xref: /openbmc/qemu/hw/intc/arm_gic_common.c (revision dc5bd18f)
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 const VMStateDescription vmstate_gic_irq_state = {
50     .name = "arm_gic_irq_state",
51     .version_id = 1,
52     .minimum_version_id = 1,
53     .fields = (VMStateField[]) {
54         VMSTATE_UINT8(enabled, gic_irq_state),
55         VMSTATE_UINT8(pending, gic_irq_state),
56         VMSTATE_UINT8(active, gic_irq_state),
57         VMSTATE_UINT8(level, gic_irq_state),
58         VMSTATE_BOOL(model, gic_irq_state),
59         VMSTATE_BOOL(edge_trigger, gic_irq_state),
60         VMSTATE_UINT8(group, gic_irq_state),
61         VMSTATE_END_OF_LIST()
62     }
63 };
64 
65 static const VMStateDescription vmstate_gic = {
66     .name = "arm_gic",
67     .version_id = 12,
68     .minimum_version_id = 12,
69     .pre_save = gic_pre_save,
70     .post_load = gic_post_load,
71     .fields = (VMStateField[]) {
72         VMSTATE_UINT32(ctlr, GICState),
73         VMSTATE_UINT32_ARRAY(cpu_ctlr, GICState, GIC_NCPU),
74         VMSTATE_STRUCT_ARRAY(irq_state, GICState, GIC_MAXIRQ, 1,
75                              vmstate_gic_irq_state, gic_irq_state),
76         VMSTATE_UINT8_ARRAY(irq_target, GICState, GIC_MAXIRQ),
77         VMSTATE_UINT8_2DARRAY(priority1, GICState, GIC_INTERNAL, GIC_NCPU),
78         VMSTATE_UINT8_ARRAY(priority2, GICState, GIC_MAXIRQ - GIC_INTERNAL),
79         VMSTATE_UINT8_2DARRAY(sgi_pending, GICState, GIC_NR_SGIS, GIC_NCPU),
80         VMSTATE_UINT16_ARRAY(priority_mask, GICState, GIC_NCPU),
81         VMSTATE_UINT16_ARRAY(running_priority, GICState, GIC_NCPU),
82         VMSTATE_UINT16_ARRAY(current_pending, GICState, GIC_NCPU),
83         VMSTATE_UINT8_ARRAY(bpr, GICState, GIC_NCPU),
84         VMSTATE_UINT8_ARRAY(abpr, GICState, GIC_NCPU),
85         VMSTATE_UINT32_2DARRAY(apr, GICState, GIC_NR_APRS, GIC_NCPU),
86         VMSTATE_UINT32_2DARRAY(nsapr, GICState, GIC_NR_APRS, GIC_NCPU),
87         VMSTATE_END_OF_LIST()
88     }
89 };
90 
91 void gic_init_irqs_and_mmio(GICState *s, qemu_irq_handler handler,
92                             const MemoryRegionOps *ops)
93 {
94     SysBusDevice *sbd = SYS_BUS_DEVICE(s);
95     int i = s->num_irq - GIC_INTERNAL;
96 
97     /* For the GIC, also expose incoming GPIO lines for PPIs for each CPU.
98      * GPIO array layout is thus:
99      *  [0..N-1] SPIs
100      *  [N..N+31] PPIs for CPU 0
101      *  [N+32..N+63] PPIs for CPU 1
102      *   ...
103      */
104     i += (GIC_INTERNAL * s->num_cpu);
105     qdev_init_gpio_in(DEVICE(s), handler, i);
106 
107     for (i = 0; i < s->num_cpu; i++) {
108         sysbus_init_irq(sbd, &s->parent_irq[i]);
109     }
110     for (i = 0; i < s->num_cpu; i++) {
111         sysbus_init_irq(sbd, &s->parent_fiq[i]);
112     }
113     for (i = 0; i < s->num_cpu; i++) {
114         sysbus_init_irq(sbd, &s->parent_virq[i]);
115     }
116     for (i = 0; i < s->num_cpu; i++) {
117         sysbus_init_irq(sbd, &s->parent_vfiq[i]);
118     }
119 
120     /* Distributor */
121     memory_region_init_io(&s->iomem, OBJECT(s), ops, s, "gic_dist", 0x1000);
122     sysbus_init_mmio(sbd, &s->iomem);
123 
124     /* This is the main CPU interface "for this core". It is always
125      * present because it is required by both software emulation and KVM.
126      */
127     memory_region_init_io(&s->cpuiomem[0], OBJECT(s), ops ? &ops[1] : NULL,
128                           s, "gic_cpu", s->revision == 2 ? 0x2000 : 0x100);
129     sysbus_init_mmio(sbd, &s->cpuiomem[0]);
130 }
131 
132 static void arm_gic_common_realize(DeviceState *dev, Error **errp)
133 {
134     GICState *s = ARM_GIC_COMMON(dev);
135     int num_irq = s->num_irq;
136 
137     if (s->num_cpu > GIC_NCPU) {
138         error_setg(errp, "requested %u CPUs exceeds GIC maximum %d",
139                    s->num_cpu, GIC_NCPU);
140         return;
141     }
142     s->num_irq += GIC_BASE_IRQ;
143     if (s->num_irq > GIC_MAXIRQ) {
144         error_setg(errp,
145                    "requested %u interrupt lines exceeds GIC maximum %d",
146                    num_irq, GIC_MAXIRQ);
147         return;
148     }
149     /* ITLinesNumber is represented as (N / 32) - 1 (see
150      * gic_dist_readb) so this is an implementation imposed
151      * restriction, not an architectural one:
152      */
153     if (s->num_irq < 32 || (s->num_irq % 32)) {
154         error_setg(errp,
155                    "%d interrupt lines unsupported: not divisible by 32",
156                    num_irq);
157         return;
158     }
159 
160     if (s->security_extn &&
161         (s->revision == REV_11MPCORE)) {
162         error_setg(errp, "this GIC revision does not implement "
163                    "the security extensions");
164         return;
165     }
166 }
167 
168 static void arm_gic_common_reset(DeviceState *dev)
169 {
170     GICState *s = ARM_GIC_COMMON(dev);
171     int i, j;
172     int resetprio;
173 
174     /* If we're resetting a TZ-aware GIC as if secure firmware
175      * had set it up ready to start a kernel in non-secure,
176      * we need to set interrupt priorities to a "zero for the
177      * NS view" value. This is particularly critical for the
178      * priority_mask[] values, because if they are zero then NS
179      * code cannot ever rewrite the priority to anything else.
180      */
181     if (s->security_extn && s->irq_reset_nonsecure) {
182         resetprio = 0x80;
183     } else {
184         resetprio = 0;
185     }
186 
187     memset(s->irq_state, 0, GIC_MAXIRQ * sizeof(gic_irq_state));
188     for (i = 0 ; i < s->num_cpu; i++) {
189         if (s->revision == REV_11MPCORE) {
190             s->priority_mask[i] = 0xf0;
191         } else {
192             s->priority_mask[i] = resetprio;
193         }
194         s->current_pending[i] = 1023;
195         s->running_priority[i] = 0x100;
196         s->cpu_ctlr[i] = 0;
197         s->bpr[i] = GIC_MIN_BPR;
198         s->abpr[i] = GIC_MIN_ABPR;
199         for (j = 0; j < GIC_INTERNAL; j++) {
200             s->priority1[j][i] = resetprio;
201         }
202         for (j = 0; j < GIC_NR_SGIS; j++) {
203             s->sgi_pending[j][i] = 0;
204         }
205     }
206     for (i = 0; i < GIC_NR_SGIS; i++) {
207         GIC_SET_ENABLED(i, ALL_CPU_MASK);
208         GIC_SET_EDGE_TRIGGER(i);
209     }
210 
211     for (i = 0; i < ARRAY_SIZE(s->priority2); i++) {
212         s->priority2[i] = resetprio;
213     }
214 
215     for (i = 0; i < GIC_MAXIRQ; i++) {
216         /* For uniprocessor GICs all interrupts always target the sole CPU */
217         if (s->num_cpu == 1) {
218             s->irq_target[i] = 1;
219         } else {
220             s->irq_target[i] = 0;
221         }
222     }
223     if (s->security_extn && s->irq_reset_nonsecure) {
224         for (i = 0; i < GIC_MAXIRQ; i++) {
225             GIC_SET_GROUP(i, ALL_CPU_MASK);
226         }
227     }
228 
229     s->ctlr = 0;
230 }
231 
232 static void arm_gic_common_linux_init(ARMLinuxBootIf *obj,
233                                       bool secure_boot)
234 {
235     GICState *s = ARM_GIC_COMMON(obj);
236 
237     if (s->security_extn && !secure_boot) {
238         /* We're directly booting a kernel into NonSecure. If this GIC
239          * implements the security extensions then we must configure it
240          * to have all the interrupts be NonSecure (this is a job that
241          * is done by the Secure boot firmware in real hardware, and in
242          * this mode QEMU is acting as a minimalist firmware-and-bootloader
243          * equivalent).
244          */
245         s->irq_reset_nonsecure = true;
246     }
247 }
248 
249 static Property arm_gic_common_properties[] = {
250     DEFINE_PROP_UINT32("num-cpu", GICState, num_cpu, 1),
251     DEFINE_PROP_UINT32("num-irq", GICState, num_irq, 32),
252     /* Revision can be 1 or 2 for GIC architecture specification
253      * versions 1 or 2, or 0 to indicate the legacy 11MPCore GIC.
254      */
255     DEFINE_PROP_UINT32("revision", GICState, revision, 1),
256     /* True if the GIC should implement the security extensions */
257     DEFINE_PROP_BOOL("has-security-extensions", GICState, security_extn, 0),
258     DEFINE_PROP_END_OF_LIST(),
259 };
260 
261 static void arm_gic_common_class_init(ObjectClass *klass, void *data)
262 {
263     DeviceClass *dc = DEVICE_CLASS(klass);
264     ARMLinuxBootIfClass *albifc = ARM_LINUX_BOOT_IF_CLASS(klass);
265 
266     dc->reset = arm_gic_common_reset;
267     dc->realize = arm_gic_common_realize;
268     dc->props = arm_gic_common_properties;
269     dc->vmsd = &vmstate_gic;
270     albifc->arm_linux_init = arm_gic_common_linux_init;
271 }
272 
273 static const TypeInfo arm_gic_common_type = {
274     .name = TYPE_ARM_GIC_COMMON,
275     .parent = TYPE_SYS_BUS_DEVICE,
276     .instance_size = sizeof(GICState),
277     .class_size = sizeof(ARMGICCommonClass),
278     .class_init = arm_gic_common_class_init,
279     .abstract = true,
280     .interfaces = (InterfaceInfo []) {
281         { TYPE_ARM_LINUX_BOOT_IF },
282         { },
283     },
284 };
285 
286 static void register_types(void)
287 {
288     type_register_static(&arm_gic_common_type);
289 }
290 
291 type_init(register_types)
292