xref: /openbmc/qemu/hw/ppc/ppc.c (revision 2993683b)
1 /*
2  * QEMU generic PowerPC hardware System Emulator
3  *
4  * Copyright (c) 2003-2007 Jocelyn Mayer
5  *
6  * Permission is hereby granted, free of charge, to any person obtaining a copy
7  * of this software and associated documentation files (the "Software"), to deal
8  * in the Software without restriction, including without limitation the rights
9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
10  * copies of the Software, and to permit persons to whom the Software is
11  * furnished to do so, subject to the following conditions:
12  *
13  * The above copyright notice and this permission notice shall be included in
14  * all copies or substantial portions of the Software.
15  *
16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
22  * THE SOFTWARE.
23  */
24 #include "hw/hw.h"
25 #include "hw/ppc/ppc.h"
26 #include "qemu/timer.h"
27 #include "sysemu/sysemu.h"
28 #include "hw/timer/m48t59.h"
29 #include "qemu/log.h"
30 #include "hw/loader.h"
31 #include "sysemu/kvm.h"
32 #include "kvm_ppc.h"
33 
34 //#define PPC_DEBUG_IRQ
35 //#define PPC_DEBUG_TB
36 
37 #ifdef PPC_DEBUG_IRQ
38 #  define LOG_IRQ(...) qemu_log_mask(CPU_LOG_INT, ## __VA_ARGS__)
39 #else
40 #  define LOG_IRQ(...) do { } while (0)
41 #endif
42 
43 
44 #ifdef PPC_DEBUG_TB
45 #  define LOG_TB(...) qemu_log(__VA_ARGS__)
46 #else
47 #  define LOG_TB(...) do { } while (0)
48 #endif
49 
50 static void cpu_ppc_tb_stop (CPUPPCState *env);
51 static void cpu_ppc_tb_start (CPUPPCState *env);
52 
53 void ppc_set_irq(PowerPCCPU *cpu, int n_IRQ, int level)
54 {
55     CPUState *cs = CPU(cpu);
56     CPUPPCState *env = &cpu->env;
57     unsigned int old_pending = env->pending_interrupts;
58 
59     if (level) {
60         env->pending_interrupts |= 1 << n_IRQ;
61         cpu_interrupt(cs, CPU_INTERRUPT_HARD);
62     } else {
63         env->pending_interrupts &= ~(1 << n_IRQ);
64         if (env->pending_interrupts == 0) {
65             cpu_reset_interrupt(cs, CPU_INTERRUPT_HARD);
66         }
67     }
68 
69     if (old_pending != env->pending_interrupts) {
70 #ifdef CONFIG_KVM
71         kvmppc_set_interrupt(cpu, n_IRQ, level);
72 #endif
73     }
74 
75     LOG_IRQ("%s: %p n_IRQ %d level %d => pending %08" PRIx32
76                 "req %08x\n", __func__, env, n_IRQ, level,
77                 env->pending_interrupts, CPU(cpu)->interrupt_request);
78 }
79 
80 /* PowerPC 6xx / 7xx internal IRQ controller */
81 static void ppc6xx_set_irq(void *opaque, int pin, int level)
82 {
83     PowerPCCPU *cpu = opaque;
84     CPUPPCState *env = &cpu->env;
85     int cur_level;
86 
87     LOG_IRQ("%s: env %p pin %d level %d\n", __func__,
88                 env, pin, level);
89     cur_level = (env->irq_input_state >> pin) & 1;
90     /* Don't generate spurious events */
91     if ((cur_level == 1 && level == 0) || (cur_level == 0 && level != 0)) {
92         CPUState *cs = CPU(cpu);
93 
94         switch (pin) {
95         case PPC6xx_INPUT_TBEN:
96             /* Level sensitive - active high */
97             LOG_IRQ("%s: %s the time base\n",
98                         __func__, level ? "start" : "stop");
99             if (level) {
100                 cpu_ppc_tb_start(env);
101             } else {
102                 cpu_ppc_tb_stop(env);
103             }
104         case PPC6xx_INPUT_INT:
105             /* Level sensitive - active high */
106             LOG_IRQ("%s: set the external IRQ state to %d\n",
107                         __func__, level);
108             ppc_set_irq(cpu, PPC_INTERRUPT_EXT, level);
109             break;
110         case PPC6xx_INPUT_SMI:
111             /* Level sensitive - active high */
112             LOG_IRQ("%s: set the SMI IRQ state to %d\n",
113                         __func__, level);
114             ppc_set_irq(cpu, PPC_INTERRUPT_SMI, level);
115             break;
116         case PPC6xx_INPUT_MCP:
117             /* Negative edge sensitive */
118             /* XXX: TODO: actual reaction may depends on HID0 status
119              *            603/604/740/750: check HID0[EMCP]
120              */
121             if (cur_level == 1 && level == 0) {
122                 LOG_IRQ("%s: raise machine check state\n",
123                             __func__);
124                 ppc_set_irq(cpu, PPC_INTERRUPT_MCK, 1);
125             }
126             break;
127         case PPC6xx_INPUT_CKSTP_IN:
128             /* Level sensitive - active low */
129             /* XXX: TODO: relay the signal to CKSTP_OUT pin */
130             /* XXX: Note that the only way to restart the CPU is to reset it */
131             if (level) {
132                 LOG_IRQ("%s: stop the CPU\n", __func__);
133                 cs->halted = 1;
134             }
135             break;
136         case PPC6xx_INPUT_HRESET:
137             /* Level sensitive - active low */
138             if (level) {
139                 LOG_IRQ("%s: reset the CPU\n", __func__);
140                 cpu_interrupt(cs, CPU_INTERRUPT_RESET);
141             }
142             break;
143         case PPC6xx_INPUT_SRESET:
144             LOG_IRQ("%s: set the RESET IRQ state to %d\n",
145                         __func__, level);
146             ppc_set_irq(cpu, PPC_INTERRUPT_RESET, level);
147             break;
148         default:
149             /* Unknown pin - do nothing */
150             LOG_IRQ("%s: unknown IRQ pin %d\n", __func__, pin);
151             return;
152         }
153         if (level)
154             env->irq_input_state |= 1 << pin;
155         else
156             env->irq_input_state &= ~(1 << pin);
157     }
158 }
159 
160 void ppc6xx_irq_init(CPUPPCState *env)
161 {
162     PowerPCCPU *cpu = ppc_env_get_cpu(env);
163 
164     env->irq_inputs = (void **)qemu_allocate_irqs(&ppc6xx_set_irq, cpu,
165                                                   PPC6xx_INPUT_NB);
166 }
167 
168 #if defined(TARGET_PPC64)
169 /* PowerPC 970 internal IRQ controller */
170 static void ppc970_set_irq(void *opaque, int pin, int level)
171 {
172     PowerPCCPU *cpu = opaque;
173     CPUPPCState *env = &cpu->env;
174     int cur_level;
175 
176     LOG_IRQ("%s: env %p pin %d level %d\n", __func__,
177                 env, pin, level);
178     cur_level = (env->irq_input_state >> pin) & 1;
179     /* Don't generate spurious events */
180     if ((cur_level == 1 && level == 0) || (cur_level == 0 && level != 0)) {
181         CPUState *cs = CPU(cpu);
182 
183         switch (pin) {
184         case PPC970_INPUT_INT:
185             /* Level sensitive - active high */
186             LOG_IRQ("%s: set the external IRQ state to %d\n",
187                         __func__, level);
188             ppc_set_irq(cpu, PPC_INTERRUPT_EXT, level);
189             break;
190         case PPC970_INPUT_THINT:
191             /* Level sensitive - active high */
192             LOG_IRQ("%s: set the SMI IRQ state to %d\n", __func__,
193                         level);
194             ppc_set_irq(cpu, PPC_INTERRUPT_THERM, level);
195             break;
196         case PPC970_INPUT_MCP:
197             /* Negative edge sensitive */
198             /* XXX: TODO: actual reaction may depends on HID0 status
199              *            603/604/740/750: check HID0[EMCP]
200              */
201             if (cur_level == 1 && level == 0) {
202                 LOG_IRQ("%s: raise machine check state\n",
203                             __func__);
204                 ppc_set_irq(cpu, PPC_INTERRUPT_MCK, 1);
205             }
206             break;
207         case PPC970_INPUT_CKSTP:
208             /* Level sensitive - active low */
209             /* XXX: TODO: relay the signal to CKSTP_OUT pin */
210             if (level) {
211                 LOG_IRQ("%s: stop the CPU\n", __func__);
212                 cs->halted = 1;
213             } else {
214                 LOG_IRQ("%s: restart the CPU\n", __func__);
215                 cs->halted = 0;
216                 qemu_cpu_kick(cs);
217             }
218             break;
219         case PPC970_INPUT_HRESET:
220             /* Level sensitive - active low */
221             if (level) {
222                 cpu_interrupt(cs, CPU_INTERRUPT_RESET);
223             }
224             break;
225         case PPC970_INPUT_SRESET:
226             LOG_IRQ("%s: set the RESET IRQ state to %d\n",
227                         __func__, level);
228             ppc_set_irq(cpu, PPC_INTERRUPT_RESET, level);
229             break;
230         case PPC970_INPUT_TBEN:
231             LOG_IRQ("%s: set the TBEN state to %d\n", __func__,
232                         level);
233             /* XXX: TODO */
234             break;
235         default:
236             /* Unknown pin - do nothing */
237             LOG_IRQ("%s: unknown IRQ pin %d\n", __func__, pin);
238             return;
239         }
240         if (level)
241             env->irq_input_state |= 1 << pin;
242         else
243             env->irq_input_state &= ~(1 << pin);
244     }
245 }
246 
247 void ppc970_irq_init(CPUPPCState *env)
248 {
249     PowerPCCPU *cpu = ppc_env_get_cpu(env);
250 
251     env->irq_inputs = (void **)qemu_allocate_irqs(&ppc970_set_irq, cpu,
252                                                   PPC970_INPUT_NB);
253 }
254 
255 /* POWER7 internal IRQ controller */
256 static void power7_set_irq(void *opaque, int pin, int level)
257 {
258     PowerPCCPU *cpu = opaque;
259     CPUPPCState *env = &cpu->env;
260 
261     LOG_IRQ("%s: env %p pin %d level %d\n", __func__,
262                 env, pin, level);
263 
264     switch (pin) {
265     case POWER7_INPUT_INT:
266         /* Level sensitive - active high */
267         LOG_IRQ("%s: set the external IRQ state to %d\n",
268                 __func__, level);
269         ppc_set_irq(cpu, PPC_INTERRUPT_EXT, level);
270         break;
271     default:
272         /* Unknown pin - do nothing */
273         LOG_IRQ("%s: unknown IRQ pin %d\n", __func__, pin);
274         return;
275     }
276     if (level) {
277         env->irq_input_state |= 1 << pin;
278     } else {
279         env->irq_input_state &= ~(1 << pin);
280     }
281 }
282 
283 void ppcPOWER7_irq_init(CPUPPCState *env)
284 {
285     PowerPCCPU *cpu = ppc_env_get_cpu(env);
286 
287     env->irq_inputs = (void **)qemu_allocate_irqs(&power7_set_irq, cpu,
288                                                   POWER7_INPUT_NB);
289 }
290 #endif /* defined(TARGET_PPC64) */
291 
292 /* PowerPC 40x internal IRQ controller */
293 static void ppc40x_set_irq(void *opaque, int pin, int level)
294 {
295     PowerPCCPU *cpu = opaque;
296     CPUPPCState *env = &cpu->env;
297     int cur_level;
298 
299     LOG_IRQ("%s: env %p pin %d level %d\n", __func__,
300                 env, pin, level);
301     cur_level = (env->irq_input_state >> pin) & 1;
302     /* Don't generate spurious events */
303     if ((cur_level == 1 && level == 0) || (cur_level == 0 && level != 0)) {
304         CPUState *cs = CPU(cpu);
305 
306         switch (pin) {
307         case PPC40x_INPUT_RESET_SYS:
308             if (level) {
309                 LOG_IRQ("%s: reset the PowerPC system\n",
310                             __func__);
311                 ppc40x_system_reset(cpu);
312             }
313             break;
314         case PPC40x_INPUT_RESET_CHIP:
315             if (level) {
316                 LOG_IRQ("%s: reset the PowerPC chip\n", __func__);
317                 ppc40x_chip_reset(cpu);
318             }
319             break;
320         case PPC40x_INPUT_RESET_CORE:
321             /* XXX: TODO: update DBSR[MRR] */
322             if (level) {
323                 LOG_IRQ("%s: reset the PowerPC core\n", __func__);
324                 ppc40x_core_reset(cpu);
325             }
326             break;
327         case PPC40x_INPUT_CINT:
328             /* Level sensitive - active high */
329             LOG_IRQ("%s: set the critical IRQ state to %d\n",
330                         __func__, level);
331             ppc_set_irq(cpu, PPC_INTERRUPT_CEXT, level);
332             break;
333         case PPC40x_INPUT_INT:
334             /* Level sensitive - active high */
335             LOG_IRQ("%s: set the external IRQ state to %d\n",
336                         __func__, level);
337             ppc_set_irq(cpu, PPC_INTERRUPT_EXT, level);
338             break;
339         case PPC40x_INPUT_HALT:
340             /* Level sensitive - active low */
341             if (level) {
342                 LOG_IRQ("%s: stop the CPU\n", __func__);
343                 cs->halted = 1;
344             } else {
345                 LOG_IRQ("%s: restart the CPU\n", __func__);
346                 cs->halted = 0;
347                 qemu_cpu_kick(cs);
348             }
349             break;
350         case PPC40x_INPUT_DEBUG:
351             /* Level sensitive - active high */
352             LOG_IRQ("%s: set the debug pin state to %d\n",
353                         __func__, level);
354             ppc_set_irq(cpu, PPC_INTERRUPT_DEBUG, level);
355             break;
356         default:
357             /* Unknown pin - do nothing */
358             LOG_IRQ("%s: unknown IRQ pin %d\n", __func__, pin);
359             return;
360         }
361         if (level)
362             env->irq_input_state |= 1 << pin;
363         else
364             env->irq_input_state &= ~(1 << pin);
365     }
366 }
367 
368 void ppc40x_irq_init(CPUPPCState *env)
369 {
370     PowerPCCPU *cpu = ppc_env_get_cpu(env);
371 
372     env->irq_inputs = (void **)qemu_allocate_irqs(&ppc40x_set_irq,
373                                                   cpu, PPC40x_INPUT_NB);
374 }
375 
376 /* PowerPC E500 internal IRQ controller */
377 static void ppce500_set_irq(void *opaque, int pin, int level)
378 {
379     PowerPCCPU *cpu = opaque;
380     CPUPPCState *env = &cpu->env;
381     int cur_level;
382 
383     LOG_IRQ("%s: env %p pin %d level %d\n", __func__,
384                 env, pin, level);
385     cur_level = (env->irq_input_state >> pin) & 1;
386     /* Don't generate spurious events */
387     if ((cur_level == 1 && level == 0) || (cur_level == 0 && level != 0)) {
388         switch (pin) {
389         case PPCE500_INPUT_MCK:
390             if (level) {
391                 LOG_IRQ("%s: reset the PowerPC system\n",
392                             __func__);
393                 qemu_system_reset_request();
394             }
395             break;
396         case PPCE500_INPUT_RESET_CORE:
397             if (level) {
398                 LOG_IRQ("%s: reset the PowerPC core\n", __func__);
399                 ppc_set_irq(cpu, PPC_INTERRUPT_MCK, level);
400             }
401             break;
402         case PPCE500_INPUT_CINT:
403             /* Level sensitive - active high */
404             LOG_IRQ("%s: set the critical IRQ state to %d\n",
405                         __func__, level);
406             ppc_set_irq(cpu, PPC_INTERRUPT_CEXT, level);
407             break;
408         case PPCE500_INPUT_INT:
409             /* Level sensitive - active high */
410             LOG_IRQ("%s: set the core IRQ state to %d\n",
411                         __func__, level);
412             ppc_set_irq(cpu, PPC_INTERRUPT_EXT, level);
413             break;
414         case PPCE500_INPUT_DEBUG:
415             /* Level sensitive - active high */
416             LOG_IRQ("%s: set the debug pin state to %d\n",
417                         __func__, level);
418             ppc_set_irq(cpu, PPC_INTERRUPT_DEBUG, level);
419             break;
420         default:
421             /* Unknown pin - do nothing */
422             LOG_IRQ("%s: unknown IRQ pin %d\n", __func__, pin);
423             return;
424         }
425         if (level)
426             env->irq_input_state |= 1 << pin;
427         else
428             env->irq_input_state &= ~(1 << pin);
429     }
430 }
431 
432 void ppce500_irq_init(CPUPPCState *env)
433 {
434     PowerPCCPU *cpu = ppc_env_get_cpu(env);
435 
436     env->irq_inputs = (void **)qemu_allocate_irqs(&ppce500_set_irq,
437                                                   cpu, PPCE500_INPUT_NB);
438 }
439 
440 /* Enable or Disable the E500 EPR capability */
441 void ppce500_set_mpic_proxy(bool enabled)
442 {
443     CPUPPCState *env;
444 
445     for (env = first_cpu; env != NULL; env = env->next_cpu) {
446         PowerPCCPU *cpu = ppc_env_get_cpu(env);
447         CPUState *cs = CPU(cpu);
448 
449         env->mpic_proxy = enabled;
450         if (kvm_enabled()) {
451             kvmppc_set_mpic_proxy(POWERPC_CPU(cs), enabled);
452         }
453     }
454 }
455 
456 /*****************************************************************************/
457 /* PowerPC time base and decrementer emulation */
458 
459 uint64_t cpu_ppc_get_tb(ppc_tb_t *tb_env, uint64_t vmclk, int64_t tb_offset)
460 {
461     /* TB time in tb periods */
462     return muldiv64(vmclk, tb_env->tb_freq, get_ticks_per_sec()) + tb_offset;
463 }
464 
465 uint64_t cpu_ppc_load_tbl (CPUPPCState *env)
466 {
467     ppc_tb_t *tb_env = env->tb_env;
468     uint64_t tb;
469 
470     if (kvm_enabled()) {
471         return env->spr[SPR_TBL];
472     }
473 
474     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->tb_offset);
475     LOG_TB("%s: tb %016" PRIx64 "\n", __func__, tb);
476 
477     return tb;
478 }
479 
480 static inline uint32_t _cpu_ppc_load_tbu(CPUPPCState *env)
481 {
482     ppc_tb_t *tb_env = env->tb_env;
483     uint64_t tb;
484 
485     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->tb_offset);
486     LOG_TB("%s: tb %016" PRIx64 "\n", __func__, tb);
487 
488     return tb >> 32;
489 }
490 
491 uint32_t cpu_ppc_load_tbu (CPUPPCState *env)
492 {
493     if (kvm_enabled()) {
494         return env->spr[SPR_TBU];
495     }
496 
497     return _cpu_ppc_load_tbu(env);
498 }
499 
500 static inline void cpu_ppc_store_tb(ppc_tb_t *tb_env, uint64_t vmclk,
501                                     int64_t *tb_offsetp, uint64_t value)
502 {
503     *tb_offsetp = value - muldiv64(vmclk, tb_env->tb_freq, get_ticks_per_sec());
504     LOG_TB("%s: tb %016" PRIx64 " offset %08" PRIx64 "\n",
505                 __func__, value, *tb_offsetp);
506 }
507 
508 void cpu_ppc_store_tbl (CPUPPCState *env, uint32_t value)
509 {
510     ppc_tb_t *tb_env = env->tb_env;
511     uint64_t tb;
512 
513     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->tb_offset);
514     tb &= 0xFFFFFFFF00000000ULL;
515     cpu_ppc_store_tb(tb_env, qemu_get_clock_ns(vm_clock),
516                      &tb_env->tb_offset, tb | (uint64_t)value);
517 }
518 
519 static inline void _cpu_ppc_store_tbu(CPUPPCState *env, uint32_t value)
520 {
521     ppc_tb_t *tb_env = env->tb_env;
522     uint64_t tb;
523 
524     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->tb_offset);
525     tb &= 0x00000000FFFFFFFFULL;
526     cpu_ppc_store_tb(tb_env, qemu_get_clock_ns(vm_clock),
527                      &tb_env->tb_offset, ((uint64_t)value << 32) | tb);
528 }
529 
530 void cpu_ppc_store_tbu (CPUPPCState *env, uint32_t value)
531 {
532     _cpu_ppc_store_tbu(env, value);
533 }
534 
535 uint64_t cpu_ppc_load_atbl (CPUPPCState *env)
536 {
537     ppc_tb_t *tb_env = env->tb_env;
538     uint64_t tb;
539 
540     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->atb_offset);
541     LOG_TB("%s: tb %016" PRIx64 "\n", __func__, tb);
542 
543     return tb;
544 }
545 
546 uint32_t cpu_ppc_load_atbu (CPUPPCState *env)
547 {
548     ppc_tb_t *tb_env = env->tb_env;
549     uint64_t tb;
550 
551     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->atb_offset);
552     LOG_TB("%s: tb %016" PRIx64 "\n", __func__, tb);
553 
554     return tb >> 32;
555 }
556 
557 void cpu_ppc_store_atbl (CPUPPCState *env, uint32_t value)
558 {
559     ppc_tb_t *tb_env = env->tb_env;
560     uint64_t tb;
561 
562     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->atb_offset);
563     tb &= 0xFFFFFFFF00000000ULL;
564     cpu_ppc_store_tb(tb_env, qemu_get_clock_ns(vm_clock),
565                      &tb_env->atb_offset, tb | (uint64_t)value);
566 }
567 
568 void cpu_ppc_store_atbu (CPUPPCState *env, uint32_t value)
569 {
570     ppc_tb_t *tb_env = env->tb_env;
571     uint64_t tb;
572 
573     tb = cpu_ppc_get_tb(tb_env, qemu_get_clock_ns(vm_clock), tb_env->atb_offset);
574     tb &= 0x00000000FFFFFFFFULL;
575     cpu_ppc_store_tb(tb_env, qemu_get_clock_ns(vm_clock),
576                      &tb_env->atb_offset, ((uint64_t)value << 32) | tb);
577 }
578 
579 static void cpu_ppc_tb_stop (CPUPPCState *env)
580 {
581     ppc_tb_t *tb_env = env->tb_env;
582     uint64_t tb, atb, vmclk;
583 
584     /* If the time base is already frozen, do nothing */
585     if (tb_env->tb_freq != 0) {
586         vmclk = qemu_get_clock_ns(vm_clock);
587         /* Get the time base */
588         tb = cpu_ppc_get_tb(tb_env, vmclk, tb_env->tb_offset);
589         /* Get the alternate time base */
590         atb = cpu_ppc_get_tb(tb_env, vmclk, tb_env->atb_offset);
591         /* Store the time base value (ie compute the current offset) */
592         cpu_ppc_store_tb(tb_env, vmclk, &tb_env->tb_offset, tb);
593         /* Store the alternate time base value (compute the current offset) */
594         cpu_ppc_store_tb(tb_env, vmclk, &tb_env->atb_offset, atb);
595         /* Set the time base frequency to zero */
596         tb_env->tb_freq = 0;
597         /* Now, the time bases are frozen to tb_offset / atb_offset value */
598     }
599 }
600 
601 static void cpu_ppc_tb_start (CPUPPCState *env)
602 {
603     ppc_tb_t *tb_env = env->tb_env;
604     uint64_t tb, atb, vmclk;
605 
606     /* If the time base is not frozen, do nothing */
607     if (tb_env->tb_freq == 0) {
608         vmclk = qemu_get_clock_ns(vm_clock);
609         /* Get the time base from tb_offset */
610         tb = tb_env->tb_offset;
611         /* Get the alternate time base from atb_offset */
612         atb = tb_env->atb_offset;
613         /* Restore the tb frequency from the decrementer frequency */
614         tb_env->tb_freq = tb_env->decr_freq;
615         /* Store the time base value */
616         cpu_ppc_store_tb(tb_env, vmclk, &tb_env->tb_offset, tb);
617         /* Store the alternate time base value */
618         cpu_ppc_store_tb(tb_env, vmclk, &tb_env->atb_offset, atb);
619     }
620 }
621 
622 static inline uint32_t _cpu_ppc_load_decr(CPUPPCState *env, uint64_t next)
623 {
624     ppc_tb_t *tb_env = env->tb_env;
625     uint32_t decr;
626     int64_t diff;
627 
628     diff = next - qemu_get_clock_ns(vm_clock);
629     if (diff >= 0) {
630         decr = muldiv64(diff, tb_env->decr_freq, get_ticks_per_sec());
631     } else if (tb_env->flags & PPC_TIMER_BOOKE) {
632         decr = 0;
633     }  else {
634         decr = -muldiv64(-diff, tb_env->decr_freq, get_ticks_per_sec());
635     }
636     LOG_TB("%s: %08" PRIx32 "\n", __func__, decr);
637 
638     return decr;
639 }
640 
641 uint32_t cpu_ppc_load_decr (CPUPPCState *env)
642 {
643     ppc_tb_t *tb_env = env->tb_env;
644 
645     if (kvm_enabled()) {
646         return env->spr[SPR_DECR];
647     }
648 
649     return _cpu_ppc_load_decr(env, tb_env->decr_next);
650 }
651 
652 uint32_t cpu_ppc_load_hdecr (CPUPPCState *env)
653 {
654     ppc_tb_t *tb_env = env->tb_env;
655 
656     return _cpu_ppc_load_decr(env, tb_env->hdecr_next);
657 }
658 
659 uint64_t cpu_ppc_load_purr (CPUPPCState *env)
660 {
661     ppc_tb_t *tb_env = env->tb_env;
662     uint64_t diff;
663 
664     diff = qemu_get_clock_ns(vm_clock) - tb_env->purr_start;
665 
666     return tb_env->purr_load + muldiv64(diff, tb_env->tb_freq, get_ticks_per_sec());
667 }
668 
669 /* When decrementer expires,
670  * all we need to do is generate or queue a CPU exception
671  */
672 static inline void cpu_ppc_decr_excp(PowerPCCPU *cpu)
673 {
674     /* Raise it */
675     LOG_TB("raise decrementer exception\n");
676     ppc_set_irq(cpu, PPC_INTERRUPT_DECR, 1);
677 }
678 
679 static inline void cpu_ppc_hdecr_excp(PowerPCCPU *cpu)
680 {
681     /* Raise it */
682     LOG_TB("raise decrementer exception\n");
683     ppc_set_irq(cpu, PPC_INTERRUPT_HDECR, 1);
684 }
685 
686 static void __cpu_ppc_store_decr(PowerPCCPU *cpu, uint64_t *nextp,
687                                  struct QEMUTimer *timer,
688                                  void (*raise_excp)(PowerPCCPU *),
689                                  uint32_t decr, uint32_t value,
690                                  int is_excp)
691 {
692     CPUPPCState *env = &cpu->env;
693     ppc_tb_t *tb_env = env->tb_env;
694     uint64_t now, next;
695 
696     LOG_TB("%s: %08" PRIx32 " => %08" PRIx32 "\n", __func__,
697                 decr, value);
698 
699     if (kvm_enabled()) {
700         /* KVM handles decrementer exceptions, we don't need our own timer */
701         return;
702     }
703 
704     now = qemu_get_clock_ns(vm_clock);
705     next = now + muldiv64(value, get_ticks_per_sec(), tb_env->decr_freq);
706     if (is_excp) {
707         next += *nextp - now;
708     }
709     if (next == now) {
710         next++;
711     }
712     *nextp = next;
713     /* Adjust timer */
714     qemu_mod_timer(timer, next);
715 
716     /* If we set a negative value and the decrementer was positive, raise an
717      * exception.
718      */
719     if ((tb_env->flags & PPC_DECR_UNDERFLOW_TRIGGERED)
720         && (value & 0x80000000)
721         && !(decr & 0x80000000)) {
722         (*raise_excp)(cpu);
723     }
724 }
725 
726 static inline void _cpu_ppc_store_decr(PowerPCCPU *cpu, uint32_t decr,
727                                        uint32_t value, int is_excp)
728 {
729     ppc_tb_t *tb_env = cpu->env.tb_env;
730 
731     __cpu_ppc_store_decr(cpu, &tb_env->decr_next, tb_env->decr_timer,
732                          &cpu_ppc_decr_excp, decr, value, is_excp);
733 }
734 
735 void cpu_ppc_store_decr (CPUPPCState *env, uint32_t value)
736 {
737     PowerPCCPU *cpu = ppc_env_get_cpu(env);
738 
739     _cpu_ppc_store_decr(cpu, cpu_ppc_load_decr(env), value, 0);
740 }
741 
742 static void cpu_ppc_decr_cb(void *opaque)
743 {
744     PowerPCCPU *cpu = opaque;
745 
746     _cpu_ppc_store_decr(cpu, 0x00000000, 0xFFFFFFFF, 1);
747 }
748 
749 static inline void _cpu_ppc_store_hdecr(PowerPCCPU *cpu, uint32_t hdecr,
750                                         uint32_t value, int is_excp)
751 {
752     ppc_tb_t *tb_env = cpu->env.tb_env;
753 
754     if (tb_env->hdecr_timer != NULL) {
755         __cpu_ppc_store_decr(cpu, &tb_env->hdecr_next, tb_env->hdecr_timer,
756                              &cpu_ppc_hdecr_excp, hdecr, value, is_excp);
757     }
758 }
759 
760 void cpu_ppc_store_hdecr (CPUPPCState *env, uint32_t value)
761 {
762     PowerPCCPU *cpu = ppc_env_get_cpu(env);
763 
764     _cpu_ppc_store_hdecr(cpu, cpu_ppc_load_hdecr(env), value, 0);
765 }
766 
767 static void cpu_ppc_hdecr_cb(void *opaque)
768 {
769     PowerPCCPU *cpu = opaque;
770 
771     _cpu_ppc_store_hdecr(cpu, 0x00000000, 0xFFFFFFFF, 1);
772 }
773 
774 static void cpu_ppc_store_purr(PowerPCCPU *cpu, uint64_t value)
775 {
776     ppc_tb_t *tb_env = cpu->env.tb_env;
777 
778     tb_env->purr_load = value;
779     tb_env->purr_start = qemu_get_clock_ns(vm_clock);
780 }
781 
782 static void cpu_ppc_set_tb_clk (void *opaque, uint32_t freq)
783 {
784     CPUPPCState *env = opaque;
785     PowerPCCPU *cpu = ppc_env_get_cpu(env);
786     ppc_tb_t *tb_env = env->tb_env;
787 
788     tb_env->tb_freq = freq;
789     tb_env->decr_freq = freq;
790     /* There is a bug in Linux 2.4 kernels:
791      * if a decrementer exception is pending when it enables msr_ee at startup,
792      * it's not ready to handle it...
793      */
794     _cpu_ppc_store_decr(cpu, 0xFFFFFFFF, 0xFFFFFFFF, 0);
795     _cpu_ppc_store_hdecr(cpu, 0xFFFFFFFF, 0xFFFFFFFF, 0);
796     cpu_ppc_store_purr(cpu, 0x0000000000000000ULL);
797 }
798 
799 /* Set up (once) timebase frequency (in Hz) */
800 clk_setup_cb cpu_ppc_tb_init (CPUPPCState *env, uint32_t freq)
801 {
802     PowerPCCPU *cpu = ppc_env_get_cpu(env);
803     ppc_tb_t *tb_env;
804 
805     tb_env = g_malloc0(sizeof(ppc_tb_t));
806     env->tb_env = tb_env;
807     tb_env->flags = PPC_DECR_UNDERFLOW_TRIGGERED;
808     /* Create new timer */
809     tb_env->decr_timer = qemu_new_timer_ns(vm_clock, &cpu_ppc_decr_cb, cpu);
810     if (0) {
811         /* XXX: find a suitable condition to enable the hypervisor decrementer
812          */
813         tb_env->hdecr_timer = qemu_new_timer_ns(vm_clock, &cpu_ppc_hdecr_cb,
814                                                 cpu);
815     } else {
816         tb_env->hdecr_timer = NULL;
817     }
818     cpu_ppc_set_tb_clk(env, freq);
819 
820     return &cpu_ppc_set_tb_clk;
821 }
822 
823 /* Specific helpers for POWER & PowerPC 601 RTC */
824 #if 0
825 static clk_setup_cb cpu_ppc601_rtc_init (CPUPPCState *env)
826 {
827     return cpu_ppc_tb_init(env, 7812500);
828 }
829 #endif
830 
831 void cpu_ppc601_store_rtcu (CPUPPCState *env, uint32_t value)
832 {
833     _cpu_ppc_store_tbu(env, value);
834 }
835 
836 uint32_t cpu_ppc601_load_rtcu (CPUPPCState *env)
837 {
838     return _cpu_ppc_load_tbu(env);
839 }
840 
841 void cpu_ppc601_store_rtcl (CPUPPCState *env, uint32_t value)
842 {
843     cpu_ppc_store_tbl(env, value & 0x3FFFFF80);
844 }
845 
846 uint32_t cpu_ppc601_load_rtcl (CPUPPCState *env)
847 {
848     return cpu_ppc_load_tbl(env) & 0x3FFFFF80;
849 }
850 
851 /*****************************************************************************/
852 /* PowerPC 40x timers */
853 
854 /* PIT, FIT & WDT */
855 typedef struct ppc40x_timer_t ppc40x_timer_t;
856 struct ppc40x_timer_t {
857     uint64_t pit_reload;  /* PIT auto-reload value        */
858     uint64_t fit_next;    /* Tick for next FIT interrupt  */
859     struct QEMUTimer *fit_timer;
860     uint64_t wdt_next;    /* Tick for next WDT interrupt  */
861     struct QEMUTimer *wdt_timer;
862 
863     /* 405 have the PIT, 440 have a DECR.  */
864     unsigned int decr_excp;
865 };
866 
867 /* Fixed interval timer */
868 static void cpu_4xx_fit_cb (void *opaque)
869 {
870     PowerPCCPU *cpu;
871     CPUPPCState *env;
872     ppc_tb_t *tb_env;
873     ppc40x_timer_t *ppc40x_timer;
874     uint64_t now, next;
875 
876     env = opaque;
877     cpu = ppc_env_get_cpu(env);
878     tb_env = env->tb_env;
879     ppc40x_timer = tb_env->opaque;
880     now = qemu_get_clock_ns(vm_clock);
881     switch ((env->spr[SPR_40x_TCR] >> 24) & 0x3) {
882     case 0:
883         next = 1 << 9;
884         break;
885     case 1:
886         next = 1 << 13;
887         break;
888     case 2:
889         next = 1 << 17;
890         break;
891     case 3:
892         next = 1 << 21;
893         break;
894     default:
895         /* Cannot occur, but makes gcc happy */
896         return;
897     }
898     next = now + muldiv64(next, get_ticks_per_sec(), tb_env->tb_freq);
899     if (next == now)
900         next++;
901     qemu_mod_timer(ppc40x_timer->fit_timer, next);
902     env->spr[SPR_40x_TSR] |= 1 << 26;
903     if ((env->spr[SPR_40x_TCR] >> 23) & 0x1) {
904         ppc_set_irq(cpu, PPC_INTERRUPT_FIT, 1);
905     }
906     LOG_TB("%s: ir %d TCR " TARGET_FMT_lx " TSR " TARGET_FMT_lx "\n", __func__,
907            (int)((env->spr[SPR_40x_TCR] >> 23) & 0x1),
908            env->spr[SPR_40x_TCR], env->spr[SPR_40x_TSR]);
909 }
910 
911 /* Programmable interval timer */
912 static void start_stop_pit (CPUPPCState *env, ppc_tb_t *tb_env, int is_excp)
913 {
914     ppc40x_timer_t *ppc40x_timer;
915     uint64_t now, next;
916 
917     ppc40x_timer = tb_env->opaque;
918     if (ppc40x_timer->pit_reload <= 1 ||
919         !((env->spr[SPR_40x_TCR] >> 26) & 0x1) ||
920         (is_excp && !((env->spr[SPR_40x_TCR] >> 22) & 0x1))) {
921         /* Stop PIT */
922         LOG_TB("%s: stop PIT\n", __func__);
923         qemu_del_timer(tb_env->decr_timer);
924     } else {
925         LOG_TB("%s: start PIT %016" PRIx64 "\n",
926                     __func__, ppc40x_timer->pit_reload);
927         now = qemu_get_clock_ns(vm_clock);
928         next = now + muldiv64(ppc40x_timer->pit_reload,
929                               get_ticks_per_sec(), tb_env->decr_freq);
930         if (is_excp)
931             next += tb_env->decr_next - now;
932         if (next == now)
933             next++;
934         qemu_mod_timer(tb_env->decr_timer, next);
935         tb_env->decr_next = next;
936     }
937 }
938 
939 static void cpu_4xx_pit_cb (void *opaque)
940 {
941     PowerPCCPU *cpu;
942     CPUPPCState *env;
943     ppc_tb_t *tb_env;
944     ppc40x_timer_t *ppc40x_timer;
945 
946     env = opaque;
947     cpu = ppc_env_get_cpu(env);
948     tb_env = env->tb_env;
949     ppc40x_timer = tb_env->opaque;
950     env->spr[SPR_40x_TSR] |= 1 << 27;
951     if ((env->spr[SPR_40x_TCR] >> 26) & 0x1) {
952         ppc_set_irq(cpu, ppc40x_timer->decr_excp, 1);
953     }
954     start_stop_pit(env, tb_env, 1);
955     LOG_TB("%s: ar %d ir %d TCR " TARGET_FMT_lx " TSR " TARGET_FMT_lx " "
956            "%016" PRIx64 "\n", __func__,
957            (int)((env->spr[SPR_40x_TCR] >> 22) & 0x1),
958            (int)((env->spr[SPR_40x_TCR] >> 26) & 0x1),
959            env->spr[SPR_40x_TCR], env->spr[SPR_40x_TSR],
960            ppc40x_timer->pit_reload);
961 }
962 
963 /* Watchdog timer */
964 static void cpu_4xx_wdt_cb (void *opaque)
965 {
966     PowerPCCPU *cpu;
967     CPUPPCState *env;
968     ppc_tb_t *tb_env;
969     ppc40x_timer_t *ppc40x_timer;
970     uint64_t now, next;
971 
972     env = opaque;
973     cpu = ppc_env_get_cpu(env);
974     tb_env = env->tb_env;
975     ppc40x_timer = tb_env->opaque;
976     now = qemu_get_clock_ns(vm_clock);
977     switch ((env->spr[SPR_40x_TCR] >> 30) & 0x3) {
978     case 0:
979         next = 1 << 17;
980         break;
981     case 1:
982         next = 1 << 21;
983         break;
984     case 2:
985         next = 1 << 25;
986         break;
987     case 3:
988         next = 1 << 29;
989         break;
990     default:
991         /* Cannot occur, but makes gcc happy */
992         return;
993     }
994     next = now + muldiv64(next, get_ticks_per_sec(), tb_env->decr_freq);
995     if (next == now)
996         next++;
997     LOG_TB("%s: TCR " TARGET_FMT_lx " TSR " TARGET_FMT_lx "\n", __func__,
998            env->spr[SPR_40x_TCR], env->spr[SPR_40x_TSR]);
999     switch ((env->spr[SPR_40x_TSR] >> 30) & 0x3) {
1000     case 0x0:
1001     case 0x1:
1002         qemu_mod_timer(ppc40x_timer->wdt_timer, next);
1003         ppc40x_timer->wdt_next = next;
1004         env->spr[SPR_40x_TSR] |= 1 << 31;
1005         break;
1006     case 0x2:
1007         qemu_mod_timer(ppc40x_timer->wdt_timer, next);
1008         ppc40x_timer->wdt_next = next;
1009         env->spr[SPR_40x_TSR] |= 1 << 30;
1010         if ((env->spr[SPR_40x_TCR] >> 27) & 0x1) {
1011             ppc_set_irq(cpu, PPC_INTERRUPT_WDT, 1);
1012         }
1013         break;
1014     case 0x3:
1015         env->spr[SPR_40x_TSR] &= ~0x30000000;
1016         env->spr[SPR_40x_TSR] |= env->spr[SPR_40x_TCR] & 0x30000000;
1017         switch ((env->spr[SPR_40x_TCR] >> 28) & 0x3) {
1018         case 0x0:
1019             /* No reset */
1020             break;
1021         case 0x1: /* Core reset */
1022             ppc40x_core_reset(cpu);
1023             break;
1024         case 0x2: /* Chip reset */
1025             ppc40x_chip_reset(cpu);
1026             break;
1027         case 0x3: /* System reset */
1028             ppc40x_system_reset(cpu);
1029             break;
1030         }
1031     }
1032 }
1033 
1034 void store_40x_pit (CPUPPCState *env, target_ulong val)
1035 {
1036     ppc_tb_t *tb_env;
1037     ppc40x_timer_t *ppc40x_timer;
1038 
1039     tb_env = env->tb_env;
1040     ppc40x_timer = tb_env->opaque;
1041     LOG_TB("%s val" TARGET_FMT_lx "\n", __func__, val);
1042     ppc40x_timer->pit_reload = val;
1043     start_stop_pit(env, tb_env, 0);
1044 }
1045 
1046 target_ulong load_40x_pit (CPUPPCState *env)
1047 {
1048     return cpu_ppc_load_decr(env);
1049 }
1050 
1051 static void ppc_40x_set_tb_clk (void *opaque, uint32_t freq)
1052 {
1053     CPUPPCState *env = opaque;
1054     ppc_tb_t *tb_env = env->tb_env;
1055 
1056     LOG_TB("%s set new frequency to %" PRIu32 "\n", __func__,
1057                 freq);
1058     tb_env->tb_freq = freq;
1059     tb_env->decr_freq = freq;
1060     /* XXX: we should also update all timers */
1061 }
1062 
1063 clk_setup_cb ppc_40x_timers_init (CPUPPCState *env, uint32_t freq,
1064                                   unsigned int decr_excp)
1065 {
1066     ppc_tb_t *tb_env;
1067     ppc40x_timer_t *ppc40x_timer;
1068 
1069     tb_env = g_malloc0(sizeof(ppc_tb_t));
1070     env->tb_env = tb_env;
1071     tb_env->flags = PPC_DECR_UNDERFLOW_TRIGGERED;
1072     ppc40x_timer = g_malloc0(sizeof(ppc40x_timer_t));
1073     tb_env->tb_freq = freq;
1074     tb_env->decr_freq = freq;
1075     tb_env->opaque = ppc40x_timer;
1076     LOG_TB("%s freq %" PRIu32 "\n", __func__, freq);
1077     if (ppc40x_timer != NULL) {
1078         /* We use decr timer for PIT */
1079         tb_env->decr_timer = qemu_new_timer_ns(vm_clock, &cpu_4xx_pit_cb, env);
1080         ppc40x_timer->fit_timer =
1081             qemu_new_timer_ns(vm_clock, &cpu_4xx_fit_cb, env);
1082         ppc40x_timer->wdt_timer =
1083             qemu_new_timer_ns(vm_clock, &cpu_4xx_wdt_cb, env);
1084         ppc40x_timer->decr_excp = decr_excp;
1085     }
1086 
1087     return &ppc_40x_set_tb_clk;
1088 }
1089 
1090 /*****************************************************************************/
1091 /* Embedded PowerPC Device Control Registers */
1092 typedef struct ppc_dcrn_t ppc_dcrn_t;
1093 struct ppc_dcrn_t {
1094     dcr_read_cb dcr_read;
1095     dcr_write_cb dcr_write;
1096     void *opaque;
1097 };
1098 
1099 /* XXX: on 460, DCR addresses are 32 bits wide,
1100  *      using DCRIPR to get the 22 upper bits of the DCR address
1101  */
1102 #define DCRN_NB 1024
1103 struct ppc_dcr_t {
1104     ppc_dcrn_t dcrn[DCRN_NB];
1105     int (*read_error)(int dcrn);
1106     int (*write_error)(int dcrn);
1107 };
1108 
1109 int ppc_dcr_read (ppc_dcr_t *dcr_env, int dcrn, uint32_t *valp)
1110 {
1111     ppc_dcrn_t *dcr;
1112 
1113     if (dcrn < 0 || dcrn >= DCRN_NB)
1114         goto error;
1115     dcr = &dcr_env->dcrn[dcrn];
1116     if (dcr->dcr_read == NULL)
1117         goto error;
1118     *valp = (*dcr->dcr_read)(dcr->opaque, dcrn);
1119 
1120     return 0;
1121 
1122  error:
1123     if (dcr_env->read_error != NULL)
1124         return (*dcr_env->read_error)(dcrn);
1125 
1126     return -1;
1127 }
1128 
1129 int ppc_dcr_write (ppc_dcr_t *dcr_env, int dcrn, uint32_t val)
1130 {
1131     ppc_dcrn_t *dcr;
1132 
1133     if (dcrn < 0 || dcrn >= DCRN_NB)
1134         goto error;
1135     dcr = &dcr_env->dcrn[dcrn];
1136     if (dcr->dcr_write == NULL)
1137         goto error;
1138     (*dcr->dcr_write)(dcr->opaque, dcrn, val);
1139 
1140     return 0;
1141 
1142  error:
1143     if (dcr_env->write_error != NULL)
1144         return (*dcr_env->write_error)(dcrn);
1145 
1146     return -1;
1147 }
1148 
1149 int ppc_dcr_register (CPUPPCState *env, int dcrn, void *opaque,
1150                       dcr_read_cb dcr_read, dcr_write_cb dcr_write)
1151 {
1152     ppc_dcr_t *dcr_env;
1153     ppc_dcrn_t *dcr;
1154 
1155     dcr_env = env->dcr_env;
1156     if (dcr_env == NULL)
1157         return -1;
1158     if (dcrn < 0 || dcrn >= DCRN_NB)
1159         return -1;
1160     dcr = &dcr_env->dcrn[dcrn];
1161     if (dcr->opaque != NULL ||
1162         dcr->dcr_read != NULL ||
1163         dcr->dcr_write != NULL)
1164         return -1;
1165     dcr->opaque = opaque;
1166     dcr->dcr_read = dcr_read;
1167     dcr->dcr_write = dcr_write;
1168 
1169     return 0;
1170 }
1171 
1172 int ppc_dcr_init (CPUPPCState *env, int (*read_error)(int dcrn),
1173                   int (*write_error)(int dcrn))
1174 {
1175     ppc_dcr_t *dcr_env;
1176 
1177     dcr_env = g_malloc0(sizeof(ppc_dcr_t));
1178     dcr_env->read_error = read_error;
1179     dcr_env->write_error = write_error;
1180     env->dcr_env = dcr_env;
1181 
1182     return 0;
1183 }
1184 
1185 /*****************************************************************************/
1186 /* Debug port */
1187 void PPC_debug_write (void *opaque, uint32_t addr, uint32_t val)
1188 {
1189     addr &= 0xF;
1190     switch (addr) {
1191     case 0:
1192         printf("%c", val);
1193         break;
1194     case 1:
1195         printf("\n");
1196         fflush(stdout);
1197         break;
1198     case 2:
1199         printf("Set loglevel to %04" PRIx32 "\n", val);
1200         qemu_set_log(val | 0x100);
1201         break;
1202     }
1203 }
1204 
1205 /*****************************************************************************/
1206 /* NVRAM helpers */
1207 static inline uint32_t nvram_read (nvram_t *nvram, uint32_t addr)
1208 {
1209     return (*nvram->read_fn)(nvram->opaque, addr);
1210 }
1211 
1212 static inline void nvram_write (nvram_t *nvram, uint32_t addr, uint32_t val)
1213 {
1214     (*nvram->write_fn)(nvram->opaque, addr, val);
1215 }
1216 
1217 static void NVRAM_set_byte(nvram_t *nvram, uint32_t addr, uint8_t value)
1218 {
1219     nvram_write(nvram, addr, value);
1220 }
1221 
1222 static uint8_t NVRAM_get_byte(nvram_t *nvram, uint32_t addr)
1223 {
1224     return nvram_read(nvram, addr);
1225 }
1226 
1227 static void NVRAM_set_word(nvram_t *nvram, uint32_t addr, uint16_t value)
1228 {
1229     nvram_write(nvram, addr, value >> 8);
1230     nvram_write(nvram, addr + 1, value & 0xFF);
1231 }
1232 
1233 static uint16_t NVRAM_get_word(nvram_t *nvram, uint32_t addr)
1234 {
1235     uint16_t tmp;
1236 
1237     tmp = nvram_read(nvram, addr) << 8;
1238     tmp |= nvram_read(nvram, addr + 1);
1239 
1240     return tmp;
1241 }
1242 
1243 static void NVRAM_set_lword(nvram_t *nvram, uint32_t addr, uint32_t value)
1244 {
1245     nvram_write(nvram, addr, value >> 24);
1246     nvram_write(nvram, addr + 1, (value >> 16) & 0xFF);
1247     nvram_write(nvram, addr + 2, (value >> 8) & 0xFF);
1248     nvram_write(nvram, addr + 3, value & 0xFF);
1249 }
1250 
1251 uint32_t NVRAM_get_lword (nvram_t *nvram, uint32_t addr)
1252 {
1253     uint32_t tmp;
1254 
1255     tmp = nvram_read(nvram, addr) << 24;
1256     tmp |= nvram_read(nvram, addr + 1) << 16;
1257     tmp |= nvram_read(nvram, addr + 2) << 8;
1258     tmp |= nvram_read(nvram, addr + 3);
1259 
1260     return tmp;
1261 }
1262 
1263 static void NVRAM_set_string(nvram_t *nvram, uint32_t addr, const char *str,
1264                              uint32_t max)
1265 {
1266     int i;
1267 
1268     for (i = 0; i < max && str[i] != '\0'; i++) {
1269         nvram_write(nvram, addr + i, str[i]);
1270     }
1271     nvram_write(nvram, addr + i, str[i]);
1272     nvram_write(nvram, addr + max - 1, '\0');
1273 }
1274 
1275 int NVRAM_get_string (nvram_t *nvram, uint8_t *dst, uint16_t addr, int max)
1276 {
1277     int i;
1278 
1279     memset(dst, 0, max);
1280     for (i = 0; i < max; i++) {
1281         dst[i] = NVRAM_get_byte(nvram, addr + i);
1282         if (dst[i] == '\0')
1283             break;
1284     }
1285 
1286     return i;
1287 }
1288 
1289 static uint16_t NVRAM_crc_update (uint16_t prev, uint16_t value)
1290 {
1291     uint16_t tmp;
1292     uint16_t pd, pd1, pd2;
1293 
1294     tmp = prev >> 8;
1295     pd = prev ^ value;
1296     pd1 = pd & 0x000F;
1297     pd2 = ((pd >> 4) & 0x000F) ^ pd1;
1298     tmp ^= (pd1 << 3) | (pd1 << 8);
1299     tmp ^= pd2 | (pd2 << 7) | (pd2 << 12);
1300 
1301     return tmp;
1302 }
1303 
1304 static uint16_t NVRAM_compute_crc (nvram_t *nvram, uint32_t start, uint32_t count)
1305 {
1306     uint32_t i;
1307     uint16_t crc = 0xFFFF;
1308     int odd;
1309 
1310     odd = count & 1;
1311     count &= ~1;
1312     for (i = 0; i != count; i++) {
1313         crc = NVRAM_crc_update(crc, NVRAM_get_word(nvram, start + i));
1314     }
1315     if (odd) {
1316         crc = NVRAM_crc_update(crc, NVRAM_get_byte(nvram, start + i) << 8);
1317     }
1318 
1319     return crc;
1320 }
1321 
1322 #define CMDLINE_ADDR 0x017ff000
1323 
1324 int PPC_NVRAM_set_params (nvram_t *nvram, uint16_t NVRAM_size,
1325                           const char *arch,
1326                           uint32_t RAM_size, int boot_device,
1327                           uint32_t kernel_image, uint32_t kernel_size,
1328                           const char *cmdline,
1329                           uint32_t initrd_image, uint32_t initrd_size,
1330                           uint32_t NVRAM_image,
1331                           int width, int height, int depth)
1332 {
1333     uint16_t crc;
1334 
1335     /* Set parameters for Open Hack'Ware BIOS */
1336     NVRAM_set_string(nvram, 0x00, "QEMU_BIOS", 16);
1337     NVRAM_set_lword(nvram,  0x10, 0x00000002); /* structure v2 */
1338     NVRAM_set_word(nvram,   0x14, NVRAM_size);
1339     NVRAM_set_string(nvram, 0x20, arch, 16);
1340     NVRAM_set_lword(nvram,  0x30, RAM_size);
1341     NVRAM_set_byte(nvram,   0x34, boot_device);
1342     NVRAM_set_lword(nvram,  0x38, kernel_image);
1343     NVRAM_set_lword(nvram,  0x3C, kernel_size);
1344     if (cmdline) {
1345         /* XXX: put the cmdline in NVRAM too ? */
1346         pstrcpy_targphys("cmdline", CMDLINE_ADDR, RAM_size - CMDLINE_ADDR, cmdline);
1347         NVRAM_set_lword(nvram,  0x40, CMDLINE_ADDR);
1348         NVRAM_set_lword(nvram,  0x44, strlen(cmdline));
1349     } else {
1350         NVRAM_set_lword(nvram,  0x40, 0);
1351         NVRAM_set_lword(nvram,  0x44, 0);
1352     }
1353     NVRAM_set_lword(nvram,  0x48, initrd_image);
1354     NVRAM_set_lword(nvram,  0x4C, initrd_size);
1355     NVRAM_set_lword(nvram,  0x50, NVRAM_image);
1356 
1357     NVRAM_set_word(nvram,   0x54, width);
1358     NVRAM_set_word(nvram,   0x56, height);
1359     NVRAM_set_word(nvram,   0x58, depth);
1360     crc = NVRAM_compute_crc(nvram, 0x00, 0xF8);
1361     NVRAM_set_word(nvram,   0xFC, crc);
1362 
1363     return 0;
1364 }
1365