xref: /openbmc/qemu/hw/intc/arm_gic_common.c (revision b917da4c)
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 "gic_internal.h"
23 #include "hw/arm/linux-boot-if.h"
24 
25 static void gic_pre_save(void *opaque)
26 {
27     GICState *s = (GICState *)opaque;
28     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
29 
30     if (c->pre_save) {
31         c->pre_save(s);
32     }
33 }
34 
35 static int gic_post_load(void *opaque, int version_id)
36 {
37     GICState *s = (GICState *)opaque;
38     ARMGICCommonClass *c = ARM_GIC_COMMON_GET_CLASS(s);
39 
40     if (c->post_load) {
41         c->post_load(s);
42     }
43     return 0;
44 }
45 
46 static const VMStateDescription vmstate_gic_irq_state = {
47     .name = "arm_gic_irq_state",
48     .version_id = 1,
49     .minimum_version_id = 1,
50     .fields = (VMStateField[]) {
51         VMSTATE_UINT8(enabled, gic_irq_state),
52         VMSTATE_UINT8(pending, gic_irq_state),
53         VMSTATE_UINT8(active, gic_irq_state),
54         VMSTATE_UINT8(level, gic_irq_state),
55         VMSTATE_BOOL(model, gic_irq_state),
56         VMSTATE_BOOL(edge_trigger, gic_irq_state),
57         VMSTATE_UINT8(group, gic_irq_state),
58         VMSTATE_END_OF_LIST()
59     }
60 };
61 
62 static const VMStateDescription vmstate_gic = {
63     .name = "arm_gic",
64     .version_id = 12,
65     .minimum_version_id = 12,
66     .pre_save = gic_pre_save,
67     .post_load = gic_post_load,
68     .fields = (VMStateField[]) {
69         VMSTATE_UINT32(ctlr, GICState),
70         VMSTATE_UINT32_ARRAY(cpu_ctlr, GICState, GIC_NCPU),
71         VMSTATE_STRUCT_ARRAY(irq_state, GICState, GIC_MAXIRQ, 1,
72                              vmstate_gic_irq_state, gic_irq_state),
73         VMSTATE_UINT8_ARRAY(irq_target, GICState, GIC_MAXIRQ),
74         VMSTATE_UINT8_2DARRAY(priority1, GICState, GIC_INTERNAL, GIC_NCPU),
75         VMSTATE_UINT8_ARRAY(priority2, GICState, GIC_MAXIRQ - GIC_INTERNAL),
76         VMSTATE_UINT8_2DARRAY(sgi_pending, GICState, GIC_NR_SGIS, GIC_NCPU),
77         VMSTATE_UINT16_ARRAY(priority_mask, GICState, GIC_NCPU),
78         VMSTATE_UINT16_ARRAY(running_priority, GICState, GIC_NCPU),
79         VMSTATE_UINT16_ARRAY(current_pending, GICState, GIC_NCPU),
80         VMSTATE_UINT8_ARRAY(bpr, GICState, GIC_NCPU),
81         VMSTATE_UINT8_ARRAY(abpr, GICState, GIC_NCPU),
82         VMSTATE_UINT32_2DARRAY(apr, GICState, GIC_NR_APRS, GIC_NCPU),
83         VMSTATE_UINT32_2DARRAY(nsapr, GICState, GIC_NR_APRS, GIC_NCPU),
84         VMSTATE_END_OF_LIST()
85     }
86 };
87 
88 void gic_init_irqs_and_mmio(GICState *s, qemu_irq_handler handler,
89                             const MemoryRegionOps *ops)
90 {
91     SysBusDevice *sbd = SYS_BUS_DEVICE(s);
92     int i = s->num_irq - GIC_INTERNAL;
93 
94     /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
95      * GPIO array layout is thus:
96      *  [0..N-1] SPIs
97      *  [N..N+31] PPIs for CPU 0
98      *  [N+32..N+63] PPIs for CPU 1
99      *   ...
100      */
101     if (s->revision != REV_NVIC) {
102         i += (GIC_INTERNAL * s->num_cpu);
103     }
104     qdev_init_gpio_in(DEVICE(s), handler, i);
105 
106     for (i = 0; i < s->num_cpu; i++) {
107         sysbus_init_irq(sbd, &s->parent_irq[i]);
108     }
109     for (i = 0; i < s->num_cpu; i++) {
110         sysbus_init_irq(sbd, &s->parent_fiq[i]);
111     }
112 
113     /* Distributor */
114     memory_region_init_io(&s->iomem, OBJECT(s), ops, s, "gic_dist", 0x1000);
115     sysbus_init_mmio(sbd, &s->iomem);
116 
117     if (s->revision != REV_NVIC) {
118         /* This is the main CPU interface "for this core". It is always
119          * present because it is required by both software emulation and KVM.
120          * NVIC is not handled here because its CPU interface is different,
121          * neither it can use KVM.
122          */
123         memory_region_init_io(&s->cpuiomem[0], OBJECT(s), ops ? &ops[1] : NULL,
124                               s, "gic_cpu", s->revision == 2 ? 0x2000 : 0x100);
125         sysbus_init_mmio(sbd, &s->cpuiomem[0]);
126     }
127 }
128 
129 static void arm_gic_common_realize(DeviceState *dev, Error **errp)
130 {
131     GICState *s = ARM_GIC_COMMON(dev);
132     int num_irq = s->num_irq;
133 
134     if (s->num_cpu > GIC_NCPU) {
135         error_setg(errp, "requested %u CPUs exceeds GIC maximum %d",
136                    s->num_cpu, GIC_NCPU);
137         return;
138     }
139     s->num_irq += GIC_BASE_IRQ;
140     if (s->num_irq > GIC_MAXIRQ) {
141         error_setg(errp,
142                    "requested %u interrupt lines exceeds GIC maximum %d",
143                    num_irq, GIC_MAXIRQ);
144         return;
145     }
146     /* ITLinesNumber is represented as (N / 32) - 1 (see
147      * gic_dist_readb) so this is an implementation imposed
148      * restriction, not an architectural one:
149      */
150     if (s->num_irq < 32 || (s->num_irq % 32)) {
151         error_setg(errp,
152                    "%d interrupt lines unsupported: not divisible by 32",
153                    num_irq);
154         return;
155     }
156 
157     if (s->security_extn &&
158         (s->revision == REV_11MPCORE || s->revision == REV_NVIC)) {
159         error_setg(errp, "this GIC revision does not implement "
160                    "the security extensions");
161         return;
162     }
163 }
164 
165 static void arm_gic_common_reset(DeviceState *dev)
166 {
167     GICState *s = ARM_GIC_COMMON(dev);
168     int i, j;
169     int resetprio;
170 
171     /* If we're resetting a TZ-aware GIC as if secure firmware
172      * had set it up ready to start a kernel in non-secure,
173      * we need to set interrupt priorities to a "zero for the
174      * NS view" value. This is particularly critical for the
175      * priority_mask[] values, because if they are zero then NS
176      * code cannot ever rewrite the priority to anything else.
177      */
178     if (s->security_extn && s->irq_reset_nonsecure) {
179         resetprio = 0x80;
180     } else {
181         resetprio = 0;
182     }
183 
184     memset(s->irq_state, 0, GIC_MAXIRQ * sizeof(gic_irq_state));
185     for (i = 0 ; i < s->num_cpu; i++) {
186         if (s->revision == REV_11MPCORE) {
187             s->priority_mask[i] = 0xf0;
188         } else {
189             s->priority_mask[i] = resetprio;
190         }
191         s->current_pending[i] = 1023;
192         s->running_priority[i] = 0x100;
193         s->cpu_ctlr[i] = 0;
194         s->bpr[i] = GIC_MIN_BPR;
195         s->abpr[i] = GIC_MIN_ABPR;
196         for (j = 0; j < GIC_INTERNAL; j++) {
197             s->priority1[j][i] = resetprio;
198         }
199         for (j = 0; j < GIC_NR_SGIS; j++) {
200             s->sgi_pending[j][i] = 0;
201         }
202     }
203     for (i = 0; i < GIC_NR_SGIS; i++) {
204         GIC_SET_ENABLED(i, ALL_CPU_MASK);
205         GIC_SET_EDGE_TRIGGER(i);
206     }
207 
208     for (i = 0; i < ARRAY_SIZE(s->priority2); i++) {
209         s->priority2[i] = resetprio;
210     }
211 
212     for (i = 0; i < GIC_MAXIRQ; i++) {
213         /* For uniprocessor GICs all interrupts always target the sole CPU */
214         if (s->num_cpu == 1) {
215             s->irq_target[i] = 1;
216         } else {
217             s->irq_target[i] = 0;
218         }
219     }
220     if (s->security_extn && s->irq_reset_nonsecure) {
221         for (i = 0; i < GIC_MAXIRQ; i++) {
222             GIC_SET_GROUP(i, ALL_CPU_MASK);
223         }
224     }
225 
226     s->ctlr = 0;
227 }
228 
229 static void arm_gic_common_linux_init(ARMLinuxBootIf *obj,
230                                       bool secure_boot)
231 {
232     GICState *s = ARM_GIC_COMMON(obj);
233 
234     if (s->security_extn && !secure_boot) {
235         /* We're directly booting a kernel into NonSecure. If this GIC
236          * implements the security extensions then we must configure it
237          * to have all the interrupts be NonSecure (this is a job that
238          * is done by the Secure boot firmware in real hardware, and in
239          * this mode QEMU is acting as a minimalist firmware-and-bootloader
240          * equivalent).
241          */
242         s->irq_reset_nonsecure = true;
243     }
244 }
245 
246 static Property arm_gic_common_properties[] = {
247     DEFINE_PROP_UINT32("num-cpu", GICState, num_cpu, 1),
248     DEFINE_PROP_UINT32("num-irq", GICState, num_irq, 32),
249     /* Revision can be 1 or 2 for GIC architecture specification
250      * versions 1 or 2, or 0 to indicate the legacy 11MPCore GIC.
251      * (Internally, 0xffffffff also indicates "not a GIC but an NVIC".)
252      */
253     DEFINE_PROP_UINT32("revision", GICState, revision, 1),
254     /* True if the GIC should implement the security extensions */
255     DEFINE_PROP_BOOL("has-security-extensions", GICState, security_extn, 0),
256     DEFINE_PROP_END_OF_LIST(),
257 };
258 
259 static void arm_gic_common_class_init(ObjectClass *klass, void *data)
260 {
261     DeviceClass *dc = DEVICE_CLASS(klass);
262     ARMLinuxBootIfClass *albifc = ARM_LINUX_BOOT_IF_CLASS(klass);
263 
264     dc->reset = arm_gic_common_reset;
265     dc->realize = arm_gic_common_realize;
266     dc->props = arm_gic_common_properties;
267     dc->vmsd = &vmstate_gic;
268     albifc->arm_linux_init = arm_gic_common_linux_init;
269 }
270 
271 static const TypeInfo arm_gic_common_type = {
272     .name = TYPE_ARM_GIC_COMMON,
273     .parent = TYPE_SYS_BUS_DEVICE,
274     .instance_size = sizeof(GICState),
275     .class_size = sizeof(ARMGICCommonClass),
276     .class_init = arm_gic_common_class_init,
277     .abstract = true,
278     .interfaces = (InterfaceInfo []) {
279         { TYPE_ARM_LINUX_BOOT_IF },
280         { },
281     },
282 };
283 
284 static void register_types(void)
285 {
286     type_register_static(&arm_gic_common_type);
287 }
288 
289 type_init(register_types)
290