xref: /f-stack/freebsd/x86/xen/pvcpu_enum.c (revision 22ce4aff)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2013 Roger Pau Monné <[email protected]>
5  * All rights reserved.
6  * Copyright (c) 2003 John Baldwin <[email protected]>
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 
61 static int xenpv_probe(void);
62 static int xenpv_probe_cpus(void);
63 static int xenpv_setup_local(void);
64 static int xenpv_setup_io(void);
65 
66 static ACPI_TABLE_MADT *madt;
67 static vm_paddr_t madt_physaddr;
68 static vm_offset_t madt_length;
69 
70 static 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  */
83 static void
madt_parse_interrupt_override(ACPI_MADT_INTERRUPT_OVERRIDE * intr)84 madt_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  */
117 static void
madt_walk_table(acpi_subtable_handler * handler,void * arg)118 madt_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  */
128 static void
madt_parse_ints(ACPI_SUBTABLE_HEADER * entry,void * arg __unused)129 madt_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  */
142 static int
xenpv_probe(void)143 xenpv_probe(void)
144 {
145 	return (0);
146 }
147 
148 /*
149  * Test each possible vCPU in order to find the number of vCPUs
150  */
151 static int
xenpv_probe_cpus(void)152 xenpv_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  */
170 static int
xenpv_setup_local(void)171 xenpv_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  */
191 static int
xenpv_setup_io(void)192 xenpv_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(255, num_io_irqs);
203 
204 		acpi_SetDefaultIntrModel(ACPI_INTR_APIC);
205 	}
206 	return (0);
207 }
208 
209 void
xenpv_register_pirqs(struct pic * pic __unused)210 xenpv_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 
257 static void
xenpv_register(void * dummy __unused)258 xenpv_register(void *dummy __unused)
259 {
260 	if (xen_pv_domain()) {
261 		apic_register_enumerator(&xenpv_enumerator);
262 	}
263 }
264 SYSINIT(xenpv_register, SI_SUB_TUNABLES - 1, SI_ORDER_FIRST, xenpv_register, NULL);
265