xref: /openbmc/qemu/hw/ppc/ppc4xx_devs.c (revision 469b046e)
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 "hw/hw.h"
25 #include "hw/ppc/ppc.h"
26 #include "hw/ppc/ppc4xx.h"
27 #include "hw/boards.h"
28 #include "qemu/log.h"
29 #include "exec/address-spaces.h"
30 
31 #define DEBUG_UIC
32 
33 
34 #ifdef DEBUG_UIC
35 #  define LOG_UIC(...) qemu_log_mask(CPU_LOG_INT, ## __VA_ARGS__)
36 #else
37 #  define LOG_UIC(...) do { } while (0)
38 #endif
39 
40 static void ppc4xx_reset(void *opaque)
41 {
42     PowerPCCPU *cpu = opaque;
43 
44     cpu_reset(CPU(cpu));
45 }
46 
47 /*****************************************************************************/
48 /* Generic PowerPC 4xx processor instantiation */
49 PowerPCCPU *ppc4xx_init(const char *cpu_model,
50                         clk_setup_t *cpu_clk, clk_setup_t *tb_clk,
51                         uint32_t sysclk)
52 {
53     PowerPCCPU *cpu;
54     CPUPPCState *env;
55 
56     /* init CPUs */
57     cpu = cpu_ppc_init(cpu_model);
58     if (cpu == NULL) {
59         fprintf(stderr, "Unable to find PowerPC %s CPU definition\n",
60                 cpu_model);
61         exit(1);
62     }
63     env = &cpu->env;
64 
65     cpu_clk->cb = NULL; /* We don't care about CPU clock frequency changes */
66     cpu_clk->opaque = env;
67     /* Set time-base frequency to sysclk */
68     tb_clk->cb = ppc_40x_timers_init(env, sysclk, PPC_INTERRUPT_PIT);
69     tb_clk->opaque = env;
70     ppc_dcr_init(env, NULL, NULL);
71     /* Register qemu callbacks */
72     qemu_register_reset(ppc4xx_reset, cpu);
73 
74     return cpu;
75 }
76 
77 /*****************************************************************************/
78 /* "Universal" Interrupt controller */
79 enum {
80     DCR_UICSR  = 0x000,
81     DCR_UICSRS = 0x001,
82     DCR_UICER  = 0x002,
83     DCR_UICCR  = 0x003,
84     DCR_UICPR  = 0x004,
85     DCR_UICTR  = 0x005,
86     DCR_UICMSR = 0x006,
87     DCR_UICVR  = 0x007,
88     DCR_UICVCR = 0x008,
89     DCR_UICMAX = 0x009,
90 };
91 
92 #define UIC_MAX_IRQ 32
93 typedef struct ppcuic_t ppcuic_t;
94 struct ppcuic_t {
95     uint32_t dcr_base;
96     int use_vectors;
97     uint32_t level;  /* Remembers the state of level-triggered interrupts. */
98     uint32_t uicsr;  /* Status register */
99     uint32_t uicer;  /* Enable register */
100     uint32_t uiccr;  /* Critical register */
101     uint32_t uicpr;  /* Polarity register */
102     uint32_t uictr;  /* Triggering register */
103     uint32_t uicvcr; /* Vector configuration register */
104     uint32_t uicvr;
105     qemu_irq *irqs;
106 };
107 
108 static void ppcuic_trigger_irq (ppcuic_t *uic)
109 {
110     uint32_t ir, cr;
111     int start, end, inc, i;
112 
113     /* Trigger interrupt if any is pending */
114     ir = uic->uicsr & uic->uicer & (~uic->uiccr);
115     cr = uic->uicsr & uic->uicer & uic->uiccr;
116     LOG_UIC("%s: uicsr %08" PRIx32 " uicer %08" PRIx32
117                 " uiccr %08" PRIx32 "\n"
118                 "   %08" PRIx32 " ir %08" PRIx32 " cr %08" PRIx32 "\n",
119                 __func__, uic->uicsr, uic->uicer, uic->uiccr,
120                 uic->uicsr & uic->uicer, ir, cr);
121     if (ir != 0x0000000) {
122         LOG_UIC("Raise UIC interrupt\n");
123         qemu_irq_raise(uic->irqs[PPCUIC_OUTPUT_INT]);
124     } else {
125         LOG_UIC("Lower UIC interrupt\n");
126         qemu_irq_lower(uic->irqs[PPCUIC_OUTPUT_INT]);
127     }
128     /* Trigger critical interrupt if any is pending and update vector */
129     if (cr != 0x0000000) {
130         qemu_irq_raise(uic->irqs[PPCUIC_OUTPUT_CINT]);
131         if (uic->use_vectors) {
132             /* Compute critical IRQ vector */
133             if (uic->uicvcr & 1) {
134                 start = 31;
135                 end = 0;
136                 inc = -1;
137             } else {
138                 start = 0;
139                 end = 31;
140                 inc = 1;
141             }
142             uic->uicvr = uic->uicvcr & 0xFFFFFFFC;
143             for (i = start; i <= end; i += inc) {
144                 if (cr & (1 << i)) {
145                     uic->uicvr += (i - start) * 512 * inc;
146                     break;
147                 }
148             }
149         }
150         LOG_UIC("Raise UIC critical interrupt - "
151                     "vector %08" PRIx32 "\n", uic->uicvr);
152     } else {
153         LOG_UIC("Lower UIC critical interrupt\n");
154         qemu_irq_lower(uic->irqs[PPCUIC_OUTPUT_CINT]);
155         uic->uicvr = 0x00000000;
156     }
157 }
158 
159 static void ppcuic_set_irq (void *opaque, int irq_num, int level)
160 {
161     ppcuic_t *uic;
162     uint32_t mask, sr;
163 
164     uic = opaque;
165     mask = 1U << (31-irq_num);
166     LOG_UIC("%s: irq %d level %d uicsr %08" PRIx32
167                 " mask %08" PRIx32 " => %08" PRIx32 " %08" PRIx32 "\n",
168                 __func__, irq_num, level,
169                 uic->uicsr, mask, uic->uicsr & mask, level << irq_num);
170     if (irq_num < 0 || irq_num > 31)
171         return;
172     sr = uic->uicsr;
173 
174     /* Update status register */
175     if (uic->uictr & mask) {
176         /* Edge sensitive interrupt */
177         if (level == 1)
178             uic->uicsr |= mask;
179     } else {
180         /* Level sensitive interrupt */
181         if (level == 1) {
182             uic->uicsr |= mask;
183             uic->level |= mask;
184         } else {
185             uic->uicsr &= ~mask;
186             uic->level &= ~mask;
187         }
188     }
189     LOG_UIC("%s: irq %d level %d sr %" PRIx32 " => "
190                 "%08" PRIx32 "\n", __func__, irq_num, level, uic->uicsr, sr);
191     if (sr != uic->uicsr)
192         ppcuic_trigger_irq(uic);
193 }
194 
195 static uint32_t dcr_read_uic (void *opaque, int dcrn)
196 {
197     ppcuic_t *uic;
198     uint32_t ret;
199 
200     uic = opaque;
201     dcrn -= uic->dcr_base;
202     switch (dcrn) {
203     case DCR_UICSR:
204     case DCR_UICSRS:
205         ret = uic->uicsr;
206         break;
207     case DCR_UICER:
208         ret = uic->uicer;
209         break;
210     case DCR_UICCR:
211         ret = uic->uiccr;
212         break;
213     case DCR_UICPR:
214         ret = uic->uicpr;
215         break;
216     case DCR_UICTR:
217         ret = uic->uictr;
218         break;
219     case DCR_UICMSR:
220         ret = uic->uicsr & uic->uicer;
221         break;
222     case DCR_UICVR:
223         if (!uic->use_vectors)
224             goto no_read;
225         ret = uic->uicvr;
226         break;
227     case DCR_UICVCR:
228         if (!uic->use_vectors)
229             goto no_read;
230         ret = uic->uicvcr;
231         break;
232     default:
233     no_read:
234         ret = 0x00000000;
235         break;
236     }
237 
238     return ret;
239 }
240 
241 static void dcr_write_uic (void *opaque, int dcrn, uint32_t val)
242 {
243     ppcuic_t *uic;
244 
245     uic = opaque;
246     dcrn -= uic->dcr_base;
247     LOG_UIC("%s: dcr %d val 0x%x\n", __func__, dcrn, val);
248     switch (dcrn) {
249     case DCR_UICSR:
250         uic->uicsr &= ~val;
251         uic->uicsr |= uic->level;
252         ppcuic_trigger_irq(uic);
253         break;
254     case DCR_UICSRS:
255         uic->uicsr |= val;
256         ppcuic_trigger_irq(uic);
257         break;
258     case DCR_UICER:
259         uic->uicer = val;
260         ppcuic_trigger_irq(uic);
261         break;
262     case DCR_UICCR:
263         uic->uiccr = val;
264         ppcuic_trigger_irq(uic);
265         break;
266     case DCR_UICPR:
267         uic->uicpr = val;
268         break;
269     case DCR_UICTR:
270         uic->uictr = val;
271         ppcuic_trigger_irq(uic);
272         break;
273     case DCR_UICMSR:
274         break;
275     case DCR_UICVR:
276         break;
277     case DCR_UICVCR:
278         uic->uicvcr = val & 0xFFFFFFFD;
279         ppcuic_trigger_irq(uic);
280         break;
281     }
282 }
283 
284 static void ppcuic_reset (void *opaque)
285 {
286     ppcuic_t *uic;
287 
288     uic = opaque;
289     uic->uiccr = 0x00000000;
290     uic->uicer = 0x00000000;
291     uic->uicpr = 0x00000000;
292     uic->uicsr = 0x00000000;
293     uic->uictr = 0x00000000;
294     if (uic->use_vectors) {
295         uic->uicvcr = 0x00000000;
296         uic->uicvr = 0x0000000;
297     }
298 }
299 
300 qemu_irq *ppcuic_init (CPUPPCState *env, qemu_irq *irqs,
301                        uint32_t dcr_base, int has_ssr, int has_vr)
302 {
303     ppcuic_t *uic;
304     int i;
305 
306     uic = g_malloc0(sizeof(ppcuic_t));
307     uic->dcr_base = dcr_base;
308     uic->irqs = irqs;
309     if (has_vr)
310         uic->use_vectors = 1;
311     for (i = 0; i < DCR_UICMAX; i++) {
312         ppc_dcr_register(env, dcr_base + i, uic,
313                          &dcr_read_uic, &dcr_write_uic);
314     }
315     qemu_register_reset(ppcuic_reset, uic);
316 
317     return qemu_allocate_irqs(&ppcuic_set_irq, uic, UIC_MAX_IRQ);
318 }
319 
320 /*****************************************************************************/
321 /* SDRAM controller */
322 typedef struct ppc4xx_sdram_t ppc4xx_sdram_t;
323 struct ppc4xx_sdram_t {
324     uint32_t addr;
325     int nbanks;
326     MemoryRegion containers[4]; /* used for clipping */
327     MemoryRegion *ram_memories;
328     hwaddr ram_bases[4];
329     hwaddr ram_sizes[4];
330     uint32_t besr0;
331     uint32_t besr1;
332     uint32_t bear;
333     uint32_t cfg;
334     uint32_t status;
335     uint32_t rtr;
336     uint32_t pmit;
337     uint32_t bcr[4];
338     uint32_t tr;
339     uint32_t ecccfg;
340     uint32_t eccesr;
341     qemu_irq irq;
342 };
343 
344 enum {
345     SDRAM0_CFGADDR = 0x010,
346     SDRAM0_CFGDATA = 0x011,
347 };
348 
349 /* XXX: TOFIX: some patches have made this code become inconsistent:
350  *      there are type inconsistencies, mixing hwaddr, target_ulong
351  *      and uint32_t
352  */
353 static uint32_t sdram_bcr (hwaddr ram_base,
354                            hwaddr ram_size)
355 {
356     uint32_t bcr;
357 
358     switch (ram_size) {
359     case (4 * 1024 * 1024):
360         bcr = 0x00000000;
361         break;
362     case (8 * 1024 * 1024):
363         bcr = 0x00020000;
364         break;
365     case (16 * 1024 * 1024):
366         bcr = 0x00040000;
367         break;
368     case (32 * 1024 * 1024):
369         bcr = 0x00060000;
370         break;
371     case (64 * 1024 * 1024):
372         bcr = 0x00080000;
373         break;
374     case (128 * 1024 * 1024):
375         bcr = 0x000A0000;
376         break;
377     case (256 * 1024 * 1024):
378         bcr = 0x000C0000;
379         break;
380     default:
381         printf("%s: invalid RAM size " TARGET_FMT_plx "\n", __func__,
382                ram_size);
383         return 0x00000000;
384     }
385     bcr |= ram_base & 0xFF800000;
386     bcr |= 1;
387 
388     return bcr;
389 }
390 
391 static inline hwaddr sdram_base(uint32_t bcr)
392 {
393     return bcr & 0xFF800000;
394 }
395 
396 static target_ulong sdram_size (uint32_t bcr)
397 {
398     target_ulong size;
399     int sh;
400 
401     sh = (bcr >> 17) & 0x7;
402     if (sh == 7)
403         size = -1;
404     else
405         size = (4 * 1024 * 1024) << sh;
406 
407     return size;
408 }
409 
410 static void sdram_set_bcr(ppc4xx_sdram_t *sdram,
411                           uint32_t *bcrp, uint32_t bcr, int enabled)
412 {
413     unsigned n = bcrp - sdram->bcr;
414 
415     if (*bcrp & 0x00000001) {
416         /* Unmap RAM */
417 #ifdef DEBUG_SDRAM
418         printf("%s: unmap RAM area " TARGET_FMT_plx " " TARGET_FMT_lx "\n",
419                __func__, sdram_base(*bcrp), sdram_size(*bcrp));
420 #endif
421         memory_region_del_subregion(get_system_memory(),
422                                     &sdram->containers[n]);
423         memory_region_del_subregion(&sdram->containers[n],
424                                     &sdram->ram_memories[n]);
425         object_unparent(OBJECT(&sdram->containers[n]));
426     }
427     *bcrp = bcr & 0xFFDEE001;
428     if (enabled && (bcr & 0x00000001)) {
429 #ifdef DEBUG_SDRAM
430         printf("%s: Map RAM area " TARGET_FMT_plx " " TARGET_FMT_lx "\n",
431                __func__, sdram_base(bcr), sdram_size(bcr));
432 #endif
433         memory_region_init(&sdram->containers[n], NULL, "sdram-containers",
434                            sdram_size(bcr));
435         memory_region_add_subregion(&sdram->containers[n], 0,
436                                     &sdram->ram_memories[n]);
437         memory_region_add_subregion(get_system_memory(),
438                                     sdram_base(bcr),
439                                     &sdram->containers[n]);
440     }
441 }
442 
443 static void sdram_map_bcr (ppc4xx_sdram_t *sdram)
444 {
445     int i;
446 
447     for (i = 0; i < sdram->nbanks; i++) {
448         if (sdram->ram_sizes[i] != 0) {
449             sdram_set_bcr(sdram,
450                           &sdram->bcr[i],
451                           sdram_bcr(sdram->ram_bases[i], sdram->ram_sizes[i]),
452                           1);
453         } else {
454             sdram_set_bcr(sdram, &sdram->bcr[i], 0x00000000, 0);
455         }
456     }
457 }
458 
459 static void sdram_unmap_bcr (ppc4xx_sdram_t *sdram)
460 {
461     int i;
462 
463     for (i = 0; i < sdram->nbanks; i++) {
464 #ifdef DEBUG_SDRAM
465         printf("%s: Unmap RAM area " TARGET_FMT_plx " " TARGET_FMT_lx "\n",
466                __func__, sdram_base(sdram->bcr[i]), sdram_size(sdram->bcr[i]));
467 #endif
468         memory_region_del_subregion(get_system_memory(),
469                                     &sdram->ram_memories[i]);
470     }
471 }
472 
473 static uint32_t dcr_read_sdram (void *opaque, int dcrn)
474 {
475     ppc4xx_sdram_t *sdram;
476     uint32_t ret;
477 
478     sdram = opaque;
479     switch (dcrn) {
480     case SDRAM0_CFGADDR:
481         ret = sdram->addr;
482         break;
483     case SDRAM0_CFGDATA:
484         switch (sdram->addr) {
485         case 0x00: /* SDRAM_BESR0 */
486             ret = sdram->besr0;
487             break;
488         case 0x08: /* SDRAM_BESR1 */
489             ret = sdram->besr1;
490             break;
491         case 0x10: /* SDRAM_BEAR */
492             ret = sdram->bear;
493             break;
494         case 0x20: /* SDRAM_CFG */
495             ret = sdram->cfg;
496             break;
497         case 0x24: /* SDRAM_STATUS */
498             ret = sdram->status;
499             break;
500         case 0x30: /* SDRAM_RTR */
501             ret = sdram->rtr;
502             break;
503         case 0x34: /* SDRAM_PMIT */
504             ret = sdram->pmit;
505             break;
506         case 0x40: /* SDRAM_B0CR */
507             ret = sdram->bcr[0];
508             break;
509         case 0x44: /* SDRAM_B1CR */
510             ret = sdram->bcr[1];
511             break;
512         case 0x48: /* SDRAM_B2CR */
513             ret = sdram->bcr[2];
514             break;
515         case 0x4C: /* SDRAM_B3CR */
516             ret = sdram->bcr[3];
517             break;
518         case 0x80: /* SDRAM_TR */
519             ret = -1; /* ? */
520             break;
521         case 0x94: /* SDRAM_ECCCFG */
522             ret = sdram->ecccfg;
523             break;
524         case 0x98: /* SDRAM_ECCESR */
525             ret = sdram->eccesr;
526             break;
527         default: /* Error */
528             ret = -1;
529             break;
530         }
531         break;
532     default:
533         /* Avoid gcc warning */
534         ret = 0x00000000;
535         break;
536     }
537 
538     return ret;
539 }
540 
541 static void dcr_write_sdram (void *opaque, int dcrn, uint32_t val)
542 {
543     ppc4xx_sdram_t *sdram;
544 
545     sdram = opaque;
546     switch (dcrn) {
547     case SDRAM0_CFGADDR:
548         sdram->addr = val;
549         break;
550     case SDRAM0_CFGDATA:
551         switch (sdram->addr) {
552         case 0x00: /* SDRAM_BESR0 */
553             sdram->besr0 &= ~val;
554             break;
555         case 0x08: /* SDRAM_BESR1 */
556             sdram->besr1 &= ~val;
557             break;
558         case 0x10: /* SDRAM_BEAR */
559             sdram->bear = val;
560             break;
561         case 0x20: /* SDRAM_CFG */
562             val &= 0xFFE00000;
563             if (!(sdram->cfg & 0x80000000) && (val & 0x80000000)) {
564 #ifdef DEBUG_SDRAM
565                 printf("%s: enable SDRAM controller\n", __func__);
566 #endif
567                 /* validate all RAM mappings */
568                 sdram_map_bcr(sdram);
569                 sdram->status &= ~0x80000000;
570             } else if ((sdram->cfg & 0x80000000) && !(val & 0x80000000)) {
571 #ifdef DEBUG_SDRAM
572                 printf("%s: disable SDRAM controller\n", __func__);
573 #endif
574                 /* invalidate all RAM mappings */
575                 sdram_unmap_bcr(sdram);
576                 sdram->status |= 0x80000000;
577             }
578             if (!(sdram->cfg & 0x40000000) && (val & 0x40000000))
579                 sdram->status |= 0x40000000;
580             else if ((sdram->cfg & 0x40000000) && !(val & 0x40000000))
581                 sdram->status &= ~0x40000000;
582             sdram->cfg = val;
583             break;
584         case 0x24: /* SDRAM_STATUS */
585             /* Read-only register */
586             break;
587         case 0x30: /* SDRAM_RTR */
588             sdram->rtr = val & 0x3FF80000;
589             break;
590         case 0x34: /* SDRAM_PMIT */
591             sdram->pmit = (val & 0xF8000000) | 0x07C00000;
592             break;
593         case 0x40: /* SDRAM_B0CR */
594             sdram_set_bcr(sdram, &sdram->bcr[0], val, sdram->cfg & 0x80000000);
595             break;
596         case 0x44: /* SDRAM_B1CR */
597             sdram_set_bcr(sdram, &sdram->bcr[1], val, sdram->cfg & 0x80000000);
598             break;
599         case 0x48: /* SDRAM_B2CR */
600             sdram_set_bcr(sdram, &sdram->bcr[2], val, sdram->cfg & 0x80000000);
601             break;
602         case 0x4C: /* SDRAM_B3CR */
603             sdram_set_bcr(sdram, &sdram->bcr[3], val, sdram->cfg & 0x80000000);
604             break;
605         case 0x80: /* SDRAM_TR */
606             sdram->tr = val & 0x018FC01F;
607             break;
608         case 0x94: /* SDRAM_ECCCFG */
609             sdram->ecccfg = val & 0x00F00000;
610             break;
611         case 0x98: /* SDRAM_ECCESR */
612             val &= 0xFFF0F000;
613             if (sdram->eccesr == 0 && val != 0)
614                 qemu_irq_raise(sdram->irq);
615             else if (sdram->eccesr != 0 && val == 0)
616                 qemu_irq_lower(sdram->irq);
617             sdram->eccesr = val;
618             break;
619         default: /* Error */
620             break;
621         }
622         break;
623     }
624 }
625 
626 static void sdram_reset (void *opaque)
627 {
628     ppc4xx_sdram_t *sdram;
629 
630     sdram = opaque;
631     sdram->addr = 0x00000000;
632     sdram->bear = 0x00000000;
633     sdram->besr0 = 0x00000000; /* No error */
634     sdram->besr1 = 0x00000000; /* No error */
635     sdram->cfg = 0x00000000;
636     sdram->ecccfg = 0x00000000; /* No ECC */
637     sdram->eccesr = 0x00000000; /* No error */
638     sdram->pmit = 0x07C00000;
639     sdram->rtr = 0x05F00000;
640     sdram->tr = 0x00854009;
641     /* We pre-initialize RAM banks */
642     sdram->status = 0x00000000;
643     sdram->cfg = 0x00800000;
644 }
645 
646 void ppc4xx_sdram_init (CPUPPCState *env, qemu_irq irq, int nbanks,
647                         MemoryRegion *ram_memories,
648                         hwaddr *ram_bases,
649                         hwaddr *ram_sizes,
650                         int do_init)
651 {
652     ppc4xx_sdram_t *sdram;
653 
654     sdram = g_malloc0(sizeof(ppc4xx_sdram_t));
655     sdram->irq = irq;
656     sdram->nbanks = nbanks;
657     sdram->ram_memories = ram_memories;
658     memset(sdram->ram_bases, 0, 4 * sizeof(hwaddr));
659     memcpy(sdram->ram_bases, ram_bases,
660            nbanks * sizeof(hwaddr));
661     memset(sdram->ram_sizes, 0, 4 * sizeof(hwaddr));
662     memcpy(sdram->ram_sizes, ram_sizes,
663            nbanks * sizeof(hwaddr));
664     qemu_register_reset(&sdram_reset, sdram);
665     ppc_dcr_register(env, SDRAM0_CFGADDR,
666                      sdram, &dcr_read_sdram, &dcr_write_sdram);
667     ppc_dcr_register(env, SDRAM0_CFGDATA,
668                      sdram, &dcr_read_sdram, &dcr_write_sdram);
669     if (do_init)
670         sdram_map_bcr(sdram);
671 }
672 
673 /* Fill in consecutive SDRAM banks with 'ram_size' bytes of memory.
674  *
675  * sdram_bank_sizes[] must be 0-terminated.
676  *
677  * The 4xx SDRAM controller supports a small number of banks, and each bank
678  * must be one of a small set of sizes. The number of banks and the supported
679  * sizes varies by SoC. */
680 ram_addr_t ppc4xx_sdram_adjust(ram_addr_t ram_size, int nr_banks,
681                                MemoryRegion ram_memories[],
682                                hwaddr ram_bases[],
683                                hwaddr ram_sizes[],
684                                const unsigned int sdram_bank_sizes[])
685 {
686     ram_addr_t size_left = ram_size;
687     ram_addr_t base = 0;
688     int i;
689     int j;
690 
691     for (i = 0; i < nr_banks; i++) {
692         for (j = 0; sdram_bank_sizes[j] != 0; j++) {
693             unsigned int bank_size = sdram_bank_sizes[j];
694 
695             if (bank_size <= size_left) {
696                 char name[32];
697                 snprintf(name, sizeof(name), "ppc4xx.sdram%d", i);
698                 memory_region_allocate_system_memory(&ram_memories[i], NULL,
699                                                      name, bank_size);
700                 ram_bases[i] = base;
701                 ram_sizes[i] = bank_size;
702                 base += bank_size;
703                 size_left -= bank_size;
704                 break;
705             }
706         }
707 
708         if (!size_left) {
709             /* No need to use the remaining banks. */
710             break;
711         }
712     }
713 
714     ram_size -= size_left;
715     if (size_left)
716         printf("Truncating memory to %d MiB to fit SDRAM controller limits.\n",
717                (int)(ram_size >> 20));
718 
719     return ram_size;
720 }
721