xref: /openbmc/qemu/hw/ppc/ppc4xx_devs.c (revision fcf5ef2a)
1 /*
2  * QEMU PowerPC 4xx embedded processors shared devices emulation
3  *
4  * Copyright (c) 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 "qemu/osdep.h"
25 #include "cpu.h"
26 #include "hw/hw.h"
27 #include "hw/ppc/ppc.h"
28 #include "hw/ppc/ppc4xx.h"
29 #include "hw/boards.h"
30 #include "qemu/log.h"
31 #include "exec/address-spaces.h"
32 
33 #define DEBUG_UIC
34 
35 
36 #ifdef DEBUG_UIC
37 #  define LOG_UIC(...) qemu_log_mask(CPU_LOG_INT, ## __VA_ARGS__)
38 #else
39 #  define LOG_UIC(...) do { } while (0)
40 #endif
41 
42 static void ppc4xx_reset(void *opaque)
43 {
44     PowerPCCPU *cpu = opaque;
45 
46     cpu_reset(CPU(cpu));
47 }
48 
49 /*****************************************************************************/
50 /* Generic PowerPC 4xx processor instantiation */
51 PowerPCCPU *ppc4xx_init(const char *cpu_model,
52                         clk_setup_t *cpu_clk, clk_setup_t *tb_clk,
53                         uint32_t sysclk)
54 {
55     PowerPCCPU *cpu;
56     CPUPPCState *env;
57 
58     /* init CPUs */
59     cpu = cpu_ppc_init(cpu_model);
60     if (cpu == NULL) {
61         fprintf(stderr, "Unable to find PowerPC %s CPU definition\n",
62                 cpu_model);
63         exit(1);
64     }
65     env = &cpu->env;
66 
67     cpu_clk->cb = NULL; /* We don't care about CPU clock frequency changes */
68     cpu_clk->opaque = env;
69     /* Set time-base frequency to sysclk */
70     tb_clk->cb = ppc_40x_timers_init(env, sysclk, PPC_INTERRUPT_PIT);
71     tb_clk->opaque = env;
72     ppc_dcr_init(env, NULL, NULL);
73     /* Register qemu callbacks */
74     qemu_register_reset(ppc4xx_reset, cpu);
75 
76     return cpu;
77 }
78 
79 /*****************************************************************************/
80 /* "Universal" Interrupt controller */
81 enum {
82     DCR_UICSR  = 0x000,
83     DCR_UICSRS = 0x001,
84     DCR_UICER  = 0x002,
85     DCR_UICCR  = 0x003,
86     DCR_UICPR  = 0x004,
87     DCR_UICTR  = 0x005,
88     DCR_UICMSR = 0x006,
89     DCR_UICVR  = 0x007,
90     DCR_UICVCR = 0x008,
91     DCR_UICMAX = 0x009,
92 };
93 
94 #define UIC_MAX_IRQ 32
95 typedef struct ppcuic_t ppcuic_t;
96 struct ppcuic_t {
97     uint32_t dcr_base;
98     int use_vectors;
99     uint32_t level;  /* Remembers the state of level-triggered interrupts. */
100     uint32_t uicsr;  /* Status register */
101     uint32_t uicer;  /* Enable register */
102     uint32_t uiccr;  /* Critical register */
103     uint32_t uicpr;  /* Polarity register */
104     uint32_t uictr;  /* Triggering register */
105     uint32_t uicvcr; /* Vector configuration register */
106     uint32_t uicvr;
107     qemu_irq *irqs;
108 };
109 
110 static void ppcuic_trigger_irq (ppcuic_t *uic)
111 {
112     uint32_t ir, cr;
113     int start, end, inc, i;
114 
115     /* Trigger interrupt if any is pending */
116     ir = uic->uicsr & uic->uicer & (~uic->uiccr);
117     cr = uic->uicsr & uic->uicer & uic->uiccr;
118     LOG_UIC("%s: uicsr %08" PRIx32 " uicer %08" PRIx32
119                 " uiccr %08" PRIx32 "\n"
120                 "   %08" PRIx32 " ir %08" PRIx32 " cr %08" PRIx32 "\n",
121                 __func__, uic->uicsr, uic->uicer, uic->uiccr,
122                 uic->uicsr & uic->uicer, ir, cr);
123     if (ir != 0x0000000) {
124         LOG_UIC("Raise UIC interrupt\n");
125         qemu_irq_raise(uic->irqs[PPCUIC_OUTPUT_INT]);
126     } else {
127         LOG_UIC("Lower UIC interrupt\n");
128         qemu_irq_lower(uic->irqs[PPCUIC_OUTPUT_INT]);
129     }
130     /* Trigger critical interrupt if any is pending and update vector */
131     if (cr != 0x0000000) {
132         qemu_irq_raise(uic->irqs[PPCUIC_OUTPUT_CINT]);
133         if (uic->use_vectors) {
134             /* Compute critical IRQ vector */
135             if (uic->uicvcr & 1) {
136                 start = 31;
137                 end = 0;
138                 inc = -1;
139             } else {
140                 start = 0;
141                 end = 31;
142                 inc = 1;
143             }
144             uic->uicvr = uic->uicvcr & 0xFFFFFFFC;
145             for (i = start; i <= end; i += inc) {
146                 if (cr & (1 << i)) {
147                     uic->uicvr += (i - start) * 512 * inc;
148                     break;
149                 }
150             }
151         }
152         LOG_UIC("Raise UIC critical interrupt - "
153                     "vector %08" PRIx32 "\n", uic->uicvr);
154     } else {
155         LOG_UIC("Lower UIC critical interrupt\n");
156         qemu_irq_lower(uic->irqs[PPCUIC_OUTPUT_CINT]);
157         uic->uicvr = 0x00000000;
158     }
159 }
160 
161 static void ppcuic_set_irq (void *opaque, int irq_num, int level)
162 {
163     ppcuic_t *uic;
164     uint32_t mask, sr;
165 
166     uic = opaque;
167     mask = 1U << (31-irq_num);
168     LOG_UIC("%s: irq %d level %d uicsr %08" PRIx32
169                 " mask %08" PRIx32 " => %08" PRIx32 " %08" PRIx32 "\n",
170                 __func__, irq_num, level,
171                 uic->uicsr, mask, uic->uicsr & mask, level << irq_num);
172     if (irq_num < 0 || irq_num > 31)
173         return;
174     sr = uic->uicsr;
175 
176     /* Update status register */
177     if (uic->uictr & mask) {
178         /* Edge sensitive interrupt */
179         if (level == 1)
180             uic->uicsr |= mask;
181     } else {
182         /* Level sensitive interrupt */
183         if (level == 1) {
184             uic->uicsr |= mask;
185             uic->level |= mask;
186         } else {
187             uic->uicsr &= ~mask;
188             uic->level &= ~mask;
189         }
190     }
191     LOG_UIC("%s: irq %d level %d sr %" PRIx32 " => "
192                 "%08" PRIx32 "\n", __func__, irq_num, level, uic->uicsr, sr);
193     if (sr != uic->uicsr)
194         ppcuic_trigger_irq(uic);
195 }
196 
197 static uint32_t dcr_read_uic (void *opaque, int dcrn)
198 {
199     ppcuic_t *uic;
200     uint32_t ret;
201 
202     uic = opaque;
203     dcrn -= uic->dcr_base;
204     switch (dcrn) {
205     case DCR_UICSR:
206     case DCR_UICSRS:
207         ret = uic->uicsr;
208         break;
209     case DCR_UICER:
210         ret = uic->uicer;
211         break;
212     case DCR_UICCR:
213         ret = uic->uiccr;
214         break;
215     case DCR_UICPR:
216         ret = uic->uicpr;
217         break;
218     case DCR_UICTR:
219         ret = uic->uictr;
220         break;
221     case DCR_UICMSR:
222         ret = uic->uicsr & uic->uicer;
223         break;
224     case DCR_UICVR:
225         if (!uic->use_vectors)
226             goto no_read;
227         ret = uic->uicvr;
228         break;
229     case DCR_UICVCR:
230         if (!uic->use_vectors)
231             goto no_read;
232         ret = uic->uicvcr;
233         break;
234     default:
235     no_read:
236         ret = 0x00000000;
237         break;
238     }
239 
240     return ret;
241 }
242 
243 static void dcr_write_uic (void *opaque, int dcrn, uint32_t val)
244 {
245     ppcuic_t *uic;
246 
247     uic = opaque;
248     dcrn -= uic->dcr_base;
249     LOG_UIC("%s: dcr %d val 0x%x\n", __func__, dcrn, val);
250     switch (dcrn) {
251     case DCR_UICSR:
252         uic->uicsr &= ~val;
253         uic->uicsr |= uic->level;
254         ppcuic_trigger_irq(uic);
255         break;
256     case DCR_UICSRS:
257         uic->uicsr |= val;
258         ppcuic_trigger_irq(uic);
259         break;
260     case DCR_UICER:
261         uic->uicer = val;
262         ppcuic_trigger_irq(uic);
263         break;
264     case DCR_UICCR:
265         uic->uiccr = val;
266         ppcuic_trigger_irq(uic);
267         break;
268     case DCR_UICPR:
269         uic->uicpr = val;
270         break;
271     case DCR_UICTR:
272         uic->uictr = val;
273         ppcuic_trigger_irq(uic);
274         break;
275     case DCR_UICMSR:
276         break;
277     case DCR_UICVR:
278         break;
279     case DCR_UICVCR:
280         uic->uicvcr = val & 0xFFFFFFFD;
281         ppcuic_trigger_irq(uic);
282         break;
283     }
284 }
285 
286 static void ppcuic_reset (void *opaque)
287 {
288     ppcuic_t *uic;
289 
290     uic = opaque;
291     uic->uiccr = 0x00000000;
292     uic->uicer = 0x00000000;
293     uic->uicpr = 0x00000000;
294     uic->uicsr = 0x00000000;
295     uic->uictr = 0x00000000;
296     if (uic->use_vectors) {
297         uic->uicvcr = 0x00000000;
298         uic->uicvr = 0x0000000;
299     }
300 }
301 
302 qemu_irq *ppcuic_init (CPUPPCState *env, qemu_irq *irqs,
303                        uint32_t dcr_base, int has_ssr, int has_vr)
304 {
305     ppcuic_t *uic;
306     int i;
307 
308     uic = g_malloc0(sizeof(ppcuic_t));
309     uic->dcr_base = dcr_base;
310     uic->irqs = irqs;
311     if (has_vr)
312         uic->use_vectors = 1;
313     for (i = 0; i < DCR_UICMAX; i++) {
314         ppc_dcr_register(env, dcr_base + i, uic,
315                          &dcr_read_uic, &dcr_write_uic);
316     }
317     qemu_register_reset(ppcuic_reset, uic);
318 
319     return qemu_allocate_irqs(&ppcuic_set_irq, uic, UIC_MAX_IRQ);
320 }
321 
322 /*****************************************************************************/
323 /* SDRAM controller */
324 typedef struct ppc4xx_sdram_t ppc4xx_sdram_t;
325 struct ppc4xx_sdram_t {
326     uint32_t addr;
327     int nbanks;
328     MemoryRegion containers[4]; /* used for clipping */
329     MemoryRegion *ram_memories;
330     hwaddr ram_bases[4];
331     hwaddr ram_sizes[4];
332     uint32_t besr0;
333     uint32_t besr1;
334     uint32_t bear;
335     uint32_t cfg;
336     uint32_t status;
337     uint32_t rtr;
338     uint32_t pmit;
339     uint32_t bcr[4];
340     uint32_t tr;
341     uint32_t ecccfg;
342     uint32_t eccesr;
343     qemu_irq irq;
344 };
345 
346 enum {
347     SDRAM0_CFGADDR = 0x010,
348     SDRAM0_CFGDATA = 0x011,
349 };
350 
351 /* XXX: TOFIX: some patches have made this code become inconsistent:
352  *      there are type inconsistencies, mixing hwaddr, target_ulong
353  *      and uint32_t
354  */
355 static uint32_t sdram_bcr (hwaddr ram_base,
356                            hwaddr ram_size)
357 {
358     uint32_t bcr;
359 
360     switch (ram_size) {
361     case (4 * 1024 * 1024):
362         bcr = 0x00000000;
363         break;
364     case (8 * 1024 * 1024):
365         bcr = 0x00020000;
366         break;
367     case (16 * 1024 * 1024):
368         bcr = 0x00040000;
369         break;
370     case (32 * 1024 * 1024):
371         bcr = 0x00060000;
372         break;
373     case (64 * 1024 * 1024):
374         bcr = 0x00080000;
375         break;
376     case (128 * 1024 * 1024):
377         bcr = 0x000A0000;
378         break;
379     case (256 * 1024 * 1024):
380         bcr = 0x000C0000;
381         break;
382     default:
383         printf("%s: invalid RAM size " TARGET_FMT_plx "\n", __func__,
384                ram_size);
385         return 0x00000000;
386     }
387     bcr |= ram_base & 0xFF800000;
388     bcr |= 1;
389 
390     return bcr;
391 }
392 
393 static inline hwaddr sdram_base(uint32_t bcr)
394 {
395     return bcr & 0xFF800000;
396 }
397 
398 static target_ulong sdram_size (uint32_t bcr)
399 {
400     target_ulong size;
401     int sh;
402 
403     sh = (bcr >> 17) & 0x7;
404     if (sh == 7)
405         size = -1;
406     else
407         size = (4 * 1024 * 1024) << sh;
408 
409     return size;
410 }
411 
412 static void sdram_set_bcr(ppc4xx_sdram_t *sdram,
413                           uint32_t *bcrp, uint32_t bcr, int enabled)
414 {
415     unsigned n = bcrp - sdram->bcr;
416 
417     if (*bcrp & 0x00000001) {
418         /* Unmap RAM */
419 #ifdef DEBUG_SDRAM
420         printf("%s: unmap RAM area " TARGET_FMT_plx " " TARGET_FMT_lx "\n",
421                __func__, sdram_base(*bcrp), sdram_size(*bcrp));
422 #endif
423         memory_region_del_subregion(get_system_memory(),
424                                     &sdram->containers[n]);
425         memory_region_del_subregion(&sdram->containers[n],
426                                     &sdram->ram_memories[n]);
427         object_unparent(OBJECT(&sdram->containers[n]));
428     }
429     *bcrp = bcr & 0xFFDEE001;
430     if (enabled && (bcr & 0x00000001)) {
431 #ifdef DEBUG_SDRAM
432         printf("%s: Map RAM area " TARGET_FMT_plx " " TARGET_FMT_lx "\n",
433                __func__, sdram_base(bcr), sdram_size(bcr));
434 #endif
435         memory_region_init(&sdram->containers[n], NULL, "sdram-containers",
436                            sdram_size(bcr));
437         memory_region_add_subregion(&sdram->containers[n], 0,
438                                     &sdram->ram_memories[n]);
439         memory_region_add_subregion(get_system_memory(),
440                                     sdram_base(bcr),
441                                     &sdram->containers[n]);
442     }
443 }
444 
445 static void sdram_map_bcr (ppc4xx_sdram_t *sdram)
446 {
447     int i;
448 
449     for (i = 0; i < sdram->nbanks; i++) {
450         if (sdram->ram_sizes[i] != 0) {
451             sdram_set_bcr(sdram,
452                           &sdram->bcr[i],
453                           sdram_bcr(sdram->ram_bases[i], sdram->ram_sizes[i]),
454                           1);
455         } else {
456             sdram_set_bcr(sdram, &sdram->bcr[i], 0x00000000, 0);
457         }
458     }
459 }
460 
461 static void sdram_unmap_bcr (ppc4xx_sdram_t *sdram)
462 {
463     int i;
464 
465     for (i = 0; i < sdram->nbanks; i++) {
466 #ifdef DEBUG_SDRAM
467         printf("%s: Unmap RAM area " TARGET_FMT_plx " " TARGET_FMT_lx "\n",
468                __func__, sdram_base(sdram->bcr[i]), sdram_size(sdram->bcr[i]));
469 #endif
470         memory_region_del_subregion(get_system_memory(),
471                                     &sdram->ram_memories[i]);
472     }
473 }
474 
475 static uint32_t dcr_read_sdram (void *opaque, int dcrn)
476 {
477     ppc4xx_sdram_t *sdram;
478     uint32_t ret;
479 
480     sdram = opaque;
481     switch (dcrn) {
482     case SDRAM0_CFGADDR:
483         ret = sdram->addr;
484         break;
485     case SDRAM0_CFGDATA:
486         switch (sdram->addr) {
487         case 0x00: /* SDRAM_BESR0 */
488             ret = sdram->besr0;
489             break;
490         case 0x08: /* SDRAM_BESR1 */
491             ret = sdram->besr1;
492             break;
493         case 0x10: /* SDRAM_BEAR */
494             ret = sdram->bear;
495             break;
496         case 0x20: /* SDRAM_CFG */
497             ret = sdram->cfg;
498             break;
499         case 0x24: /* SDRAM_STATUS */
500             ret = sdram->status;
501             break;
502         case 0x30: /* SDRAM_RTR */
503             ret = sdram->rtr;
504             break;
505         case 0x34: /* SDRAM_PMIT */
506             ret = sdram->pmit;
507             break;
508         case 0x40: /* SDRAM_B0CR */
509             ret = sdram->bcr[0];
510             break;
511         case 0x44: /* SDRAM_B1CR */
512             ret = sdram->bcr[1];
513             break;
514         case 0x48: /* SDRAM_B2CR */
515             ret = sdram->bcr[2];
516             break;
517         case 0x4C: /* SDRAM_B3CR */
518             ret = sdram->bcr[3];
519             break;
520         case 0x80: /* SDRAM_TR */
521             ret = -1; /* ? */
522             break;
523         case 0x94: /* SDRAM_ECCCFG */
524             ret = sdram->ecccfg;
525             break;
526         case 0x98: /* SDRAM_ECCESR */
527             ret = sdram->eccesr;
528             break;
529         default: /* Error */
530             ret = -1;
531             break;
532         }
533         break;
534     default:
535         /* Avoid gcc warning */
536         ret = 0x00000000;
537         break;
538     }
539 
540     return ret;
541 }
542 
543 static void dcr_write_sdram (void *opaque, int dcrn, uint32_t val)
544 {
545     ppc4xx_sdram_t *sdram;
546 
547     sdram = opaque;
548     switch (dcrn) {
549     case SDRAM0_CFGADDR:
550         sdram->addr = val;
551         break;
552     case SDRAM0_CFGDATA:
553         switch (sdram->addr) {
554         case 0x00: /* SDRAM_BESR0 */
555             sdram->besr0 &= ~val;
556             break;
557         case 0x08: /* SDRAM_BESR1 */
558             sdram->besr1 &= ~val;
559             break;
560         case 0x10: /* SDRAM_BEAR */
561             sdram->bear = val;
562             break;
563         case 0x20: /* SDRAM_CFG */
564             val &= 0xFFE00000;
565             if (!(sdram->cfg & 0x80000000) && (val & 0x80000000)) {
566 #ifdef DEBUG_SDRAM
567                 printf("%s: enable SDRAM controller\n", __func__);
568 #endif
569                 /* validate all RAM mappings */
570                 sdram_map_bcr(sdram);
571                 sdram->status &= ~0x80000000;
572             } else if ((sdram->cfg & 0x80000000) && !(val & 0x80000000)) {
573 #ifdef DEBUG_SDRAM
574                 printf("%s: disable SDRAM controller\n", __func__);
575 #endif
576                 /* invalidate all RAM mappings */
577                 sdram_unmap_bcr(sdram);
578                 sdram->status |= 0x80000000;
579             }
580             if (!(sdram->cfg & 0x40000000) && (val & 0x40000000))
581                 sdram->status |= 0x40000000;
582             else if ((sdram->cfg & 0x40000000) && !(val & 0x40000000))
583                 sdram->status &= ~0x40000000;
584             sdram->cfg = val;
585             break;
586         case 0x24: /* SDRAM_STATUS */
587             /* Read-only register */
588             break;
589         case 0x30: /* SDRAM_RTR */
590             sdram->rtr = val & 0x3FF80000;
591             break;
592         case 0x34: /* SDRAM_PMIT */
593             sdram->pmit = (val & 0xF8000000) | 0x07C00000;
594             break;
595         case 0x40: /* SDRAM_B0CR */
596             sdram_set_bcr(sdram, &sdram->bcr[0], val, sdram->cfg & 0x80000000);
597             break;
598         case 0x44: /* SDRAM_B1CR */
599             sdram_set_bcr(sdram, &sdram->bcr[1], val, sdram->cfg & 0x80000000);
600             break;
601         case 0x48: /* SDRAM_B2CR */
602             sdram_set_bcr(sdram, &sdram->bcr[2], val, sdram->cfg & 0x80000000);
603             break;
604         case 0x4C: /* SDRAM_B3CR */
605             sdram_set_bcr(sdram, &sdram->bcr[3], val, sdram->cfg & 0x80000000);
606             break;
607         case 0x80: /* SDRAM_TR */
608             sdram->tr = val & 0x018FC01F;
609             break;
610         case 0x94: /* SDRAM_ECCCFG */
611             sdram->ecccfg = val & 0x00F00000;
612             break;
613         case 0x98: /* SDRAM_ECCESR */
614             val &= 0xFFF0F000;
615             if (sdram->eccesr == 0 && val != 0)
616                 qemu_irq_raise(sdram->irq);
617             else if (sdram->eccesr != 0 && val == 0)
618                 qemu_irq_lower(sdram->irq);
619             sdram->eccesr = val;
620             break;
621         default: /* Error */
622             break;
623         }
624         break;
625     }
626 }
627 
628 static void sdram_reset (void *opaque)
629 {
630     ppc4xx_sdram_t *sdram;
631 
632     sdram = opaque;
633     sdram->addr = 0x00000000;
634     sdram->bear = 0x00000000;
635     sdram->besr0 = 0x00000000; /* No error */
636     sdram->besr1 = 0x00000000; /* No error */
637     sdram->cfg = 0x00000000;
638     sdram->ecccfg = 0x00000000; /* No ECC */
639     sdram->eccesr = 0x00000000; /* No error */
640     sdram->pmit = 0x07C00000;
641     sdram->rtr = 0x05F00000;
642     sdram->tr = 0x00854009;
643     /* We pre-initialize RAM banks */
644     sdram->status = 0x00000000;
645     sdram->cfg = 0x00800000;
646 }
647 
648 void ppc4xx_sdram_init (CPUPPCState *env, qemu_irq irq, int nbanks,
649                         MemoryRegion *ram_memories,
650                         hwaddr *ram_bases,
651                         hwaddr *ram_sizes,
652                         int do_init)
653 {
654     ppc4xx_sdram_t *sdram;
655 
656     sdram = g_malloc0(sizeof(ppc4xx_sdram_t));
657     sdram->irq = irq;
658     sdram->nbanks = nbanks;
659     sdram->ram_memories = ram_memories;
660     memset(sdram->ram_bases, 0, 4 * sizeof(hwaddr));
661     memcpy(sdram->ram_bases, ram_bases,
662            nbanks * sizeof(hwaddr));
663     memset(sdram->ram_sizes, 0, 4 * sizeof(hwaddr));
664     memcpy(sdram->ram_sizes, ram_sizes,
665            nbanks * sizeof(hwaddr));
666     qemu_register_reset(&sdram_reset, sdram);
667     ppc_dcr_register(env, SDRAM0_CFGADDR,
668                      sdram, &dcr_read_sdram, &dcr_write_sdram);
669     ppc_dcr_register(env, SDRAM0_CFGDATA,
670                      sdram, &dcr_read_sdram, &dcr_write_sdram);
671     if (do_init)
672         sdram_map_bcr(sdram);
673 }
674 
675 /* Fill in consecutive SDRAM banks with 'ram_size' bytes of memory.
676  *
677  * sdram_bank_sizes[] must be 0-terminated.
678  *
679  * The 4xx SDRAM controller supports a small number of banks, and each bank
680  * must be one of a small set of sizes. The number of banks and the supported
681  * sizes varies by SoC. */
682 ram_addr_t ppc4xx_sdram_adjust(ram_addr_t ram_size, int nr_banks,
683                                MemoryRegion ram_memories[],
684                                hwaddr ram_bases[],
685                                hwaddr ram_sizes[],
686                                const unsigned int sdram_bank_sizes[])
687 {
688     MemoryRegion *ram = g_malloc0(sizeof(*ram));
689     ram_addr_t size_left = ram_size;
690     ram_addr_t base = 0;
691     unsigned int bank_size;
692     int i;
693     int j;
694 
695     for (i = 0; i < nr_banks; i++) {
696         for (j = 0; sdram_bank_sizes[j] != 0; j++) {
697             bank_size = sdram_bank_sizes[j];
698             if (bank_size <= size_left) {
699                 size_left -= bank_size;
700             }
701         }
702         if (!size_left) {
703             /* No need to use the remaining banks. */
704             break;
705         }
706     }
707 
708     ram_size -= size_left;
709     if (size_left) {
710         printf("Truncating memory to %d MiB to fit SDRAM controller limits.\n",
711                (int)(ram_size >> 20));
712     }
713 
714     memory_region_allocate_system_memory(ram, NULL, "ppc4xx.sdram", ram_size);
715 
716     size_left = ram_size;
717     for (i = 0; i < nr_banks && size_left; i++) {
718         for (j = 0; sdram_bank_sizes[j] != 0; j++) {
719             bank_size = sdram_bank_sizes[j];
720 
721             if (bank_size <= size_left) {
722                 char name[32];
723                 snprintf(name, sizeof(name), "ppc4xx.sdram%d", i);
724                 memory_region_init_alias(&ram_memories[i], NULL, name, ram,
725                                          base, bank_size);
726                 ram_bases[i] = base;
727                 ram_sizes[i] = bank_size;
728                 base += bank_size;
729                 size_left -= bank_size;
730                 break;
731             }
732         }
733     }
734 
735     return ram_size;
736 }
737