a PPP implementation would be built on top of the new TTY layer
(still needs a hooks layer, though), it would allow the PPP
implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

With the old TTY layer, it isn't entirely safe to destroy TTY's from
the system. This implementation has a two-step destructing design,
where the driver first abandons the TTY. After all threads have left
the TTY, the TTY layer calls a routine in the driver, which can be
used to free resources (unit numbers, etc).

The pts(4) driver also implements this feature, which means
posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

One of the major improvements is the per-TTY mutex, which is expected
to improve scalability when compared to the old Giant locking.
Another change is the unbuffered copying to userspace, which is both
used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from: //depot/projects/mpsafetty/...
Approved by: philip (ex-mentor)
Discussed: on the lists, at BSDCan, at the DevSummit
Sponsored by: Snow B.V., the Netherlands
dcons(4) fixed by: kan

The XScale PXA255 has three generally ns16x50 compatible UARTs. One of the
variations from normal 16x50 behaviour however is the the use of a normally
unused bit of IER to control RX timeout interrupts independently of the
generally used RXRDY bit. If this bit is not enabled, we only ever get
interrupts when the FIFO is full, never before. This is not very useful when
the UART is being used as a console.

In order to support this without causing potential problems on more "normal"
16x50 variants, this change introduces two hints for the uart device, ier_mask
and ier_rxbits. These can be used to override which bits get set and cleared
when we're enabling and disabling RX interrupts.

Reviewed by: marcel

Expand kdb_alt_break a little, most commonly used with the option
ALT_BREAK_TO_DEBUGGER. In addition to "Enter ~ ctrl-B" (to enter the
debugger), there is now "Enter ~ ctrl-P" (force panic) and
"Enter ~ ctrl-R" (request clean reboot, ala ctrl-alt-del on syscons).

We've used variations of this at work. The force panic sequence is
best used with KDB_UNATTENDED for when you just want it to dump and
get on with it.

The reboot request is a safer way of getting into single user than
a power cycle. eg: you've hosed the ability to log in (pam, rtld, etc).
It gives init the reboot signal, which causes an orderly reboot.

I've taken my best guess at what the !x86 and non-sio code changes
should be.

This also makes sio release its spinlock before calling KDB/DDB.

add device hints to control the rx FIFO interrupt level on 16550A parts

PR: kern/121421
Submitted by: UEMURA Tetsuya
Reviewed by: marcel
MFC after: 2 weeks

Support for Freescale QUad Integrated Communications Controller.

The QUICC engine is found on various Freescale parts including MPC85xx, and
provides multiple generic time-division serial channel resources, which are in
turn muxed/demuxed by the Serial Communications Controller (SCC).

Along with core QUICC/SCC functionality a uart(4)-compliant device driver is
provided which allows for serial ports over QUICC/SCC.

Approved by: cognet (mentor)
Obtained from: Juniper
MFp4: e500

Initial support for Freescale PowerQUICC III MPC85xx system-on-chip family.

The PQ3 is a high performance integrated communications processing system
based on the e500 core, which is an embedded RISC processor that implements
the 32-bit Book E definition of the PowerPC architecture. For details refer
to: http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MPC8555E

This port was tested and successfully run on the following members of the PQ3
family: MPC8533, MPC8541, MPC8548, MPC8555.

The following major integrated peripherals are supported:

* On-chip peripherals bus
* OpenPIC interrupt controller
* UART
* Ethernet (TSEC)
* Host/PCI bridge
* QUICC engine (SCC functionality)

This commit brings the main functionality and will be followed by individual
drivers that are logically separate from this base.

Approved by: cognet (mentor)
Obtained from: Juniper, Semihalf
MFp4: e500

Add a new 'why' argument to kdb_enter(), and a set of constants to use
for that argument. This will allow DDB to detect the broad category of
reason why the debugger has been entered, which it can use for the
purposes of deciding which DDB script to run.

Assign approximate why values to all current consumers of the
kdb_enter() interface.

Redefine bus_space_tag_t on PowerPC from a 32-bit integral to
a pointer to struct bus_space. The structure contains function
pointers that do the actual bus space access.

The reason for this change is that previously all bus space
accesses were little endian (i.e. had an explicit byte-swap
for multi-byte accesses), because all busses on Macs are little
endian.
The upcoming support for Book E, and in particular the E500
core, requires support for big-endian busses because all
embedded peripherals are in the native byte-order.

With this change, there's no distinction between I/O port
space and memory mapped I/O. PowerPC doesn't have I/O port
space. Busses assign tags based on the byte-order only.
For that purpose, two global structures exist (bs_be_tag and
bs_le_tag), of which the address can be taken to get a valid
tag.

Obtained from: Juniper, Semihalf

The HP Diva RMP3 uses BAR 0x14.

Fix bugs in the Sun -> AT keycode translation table which caused the
Props key to act as Again and the Paste and Copy keys to be inverted.

Add PCI IDs for the HP RMP3 serial port. This is often used as
the serial console.

MFC after: 1 week

Don't use a time-limiting loop that's defined in terms of the baudrate
in the putc() method. Likewise, in the getc() method, don't check for
received characters with an interval defined in terms of the baudrate.
In both cases it works equally well to implement a fixed delay. More
importantly, it avoids calculating a delay that's roughly 1/10th the
time it takes to send/receive a character. The calculation is costly
and happens for every character sent or received, affecting low-level
console or debug port performance significantly. Secondly, when the
RCLK is not available or unreliable, the delays could disrupt normal
operation.

The fixed delay is 1/10th the time it takes to send a character at
230400 bps.

Don't expose the uart_ops structure directly, but instead have
it obtained through the uart_class structure. This allows us
to declare the uart_class structure as weak and as such allows
us to reference it even when it's not compiled-in.
It also allows is to get the uart_ops structure by name, which
makes it possible to implement the dt tag handling in uart_getenv().
The side-effect of all this is that we're using the uart_class
structure more consistently which means that we now also have
access to the size of the bus space block needed by the hardware
when we map the bus space, eliminating any hardcoding.

For embedded UARTs compatible with the ns8250 family it is possible
that the driver clock is identical to the processor or bus clock.
This is the case for the PowerQUICC processor. When the clock is
high enough, overflows happen in the calculation of the time it
takes to send 1/10 of a character, used in delay loops. Fix the
overflows so as to fix bugs in the delay loops that can cause either
insufficient delays or excessive delays.

When we match UARTs found during bus-enumeration with UARTs used for
system devices (i.e. console, debug port or keyboard), don't stop
after the first match. Find them all and keep track of the last.
The reason for this change is that the low-level console is always
added to the list of system devices first, with other devices added
later. Since new devices are added to the list at the head, we have
the console always at the end. When a debug port is using the same
UART as the console, we would previously mark the "newbus" UART as
a debug port instead of as a console. This would later result in a
panic because no "newbus" device was associated with the console.
By matching all possible system devices we would mark the "newbus"
UART as a console and not as a debug port.
While it is arguably better to be able to mark a "newbus" UART as
both console and debug port, this fix is lightweight and allows
a single UART to be used as the console as well as a debug port
with only the aesthetic bug of not telling the user about it also
being a debug port.

Now that we match all possible system devices, update the rclk of
the system devices with the rclk that was obtained through the
bus attachment. It is generally true that clock information is
more reliable when obtained from the parent bus than by means of
some hardcoded or assumed value used early in the boot. This by
virtue of having more context information.

MFC after: 1 month

o break newbus api: add a new argument of type driver_filter_t to
bus_setup_intr()

o add an int return code to all fast handlers

o retire INTR_FAST/IH_FAST

For more info: http://docs.freebsd.org/cgi/getmsg.cgi?fetch=465712+0+current/freebsd-current

Reviewed by: many
Approved by: re@

- Add a uart_rxready() and corresponding device-specific implementations
that can be used to check whether receive data is ready, i.e. whether
the subsequent call of uart_poll() should return a char, and unlike
uart_poll() doesn't actually receive data.
- Remove the device-specific implementations of uart_poll() and implement
uart_poll() in terms of uart_getc() and the newly added uart_rxready()
in order to minimize code duplication.
- In sunkbd(4) take advantage of uart_rxready() and use it to implement
the polled mode part of sunkbd_check() so we don't need to buffer a
potentially read char in the softc.
- Fix some mis-indentation in sunkbd_read_char().

Discussed with: marcel

- In sunkbd_probe_keyboard() don't bother to determine the keyboard layout
as we have no use for that info. Instead let this function return the
keyboard ID and verify at its invocation in sunkbd_configure() that we're
talking to a Sun type 4/5/6 keyboard, i.e. a keyboard supported by this
driver.
- Add an option SUNKBD_EMULATE_ATKBD whose code is based on the respective
code in ukbd(4) and like UKBD_EMULATE_ATSCANCODE causes this driver to
emit AT keyboard/KB_101 compatible scan codes in K_RAW mode as assumed by
kbdmux(4). Unlike UKBD_EMULATE_ATSCANCODE, SUNKBD_EMULATE_ATKBD also
triggers the use of AT keyboard maps and thus allows to use the map files
in share/syscons/keymaps with this driver at the cost of an additional
translation (in ukbd(4) this just is the way of operation).
- Implement an option SUNKBD_DFLT_KEYMAP, which like the equivalent options
of the other keyboard drivers allows to specify the default in-kernel
keyboard map. For obvious reasons this made to only work when also using
SUNKBD_EMULATE_ATKBD.
- Implement sunkbd_check(), sunkbd_check_char() and sunkbd_clear_state(),
which are also required for interoperability with kbdmux(4).
- Implement K_CODE mode and FreeBSD keypad compose.
- As a minor hack define KBD_DFLT_KEYMAP also in the !SUNKBD_EMULATE_ATKBD
case so we can obtain fkey_tab from <dev/kbd/kbdtables.h> rather than
having to duplicate it and #ifdef some more code.
- Don't use the TX-buffer for writing the two command bytes for setting the
keyboard LEDs as this consequently requires a hardware FIFO that is at
least two bytes in depth, which the NMOS-variant of the Zilog SCCs doesn't
have. Thus use an inlined version of uart_putc() to consecutively write
the command bytes (a cleaner approach would be to do this via the soft
interrupt handler but that variant wouldn't work while in ddb(4)). [1]
- Fix some minor style(9) bugs.

PR: 90316 [1]
Reviewed by: marcel [1]

Fix our ioctl(2) implementation when the argument is "int". New
ioctls passing integer arguments should use the _IOWINT() macro.
This fixes a lot of ioctl's not working on sparc64, most notable
being keyboard/syscons ioctls.

Full ABI compatibility is provided, with the bonus of fixing the
handling of old ioctls on sparc64.

Reviewed by: bde (with contributions)
Tested by: emax, marius
MFC after: 1 week

Do not try to call keyboard callback unless keyboard is active and busy.
This should fix 'kbdcontrol -K < /dev/console' panic on sparc64 with sunkbd(4).

PR: sparc64/96798
MFC after: 1 week

Properly propagate overrun conditions to the TTY layer.

MFC after: 3 days

On PowerPC the clock for the BRG comes from RTxC, not PCLK. Add a
quick hack to deal with this. We may need to formalize this better
and have this information come from the bus attachments.

Implement UART_IOCTL_BAUD for the Z8530. This allows a serial console
on PowerPC use the current setting of the hardware and not second
guess what the OFW does on various machines.

Implement uart_cpu_eqres() and uart_cpu_getdev(). This allows
FreeBSD to use a serial console, as per the OFW settings.

Convert to new console api

Eliminate gdb_checkc member from GDB_DBGPORT(), it is never used.

Use polling behaviour for gdb_getc() where convenient, this edges us
closer to the console code.

Remove definitions of uart_[gs]etdreg. They are not used anymore and
were in fact wrong.

The lcr variable in ns8250_probe is now unused. Remove it.

Missed by: benno

Allow uart(4)'s ns8250 driver to work with devices whose regshift is > 0.

- Rename REG_DL to REG_DLL and REG_DLH.
- Always treat DLL and DLH as two separate 8-bit registers instead of one
16-bit register.

Additionally, remove the probe for the high 4 bits of IER being 0 and don't
assume we can always read/write 0 to/from those bits.

These changes allow uart(4) to drive the UARTs on the Intel XScale PXA255.

Reviewed by: marcel

o A divisor of 0 is perfectly valid. Reserve -1 for an invalid
divisor. This allows us to set the line speed to the maximum
of 1/4 of the device clock.
o Disable the baudrate generator before programming the line
settings, including baudrate, and enable it afterwards.

First pass at removing Alpha kernel support.

Rewrite of puc(4). Significant changes are:
o Properly use rman(9) to manage resources. This eliminates the
need to puc-specific hacks to rman. It also allows devinfo(8)
to be used to find out the specific assignment of resources to
serial/parallel ports.
o Compress the PCI device "database" by optimizing for the common
case and to use a procedural interface to handle the exceptions.
The procedural interface also generalizes the need to setup the
hardware (program chipsets, program clock frequencies).
o Eliminate the need for PUC_FASTINTR. Serdev devices are fast by
default and non-serdev devices are handled by the bus.
o Use the serdev I/F to collect interrupt status and to handle
interrupts across ports in priority order.
o Sync the PCI device configuration to include devices found in
NetBSD and not yet merged to FreeBSD.
o Add support for Quatech 2, 4 and 8 port UARTs.
o Add support for a couple dozen Timedia serial cards as found
in Linux.

Implement the ipend() method of the serdev I/F.

o Add 5 Timedia single port serial cards.
o While here, break long lines.

Use 115200 and not 9600 as the initial baudrate. This speeds up
detection of the FIFO size. Especially for large FIFOs.

o Add 2 HP Diva single port UARTs.

o Add 2 NEC cards
o Add 2 Dell cards
o Add Quatech card
o Add support for non-standard rclk values.
o Update descriptions to match PCI id database.

MFp4: Calculate the divisor before setting the DLAB bit. This
prevents that there's a control flow that leaves the DLAB
bit set.

In z8530_divisor() return 0 if the calculated divisor is less than 0.
This happens when the baudrate is too high for the given RCLK.

Remove unused variable 'error'. Forgotten in previous commit.

Don't claim a SAB82532. We have scc(4) for that.

Eliminate the sc_hasfifo flag from the softc. It was only used by
the NS8250 class driver. The UART has FIFOs if sc_rxfifosz>1, so
test for that instead.
While here properly initialize sc_rxfifosz and sc_txfifosz in the
case the UART doesn't have FIFOs.

Don't hold the hardware mutex across getc(). It can wait indefinitely
for a character to be received. Instead let getc() do any necesary
locking.

Allow uart(4) to be built on PowerPC.

Add support for scc(4).

Add scc(4), a driver for serial communications controllers. These
controllers typically have multiple channels and support a number
of serial communications protocols. The scc(4) driver is itself
an umbrella driver that delegates the control over each channel
and mode to a subordinate driver (like uart(4)).
The scc(4) driver supports the Siemens SAB 82532 and the Zilog
Z8530 and replaces puc(4) for these devices.

Don't open if we're going away.

Replace our local UART_SIGMASK_* with the global SER_MASK_*.

When we probe a SAB82532, return BUS_PROBE_GENERIC. This allows puc(4)
or scc(4) to grab the device by default. In fact, we probably shouldn't
even claim the device at all...

MFp4:
Stop using our local UART_IPEND_* and instead use the global SER_INT_*
as defined in <sys/serial.h>.

- Use bus_setup_intr() and bus_teardown_intr() to register device driver
interrupt handlers rather than BUS_SETUP_INTR() and BUS_TEARDOWN_INTR().
Uses of the BUS_*() versions in the implementation of foo_intr methods
in bus drivers were not changed. Mostly this just means that some
drivers might start printing diagnostic messages like [FAST] when
appropriate as well as honoring mpsafenet=0.
- Fix two more of the ppbus drivers' identify routines to function
correctly in the mythical case of a machine with more than one ppbus.

- Add support for using LOM (Lights Out Management) and RSC (Remote System
Control) devices as console. These are microcontrollers which are either
on-board or part of an add-on card and provide terminal server, remote
power switch and monitoring functionality. For console usage these are
connected to the rest of the system via a SCC or an UART. This commit adds
support for the following variants (corresponds to what 'input-device' and
'output-device' have to be set to):
rsc found on-board in E250 and supposedly some Netra, connected
via a SAB82532, com. parameters can be determined via OFW
rsc-console RSC card found in E280R, Fire V4x0, Fire V8x0, connected
via a NS16550, hardwired to 115200 8N1
lom-console LOMlite2 card found in Netra 20/T4, connected via a NS16550,
hardwired to 9600 8N1

- Add my copyright to uart_cpu_sparc64.c as I've rewritten about one third
of that file over time.

Tested on: E250, E280R
Thanks to: dwhite@ for providing access to an E280R
OK'ed by: marcel
MFC after: 1 week

Make uart_getenv() not be ns8250 dependent. This will allow, in the future,
compilation of kernels without ns8250 support but using the uart framework.
These kernels will be for machines where size matters more, so including code
that can never be executed is undesriable...

In uart_bus_probe() return BUS_PROBE_DEFAULT when the probe is
successful.

o Style(9) nits
o Fix typo in comment
o s/-100/BUS_PROBE_GENERIC/
o s/err/error/ for consistency
o Remove non-applicable comment
o Allow uart_bus_probe() to return the predefined BUS_PROBE_*
contants. In this case: explicitly test for error > 0.

Allow uart_bus_probe() to return the predefined BUS_PROBE_*
constants. In this case: just return what uart_bus_probe()
returns.

- Use swi_remove() to teardown swi handlers rather than
intr_event_remove_handler().
- Remove tty: prefix from a couple of swi handler names.

Remove PCI IDs for multiport cards:
o Oxford Semiconductor PCI Dual Port Serial
o Netmos Nm9845 PCI Bridge with Dual UART

Add PCI IDs for single-port cards:
o Various SIIG Cyber Serial
o Oxford Semiconductor OXCB950 UART

Update description as per puc(4).

Reorganize the interrupt handling code a bit to make a few things cleaner
and increase flexibility to allow various different approaches to be tried
in the future.
- Split struct ithd up into two pieces. struct intr_event holds the list
of interrupt handlers associated with interrupt sources.
struct intr_thread contains the data relative to an interrupt thread.
Currently we still provide a 1:1 relationship of events to threads
with the exception that events only have an associated thread if there
is at least one threaded interrupt handler attached to the event. This
means that on x86 we no longer have 4 bazillion interrupt threads with
no handlers. It also means that interrupt events with only INTR_FAST
handlers no longer have an associated thread either.
- Renamed struct intrhand to struct intr_handler to follow the struct
intr_foo naming convention. This did require renaming the powerpc
MD struct intr_handler to struct ppc_intr_handler.
- INTR_FAST no longer implies INTR_EXCL on all architectures except for
powerpc. This means that multiple INTR_FAST handlers can attach to the
same interrupt and that INTR_FAST and non-INTR_FAST handlers can attach
to the same interrupt. Sharing INTR_FAST handlers may not always be
desirable, but having sio(4) and uhci(4) fight over an IRQ isn't fun
either. Drivers can always still use INTR_EXCL to ask for an interrupt
exclusively. The way this sharing works is that when an interrupt
comes in, all the INTR_FAST handlers are executed first, and if any
threaded handlers exist, the interrupt thread is scheduled afterwards.
This type of layout also makes it possible to investigate using interrupt
filters ala OS X where the filter determines whether or not its companion
threaded handler should run.
- Aside from the INTR_FAST changes above, the impact on MD interrupt code
is mostly just 's/ithread/intr_event/'.
- A new MI ddb command 'show intrs' walks the list of interrupt events
dumping their state. It also has a '/v' verbose switch which dumps
info about all of the handlers attached to each event.
- We currently don't destroy an interrupt thread when the last threaded
handler is removed because it would suck for things like ppbus(8)'s
braindead behavior. The code is present, though, it is just under
#if 0 for now.
- Move the code to actually execute the threaded handlers for an interrrupt
event into a separate function so that ithread_loop() becomes more
readable. Previously this code was all in the middle of ithread_loop()
and indented halfway across the screen.
- Made struct intr_thread private to kern_intr.c and replaced td_ithd
with a thread private flag TDP_ITHREAD.
- In statclock, check curthread against idlethread directly rather than
curthread's proc against idlethread's proc. (Not really related to intr
changes)

Tested on: alpha, amd64, i386, sparc64
Tested on: arm, ia64 (older version of patch by cognet and marcel)

Eliminate two unused arguments to ttycreate().

Remove OLDCARD shims

- Change the code that determines whether to use a serial console and
which serial device to use in that case respectively to not rely on
the OFW names of the input/output and stdin/stdout devices. Instead
check whether input and output refers to the same device and is of
type serial (uart(4) was already doing this) and for the fallback
to a serial console in case a keyboard is the selected input device
but unplugged do the same for stdin and stdout in case the input
device is nonexistent (PS/2 and USB keyboards) or has a 'keyboard'
property (RS232 keyboards). Additionally also check whether the OFW
did a fallback to a serial console in the same way in case the
output device is nonexistent. While at it save on some variables
and for sys/boot/sparc64/loader/metadata.c move the code in question
to a new function md_bootserial() so it can be kept in sync with
uart_cpu_getdev_console() more easily.
This fixes selecting a serial console and the appropriate device
when using a device path for the 'input-device' and 'output-device'
OFW environment variables instead of an alias for the serial device
to use or when using a screen alias that additionally denotes a
video mode (like e.g. 'screen:r1024x768x60') but no keyboard is
plugged in (amongst others). It also makes the code select a serial
console in case the OFW did the same due to a misconfiguration like
both 'input-device' and 'output-device' set to 'keyboard' or to a
nonexisting device (whether the OFW does a fallback to a serial
console in case of a misconfiguration or one ends up with just no
console at all highly depends on the OBP version however).
- Reduce the size of buffers that only ever need to hold the string
'serial' accordingly. Double the size of buffers that may need to
hold a device path as e.g. '/pci@8,700000/ebus@5/serial@1,400000:a'
exceeds 32 chars.
- Remove the package handle of the '/options' node from the argument
list of uart_cpu_getdev_dbgport() as it's unused there and future
use is also unlikely.

MFC after: 1 week

Recognize the SAB82532 in USIII machines.

Some chipset drivers redefine the busspace_isa_{io|mem} tags. This
not only means that it's possible (though unlikely) that we hand out
differing tags for the same bus space, it also means that the tags
we handed out are not used during bus enumeration. Both affect our
ability to compare tags. Fix the first by initializing our tags only
once. Fix the second by testing if one of the tags to compare is our
tag and the other is a busspace_isa_{io|mem} tag and declare them
equal if so.

This fixes using uart(4) as the serial console on a ds10. That is,
the low-level console worked, but we could not match the resources
to one of the UARTs found during bus enumeration, which prevented
uart(4) from becoming the console in single- or multi-user mode.

Approved by: re (kensmith)
MFC after: 2 days
Thanks to: all involved in getting a ds10 to me; directly or indirectly.
Special thanks to: Dave Knight, ISC (for not scratching my Porsche :-)

Replace the band-aid for allowing to call sunkbd_configure() multiple
times which was added in the last revision with what should be a proper
solution as long as keyboards that were pluggged in after the kernel
has fully booted aren't supported. I.e. when sunkbd_configure() is
called for the high-level console probe make sure that the keyboard is
both successfully configured (i.e. also probed) and attached. The band-
aid left the possibility to attach the keyboard device to the high-level
console without attaching the keyboard device itself when the keyboard
is plugged in after uart(4) attached but before syscons(4) does.

On AXi and AXmp boards the NS16550 (used to connect keyboard and mouse)
share their IRQ lines with the i8042. Any IRQ activity (typically during
attach) on the NS16550 used to connect the keyboard when actually the
PS/2 keyboard is selected in OFW causes interaction with the OBP i8042
driver resulting in a hang (and vice versa). As RS232 keyboards and mice
obviously aren't meant to be used in parallel with PS/2 ones on these
boards don't attach to these NS16550 in case the RS232 keyboard isn't
selected in order to prevent such hangs.

Ok'ed by: marcel

Change the semantics of uart_cpu_getdev_keyboard() to only match SCCs/
UARTs used to connect keyboards and not also PS/2 keyboards and only
return their package handle in case the keyboard is the preferred one
according to the OFW but otherwise still regardless of whether the
keyboard is used for stdin or not. This is simply achieved by looking
at the 'keyboard' alias and returning the corresponding package handle
in case it refers to a SCC/UART. This is change is done in order to
give the keyboard which the OFW or the user selected in OFW on boards
that support additional types of keyboards besides the RS232 ones also
preference in FreeBSD. It will be also used to determine on Sun AXi and
Sun AXmp boards whether a PS/2 or a RS232 is to be used as these are
sort of mutual exclusive there (see upcoming commit to uart_bus_ebus.c).
Note that Tatung AXi boards have the same issue but the former code
happened to already give the PS/2 keyboard preference by not identifying
the respective UART as keyboard system device there because the PS/2
keyboard node precedes the keyboard UART one in the OFW device tree of
these boards (which isn't the case for the Sun AXi).

Ok'ed by: marcel

- Sprinkle some KBD_IS_* and KBD_*_DONE macros in sunkbd_configure() as
a band-aid allowing to call this function savely multiple times, e.g.
during sckbdprobe() and sc_probe_unit(). Otherwise calling it a second
time results in a non-working keyboard. This needs a lot of more work
to actually do the right thing and work like expected.
- Let sunkbd_configure() return the number of the found keyboards, i.e.
1 in case probing succeeds, as it's expected. The return values of the
keyboard configure functions however currently aren't checked so this
doesn't make a difference at the moment.
- Use FBSDID.

In uart_cnprobe(), fill in the cn_name field of the consdev structure.
The core console code checks this field when a console is added and
emits a warning if it's empty. In practice the warning is harmless for
uart(4), because the cn_name is filled in as soon as the device name is
known; which is when the device is enumerated.
To avoid the warning, to avoid possible complications caused by emitting
the warning without there (possibly) being a console selected yet and to
avoid complications when the UART isn't found during bus enumeration, we
just preset the cn_name field here to the name of the driver.

Make the Z8530 more reliable as low-level console by making use of the
fact that access to RR0 does not need a prior write to the register
index because the index always reverts to 0 after the indexed register
has been accessed.

Typically when a RR or WR is to accessed, one programs the index (which
is a write to the control register), followed by a read or write to the
actual indexed register (a read pr write to the same control register).
When this non-atomic sequence is interrupted after having written the
index and low-level console I/O is done in that situation, the write to
program the index will actually write to the indexed register and nuke
state. This almost always yields a wedge.

By not programming the index register and instead just reading from RR0,
the worst case scenario is non-fatal. For if we don't actually read from
RR0 but some other register we get an invalid status, which may lead us
to conclude that the transit data register is empty when it's not or that
the receive data register contains data when it doesn't. Hence, we may
lose an output character or get a sporadic input character, but given
the situation this is a non-issue.

Full serialization is not possible due to the fact that this code needs
to work from DDB and before mutex initialization has happened.

In collaboration with: kris@, marius@
Tested by: kris@
MFC after: 1 day
X-MFC: 5.4-RELEASE candidate

In uart_cpu_getdev_console() when determinig whether we should use
a serial console anyway because input-device is set to keyboard and
output-device is set to screen but no keyboard is plugged in don't
assume that a device node for the input-device alias exists. While
this is true for RS232 keyboards (the node of the SCC and UART
respectively which controls the keyboard doesn't disappear when no
keyboard is plugged in) this assumption breaks for USB keyboards.
It's most likely also not true for PS/2 keyboards but OFW doesn't
reliably switch to a serial console when the potential keyboard is
a PS/2 one which isn't plugged in so this couldn't be verified
properly.

Reported by: Will Andrews <will@csociety.org>, obrien
MFC after: 1 week

- Allocate the interrupt resource as RF_SHAREABLE allowing uart(4) to work
with shared IRQs in case the bus code, MD interrupt code, etc. permits.
Together with sys/sparc64/sparc64/intr_machdep.c rev. 1.21 this fixes
an endless loop in uart_intr() when using the second NS16550 on the ISA
bus of sparc64 machines.
- Destroy the hardware mutex on detach and in case attaching fails.

Approved by: marcel

- Re-write OF_decode_addr() with a bus-neutral approach, adding support
for nodes hanging off of Central (untested), FireHose (untested) and
PCI (tested) busses.
- Add an additional parameter to OF_decode_addr() which specifies the
index of the register bank to decode.

These should allow to eventually add support for the Z8530 hanging off of
FireHose to uart(4) and to write support for PCI-based graphics adapters.

Suggested by: tmm (back in '03)

Add the keyboard system device before we probe for the keyboard.
The presence or absence of a keyboard does not change whether an
UART is designed as a keyboard port or not and thus whether we
can use the port as a TTY or not.
We now call sunkbd_attach() even when we didn't previously find
a keyboard. Emit a useful message stating that no keyboard was
found, but don't do anything else.

MFC after: 5 days

Fix a logic bug that caused DSR to never be deasserted.

MFC after: 5 days

o Fix the various interrupt related problems caused by reverse
engineering the pending interrupt sources from the current
state of the controller. For channel A we can always read the
interrupt pending register (RR3). For channel B we can read
the interrupt vector register (RR2) because it contains the
modified vector and thus includes the interrupt source.
Since we currently need puc(4) for the Z8530, we know that
the interrupt handler for both channels will be called and
thus that RR3 will always be read at least once, even if ch A
has no pending interrupt.
NOTE: The modified interrupt vector has no value that represent
a lack of pending interrupt for channel B. That is, the
value read when no interrupts are pending is the same as the
value for the special receive condition. Fortunately, we don't
actually have to depend on that interrupt source. This does
mean that we need to properly handle the overflow condition,
when we read received character from the chip.
o The DSR signal is represented by the SYNC bit in the external
status register (RR0). We now properly track DSR.
o It's save to enable the external/status interrupt source. We
now get interrupts when line signals (DSR, DCD or CTS) change.

Problems fixes:
o interrupt storms.
o blocked open(2).
o lack of (hardware) flow control.
o unable to report DSR.

MFC after: 5 days

Start each of the license/copyright comments with /*-, minor shuffle of lines

Don't obtain the HCDP address directly from the bootinfo structure.
Use a function to keep the details at arms length from uart(4).

- Don't blindly use the return value of uart_cpu_channel() to calculate
the address of a channel on a SCC, it returns 0 on failure. [1]
- Hardcode channel 1 for the keyboard on Z8530, the information present
in the Open Firmware device tree doesn't allow to determine this via
uart_cpu_channel(). This makes the keyboard (if one backs out rev. 1.5
of sys/dev/puc/puc_sbus.c and has both keyboard and mouse plugged in to
avoid the hang that revision works around) and consequently syscons(4)
on Ultra 2 work. There's a problem with the keyboard LEDs similar to
the one on Ultra 60 (LEDs don't get lit under X) though, instead of
lighting just a specific single one all get lit and can't be turned off
again. [1]
- Add comments about what uart_cpu_channel() and uart_cpu_getdev_keyboard()
do and their constraints.
- Improve the comments about what uart_cpu_getdev_[console,dbgport]() do,
they don't return an address (as in bus) but an Open Firmware package
handle.

Reviewed by: marcel (modulo the comments) [1]

uart_i8251_ops is gone.

o Support for the i8251 wasn't there. Remove the files.
o Remove the headers with IC register definitions. The headers are
now taken from sys/dev/ic

Include the header with the register definitions from sys/dev/ic. They
are shared now.

Include the common <dev/ic/ns16550.h> instead of the private
<dev/uart_dev_ns8250.h>. The latter can be removed now.

Remove the whole uart_cpu_identify() stuff again. Now that it's no longer
used on sparc64 they are only stubs on all architectures and it doesn't
look like if we would need it in the near future again.

Ok'ed by: marcel

o sparc64/isa/isa.c:
- The claim in the commit log of rev. 1.11 of dev/uart/uart_cpu_sparc64.c
etc. that UARTs are the only relevant ISA devices on sparc64 turned out
to be false. While there are sparc64 models where UARTs are the only
devices on the ISA bus there are in fact also low-cost models where all
devices traditionally found on the EBus are hooked up to the ISA bus.
There are also models that use a mix between EBus and ISA devices with
things like an AT keyboard controller and other rather interesting
devices that we might want to support in the futute hook up to the ISA
bus.
In order to not need to add sparc64 specific device_identify methods to
all of the respective ISA drivers and also not add OFW specific code to
the common ISA code make the sparc64 ISA bus code fake up PnP devices so
most ISA drivers probe their devices without further changes.
Unfortunately Sun doesn't adhere to the ISA bindings defined in IEEE
1275-1994 for the properties of most of the ISA devices which would
allow to obtain the vendor and logical IDs from their properties. So we
we just use a simple table which maps the name properties to PnP IDs.
This could be done in a more sophisticated way but I courrently don't
see the need for this. [1]
- Add the children with fully mapped and specified resources (in the OFW
sense) similar to what is done in the EBus code for the IRQ resources
of the children as adjusting the resources and the resource list entries
respectively in isa_alloc_resource() as done perviously causes trouble
with drivers which use rman_get_start(), pass-through or allocate and
release resources multiple times, etc.
Adjusting the resources might be better off in a bus_activate_resource
method but the common ISA code currently doesn't allow for an
isa_activate_resource(). [2]
With this change:
- ppbus(4) and lpt(4) attach and work (modulo ECP mode, which requires
real ISADMA code but it currently only consists of stubs on sparc64).
- atkbdc(4) and atkbdc(4) attach, no further testing done.
- fdc(4) itself attaches but causes a hang while attaching fd0 also
when is DMA disabled, further work in fdc(4) is required here as e.g.
fd0 uses the address of fd1 on sparc64 (not sure if sparc64 supports
more than one floppy drive at all).
All of these drivers previously caused panics in the sparc64 ISA code.
- Minor changes, e.g. use __FBSDID, remove a dupe word in a comment and
declare one global variable which isn't used outside of isa.c static.
o dev/uart/uart_cpu_sparc64.c and modules/uart/Makefile:
- Remove the code for registering the UARTs on the ISA bus from the
sparc64 uart_cpu_identify() again and rely on probing them via PnP.

Original idea by: tmm [1]
No objections by: tmm [1], [2]

Be slightly more paranoid about using the divisor in a division and
the calculated baudrate. Neither should be 0.

Implement UART_IOCTL_BAUD. Consequently, when the baudrate was unset
for the console, we emit the actual baudrate during bus enumeration.

Add UART_IOCTL_BAUD to allow us to query the hardware about the
current baudrate setting. Use this ioctl() when we don't know the
baudrate of the sysdev (as represented by a 0 value). When the
ioctl() fails, e.g. when the backend hasn't implemented it or the
hardware doesn't provide the means to determine its current baudrate
setting, we invalidate the baudrate setting by setting it to -1.
None of the backends currently implement the new ioctl().

Make sure the baudrate specified with the BR tag is somewhat sane.
A baudrate we consider insane is silently replaced with 0. When the
baudrate is 0, we will not try to program the hardware. Instead we
leave the communication speed unaltered, maximizing the chance to
have a working console. Obviously this means we allow specifying a
0 baudrate for exactly that purpose.

Remove asserts which are not correct if the port is a tty.

Use generic tty code instead of (comparatively little) local copies.

Use tty->t_sc to find out softc.

Use ttyalloc() instead of ttymalloc(NULL)

Don't call uart_bus_probe() for non-matching PnP-devices. Trying to probe
the keyboard controller with uart_bus_probe() caused a hang here on an i386
machine.

Approved by: marcel

Fix a style(9) bug (variable definitions inside a nested scope) a patch
of mine introduced in revision 1.10.

Approved by: marcel
Prodded by: marcel

- Introduce an uart_cpu_identify() which is implemented in uart_cpu_<arch>.c
and that can be used as an identify function for all kinds of busses on a
certain platform. Expect for sparc64 these are only stubs right now. [1]
- For sparc64, add code to its uart_cpu_identify() for registering the on-
board ISA UARTs and their resources based on information obtained from
Open Firmware.
It would be better if this would be done in the OFW ISA code. However, due
to the common FreeBSD ISA code and PNP-IDs not always being present in the
properties of the ISA nodes there seems to be no good way to implement that.
Therefore special casing UARTs as the sole really relevant ISA devices on
sparc64 seemed reasonable. [2]

Approved by: marcel
Discussed with: marcel [1], tmm [2]
Tested by: make universe

- Introduce an ofw_bus kobj-interface for retrieving the OFW node and a
subset ("compatible", "device_type", "model" and "name") of the standard
properties in drivers for devices on Open Firmware supported busses. The
standard properties "reg", "interrupts" und "address" are not covered by
this interface because they are only of interest in the respective bridge
code. There's a remaining standard property "status" which is unclear how
to support properly but which also isn't used in FreeBSD at present.
This ofw_bus kobj-interface allows to replace the various (ebus_get_node(),
ofw_pci_get_node(), etc.) and partially inconsistent (central_get_type()
vs. sbus_get_device_type(), etc.) existing IVAR ones with a common one.
This in turn allows to simplify and remove code-duplication in drivers for
devices that can hang off of more than one OFW supported bus.
- Convert the sparc64 Central, EBus, FHC, PCI and SBus bus drivers and the
drivers for their children to use the ofw_bus kobj-interface. The IVAR-
interfaces of the Central, EBus and FHC are entirely replaced by this. The
PCI bus driver used its own kobj-interface and now also uses the ofw_bus
one. The IVARs special to the SBus, e.g. for retrieving the burst size,
remain.
Beware: this causes an ABI-breakage for modules of drivers which used the
IVAR-interfaces, i.e. esp(4), hme(4), isp(4) and uart(4), which need to be
recompiled.
The style-inconsistencies introduced in some of the bus drivers will be
fixed by tmm@ in a generic clean-up of the respective drivers later (he
requested to add the changes in the "new" style).
- Convert the powerpc MacIO bus driver and the drivers for its children to
use the ofw_bus kobj-interface. This invloves removing the IVARs related
to the "reg" property which were unused and a leftover from the NetBSD
origini of the code. There's no ABI-breakage caused by this because none
of these driver are currently built as modules.
There are other powerpc bus drivers which can be converted to the ofw_bus
kobj-interface, e.g. the PCI bus driver, which should be done together
with converting powerpc to use the OFW PCI code from sparc64.
- Make the SBus and FHC front-end of zs(4) and the sparc64 eeprom(4) take
advantage of the ofw_bus kobj-interface and simplify them a bit.

Reviewed by: grehan, tmm
Approved by: re (scottl)
Discussed with: tmm
Tested with: Sun AX1105, AXe, Ultra 2, Ultra 60; PPC cross-build on i386

Do not use hardware flow control for the moment. There are some issues
with it that need to be understood better before they can be resolved.
This takes time and time is already in short supply.

Reported & tested by: glebius@

When sizing the FIFO, don't count all the way up to 1030 if any FIFO
size larger than 128 is considered an incompatible size. Stop counting
when we reach 130 in the loop.

Preparation commit for the tty cleanups that will follow in the near
future:

rename ttyopen() -> tty_open() and ttyclose() -> tty_close().

We need the ttyopen() and ttyclose() for the new generic cdevsw
functions for tty devices in order to have consistent naming.

Update for the KDB framework:
o Call kdb_enter() instead of breakpoint().
o Call kdb_alt_break() instead of db_alt_break().
o Make debugging code conditional upon KDB instead of DDB.

Add support for uart(4) being a debug port for the GDB backend.

Define the tty methods as typedefs.

Change the return type for t_break to void.

Add t_ioctl (more about this later).

Use generic support for BREAK and modem control ioctls.

Use the new serial port definitions for modemsignals.

save a few redundant lines by moving the retry loop further backwards.

Do the dreaded s/dev_t/struct cdev */
Bump __FreeBSD_version accordingly.

Machine generated patch which changes linedisc calls from accessing
linesw[] directly to using the ttyld...() functions

The ttyld...() functions ar inline so there is no performance hit.

Make the remaining serial drivers call ttyioctl() rather than calling
the linedisc directly.

Add missing <sys/module.h> includes currently relying on nested include
in <sys/kernel.h>

Fix disordering of pccarddevs.h noticed by bde. Also remove a few
redundant includes and fix some of the include disordering.

Submitted by: bde

It seems that clearing the MCR_IE bit in the modem control register
does not reliably prevent the triggering of interrupts for all supported
configurations. Thus, the FIFO size probe could cause an interrupt,
which could lead to an interrupt storm in the shared interrupt case.

To prevent this, change ns8250_bus_probe() to use the overflow bit in
the line status register instead of the RX ready bit in the interrupt
identification register to detect whether the FIFO has filled up.
This allows us to clear all bits in the interrupt enable register during
the probe, which should prevent interrupts reliably.
Additionally, the detected FIFO size may be a bit more accurate, because
the overflow bit is only set when the FIFO did actually fill up, while
interrupts would trigger a bit early.

Reviewed and tested on a lot of hardware by: marcel

Move to generating pccarddevs.h on the fly, both for the kernel and
the modules.

Also generate usbdevs.h automatically now, but a non-kernel file is
stopping that at the moment.

- Initialize uart_bus_space_io and uart_bus_space_mem.
- Fix wrong comment.

Fix hangs caused by z8530_bus_ipend() returning UART_IPEND_TXIDLE
not as a pending interrupt status, but as a matter of status quo.
Consequently, when there's no data to be transmitted the condition
is not cleared and uart_intr() is stuck in an infinite loop trying
to clear the UART_IPEND_TXIDLE status.
The z8530_bus_ipend() function is changed to return idle only once
after having sent any data.

The root cause for this problem is that we cannot use the interrupt
status bits of the SCC itself. The register that holds the interrupt
status can only be accessed by channel A and holds the status for
both channels. Using the interrupt status register would complicate
the driver because we need to synchronize access to the SCC between
the channels.

Elementary testing: marius

When the interrupt cannot be INTR_FAST, it still is INTR_MPSAFE.
Mark it as such.

Don't mask TCD in IMR0 when we initialize the channel. Doing so makes
it impossible to check the interrupt status bit when we try to get a
character in the low level console code.

To quote submitter:
"... uart_cpu_sparc64.c currently only looks at /options if ttyX is
the selected console. However, there's one case where it should
additionally look at /chosen. If "keyboard" is the selected input-
device and "screen" the output-device (both via /options) but the
keyboard is unplugged, OF automatically switches to ttya for the
console. It even prints a line telling so on "screen". Solaris
respects this behaviour and uses ttya as the console in this case
and people probably expect FreeBSD to do the same (it's also very
handy to temporarily switch consoles)..."

Submitted by: Marius Strobl <marius@alchemy.franken.de>
Has no doubt the change is correct: marcel

In uart_ebus_probe(), match "su_pnp" besides "su" for ns8250 family
of UARTs. We already did this in uart_cpu_getdev().
While here, also check the compat name for "su" or "su16550".

Both changes submitted by: Marius Strobl <marius@alchemy.franken.de>
Does not doubt the correctness of the second change: marcel

In ns8250_putc() insert a barrier between writing the character and
checking for transmitter empty.

Allow the selection of a debug port with hw.uart.dbgport. Unlike
other architectures (like ia64), the variable has to be set to
an OpenFirmware device name.

Call kbd_attach() only when KBD_INSTALL_CDEV is enabled as the function
is only defined in that case.

Fix braino in previous commit: getenv() can return NULL.

Introduce the hw.uart.console and hw.uart.dbgport environment variables
to select a serial console and debug port (resp). On ia64 these replace
the use of hints completely and take precedence over hints on alpha,
amd64 and i386. On sparc64 these variables are not yet recognised.

The reasons for introducing these variables are:
1. Hints have side-effects. They reserve the unit number for use by
isa or acpi devices and therefore cannot be used to select a pci
device. Also, the use of a unit number to select a device prior
to bus enumeration is nonsense. The new variables have no side-
effects and are not based on unit numbers.
2. Hints don't have the expression power to allow the sysadmin to
select UARTs that are not legacy PC devices and need the support
of compile-time constants to give the sysadmin some level of
flexibility.

The hw.uart.console and hw.uart.dbgport variables specify a list of
attributes. An attribute is a tag-value pair, seperated by a colon.
Attributes are seperated by a comma. Where possible, tags are the
same as those in /etc/remote (only br and pa in practice). Details
can be found in the manpage (not part of this commit).

Not tested on: amd64, pc98

Convert callers to the new bus_alloc_resource_any(9) API.

Submitted by: Mark Santcroos <marks@ripe.net>
Reviewed by: imp, dfr, bde

Device megapatch 4/6:

Introduce d_version field in struct cdevsw, this must always be
initialized to D_VERSION.

Flip sense of D_NOGIANT flag to D_NEEDGIANT, this involves removing
four D_NOGIANT flags and adding 145 D_NEEDGIANT flags.

Device megapatch 3/6:

Add missing D_TTY flags to various drivers.

Complete asserts that dev_t's passed to ttyread(), ttywrite(),
ttypoll() and ttykqwrite() have (d_flags & D_TTY) and a struct tty
pointer.

Make ttyread(), ttywrite(), ttypoll() and ttykqwrite() the default
cdevsw methods for D_TTY drivers and remove the explicit initializations
in various drivers cdevsw structures.

Use standard style for cdevsw initializtion

Test the return value of UART_PARAM(). Invalid line parameters did not
result in an error before.

PR: kern/60284
Submitted by: Thomas Sandford <freebsduser@paradisegreen.co.uk>

Sometimes cardbus attachments don't attach, so while we track down
this problem put these lines back in. While they should be
unnecessary, they appear to be sometimes necessary.

Reviewed in concept: dfr
Approved by: re (scottl@)

Add a uart attachment/syscons keyboard driver for sun keyboards. In theory
this will work with any uart backend, currently supported hardware uses
either ns8250 or z8530.

Allow uart to attach to keyboards that are not the firmware's notion of
stdin, such as when using a serial console. We must recognize these
devices here so that we can override the tty attach routine.

Remove explicit cardbus attachments from drivers where this is identical
to the pci attachment. Cardbus is a derived class of pci so all pci
drivers are automatically available for matching against cardbus devices.

Reviewed by: imp

Include pccard/pccard_cis.h here too

Don't explicitly initialize d_maj in the cdevsw with MAJOR_AUTO, as
per the intentions of conf.h, rev 1.176. This change is a no-op as
MAJOR_AUTO equals to 0.

Set the baud rate to 1200 if the device is a keyboard.

Catch up with the console interface change: the use of makedev() has
been abandoned in favor of a (device) name-based approach.

Submitted by: phk
Tested on: alpha

Revert the introduction of iobase in struct uart_bas. Both the SAB82532
and the Z8530 drivers used the I/O address as a quick and dirty way to
determine which channel they operated on, but formalizing this by
introducing iobase is not a solution. How for example would a driver
know which channel it controls for a multi-channel UART that only has a
single I/O range?

Instead, add an explicit field, called chan, to struct uart_bas that
holds the channel within a device, or 0 otherwise. The chan field is
initialized both by the system device probing (i.e. a system console)
or it is passed down to uart_bus_probe() by any of the bus front-ends.
As such, it impacts all platforms and bus drivers and makes it a rather
large commit.

Remove the use of iobase in uart_cpu_eqres() for pc98. It is expected
that platforms have the capability to compare tag and handle pairs for
equality; as to determine whether two pairs access the same device or
not. The use of iobase for pc98 makes it impossible to formalize this
and turn it into a real newbus function later. This commit reverts
uart_cpu_eqres() for pc98 to an unimplemented function. It has to be
reimplemented using only the tag and handle fields in struct uart_bas.

Rewrite the SAB82532 and Z8530 drivers to use the chan field in struct
uart_bas. Remove the IS_CHANNEL_A and IS_CHANNEL_B macros. We don't
need to abstract anything anymore.

Discussed with: nyan
Tested on: i386, ia64, sparc64

Don't return to search another ports even if bus_space_map() fails.

Initialize iobase, bsh and bst.

Compare base address instead of bus_handle.

- Keep the base address in struct uart_bas for sab82532 and z8530 modules.
- Remove buggy uart_cpu_busaddr() function.

Remove unneeded includes.

Use bus_space_map() to initialize a bus_handle.

In uart_intr() loop until all interrupts have been handled. Previously
an UART interface could get stuck when a new interrupt condition
arose while servicing a previous interrupt. Since an interrupt was
already pending, no new interrupt would be triggered.

Avoid infinite recursion by flushing the Rx FIFO and marking an
overrun condition when we could not move the data from the Rx
FIFO to the receive buffer in toto. Failure to flush the Rx FIFO
would leave the Rx ready condition pending.

Note that the SAB 82532 already did this due to the nature of the
chip.

Add locking to the hardware drivers. I intended to figure out more
precisely where locking would be needed before adding it, but it
seems uart(4) draws slightly too much attention to have it without
locking for too long.
The lock added is a spinlock that protects access to the underlying
hardware. As a first and obvious stab at this, each method of the
hardware interface grabs the lock. Roughly speaking this serializes
the methods. Exceptions are the probe, attach and detach methods.

Remove inclusion of <sys/timepps.h>. It's included in "uart_bus.h"
to avoid having to include it in almost all other source files.

Remove useless #ifdef PC98.

Submitted by: nyan

Add uart pccard bus attachment,based on sio_pccard.c .

Wrote at: Hakone.
Powered by: Warner Losh's scotch whisky.
Tested by: nork

Add support for automatic hardware flow control for 16[679]50 UARTs.
We simply use the detected FIFO size to determine whether we have
a post 16550 UART or not. The support lacks proper serialization of
hardware access for now.

When determining the device class to use for the serial console, check
the "compatible" property too in the ns8250 case. This gets the serial
console to work on Blade 100s, where the device name is just "serial".

Reviewed by: marcel

Add support for using uart(4) for pulse capturing for the Pulse Per
Second (PPS) timing interface. The support is non-optional and by
default uses the DCD line signal as the pulse input. A compile-time
option (UART_PPS_ON_CTS) can be used to have uart(4) use the CTS line
signal.

Include <sys/timepps.h> in uart_bus.h to avoid having to add the
inclusion of that header in all source files.

Reviewed by: phk

Minor commentary cleanup, since I didn't understand the comments that
I wrote.

Fix compile on pc98. Maybe this is correct.

If we failed to size the Rx FIFO, assume the worst. This however
is not a size of 1. Since we already know there is a FIFO, we can
safely assume that it is at least 16 bytes. Note that all this is
mostly academic anyway. We don't use the size of the Rx FIFO
currently. If we add support for hardware flow control, we only
care about Rx FIFO sizes larger than 16.

Remove the assumption that a bus_space_handle_t is an I/O address
from the SAB82532 and the Z8530 hardware drivers by introducing
uart_cpu_busaddr(). The assumption is not true on pc98 where
bus_space_handle_t is a pointer to a structure.
The uart_cpu_busaddr() function will return the bus address
corresponding the tag and handle given to it by the BAS.

WARNING: the intend of the function is STRICTLY to allow hardware
drivers to determine which logical channel they control and is NOT
to be used for actual I/O. It is therefore EXPLICITLY allowed that
uart_cpu_busaddr() returns only the lower 8 bits of the address
and garbage in all other bits. No mistakes...

Better stab at MD code for pc98. The 8251 stuff is a total lie
(ns8250 copied and s/ns8250/i8251/g), but there for linkage purposes.
Real code to follow, once I get past some boot issues on my pc98 boxes
with recent current.

The uart(4) driver is an universal driver for various UART hardware.
It improves on sio(4) in the following areas:
o Fully newbusified to allow for memory mapped I/O. This is a must
for ia64 and sparc64,
o Machine dependent code to take full advantage of machine and firm-
ware specific ways to define serial consoles and/or debug ports.
o Hardware abstraction layer to allow the driver to be used with
various UARTs, such as the well-known ns8250 family of UARTs, the
Siemens sab82532 or the Zilog Z8530. This is especially important
for pc98 and sparc64 where it's common to have different UARTs,
o The notion of system devices to unkludge low-level consoles and
remote gdb ports and provides the mechanics necessary to support
the keyboard on sparc64 (which is UART based).
o The notion of a kernel interface so that a UART can be tied to
something other than the well-known TTY interface. This is needed
on sparc64 to present the user with a device and ioctl handling
suitable for a keyboard, but also allows us to cleanly hide an
UART when used as a debug port.

Following is a list of features and bugs/flaws specific to the ns8250
family of UARTs as compared to their support in sio(4):
o The uart(4) driver determines the FIFO size and automaticly takes
advantages of larger FIFOs and/or additional features. Note that
since I don't have sufficient access to 16[679]5x UARTs, hardware
flow control has not been enabled. This is almost trivial to do,
provided one can test. The downside of this is that broken UARTs
are more likely to not work correctly with uart(4). The need for
tunables or knobs may be large enough to warrant their creation.
o The uart(4) driver does not share the same bumpy history as sio(4)
and will therefore not provide the necessary hooks, tweaks, quirks
or work-arounds to deal with once common hardware. To that extend,
uart(4) supports a subset of the UARTs that sio(4) supports. The
question before us is whether the subset is sufficient for current
hardware.
o There is no support for multiport UARTs in uart(4). The decision
behind this is that uart(4) deals with one EIA RS232-C interface.
Packaging of multiple interfaces in a single chip or on a single
expansion board is beyond the scope of uart(4) and is now mostly
left for puc(4) to deal with. Lack of hardware made it impossible
to actually implement such a dependency other than is present for
the dual channel SAB82532 and Z8350 SCCs.

The current list of missing features is:
o No configuration capabilities. A set of tunables and sysctls is
being worked out. There are likely not going to be any or much
compile-time knobs. Such configuration does not fit well with
current hardware.
o No support for the PPS API. This is partly dependent on the
ability to configure uart(4) and partly dependent on having
sufficient information to implement it properly.

As usual, the manpage is present but lacks the attention the
software has gotten.