History log of /freebsd-10-stable/sys/dev/mmc/mmcvar.h
Revision Date Author Comments
# 322389 11-Aug-2017 marius

MFC: r322209

- If available, use TRIM instead of ERASE for implementing BIO_DELETE.
This also involves adding a quirk table as TRIM is broken for some
Kingston eMMC devices, though. Compared to ERASE (declared "legacy"
in the eMMC specification v5.1), TRIM has the advantage of operating
on write sectors rather than on erase sectors, which typically are
of a much larger size. Thus, employing TRIM, we don't need to fiddle
with coalescing BIO_DELETE requests that are also of (write) sector
units into erase sectors, which might not even add up in all cases.
- For some SanDisk iNAND devices, the CMD38 argument, e. g. ERASE,
TRIM etc., has to be specified via EXT_CSD[113], which now is also
handled via a quirk.
- My initial understanding was that for eMMC partitions, the granularity
should be used as erase sector size, e. g. 128 KB for boot partitions.
However, rereading the relevant parts of the eMMC specification v5.1,
this isn't actually correct. So drop the code which used partition
granularities for delmaxsize and stripesize. For the most part, this
change is a NOP, though, because a) for ERASE, mmcsd_delete() used
the erase sector size unconditionally for all partitions anyway and
b) g_disk_limit() doesn't actually take the stripesize into account.
- Take some more advantage of mmcsd_errmsg() in mmcsd(4) for making
error codes human readable.


# 318198 11-May-2017 marius

MFC: r292180 (partial), r297127 (partial), r311911, r311923, r312939,
r313250, r313712, r314811 (partial), r314887 (partial), r315430,
r317981, r315466

o Move the DRIVER_MODULE() statements that declare mmc(4) to be a child
of the various bridge drivers out of dev/mmc.c and into the bridge
drivers.

o Add ACPI platform support for SDHCI driver.

o Fix some overly long lines, whitespace and other bugs according to
style(9) as well as spelling etc. in mmc(4), mmcsd(4) and sdhci(4).

o In the mmc(4) bridges and sdhci(4) (bus) front-ends:
- Remove redundant assignments of the default bus_generic_print_child
device method,
- use DEVMETHOD_END,
- use NULL instead of 0 for pointers.

o Trim/adjust includes.

o Add and use a MMC_DECLARE_BRIDGE macro for declaring mmc(4) bridges
as kernel drivers and their dependency onto mmc(4).

o Add support for eMMC "partitions". Besides the user data area, i. e.
the default partition, eMMC v4.41 and later devices can additionally
provide up to:
1 enhanced user data area partition
2 boot partitions
1 RPMB (Replay Protected Memory Block) partition
4 general purpose partitions (optionally with a enhanced or extended
attribute)

Besides simply subdividing eMMC devices, some Intel NUCs having UEFI
code in the boot partitions etc., another use case for the partition
support is the activation of pseudo-SLC mode, which manufacturers of
eMMC chips typically associate with the enhanced user data area and/
or the enhanced attribute of general purpose partitions.

CAVEAT EMPTOR: Partitioning eMMC devices is a one-time operation.

o Now that properly issuing CMD6 is crucial (so data isn't written to
the wrong partition for example), make a step into the direction of
correctly handling the timeout for these commands in the MMC layer.
Also, do a SEND_STATUS when CMD6 is invoked with an R1B response as
recommended by relevant specifications.

o Add an IOCTL interface to mmcsd(4); this is sufficiently compatible
with Linux so that the GNU mmc-utils can be ported to and used with
FreeBSD (note that due to the remaining deficiencies outlined above
SANITIZE operations issued by/with `mmc` currently most likely will
fail). These latter have been added to ports as sysutils/mmc-utils.
Among others, the `mmc` tool of mmc-utils allows for partitioning
eMMC devices (tested working).

o For devices following the eMMC specification v4.41 or later, year 0
is 2013 rather than 1997; so correct this for assembling the device
ID string properly.

o Let mmcsd.ko depend on mmc.ko. Additionally, bump MMC_VERSION as at
least for some of the above a matching pair is required.


# 269795 10-Aug-2014 ian

MFC r269341: Populate disk->d_ident with the sd or mmc card's serial number.


# 269795 10-Aug-2014 ian

MFC r269341: Populate disk->d_ident with the sd or mmc card's serial number.