xref: /openbmc/qemu/hw/intc/arm_gic_common.c (revision 8e6fe6b8)
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 
27 static int gic_pre_save(void *opaque)
28 {
29     GICState *s = (GICState *)opaque;
30     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
31 
32     if (c->pre_save) {
33         c->pre_save(s);
34     }
35 
36     return 0;
37 }
38 
39 static int gic_post_load(void *opaque, int version_id)
40 {
41     GICState *s = (GICState *)opaque;
42     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
43 
44     if (c->post_load) {
45         c->post_load(s);
46     }
47     return 0;
48 }
49 
50 static bool gic_virt_state_needed(void *opaque)
51 {
52     GICState *s = (GICState *)opaque;
53 
54     return s->virt_extn;
55 }
56 
57 static const VMStateDescription vmstate_gic_irq_state = {
58     .name = "arm_gic_irq_state",
59     .version_id = 1,
60     .minimum_version_id = 1,
61     .fields = (VMStateField[]) {
62         VMSTATE_UINT8(enabled, gic_irq_state),
63         VMSTATE_UINT8(pending, gic_irq_state),
64         VMSTATE_UINT8(active, gic_irq_state),
65         VMSTATE_UINT8(level, gic_irq_state),
66         VMSTATE_BOOL(model, gic_irq_state),
67         VMSTATE_BOOL(edge_trigger, gic_irq_state),
68         VMSTATE_UINT8(group, gic_irq_state),
69         VMSTATE_END_OF_LIST()
70     }
71 };
72 
73 static const VMStateDescription vmstate_gic_virt_state = {
74     .name = "arm_gic_virt_state",
75     .version_id = 1,
76     .minimum_version_id = 1,
77     .needed = gic_virt_state_needed,
78     .fields = (VMStateField[]) {
79         /* Virtual interface */
80         VMSTATE_UINT32_ARRAY(h_hcr, GICState, GIC_NCPU),
81         VMSTATE_UINT32_ARRAY(h_misr, GICState, GIC_NCPU),
82         VMSTATE_UINT32_2DARRAY(h_lr, GICState, GIC_MAX_LR, GIC_NCPU),
83         VMSTATE_UINT32_ARRAY(h_apr, GICState, GIC_NCPU),
84 
85         /* Virtual CPU interfaces */
86         VMSTATE_UINT32_SUB_ARRAY(cpu_ctlr, GICState, GIC_NCPU, GIC_NCPU),
87         VMSTATE_UINT16_SUB_ARRAY(priority_mask, GICState, GIC_NCPU, GIC_NCPU),
88         VMSTATE_UINT16_SUB_ARRAY(running_priority, GICState, GIC_NCPU, GIC_NCPU),
89         VMSTATE_UINT16_SUB_ARRAY(current_pending, GICState, GIC_NCPU, GIC_NCPU),
90         VMSTATE_UINT8_SUB_ARRAY(bpr, GICState, GIC_NCPU, GIC_NCPU),
91         VMSTATE_UINT8_SUB_ARRAY(abpr, GICState, GIC_NCPU, GIC_NCPU),
92 
93         VMSTATE_END_OF_LIST()
94     }
95 };
96 
97 static const VMStateDescription vmstate_gic = {
98     .name = "arm_gic",
99     .version_id = 12,
100     .minimum_version_id = 12,
101     .pre_save = gic_pre_save,
102     .post_load = gic_post_load,
103     .fields = (VMStateField[]) {
104         VMSTATE_UINT32(ctlr, GICState),
105         VMSTATE_UINT32_SUB_ARRAY(cpu_ctlr, GICState, 0, GIC_NCPU),
106         VMSTATE_STRUCT_ARRAY(irq_state, GICState, GIC_MAXIRQ, 1,
107                              vmstate_gic_irq_state, gic_irq_state),
108         VMSTATE_UINT8_ARRAY(irq_target, GICState, GIC_MAXIRQ),
109         VMSTATE_UINT8_2DARRAY(priority1, GICState, GIC_INTERNAL, GIC_NCPU),
110         VMSTATE_UINT8_ARRAY(priority2, GICState, GIC_MAXIRQ - GIC_INTERNAL),
111         VMSTATE_UINT8_2DARRAY(sgi_pending, GICState, GIC_NR_SGIS, GIC_NCPU),
112         VMSTATE_UINT16_SUB_ARRAY(priority_mask, GICState, 0, GIC_NCPU),
113         VMSTATE_UINT16_SUB_ARRAY(running_priority, GICState, 0, GIC_NCPU),
114         VMSTATE_UINT16_SUB_ARRAY(current_pending, GICState, 0, GIC_NCPU),
115         VMSTATE_UINT8_SUB_ARRAY(bpr, GICState, 0, GIC_NCPU),
116         VMSTATE_UINT8_SUB_ARRAY(abpr, GICState, 0, GIC_NCPU),
117         VMSTATE_UINT32_2DARRAY(apr, GICState, GIC_NR_APRS, GIC_NCPU),
118         VMSTATE_UINT32_2DARRAY(nsapr, GICState, GIC_NR_APRS, GIC_NCPU),
119         VMSTATE_END_OF_LIST()
120     },
121     .subsections = (const VMStateDescription * []) {
122         &vmstate_gic_virt_state,
123         NULL
124     }
125 };
126 
127 void gic_init_irqs_and_mmio(GICState *s, qemu_irq_handler handler,
128                             const MemoryRegionOps *ops,
129                             const MemoryRegionOps *virt_ops)
130 {
131     SysBusDevice *sbd = SYS_BUS_DEVICE(s);
132     int i = s->num_irq - GIC_INTERNAL;
133 
134     /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
135      * GPIO array layout is thus:
136      *  [0..N-1] SPIs
137      *  [N..N+31] PPIs for CPU 0
138      *  [N+32..N+63] PPIs for CPU 1
139      *   ...
140      */
141     i += (GIC_INTERNAL * s->num_cpu);
142     qdev_init_gpio_in(DEVICE(s), handler, i);
143 
144     for (i = 0; i < s->num_cpu; i++) {
145         sysbus_init_irq(sbd, &s->parent_irq[i]);
146     }
147     for (i = 0; i < s->num_cpu; i++) {
148         sysbus_init_irq(sbd, &s->parent_fiq[i]);
149     }
150     for (i = 0; i < s->num_cpu; i++) {
151         sysbus_init_irq(sbd, &s->parent_virq[i]);
152     }
153     for (i = 0; i < s->num_cpu; i++) {
154         sysbus_init_irq(sbd, &s->parent_vfiq[i]);
155     }
156     if (s->virt_extn) {
157         for (i = 0; i < s->num_cpu; i++) {
158             sysbus_init_irq(sbd, &s->maintenance_irq[i]);
159         }
160     }
161 
162     /* Distributor */
163     memory_region_init_io(&s->iomem, OBJECT(s), ops, s, "gic_dist", 0x1000);
164     sysbus_init_mmio(sbd, &s->iomem);
165 
166     /* This is the main CPU interface "for this core". It is always
167      * present because it is required by both software emulation and KVM.
168      */
169     memory_region_init_io(&s->cpuiomem[0], OBJECT(s), ops ? &ops[1] : NULL,
170                           s, "gic_cpu", s->revision == 2 ? 0x2000 : 0x100);
171     sysbus_init_mmio(sbd, &s->cpuiomem[0]);
172 
173     if (s->virt_extn) {
174         memory_region_init_io(&s->vifaceiomem[0], OBJECT(s), virt_ops,
175                               s, "gic_viface", 0x1000);
176         sysbus_init_mmio(sbd, &s->vifaceiomem[0]);
177 
178         memory_region_init_io(&s->vcpuiomem, OBJECT(s),
179                               virt_ops ? &virt_ops[1] : NULL,
180                               s, "gic_vcpu", 0x2000);
181         sysbus_init_mmio(sbd, &s->vcpuiomem);
182     }
183 }
184 
185 static void arm_gic_common_realize(DeviceState *dev, Error **errp)
186 {
187     GICState *s = ARM_GIC_COMMON(dev);
188     int num_irq = s->num_irq;
189 
190     if (s->num_cpu > GIC_NCPU) {
191         error_setg(errp, "requested %u CPUs exceeds GIC maximum %d",
192                    s->num_cpu, GIC_NCPU);
193         return;
194     }
195     if (s->num_irq > GIC_MAXIRQ) {
196         error_setg(errp,
197                    "requested %u interrupt lines exceeds GIC maximum %d",
198                    num_irq, GIC_MAXIRQ);
199         return;
200     }
201     /* ITLinesNumber is represented as (N / 32) - 1 (see
202      * gic_dist_readb) so this is an implementation imposed
203      * restriction, not an architectural one:
204      */
205     if (s->num_irq < 32 || (s->num_irq % 32)) {
206         error_setg(errp,
207                    "%d interrupt lines unsupported: not divisible by 32",
208                    num_irq);
209         return;
210     }
211 
212     if (s->security_extn &&
213         (s->revision == REV_11MPCORE)) {
214         error_setg(errp, "this GIC revision does not implement "
215                    "the security extensions");
216         return;
217     }
218 
219     if (s->virt_extn) {
220         if (s->revision != 2) {
221             error_setg(errp, "GIC virtualization extensions are only "
222                        "supported by revision 2");
223             return;
224         }
225 
226         /* For now, set the number of implemented LRs to 4, as found in most
227          * real GICv2. This could be promoted as a QOM property if we need to
228          * emulate a variant with another num_lrs.
229          */
230         s->num_lrs = 4;
231     }
232 }
233 
234 static inline void arm_gic_common_reset_irq_state(GICState *s, int first_cpu,
235                                                   int resetprio)
236 {
237     int i, j;
238 
239     for (i = first_cpu; i < first_cpu + s->num_cpu; i++) {
240         if (s->revision == REV_11MPCORE) {
241             s->priority_mask[i] = 0xf0;
242         } else {
243             s->priority_mask[i] = resetprio;
244         }
245         s->current_pending[i] = 1023;
246         s->running_priority[i] = 0x100;
247         s->cpu_ctlr[i] = 0;
248         s->bpr[i] = gic_is_vcpu(i) ? GIC_VIRT_MIN_BPR : GIC_MIN_BPR;
249         s->abpr[i] = gic_is_vcpu(i) ? GIC_VIRT_MIN_ABPR : GIC_MIN_ABPR;
250 
251         if (!gic_is_vcpu(i)) {
252             for (j = 0; j < GIC_INTERNAL; j++) {
253                 s->priority1[j][i] = resetprio;
254             }
255             for (j = 0; j < GIC_NR_SGIS; j++) {
256                 s->sgi_pending[j][i] = 0;
257             }
258         }
259     }
260 }
261 
262 static void arm_gic_common_reset(DeviceState *dev)
263 {
264     GICState *s = ARM_GIC_COMMON(dev);
265     int i, j;
266     int resetprio;
267 
268     /* If we're resetting a TZ-aware GIC as if secure firmware
269      * had set it up ready to start a kernel in non-secure,
270      * we need to set interrupt priorities to a "zero for the
271      * NS view" value. This is particularly critical for the
272      * priority_mask[] values, because if they are zero then NS
273      * code cannot ever rewrite the priority to anything else.
274      */
275     if (s->security_extn && s->irq_reset_nonsecure) {
276         resetprio = 0x80;
277     } else {
278         resetprio = 0;
279     }
280 
281     memset(s->irq_state, 0, GIC_MAXIRQ * sizeof(gic_irq_state));
282     arm_gic_common_reset_irq_state(s, 0, resetprio);
283 
284     if (s->virt_extn) {
285         /* vCPU states are stored at indexes GIC_NCPU .. GIC_NCPU+num_cpu.
286          * The exposed vCPU interface does not have security extensions.
287          */
288         arm_gic_common_reset_irq_state(s, GIC_NCPU, 0);
289     }
290 
291     for (i = 0; i < GIC_NR_SGIS; i++) {
292         GIC_DIST_SET_ENABLED(i, ALL_CPU_MASK);
293         GIC_DIST_SET_EDGE_TRIGGER(i);
294     }
295 
296     for (i = 0; i < ARRAY_SIZE(s->priority2); i++) {
297         s->priority2[i] = resetprio;
298     }
299 
300     for (i = 0; i < GIC_MAXIRQ; i++) {
301         /* For uniprocessor GICs all interrupts always target the sole CPU */
302         if (s->num_cpu == 1) {
303             s->irq_target[i] = 1;
304         } else {
305             s->irq_target[i] = 0;
306         }
307     }
308     if (s->security_extn && s->irq_reset_nonsecure) {
309         for (i = 0; i < GIC_MAXIRQ; i++) {
310             GIC_DIST_SET_GROUP(i, ALL_CPU_MASK);
311         }
312     }
313 
314     if (s->virt_extn) {
315         for (i = 0; i < s->num_lrs; i++) {
316             for (j = 0; j < s->num_cpu; j++) {
317                 s->h_lr[i][j] = 0;
318             }
319         }
320 
321         for (i = 0; i < s->num_cpu; i++) {
322             s->h_hcr[i] = 0;
323             s->h_misr[i] = 0;
324         }
325     }
326 
327     s->ctlr = 0;
328 }
329 
330 static void arm_gic_common_linux_init(ARMLinuxBootIf *obj,
331                                       bool secure_boot)
332 {
333     GICState *s = ARM_GIC_COMMON(obj);
334 
335     if (s->security_extn && !secure_boot) {
336         /* We're directly booting a kernel into NonSecure. If this GIC
337          * implements the security extensions then we must configure it
338          * to have all the interrupts be NonSecure (this is a job that
339          * is done by the Secure boot firmware in real hardware, and in
340          * this mode QEMU is acting as a minimalist firmware-and-bootloader
341          * equivalent).
342          */
343         s->irq_reset_nonsecure = true;
344     }
345 }
346 
347 static Property arm_gic_common_properties[] = {
348     DEFINE_PROP_UINT32("num-cpu", GICState, num_cpu, 1),
349     DEFINE_PROP_UINT32("num-irq", GICState, num_irq, 32),
350     /* Revision can be 1 or 2 for GIC architecture specification
351      * versions 1 or 2, or 0 to indicate the legacy 11MPCore GIC.
352      */
353     DEFINE_PROP_UINT32("revision", GICState, revision, 1),
354     /* True if the GIC should implement the security extensions */
355     DEFINE_PROP_BOOL("has-security-extensions", GICState, security_extn, 0),
356     /* True if the GIC should implement the virtualization extensions */
357     DEFINE_PROP_BOOL("has-virtualization-extensions", GICState, virt_extn, 0),
358     DEFINE_PROP_END_OF_LIST(),
359 };
360 
361 static void arm_gic_common_class_init(ObjectClass *klass, void *data)
362 {
363     DeviceClass *dc = DEVICE_CLASS(klass);
364     ARMLinuxBootIfClass *albifc = ARM_LINUX_BOOT_IF_CLASS(klass);
365 
366     dc->reset = arm_gic_common_reset;
367     dc->realize = arm_gic_common_realize;
368     dc->props = arm_gic_common_properties;
369     dc->vmsd = &vmstate_gic;
370     albifc->arm_linux_init = arm_gic_common_linux_init;
371 }
372 
373 static const TypeInfo arm_gic_common_type = {
374     .name = TYPE_ARM_GIC_COMMON,
375     .parent = TYPE_SYS_BUS_DEVICE,
376     .instance_size = sizeof(GICState),
377     .class_size = sizeof(ARMGICCommonClass),
378     .class_init = arm_gic_common_class_init,
379     .abstract = true,
380     .interfaces = (InterfaceInfo []) {
381         { TYPE_ARM_LINUX_BOOT_IF },
382         { },
383     },
384 };
385 
386 static void register_types(void)
387 {
388     type_register_static(&arm_gic_common_type);
389 }
390 
391 type_init(register_types)
392