xref: /openbmc/qemu/hw/intc/arm_gic_common.c (revision 979a8902)
1 /*
2  * ARM GIC support - common bits of emulated and KVM kernel model
3  *
4  * Copyright (c) 2012 Linaro Limited
5  * Written by Peter Maydell
6  *
7  * This program is free software; you can redistribute it and/or modify
8  * it under the terms of the GNU General Public License as published by
9  * the Free Software Foundation, either version 2 of the License, or
10  * (at your option) any later version.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  * GNU General Public License for more details.
16  *
17  * You should have received a copy of the GNU General Public License along
18  * with this program; if not, see <http://www.gnu.org/licenses/>.
19  */
20 
21 #include "qemu/osdep.h"
22 #include "qapi/error.h"
23 #include "qemu/module.h"
24 #include "gic_internal.h"
25 #include "hw/arm/linux-boot-if.h"
26 #include "hw/qdev-properties.h"
27 #include "migration/vmstate.h"
28 
29 static int gic_pre_save(void *opaque)
30 {
31     GICState *s = (GICState *)opaque;
32     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
33 
34     if (c->pre_save) {
35         c->pre_save(s);
36     }
37 
38     return 0;
39 }
40 
41 static int gic_post_load(void *opaque, int version_id)
42 {
43     GICState *s = (GICState *)opaque;
44     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
45 
46     if (c->post_load) {
47         c->post_load(s);
48     }
49     return 0;
50 }
51 
52 static bool gic_virt_state_needed(void *opaque)
53 {
54     GICState *s = (GICState *)opaque;
55 
56     return s->virt_extn;
57 }
58 
59 static const VMStateDescription vmstate_gic_irq_state = {
60     .name = "arm_gic_irq_state",
61     .version_id = 1,
62     .minimum_version_id = 1,
63     .fields = (VMStateField[]) {
64         VMSTATE_UINT8(enabled, gic_irq_state),
65         VMSTATE_UINT8(pending, gic_irq_state),
66         VMSTATE_UINT8(active, gic_irq_state),
67         VMSTATE_UINT8(level, gic_irq_state),
68         VMSTATE_BOOL(model, gic_irq_state),
69         VMSTATE_BOOL(edge_trigger, gic_irq_state),
70         VMSTATE_UINT8(group, gic_irq_state),
71         VMSTATE_END_OF_LIST()
72     }
73 };
74 
75 static const VMStateDescription vmstate_gic_virt_state = {
76     .name = "arm_gic_virt_state",
77     .version_id = 1,
78     .minimum_version_id = 1,
79     .needed = gic_virt_state_needed,
80     .fields = (VMStateField[]) {
81         /* Virtual interface */
82         VMSTATE_UINT32_ARRAY(h_hcr, GICState, GIC_NCPU),
83         VMSTATE_UINT32_ARRAY(h_misr, GICState, GIC_NCPU),
84         VMSTATE_UINT32_2DARRAY(h_lr, GICState, GIC_MAX_LR, GIC_NCPU),
85         VMSTATE_UINT32_ARRAY(h_apr, GICState, GIC_NCPU),
86 
87         /* Virtual CPU interfaces */
88         VMSTATE_UINT32_SUB_ARRAY(cpu_ctlr, GICState, GIC_NCPU, GIC_NCPU),
89         VMSTATE_UINT16_SUB_ARRAY(priority_mask, GICState, GIC_NCPU, GIC_NCPU),
90         VMSTATE_UINT16_SUB_ARRAY(running_priority, GICState, GIC_NCPU, GIC_NCPU),
91         VMSTATE_UINT16_SUB_ARRAY(current_pending, GICState, GIC_NCPU, GIC_NCPU),
92         VMSTATE_UINT8_SUB_ARRAY(bpr, GICState, GIC_NCPU, GIC_NCPU),
93         VMSTATE_UINT8_SUB_ARRAY(abpr, GICState, GIC_NCPU, GIC_NCPU),
94 
95         VMSTATE_END_OF_LIST()
96     }
97 };
98 
99 static const VMStateDescription vmstate_gic = {
100     .name = "arm_gic",
101     .version_id = 12,
102     .minimum_version_id = 12,
103     .pre_save = gic_pre_save,
104     .post_load = gic_post_load,
105     .fields = (VMStateField[]) {
106         VMSTATE_UINT32(ctlr, GICState),
107         VMSTATE_UINT32_SUB_ARRAY(cpu_ctlr, GICState, 0, GIC_NCPU),
108         VMSTATE_STRUCT_ARRAY(irq_state, GICState, GIC_MAXIRQ, 1,
109                              vmstate_gic_irq_state, gic_irq_state),
110         VMSTATE_UINT8_ARRAY(irq_target, GICState, GIC_MAXIRQ),
111         VMSTATE_UINT8_2DARRAY(priority1, GICState, GIC_INTERNAL, GIC_NCPU),
112         VMSTATE_UINT8_ARRAY(priority2, GICState, GIC_MAXIRQ - GIC_INTERNAL),
113         VMSTATE_UINT8_2DARRAY(sgi_pending, GICState, GIC_NR_SGIS, GIC_NCPU),
114         VMSTATE_UINT16_SUB_ARRAY(priority_mask, GICState, 0, GIC_NCPU),
115         VMSTATE_UINT16_SUB_ARRAY(running_priority, GICState, 0, GIC_NCPU),
116         VMSTATE_UINT16_SUB_ARRAY(current_pending, GICState, 0, GIC_NCPU),
117         VMSTATE_UINT8_SUB_ARRAY(bpr, GICState, 0, GIC_NCPU),
118         VMSTATE_UINT8_SUB_ARRAY(abpr, GICState, 0, GIC_NCPU),
119         VMSTATE_UINT32_2DARRAY(apr, GICState, GIC_NR_APRS, GIC_NCPU),
120         VMSTATE_UINT32_2DARRAY(nsapr, GICState, GIC_NR_APRS, GIC_NCPU),
121         VMSTATE_END_OF_LIST()
122     },
123     .subsections = (const VMStateDescription * []) {
124         &vmstate_gic_virt_state,
125         NULL
126     }
127 };
128 
129 void gic_init_irqs_and_mmio(GICState *s, qemu_irq_handler handler,
130                             const MemoryRegionOps *ops,
131                             const MemoryRegionOps *virt_ops)
132 {
133     SysBusDevice *sbd = SYS_BUS_DEVICE(s);
134     int i = s->num_irq - GIC_INTERNAL;
135 
136     /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
137      * GPIO array layout is thus:
138      *  [0..N-1] SPIs
139      *  [N..N+31] PPIs for CPU 0
140      *  [N+32..N+63] PPIs for CPU 1
141      *   ...
142      */
143     i += (GIC_INTERNAL * s->num_cpu);
144     qdev_init_gpio_in(DEVICE(s), handler, i);
145 
146     for (i = 0; i < s->num_cpu; i++) {
147         sysbus_init_irq(sbd, &s->parent_irq[i]);
148     }
149     for (i = 0; i < s->num_cpu; i++) {
150         sysbus_init_irq(sbd, &s->parent_fiq[i]);
151     }
152     for (i = 0; i < s->num_cpu; i++) {
153         sysbus_init_irq(sbd, &s->parent_virq[i]);
154     }
155     for (i = 0; i < s->num_cpu; i++) {
156         sysbus_init_irq(sbd, &s->parent_vfiq[i]);
157     }
158     if (s->virt_extn) {
159         for (i = 0; i < s->num_cpu; i++) {
160             sysbus_init_irq(sbd, &s->maintenance_irq[i]);
161         }
162     }
163 
164     /* Distributor */
165     memory_region_init_io(&s->iomem, OBJECT(s), ops, s, "gic_dist", 0x1000);
166     sysbus_init_mmio(sbd, &s->iomem);
167 
168     /* This is the main CPU interface "for this core". It is always
169      * present because it is required by both software emulation and KVM.
170      */
171     memory_region_init_io(&s->cpuiomem[0], OBJECT(s), ops ? &ops[1] : NULL,
172                           s, "gic_cpu", s->revision == 2 ? 0x2000 : 0x100);
173     sysbus_init_mmio(sbd, &s->cpuiomem[0]);
174 
175     if (s->virt_extn) {
176         memory_region_init_io(&s->vifaceiomem[0], OBJECT(s), virt_ops,
177                               s, "gic_viface", 0x1000);
178         sysbus_init_mmio(sbd, &s->vifaceiomem[0]);
179 
180         memory_region_init_io(&s->vcpuiomem, OBJECT(s),
181                               virt_ops ? &virt_ops[1] : NULL,
182                               s, "gic_vcpu", 0x2000);
183         sysbus_init_mmio(sbd, &s->vcpuiomem);
184     }
185 }
186 
187 static void arm_gic_common_realize(DeviceState *dev, Error **errp)
188 {
189     GICState *s = ARM_GIC_COMMON(dev);
190     int num_irq = s->num_irq;
191 
192     if (s->num_cpu > GIC_NCPU) {
193         error_setg(errp, "requested %u CPUs exceeds GIC maximum %d",
194                    s->num_cpu, GIC_NCPU);
195         return;
196     }
197     if (s->num_irq > GIC_MAXIRQ) {
198         error_setg(errp,
199                    "requested %u interrupt lines exceeds GIC maximum %d",
200                    num_irq, GIC_MAXIRQ);
201         return;
202     }
203     /* ITLinesNumber is represented as (N / 32) - 1 (see
204      * gic_dist_readb) so this is an implementation imposed
205      * restriction, not an architectural one:
206      */
207     if (s->num_irq < 32 || (s->num_irq % 32)) {
208         error_setg(errp,
209                    "%d interrupt lines unsupported: not divisible by 32",
210                    num_irq);
211         return;
212     }
213 
214     if (s->security_extn &&
215         (s->revision == REV_11MPCORE)) {
216         error_setg(errp, "this GIC revision does not implement "
217                    "the security extensions");
218         return;
219     }
220 
221     if (s->virt_extn) {
222         if (s->revision != 2) {
223             error_setg(errp, "GIC virtualization extensions are only "
224                        "supported by revision 2");
225             return;
226         }
227 
228         /* For now, set the number of implemented LRs to 4, as found in most
229          * real GICv2. This could be promoted as a QOM property if we need to
230          * emulate a variant with another num_lrs.
231          */
232         s->num_lrs = 4;
233     }
234 }
235 
236 static inline void arm_gic_common_reset_irq_state(GICState *s, int first_cpu,
237                                                   int resetprio)
238 {
239     int i, j;
240 
241     for (i = first_cpu; i < first_cpu + s->num_cpu; i++) {
242         if (s->revision == REV_11MPCORE) {
243             s->priority_mask[i] = 0xf0;
244         } else {
245             s->priority_mask[i] = resetprio;
246         }
247         s->current_pending[i] = 1023;
248         s->running_priority[i] = 0x100;
249         s->cpu_ctlr[i] = 0;
250         s->bpr[i] = gic_is_vcpu(i) ? GIC_VIRT_MIN_BPR : GIC_MIN_BPR;
251         s->abpr[i] = gic_is_vcpu(i) ? GIC_VIRT_MIN_ABPR : GIC_MIN_ABPR;
252 
253         if (!gic_is_vcpu(i)) {
254             for (j = 0; j < GIC_INTERNAL; j++) {
255                 s->priority1[j][i] = resetprio;
256             }
257             for (j = 0; j < GIC_NR_SGIS; j++) {
258                 s->sgi_pending[j][i] = 0;
259             }
260         }
261     }
262 }
263 
264 static void arm_gic_common_reset(DeviceState *dev)
265 {
266     GICState *s = ARM_GIC_COMMON(dev);
267     int i, j;
268     int resetprio;
269 
270     /* If we're resetting a TZ-aware GIC as if secure firmware
271      * had set it up ready to start a kernel in non-secure,
272      * we need to set interrupt priorities to a "zero for the
273      * NS view" value. This is particularly critical for the
274      * priority_mask[] values, because if they are zero then NS
275      * code cannot ever rewrite the priority to anything else.
276      */
277     if (s->security_extn && s->irq_reset_nonsecure) {
278         resetprio = 0x80;
279     } else {
280         resetprio = 0;
281     }
282 
283     memset(s->irq_state, 0, GIC_MAXIRQ * sizeof(gic_irq_state));
284     arm_gic_common_reset_irq_state(s, 0, resetprio);
285 
286     if (s->virt_extn) {
287         /* vCPU states are stored at indexes GIC_NCPU .. GIC_NCPU+num_cpu.
288          * The exposed vCPU interface does not have security extensions.
289          */
290         arm_gic_common_reset_irq_state(s, GIC_NCPU, 0);
291     }
292 
293     for (i = 0; i < GIC_NR_SGIS; i++) {
294         GIC_DIST_SET_ENABLED(i, ALL_CPU_MASK);
295         GIC_DIST_SET_EDGE_TRIGGER(i);
296     }
297 
298     for (i = 0; i < ARRAY_SIZE(s->priority2); i++) {
299         s->priority2[i] = resetprio;
300     }
301 
302     for (i = 0; i < GIC_MAXIRQ; i++) {
303         /* For uniprocessor GICs all interrupts always target the sole CPU */
304         if (s->num_cpu == 1) {
305             s->irq_target[i] = 1;
306         } else {
307             s->irq_target[i] = 0;
308         }
309     }
310     if (s->security_extn && s->irq_reset_nonsecure) {
311         for (i = 0; i < GIC_MAXIRQ; i++) {
312             GIC_DIST_SET_GROUP(i, ALL_CPU_MASK);
313         }
314     }
315 
316     if (s->virt_extn) {
317         for (i = 0; i < s->num_lrs; i++) {
318             for (j = 0; j < s->num_cpu; j++) {
319                 s->h_lr[i][j] = 0;
320             }
321         }
322 
323         for (i = 0; i < s->num_cpu; i++) {
324             s->h_hcr[i] = 0;
325             s->h_misr[i] = 0;
326         }
327     }
328 
329     s->ctlr = 0;
330 }
331 
332 static void arm_gic_common_linux_init(ARMLinuxBootIf *obj,
333                                       bool secure_boot)
334 {
335     GICState *s = ARM_GIC_COMMON(obj);
336 
337     if (s->security_extn && !secure_boot) {
338         /* We're directly booting a kernel into NonSecure. If this GIC
339          * implements the security extensions then we must configure it
340          * to have all the interrupts be NonSecure (this is a job that
341          * is done by the Secure boot firmware in real hardware, and in
342          * this mode QEMU is acting as a minimalist firmware-and-bootloader
343          * equivalent).
344          */
345         s->irq_reset_nonsecure = true;
346     }
347 }
348 
349 static Property arm_gic_common_properties[] = {
350     DEFINE_PROP_UINT32("num-cpu", GICState, num_cpu, 1),
351     DEFINE_PROP_UINT32("num-irq", GICState, num_irq, 32),
352     /* Revision can be 1 or 2 for GIC architecture specification
353      * versions 1 or 2, or 0 to indicate the legacy 11MPCore GIC.
354      */
355     DEFINE_PROP_UINT32("revision", GICState, revision, 1),
356     /* True if the GIC should implement the security extensions */
357     DEFINE_PROP_BOOL("has-security-extensions", GICState, security_extn, 0),
358     /* True if the GIC should implement the virtualization extensions */
359     DEFINE_PROP_BOOL("has-virtualization-extensions", GICState, virt_extn, 0),
360     DEFINE_PROP_END_OF_LIST(),
361 };
362 
363 static void arm_gic_common_class_init(ObjectClass *klass, void *data)
364 {
365     DeviceClass *dc = DEVICE_CLASS(klass);
366     ARMLinuxBootIfClass *albifc = ARM_LINUX_BOOT_IF_CLASS(klass);
367 
368     dc->reset = arm_gic_common_reset;
369     dc->realize = arm_gic_common_realize;
370     device_class_set_props(dc, arm_gic_common_properties);
371     dc->vmsd = &vmstate_gic;
372     albifc->arm_linux_init = arm_gic_common_linux_init;
373 }
374 
375 static const TypeInfo arm_gic_common_type = {
376     .name = TYPE_ARM_GIC_COMMON,
377     .parent = TYPE_SYS_BUS_DEVICE,
378     .instance_size = sizeof(GICState),
379     .class_size = sizeof(ARMGICCommonClass),
380     .class_init = arm_gic_common_class_init,
381     .abstract = true,
382     .interfaces = (InterfaceInfo []) {
383         { TYPE_ARM_LINUX_BOOT_IF },
384         { },
385     },
386 };
387 
388 static void register_types(void)
389 {
390     type_register_static(&arm_gic_common_type);
391 }
392 
393 type_init(register_types)
394