Add safety net against potential infinite loop
[qemu-kvm/fedora.git] / hw / mpcore.c
blobd5b28fe4bd0412178c551d1aaddd920814c5b8c9
1 /*
2 * ARM MPCore internal peripheral emulation.
4 * Copyright (c) 2006-2007 CodeSourcery.
5 * Written by Paul Brook
7 * This code is licenced under the GPL.
8 */
10 #include "hw.h"
11 #include "qemu-timer.h"
12 #include "primecell.h"
14 #define MPCORE_PRIV_BASE 0x10100000
15 #define NCPU 4
16 /* ??? The MPCore TRM says the on-chip controller has 224 external IRQ lines
17 (+ 32 internal). However my test chip only exposes/reports 32.
18 More importantly Linux falls over if more than 32 are present! */
19 #define GIC_NIRQ 64
21 static inline int
22 gic_get_current_cpu(void)
24 return cpu_single_env->cpu_index;
27 #include "arm_gic.c"
29 /* MPCore private memory region. */
31 typedef struct {
32 uint32_t count;
33 uint32_t load;
34 uint32_t control;
35 uint32_t status;
36 uint32_t old_status;
37 int64_t tick;
38 QEMUTimer *timer;
39 struct mpcore_priv_state *mpcore;
40 int id; /* Encodes both timer/watchdog and CPU. */
41 } mpcore_timer_state;
43 typedef struct mpcore_priv_state {
44 gic_state *gic;
45 uint32_t scu_control;
46 mpcore_timer_state timer[8];
47 } mpcore_priv_state;
49 /* Per-CPU Timers. */
51 static inline void mpcore_timer_update_irq(mpcore_timer_state *s)
53 if (s->status & ~s->old_status) {
54 gic_set_pending_private(s->mpcore->gic, s->id >> 1, 29 + (s->id & 1));
56 s->old_status = s->status;
59 /* Return conversion factor from mpcore timer ticks to qemu timer ticks. */
60 static inline uint32_t mpcore_timer_scale(mpcore_timer_state *s)
62 return (((s->control >> 8) & 0xff) + 1) * 10;
65 static void mpcore_timer_reload(mpcore_timer_state *s, int restart)
67 if (s->count == 0)
68 return;
69 if (restart)
70 s->tick = qemu_get_clock(vm_clock);
71 s->tick += (int64_t)s->count * mpcore_timer_scale(s);
72 qemu_mod_timer(s->timer, s->tick);
75 static void mpcore_timer_tick(void *opaque)
77 mpcore_timer_state *s = (mpcore_timer_state *)opaque;
78 s->status = 1;
79 if (s->control & 2) {
80 s->count = s->load;
81 mpcore_timer_reload(s, 0);
82 } else {
83 s->count = 0;
85 mpcore_timer_update_irq(s);
88 static uint32_t mpcore_timer_read(mpcore_timer_state *s, int offset)
90 int64_t val;
91 switch (offset) {
92 case 0: /* Load */
93 return s->load;
94 /* Fall through. */
95 case 4: /* Counter. */
96 if (((s->control & 1) == 0) || (s->count == 0))
97 return 0;
98 /* Slow and ugly, but hopefully won't happen too often. */
99 val = s->tick - qemu_get_clock(vm_clock);
100 val /= mpcore_timer_scale(s);
101 if (val < 0)
102 val = 0;
103 return val;
104 case 8: /* Control. */
105 return s->control;
106 case 12: /* Interrupt status. */
107 return s->status;
111 static void mpcore_timer_write(mpcore_timer_state *s, int offset,
112 uint32_t value)
114 int64_t old;
115 switch (offset) {
116 case 0: /* Load */
117 s->load = value;
118 /* Fall through. */
119 case 4: /* Counter. */
120 if ((s->control & 1) && s->count) {
121 /* Cancel the previous timer. */
122 qemu_del_timer(s->timer);
124 s->count = value;
125 if (s->control & 1) {
126 mpcore_timer_reload(s, 1);
128 break;
129 case 8: /* Control. */
130 old = s->control;
131 s->control = value;
132 if (((old & 1) == 0) && (value & 1)) {
133 if (s->count == 0 && (s->control & 2))
134 s->count = s->load;
135 mpcore_timer_reload(s, 1);
137 break;
138 case 12: /* Interrupt status. */
139 s->status &= ~value;
140 mpcore_timer_update_irq(s);
141 break;
145 static void mpcore_timer_init(mpcore_priv_state *mpcore,
146 mpcore_timer_state *s, int id)
148 s->id = id;
149 s->mpcore = mpcore;
150 s->timer = qemu_new_timer(vm_clock, mpcore_timer_tick, s);
154 /* Per-CPU private memory mapped IO. */
156 static uint32_t mpcore_priv_read(void *opaque, target_phys_addr_t offset)
158 mpcore_priv_state *s = (mpcore_priv_state *)opaque;
159 int id;
160 offset &= 0xfff;
161 if (offset < 0x100) {
162 /* SCU */
163 switch (offset) {
164 case 0x00: /* Control. */
165 return s->scu_control;
166 case 0x04: /* Configuration. */
167 return 0xf3;
168 case 0x08: /* CPU status. */
169 return 0;
170 case 0x0c: /* Invalidate all. */
171 return 0;
172 default:
173 goto bad_reg;
175 } else if (offset < 0x600) {
176 /* Interrupt controller. */
177 if (offset < 0x200) {
178 id = gic_get_current_cpu();
179 } else {
180 id = (offset - 0x200) >> 8;
182 return gic_cpu_read(s->gic, id, offset & 0xff);
183 } else if (offset < 0xb00) {
184 /* Timers. */
185 if (offset < 0x700) {
186 id = gic_get_current_cpu();
187 } else {
188 id = (offset - 0x700) >> 8;
190 id <<= 1;
191 if (offset & 0x20)
192 id++;
193 return mpcore_timer_read(&s->timer[id], offset & 0xf);
195 bad_reg:
196 cpu_abort(cpu_single_env, "mpcore_priv_read: Bad offset %x\n",
197 (int)offset);
198 return 0;
201 static void mpcore_priv_write(void *opaque, target_phys_addr_t offset,
202 uint32_t value)
204 mpcore_priv_state *s = (mpcore_priv_state *)opaque;
205 int id;
206 offset &= 0xfff;
207 if (offset < 0x100) {
208 /* SCU */
209 switch (offset) {
210 case 0: /* Control register. */
211 s->scu_control = value & 1;
212 break;
213 case 0x0c: /* Invalidate all. */
214 /* This is a no-op as cache is not emulated. */
215 break;
216 default:
217 goto bad_reg;
219 } else if (offset < 0x600) {
220 /* Interrupt controller. */
221 if (offset < 0x200) {
222 id = gic_get_current_cpu();
223 } else {
224 id = (offset - 0x200) >> 8;
226 gic_cpu_write(s->gic, id, offset & 0xff, value);
227 } else if (offset < 0xb00) {
228 /* Timers. */
229 if (offset < 0x700) {
230 id = gic_get_current_cpu();
231 } else {
232 id = (offset - 0x700) >> 8;
234 id <<= 1;
235 if (offset & 0x20)
236 id++;
237 mpcore_timer_write(&s->timer[id], offset & 0xf, value);
238 return;
240 return;
241 bad_reg:
242 cpu_abort(cpu_single_env, "mpcore_priv_read: Bad offset %x\n",
243 (int)offset);
246 static CPUReadMemoryFunc *mpcore_priv_readfn[] = {
247 mpcore_priv_read,
248 mpcore_priv_read,
249 mpcore_priv_read
252 static CPUWriteMemoryFunc *mpcore_priv_writefn[] = {
253 mpcore_priv_write,
254 mpcore_priv_write,
255 mpcore_priv_write
259 static qemu_irq *mpcore_priv_init(uint32_t base, qemu_irq *pic_irq)
261 mpcore_priv_state *s;
262 int iomemtype;
263 int i;
265 s = (mpcore_priv_state *)qemu_mallocz(sizeof(mpcore_priv_state));
266 if (!s)
267 return NULL;
268 s->gic = gic_init(base, pic_irq);
269 if (!s->gic)
270 return NULL;
271 iomemtype = cpu_register_io_memory(0, mpcore_priv_readfn,
272 mpcore_priv_writefn, s);
273 cpu_register_physical_memory(base, 0x00001000, iomemtype);
274 for (i = 0; i < 8; i++) {
275 mpcore_timer_init(s, &s->timer[i], i);
277 return s->gic->in;
280 /* Dummy PIC to route IRQ lines. The baseboard has 4 independent IRQ
281 controllers. The output of these, plus some of the raw input lines
282 are fed into a single SMP-aware interrupt controller on the CPU. */
283 typedef struct {
284 qemu_irq *cpuic;
285 qemu_irq *rvic[4];
286 } mpcore_rirq_state;
288 /* Map baseboard IRQs onto CPU IRQ lines. */
289 static const int mpcore_irq_map[32] = {
290 -1, -1, -1, -1, 1, 2, -1, -1,
291 -1, -1, 6, -1, 4, 5, -1, -1,
292 -1, 14, 15, 0, 7, 8, -1, -1,
293 -1, -1, -1, -1, 9, 3, -1, -1,
296 static void mpcore_rirq_set_irq(void *opaque, int irq, int level)
298 mpcore_rirq_state *s = (mpcore_rirq_state *)opaque;
299 int i;
301 for (i = 0; i < 4; i++) {
302 qemu_set_irq(s->rvic[i][irq], level);
304 if (irq < 32) {
305 irq = mpcore_irq_map[irq];
306 if (irq >= 0) {
307 qemu_set_irq(s->cpuic[irq], level);
312 qemu_irq *mpcore_irq_init(qemu_irq *cpu_irq)
314 mpcore_rirq_state *s;
315 int n;
317 /* ??? IRQ routing is hardcoded to "normal" mode. */
318 s = qemu_mallocz(sizeof(mpcore_rirq_state));
319 s->cpuic = mpcore_priv_init(MPCORE_PRIV_BASE, cpu_irq);
320 for (n = 0; n < 4; n++) {
321 s->rvic[n] = realview_gic_init(0x10040000 + n * 0x10000,
322 s->cpuic[10 + n]);
324 return qemu_allocate_irqs(mpcore_rirq_set_irq, s, 64);