1/*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2013 Roger Pau Monn�� <roger.pau@citrix.com>
5 * All rights reserved.
6 * Copyright (c) 2003 John Baldwin <jhb@FreeBSD.org>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/bus.h>
36#include <sys/kernel.h>
37#include <sys/smp.h>
38#include <sys/pcpu.h>
39#include <vm/vm.h>
40#include <vm/pmap.h>
41
42#include <machine/intr_machdep.h>
43#include <x86/apicvar.h>
44
45#include <machine/cpu.h>
46#include <machine/smp.h>
47#include <machine/md_var.h>
48
49#include <xen/xen-os.h>
50#include <xen/xen_intr.h>
51#include <xen/hypervisor.h>
52
53#include <xen/interface/vcpu.h>
54
55#include <contrib/dev/acpica/include/acpi.h>
56#include <contrib/dev/acpica/include/aclocal.h>
57#include <contrib/dev/acpica/include/actables.h>
58
59#include <dev/acpica/acpivar.h>
60
61static int xenpv_probe(void);
62static int xenpv_probe_cpus(void);
63static int xenpv_setup_local(void);
64static int xenpv_setup_io(void);
65
66static ACPI_TABLE_MADT *madt;
67static vm_paddr_t madt_physaddr;
68static vm_offset_t madt_length;
69
70static struct apic_enumerator xenpv_enumerator = {
71	.apic_name = "Xen PV",
72	.apic_probe = xenpv_probe,
73	.apic_probe_cpus = xenpv_probe_cpus,
74	.apic_setup_local = xenpv_setup_local,
75	.apic_setup_io = xenpv_setup_io
76};
77
78/*--------------------- Helper functions to parse MADT -----------------------*/
79
80/*
81 * Parse an interrupt source override for an ISA interrupt.
82 */
83static void
84madt_parse_interrupt_override(ACPI_MADT_INTERRUPT_OVERRIDE *intr)
85{
86	enum intr_trigger trig;
87	enum intr_polarity pol;
88	int ret;
89
90	if (acpi_quirks & ACPI_Q_MADT_IRQ0 && intr->SourceIrq == 0 &&
91	    intr->GlobalIrq == 2) {
92		if (bootverbose)
93			printf("MADT: Skipping timer override\n");
94		return;
95	}
96
97	madt_parse_interrupt_values(intr, &trig, &pol);
98
99	/* Remap the IRQ if it is mapped to a different interrupt vector. */
100	if (intr->SourceIrq != intr->GlobalIrq && intr->GlobalIrq > 15 &&
101	    intr->SourceIrq == AcpiGbl_FADT.SciInterrupt)
102		/*
103		 * If the SCI is remapped to a non-ISA global interrupt,
104		 * then override the vector we use to setup.
105		 */
106		acpi_OverrideInterruptLevel(intr->GlobalIrq);
107
108	/* Register the IRQ with the polarity and trigger mode found. */
109	ret = xen_register_pirq(intr->GlobalIrq, trig, pol);
110	if (ret != 0)
111		panic("Unable to register interrupt override");
112}
113
114/*
115 * Call the handler routine for each entry in the MADT table.
116 */
117static void
118madt_walk_table(acpi_subtable_handler *handler, void *arg)
119{
120
121	acpi_walk_subtables(madt + 1, (char *)madt + madt->Header.Length,
122	    handler, arg);
123}
124
125/*
126 * Parse interrupt entries.
127 */
128static void
129madt_parse_ints(ACPI_SUBTABLE_HEADER *entry, void *arg __unused)
130{
131
132	if (entry->Type == ACPI_MADT_TYPE_INTERRUPT_OVERRIDE)
133		madt_parse_interrupt_override(
134		    (ACPI_MADT_INTERRUPT_OVERRIDE *)entry);
135}
136
137/*---------------------------- Xen PV enumerator -----------------------------*/
138
139/*
140 * This enumerator will only be registered on PVH
141 */
142static int
143xenpv_probe(void)
144{
145	return (0);
146}
147
148/*
149 * Test each possible vCPU in order to find the number of vCPUs
150 */
151static int
152xenpv_probe_cpus(void)
153{
154#ifdef SMP
155	int i, ret;
156
157	for (i = 0; i < MAXCPU && (i * 2) < MAX_APIC_ID; i++) {
158		ret = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
159		mp_ncpus = min(mp_ncpus + 1, MAXCPU);
160	}
161	mp_maxid = mp_ncpus - 1;
162	max_apic_id = mp_ncpus * 2;
163#endif
164	return (0);
165}
166
167/*
168 * Initialize the vCPU id of the BSP
169 */
170static int
171xenpv_setup_local(void)
172{
173#ifdef SMP
174	int i, ret;
175
176	for (i = 0; i < MAXCPU && (i * 2) < MAX_APIC_ID; i++) {
177		ret = HYPERVISOR_vcpu_op(VCPUOP_is_up, i, NULL);
178		if (ret >= 0)
179			lapic_create((i * 2), (i == 0));
180	}
181#endif
182
183	PCPU_SET(vcpu_id, 0);
184	lapic_init(0);
185	return (0);
186}
187
188/*
189 * On PVH guests there's no IO APIC
190 */
191static int
192xenpv_setup_io(void)
193{
194
195	if (xen_initial_domain()) {
196		/*
197		 * NB: we could iterate over the MADT IOAPIC entries in order
198		 * to figure out the exact number of IOAPIC interrupts, but
199		 * this is legacy code so just keep using the previous
200		 * behaviour and assume a maximum of 256 interrupts.
201		 */
202		num_io_irqs = max(MINIMUM_MSI_INT - 1, num_io_irqs);
203
204		acpi_SetDefaultIntrModel(ACPI_INTR_APIC);
205	}
206	return (0);
207}
208
209void
210xenpv_register_pirqs(struct pic *pic __unused)
211{
212	unsigned int i;
213	int ret;
214
215	/* Map MADT */
216	madt_physaddr = acpi_find_table(ACPI_SIG_MADT);
217	madt = acpi_map_table(madt_physaddr, ACPI_SIG_MADT);
218	madt_length = madt->Header.Length;
219
220	/* Try to initialize ACPI so that we can access the FADT. */
221	ret = acpi_Startup();
222	if (ACPI_FAILURE(ret)) {
223		printf("MADT: ACPI Startup failed with %s\n",
224		    AcpiFormatException(ret));
225		printf("Try disabling either ACPI or apic support.\n");
226		panic("Using MADT but ACPI doesn't work");
227	}
228
229	/* Run through the table to see if there are any overrides. */
230	madt_walk_table(madt_parse_ints, NULL);
231
232	/*
233	 * If there was not an explicit override entry for the SCI,
234	 * force it to use level trigger and active-low polarity.
235	 */
236	if (!madt_found_sci_override) {
237		printf(
238"MADT: Forcing active-low polarity and level trigger for SCI\n");
239		ret = xen_register_pirq(AcpiGbl_FADT.SciInterrupt,
240		    INTR_TRIGGER_LEVEL, INTR_POLARITY_LOW);
241		if (ret != 0)
242			panic("Unable to register SCI IRQ");
243	}
244
245	/* Register legacy ISA IRQs */
246	for (i = 1; i < 16; i++) {
247		if (intr_lookup_source(i) != NULL)
248			continue;
249		ret = xen_register_pirq(i, INTR_TRIGGER_EDGE,
250		    INTR_POLARITY_LOW);
251		if (ret != 0 && bootverbose)
252			printf("Unable to register legacy IRQ#%u: %d\n", i,
253			    ret);
254	}
255}
256
257static void
258xenpv_register(void *dummy __unused)
259{
260	if (xen_pv_domain()) {
261		apic_register_enumerator(&xenpv_enumerator);
262	}
263}
264SYSINIT(xenpv_register, SI_SUB_TUNABLES - 1, SI_ORDER_FIRST, xenpv_register, NULL);
265