xref: /openbmc/qemu/hw/intc/arm_gic_common.c (revision 438c78da)
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 "gic_internal.h"
24 #include "hw/arm/linux-boot-if.h"
25 
26 static int gic_pre_save(void *opaque)
27 {
28     GICState *s = (GICState *)opaque;
29     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
30 
31     if (c->pre_save) {
32         c->pre_save(s);
33     }
34 
35     return 0;
36 }
37 
38 static int gic_post_load(void *opaque, int version_id)
39 {
40     GICState *s = (GICState *)opaque;
41     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
42 
43     if (c->post_load) {
44         c->post_load(s);
45     }
46     return 0;
47 }
48 
49 static bool gic_virt_state_needed(void *opaque)
50 {
51     GICState *s = (GICState *)opaque;
52 
53     return s->virt_extn;
54 }
55 
56 static const VMStateDescription vmstate_gic_irq_state = {
57     .name = "arm_gic_irq_state",
58     .version_id = 1,
59     .minimum_version_id = 1,
60     .fields = (VMStateField[]) {
61         VMSTATE_UINT8(enabled, gic_irq_state),
62         VMSTATE_UINT8(pending, gic_irq_state),
63         VMSTATE_UINT8(active, gic_irq_state),
64         VMSTATE_UINT8(level, gic_irq_state),
65         VMSTATE_BOOL(model, gic_irq_state),
66         VMSTATE_BOOL(edge_trigger, gic_irq_state),
67         VMSTATE_UINT8(group, gic_irq_state),
68         VMSTATE_END_OF_LIST()
69     }
70 };
71 
72 static const VMStateDescription vmstate_gic_virt_state = {
73     .name = "arm_gic_virt_state",
74     .version_id = 1,
75     .minimum_version_id = 1,
76     .needed = gic_virt_state_needed,
77     .fields = (VMStateField[]) {
78         /* Virtual interface */
79         VMSTATE_UINT32_ARRAY(h_hcr, GICState, GIC_NCPU),
80         VMSTATE_UINT32_ARRAY(h_misr, GICState, GIC_NCPU),
81         VMSTATE_UINT32_2DARRAY(h_lr, GICState, GIC_MAX_LR, GIC_NCPU),
82         VMSTATE_UINT32_ARRAY(h_apr, GICState, GIC_NCPU),
83 
84         /* Virtual CPU interfaces */
85         VMSTATE_UINT32_SUB_ARRAY(cpu_ctlr, GICState, GIC_NCPU, GIC_NCPU),
86         VMSTATE_UINT16_SUB_ARRAY(priority_mask, GICState, GIC_NCPU, GIC_NCPU),
87         VMSTATE_UINT16_SUB_ARRAY(running_priority, GICState, GIC_NCPU, GIC_NCPU),
88         VMSTATE_UINT16_SUB_ARRAY(current_pending, GICState, GIC_NCPU, GIC_NCPU),
89         VMSTATE_UINT8_SUB_ARRAY(bpr, GICState, GIC_NCPU, GIC_NCPU),
90         VMSTATE_UINT8_SUB_ARRAY(abpr, GICState, GIC_NCPU, GIC_NCPU),
91 
92         VMSTATE_END_OF_LIST()
93     }
94 };
95 
96 static const VMStateDescription vmstate_gic = {
97     .name = "arm_gic",
98     .version_id = 12,
99     .minimum_version_id = 12,
100     .pre_save = gic_pre_save,
101     .post_load = gic_post_load,
102     .fields = (VMStateField[]) {
103         VMSTATE_UINT32(ctlr, GICState),
104         VMSTATE_UINT32_SUB_ARRAY(cpu_ctlr, GICState, 0, GIC_NCPU),
105         VMSTATE_STRUCT_ARRAY(irq_state, GICState, GIC_MAXIRQ, 1,
106                              vmstate_gic_irq_state, gic_irq_state),
107         VMSTATE_UINT8_ARRAY(irq_target, GICState, GIC_MAXIRQ),
108         VMSTATE_UINT8_2DARRAY(priority1, GICState, GIC_INTERNAL, GIC_NCPU),
109         VMSTATE_UINT8_ARRAY(priority2, GICState, GIC_MAXIRQ - GIC_INTERNAL),
110         VMSTATE_UINT8_2DARRAY(sgi_pending, GICState, GIC_NR_SGIS, GIC_NCPU),
111         VMSTATE_UINT16_SUB_ARRAY(priority_mask, GICState, 0, GIC_NCPU),
112         VMSTATE_UINT16_SUB_ARRAY(running_priority, GICState, 0, GIC_NCPU),
113         VMSTATE_UINT16_SUB_ARRAY(current_pending, GICState, 0, GIC_NCPU),
114         VMSTATE_UINT8_SUB_ARRAY(bpr, GICState, 0, GIC_NCPU),
115         VMSTATE_UINT8_SUB_ARRAY(abpr, GICState, 0, GIC_NCPU),
116         VMSTATE_UINT32_2DARRAY(apr, GICState, GIC_NR_APRS, GIC_NCPU),
117         VMSTATE_UINT32_2DARRAY(nsapr, GICState, GIC_NR_APRS, GIC_NCPU),
118         VMSTATE_END_OF_LIST()
119     },
120     .subsections = (const VMStateDescription * []) {
121         &vmstate_gic_virt_state,
122         NULL
123     }
124 };
125 
126 void gic_init_irqs_and_mmio(GICState *s, qemu_irq_handler handler,
127                             const MemoryRegionOps *ops,
128                             const MemoryRegionOps *virt_ops)
129 {
130     SysBusDevice *sbd = SYS_BUS_DEVICE(s);
131     int i = s->num_irq - GIC_INTERNAL;
132 
133     /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
134      * GPIO array layout is thus:
135      *  [0..N-1] SPIs
136      *  [N..N+31] PPIs for CPU 0
137      *  [N+32..N+63] PPIs for CPU 1
138      *   ...
139      */
140     i += (GIC_INTERNAL * s->num_cpu);
141     qdev_init_gpio_in(DEVICE(s), handler, i);
142 
143     for (i = 0; i < s->num_cpu; i++) {
144         sysbus_init_irq(sbd, &s->parent_irq[i]);
145     }
146     for (i = 0; i < s->num_cpu; i++) {
147         sysbus_init_irq(sbd, &s->parent_fiq[i]);
148     }
149     for (i = 0; i < s->num_cpu; i++) {
150         sysbus_init_irq(sbd, &s->parent_virq[i]);
151     }
152     for (i = 0; i < s->num_cpu; i++) {
153         sysbus_init_irq(sbd, &s->parent_vfiq[i]);
154     }
155     if (s->virt_extn) {
156         for (i = 0; i < s->num_cpu; i++) {
157             sysbus_init_irq(sbd, &s->maintenance_irq[i]);
158         }
159     }
160 
161     /* Distributor */
162     memory_region_init_io(&s->iomem, OBJECT(s), ops, s, "gic_dist", 0x1000);
163     sysbus_init_mmio(sbd, &s->iomem);
164 
165     /* This is the main CPU interface "for this core". It is always
166      * present because it is required by both software emulation and KVM.
167      */
168     memory_region_init_io(&s->cpuiomem[0], OBJECT(s), ops ? &ops[1] : NULL,
169                           s, "gic_cpu", s->revision == 2 ? 0x2000 : 0x100);
170     sysbus_init_mmio(sbd, &s->cpuiomem[0]);
171 
172     if (s->virt_extn) {
173         memory_region_init_io(&s->vifaceiomem[0], OBJECT(s), virt_ops,
174                               s, "gic_viface", 0x1000);
175         sysbus_init_mmio(sbd, &s->vifaceiomem[0]);
176 
177         memory_region_init_io(&s->vcpuiomem, OBJECT(s),
178                               virt_ops ? &virt_ops[1] : NULL,
179                               s, "gic_vcpu", 0x2000);
180         sysbus_init_mmio(sbd, &s->vcpuiomem);
181     }
182 }
183 
184 static void arm_gic_common_realize(DeviceState *dev, Error **errp)
185 {
186     GICState *s = ARM_GIC_COMMON(dev);
187     int num_irq = s->num_irq;
188 
189     if (s->num_cpu > GIC_NCPU) {
190         error_setg(errp, "requested %u CPUs exceeds GIC maximum %d",
191                    s->num_cpu, GIC_NCPU);
192         return;
193     }
194     if (s->num_irq > GIC_MAXIRQ) {
195         error_setg(errp,
196                    "requested %u interrupt lines exceeds GIC maximum %d",
197                    num_irq, GIC_MAXIRQ);
198         return;
199     }
200     /* ITLinesNumber is represented as (N / 32) - 1 (see
201      * gic_dist_readb) so this is an implementation imposed
202      * restriction, not an architectural one:
203      */
204     if (s->num_irq < 32 || (s->num_irq % 32)) {
205         error_setg(errp,
206                    "%d interrupt lines unsupported: not divisible by 32",
207                    num_irq);
208         return;
209     }
210 
211     if (s->security_extn &&
212         (s->revision == REV_11MPCORE)) {
213         error_setg(errp, "this GIC revision does not implement "
214                    "the security extensions");
215         return;
216     }
217 
218     if (s->virt_extn) {
219         if (s->revision != 2) {
220             error_setg(errp, "GIC virtualization extensions are only "
221                        "supported by revision 2");
222             return;
223         }
224 
225         /* For now, set the number of implemented LRs to 4, as found in most
226          * real GICv2. This could be promoted as a QOM property if we need to
227          * emulate a variant with another num_lrs.
228          */
229         s->num_lrs = 4;
230     }
231 }
232 
233 static inline void arm_gic_common_reset_irq_state(GICState *s, int first_cpu,
234                                                   int resetprio)
235 {
236     int i, j;
237 
238     for (i = first_cpu; i < first_cpu + s->num_cpu; i++) {
239         if (s->revision == REV_11MPCORE) {
240             s->priority_mask[i] = 0xf0;
241         } else {
242             s->priority_mask[i] = resetprio;
243         }
244         s->current_pending[i] = 1023;
245         s->running_priority[i] = 0x100;
246         s->cpu_ctlr[i] = 0;
247         s->bpr[i] = gic_is_vcpu(i) ? GIC_VIRT_MIN_BPR : GIC_MIN_BPR;
248         s->abpr[i] = gic_is_vcpu(i) ? GIC_VIRT_MIN_ABPR : GIC_MIN_ABPR;
249 
250         if (!gic_is_vcpu(i)) {
251             for (j = 0; j < GIC_INTERNAL; j++) {
252                 s->priority1[j][i] = resetprio;
253             }
254             for (j = 0; j < GIC_NR_SGIS; j++) {
255                 s->sgi_pending[j][i] = 0;
256             }
257         }
258     }
259 }
260 
261 static void arm_gic_common_reset(DeviceState *dev)
262 {
263     GICState *s = ARM_GIC_COMMON(dev);
264     int i, j;
265     int resetprio;
266 
267     /* If we're resetting a TZ-aware GIC as if secure firmware
268      * had set it up ready to start a kernel in non-secure,
269      * we need to set interrupt priorities to a "zero for the
270      * NS view" value. This is particularly critical for the
271      * priority_mask[] values, because if they are zero then NS
272      * code cannot ever rewrite the priority to anything else.
273      */
274     if (s->security_extn && s->irq_reset_nonsecure) {
275         resetprio = 0x80;
276     } else {
277         resetprio = 0;
278     }
279 
280     memset(s->irq_state, 0, GIC_MAXIRQ * sizeof(gic_irq_state));
281     arm_gic_common_reset_irq_state(s, 0, resetprio);
282 
283     if (s->virt_extn) {
284         /* vCPU states are stored at indexes GIC_NCPU .. GIC_NCPU+num_cpu.
285          * The exposed vCPU interface does not have security extensions.
286          */
287         arm_gic_common_reset_irq_state(s, GIC_NCPU, 0);
288     }
289 
290     for (i = 0; i < GIC_NR_SGIS; i++) {
291         GIC_DIST_SET_ENABLED(i, ALL_CPU_MASK);
292         GIC_DIST_SET_EDGE_TRIGGER(i);
293     }
294 
295     for (i = 0; i < ARRAY_SIZE(s->priority2); i++) {
296         s->priority2[i] = resetprio;
297     }
298 
299     for (i = 0; i < GIC_MAXIRQ; i++) {
300         /* For uniprocessor GICs all interrupts always target the sole CPU */
301         if (s->num_cpu == 1) {
302             s->irq_target[i] = 1;
303         } else {
304             s->irq_target[i] = 0;
305         }
306     }
307     if (s->security_extn && s->irq_reset_nonsecure) {
308         for (i = 0; i < GIC_MAXIRQ; i++) {
309             GIC_DIST_SET_GROUP(i, ALL_CPU_MASK);
310         }
311     }
312 
313     if (s->virt_extn) {
314         for (i = 0; i < s->num_lrs; i++) {
315             for (j = 0; j < s->num_cpu; j++) {
316                 s->h_lr[i][j] = 0;
317             }
318         }
319 
320         for (i = 0; i < s->num_cpu; i++) {
321             s->h_hcr[i] = 0;
322             s->h_misr[i] = 0;
323         }
324     }
325 
326     s->ctlr = 0;
327 }
328 
329 static void arm_gic_common_linux_init(ARMLinuxBootIf *obj,
330                                       bool secure_boot)
331 {
332     GICState *s = ARM_GIC_COMMON(obj);
333 
334     if (s->security_extn && !secure_boot) {
335         /* We're directly booting a kernel into NonSecure. If this GIC
336          * implements the security extensions then we must configure it
337          * to have all the interrupts be NonSecure (this is a job that
338          * is done by the Secure boot firmware in real hardware, and in
339          * this mode QEMU is acting as a minimalist firmware-and-bootloader
340          * equivalent).
341          */
342         s->irq_reset_nonsecure = true;
343     }
344 }
345 
346 static Property arm_gic_common_properties[] = {
347     DEFINE_PROP_UINT32("num-cpu", GICState, num_cpu, 1),
348     DEFINE_PROP_UINT32("num-irq", GICState, num_irq, 32),
349     /* Revision can be 1 or 2 for GIC architecture specification
350      * versions 1 or 2, or 0 to indicate the legacy 11MPCore GIC.
351      */
352     DEFINE_PROP_UINT32("revision", GICState, revision, 1),
353     /* True if the GIC should implement the security extensions */
354     DEFINE_PROP_BOOL("has-security-extensions", GICState, security_extn, 0),
355     /* True if the GIC should implement the virtualization extensions */
356     DEFINE_PROP_BOOL("has-virtualization-extensions", GICState, virt_extn, 0),
357     DEFINE_PROP_END_OF_LIST(),
358 };
359 
360 static void arm_gic_common_class_init(ObjectClass *klass, void *data)
361 {
362     DeviceClass *dc = DEVICE_CLASS(klass);
363     ARMLinuxBootIfClass *albifc = ARM_LINUX_BOOT_IF_CLASS(klass);
364 
365     dc->reset = arm_gic_common_reset;
366     dc->realize = arm_gic_common_realize;
367     dc->props = arm_gic_common_properties;
368     dc->vmsd = &vmstate_gic;
369     albifc->arm_linux_init = arm_gic_common_linux_init;
370 }
371 
372 static const TypeInfo arm_gic_common_type = {
373     .name = TYPE_ARM_GIC_COMMON,
374     .parent = TYPE_SYS_BUS_DEVICE,
375     .instance_size = sizeof(GICState),
376     .class_size = sizeof(ARMGICCommonClass),
377     .class_init = arm_gic_common_class_init,
378     .abstract = true,
379     .interfaces = (InterfaceInfo []) {
380         { TYPE_ARM_LINUX_BOOT_IF },
381         { },
382     },
383 };
384 
385 static void register_types(void)
386 {
387     type_register_static(&arm_gic_common_type);
388 }
389 
390 type_init(register_types)
391