aboutsummaryrefslogtreecommitdiff
path: root/hw/ppc/ppc4xx_sdram.c
blob: c0c87ff636a6c3952b86f6e1720058ebb01140ab (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
/*
 * QEMU PowerPC 4xx embedded processors SDRAM controller emulation
 *
 * DDR SDRAM controller:
 * Copyright (c) 2007 Jocelyn Mayer
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * DDR2 SDRAM controller:
 * Copyright (c) 2012 François Revol
 * Copyright (c) 2016-2019 BALATON Zoltan
 *
 * This work is licensed under the GNU GPL license version 2 or later.
 */

#include "qemu/osdep.h"
#include "qemu/units.h"
#include "qapi/error.h"
#include "qemu/log.h"
#include "qemu/error-report.h"
#include "exec/address-spaces.h" /* get_system_memory() */
#include "hw/irq.h"
#include "hw/qdev-properties.h"
#include "hw/ppc/ppc4xx.h"
#include "trace.h"

/*****************************************************************************/
/* Shared functions */

/*
 * Split RAM between SDRAM banks.
 *
 * sdram_bank_sizes[] must be in descending order, that is sizes[i] > sizes[i+1]
 * and must be 0-terminated.
 *
 * The 4xx SDRAM controller supports a small number of banks, and each bank
 * must be one of a small set of sizes. The number of banks and the supported
 * sizes varies by SoC.
 */
static bool ppc4xx_sdram_banks(MemoryRegion *ram, int nr_banks,
                               Ppc4xxSdramBank ram_banks[],
                               const ram_addr_t sdram_bank_sizes[],
                               Error **errp)
{
    ERRP_GUARD();
    ram_addr_t size_left = memory_region_size(ram);
    ram_addr_t base = 0;
    ram_addr_t bank_size;
    int i;
    int j;

    for (i = 0; i < nr_banks; i++) {
        for (j = 0; sdram_bank_sizes[j] != 0; j++) {
            bank_size = sdram_bank_sizes[j];
            if (bank_size <= size_left) {
                char name[32];

                ram_banks[i].base = base;
                ram_banks[i].size = bank_size;
                base += bank_size;
                size_left -= bank_size;
                snprintf(name, sizeof(name), "ppc4xx.sdram%d", i);
                memory_region_init_alias(&ram_banks[i].ram, NULL, name, ram,
                                         ram_banks[i].base, ram_banks[i].size);
                break;
            }
        }
        if (!size_left) {
            /* No need to use the remaining banks. */
            break;
        }
    }

    if (size_left) {
        ram_addr_t used_size = memory_region_size(ram) - size_left;
        GString *s = g_string_new(NULL);

        for (i = 0; sdram_bank_sizes[i]; i++) {
            g_string_append_printf(s, "%" PRIi64 "%s",
                                   sdram_bank_sizes[i] / MiB,
                                   sdram_bank_sizes[i + 1] ? ", " : "");
        }
        error_setg(errp, "Invalid SDRAM banks");
        error_append_hint(errp, "at most %d bank%s of %s MiB each supported\n",
                          nr_banks, nr_banks == 1 ? "" : "s", s->str);
        error_append_hint(errp, "Possible valid RAM size: %" PRIi64 " MiB\n",
                  used_size ? used_size / MiB : sdram_bank_sizes[i - 1] / MiB);

        g_string_free(s, true);
        return false;
    }
    return true;
}

static void sdram_bank_map(Ppc4xxSdramBank *bank)
{
    trace_ppc4xx_sdram_map(bank->base, bank->size);
    memory_region_init(&bank->container, NULL, "sdram-container", bank->size);
    memory_region_add_subregion(&bank->container, 0, &bank->ram);
    memory_region_add_subregion(get_system_memory(), bank->base,
                                &bank->container);
}

static void sdram_bank_unmap(Ppc4xxSdramBank *bank)
{
    trace_ppc4xx_sdram_unmap(bank->base, bank->size);
    memory_region_del_subregion(get_system_memory(), &bank->container);
    memory_region_del_subregion(&bank->container, &bank->ram);
    object_unparent(OBJECT(&bank->container));
}

static void sdram_bank_set_bcr(Ppc4xxSdramBank *bank, uint32_t bcr,
                               hwaddr base, hwaddr size, int enabled)
{
    if (memory_region_is_mapped(&bank->container)) {
        sdram_bank_unmap(bank);
    }
    bank->bcr = bcr;
    bank->base = base;
    bank->size = size;
    if (enabled && (bcr & 1)) {
        sdram_bank_map(bank);
    }
}

enum {
    SDRAM0_CFGADDR = 0x010,
    SDRAM0_CFGDATA = 0x011,
};

/*****************************************************************************/
/* DDR SDRAM controller */
#define SDRAM_DDR_BCR_MASK 0xFFDEE001

static uint32_t sdram_ddr_bcr(hwaddr ram_base, hwaddr ram_size)
{
    uint32_t bcr;

    switch (ram_size) {
    case 4 * MiB:
        bcr = 0;
        break;
    case 8 * MiB:
        bcr = 0x20000;
        break;
    case 16 * MiB:
        bcr = 0x40000;
        break;
    case 32 * MiB:
        bcr = 0x60000;
        break;
    case 64 * MiB:
        bcr = 0x80000;
        break;
    case 128 * MiB:
        bcr = 0xA0000;
        break;
    case 256 * MiB:
        bcr = 0xC0000;
        break;
    default:
        qemu_log_mask(LOG_GUEST_ERROR,
                      "%s: invalid RAM size 0x%" HWADDR_PRIx "\n", __func__,
                      ram_size);
        return 0;
    }
    bcr |= ram_base & 0xFF800000;
    bcr |= 1;

    return bcr;
}

static inline hwaddr sdram_ddr_base(uint32_t bcr)
{
    return bcr & 0xFF800000;
}

static hwaddr sdram_ddr_size(uint32_t bcr)
{
    int sh = (bcr >> 17) & 0x7;

    if (sh == 7) {
        return -1;
    }

    return (4 * MiB) << sh;
}

static uint32_t sdram_ddr_dcr_read(void *opaque, int dcrn)
{
    Ppc4xxSdramDdrState *s = opaque;
    uint32_t ret;

    switch (dcrn) {
    case SDRAM0_CFGADDR:
        ret = s->addr;
        break;
    case SDRAM0_CFGDATA:
        switch (s->addr) {
        case 0x00: /* SDRAM_BESR0 */
            ret = s->besr0;
            break;
        case 0x08: /* SDRAM_BESR1 */
            ret = s->besr1;
            break;
        case 0x10: /* SDRAM_BEAR */
            ret = s->bear;
            break;
        case 0x20: /* SDRAM_CFG */
            ret = s->cfg;
            break;
        case 0x24: /* SDRAM_STATUS */
            ret = s->status;
            break;
        case 0x30: /* SDRAM_RTR */
            ret = s->rtr;
            break;
        case 0x34: /* SDRAM_PMIT */
            ret = s->pmit;
            break;
        case 0x40: /* SDRAM_B0CR */
            ret = s->bank[0].bcr;
            break;
        case 0x44: /* SDRAM_B1CR */
            ret = s->bank[1].bcr;
            break;
        case 0x48: /* SDRAM_B2CR */
            ret = s->bank[2].bcr;
            break;
        case 0x4C: /* SDRAM_B3CR */
            ret = s->bank[3].bcr;
            break;
        case 0x80: /* SDRAM_TR */
            ret = -1; /* ? */
            break;
        case 0x94: /* SDRAM_ECCCFG */
            ret = s->ecccfg;
            break;
        case 0x98: /* SDRAM_ECCESR */
            ret = s->eccesr;
            break;
        default: /* Error */
            ret = -1;
            break;
        }
        break;
    default:
        /* Avoid gcc warning */
        ret = 0;
        break;
    }

    return ret;
}

static void sdram_ddr_dcr_write(void *opaque, int dcrn, uint32_t val)
{
    Ppc4xxSdramDdrState *s = opaque;
    int i;

    switch (dcrn) {
    case SDRAM0_CFGADDR:
        s->addr = val;
        break;
    case SDRAM0_CFGDATA:
        switch (s->addr) {
        case 0x00: /* SDRAM_BESR0 */
            s->besr0 &= ~val;
            break;
        case 0x08: /* SDRAM_BESR1 */
            s->besr1 &= ~val;
            break;
        case 0x10: /* SDRAM_BEAR */
            s->bear = val;
            break;
        case 0x20: /* SDRAM_CFG */
            val &= 0xFFE00000;
            if (!(s->cfg & 0x80000000) && (val & 0x80000000)) {
                trace_ppc4xx_sdram_enable("enable");
                /* validate all RAM mappings */
                for (i = 0; i < s->nbanks; i++) {
                    if (s->bank[i].size) {
                        sdram_bank_set_bcr(&s->bank[i], s->bank[i].bcr,
                                           s->bank[i].base, s->bank[i].size,
                                           1);
                    }
                }
                s->status &= ~0x80000000;
            } else if ((s->cfg & 0x80000000) && !(val & 0x80000000)) {
                trace_ppc4xx_sdram_enable("disable");
                /* invalidate all RAM mappings */
                for (i = 0; i < s->nbanks; i++) {
                    if (s->bank[i].size) {
                        sdram_bank_set_bcr(&s->bank[i], s->bank[i].bcr,
                                           s->bank[i].base, s->bank[i].size,
                                           0);
                    }
                }
                s->status |= 0x80000000;
            }
            if (!(s->cfg & 0x40000000) && (val & 0x40000000)) {
                s->status |= 0x40000000;
            } else if ((s->cfg & 0x40000000) && !(val & 0x40000000)) {
                s->status &= ~0x40000000;
            }
            s->cfg = val;
            break;
        case 0x24: /* SDRAM_STATUS */
            /* Read-only register */
            break;
        case 0x30: /* SDRAM_RTR */
            s->rtr = val & 0x3FF80000;
            break;
        case 0x34: /* SDRAM_PMIT */
            s->pmit = (val & 0xF8000000) | 0x07C00000;
            break;
        case 0x40: /* SDRAM_B0CR */
        case 0x44: /* SDRAM_B1CR */
        case 0x48: /* SDRAM_B2CR */
        case 0x4C: /* SDRAM_B3CR */
            i = (s->addr - 0x40) / 4;
            val &= SDRAM_DDR_BCR_MASK;
            if (s->bank[i].size) {
                sdram_bank_set_bcr(&s->bank[i], val,
                                   sdram_ddr_base(val), sdram_ddr_size(val),
                                   s->cfg & 0x80000000);
            }
            break;
        case 0x80: /* SDRAM_TR */
            s->tr = val & 0x018FC01F;
            break;
        case 0x94: /* SDRAM_ECCCFG */
            s->ecccfg = val & 0x00F00000;
            break;
        case 0x98: /* SDRAM_ECCESR */
            val &= 0xFFF0F000;
            if (s->eccesr == 0 && val != 0) {
                qemu_irq_raise(s->irq);
            } else if (s->eccesr != 0 && val == 0) {
                qemu_irq_lower(s->irq);
            }
            s->eccesr = val;
            break;
        default: /* Error */
            break;
        }
        break;
    }
}

static void ppc4xx_sdram_ddr_reset(DeviceState *dev)
{
    Ppc4xxSdramDdrState *s = PPC4xx_SDRAM_DDR(dev);

    s->addr = 0;
    s->bear = 0;
    s->besr0 = 0; /* No error */
    s->besr1 = 0; /* No error */
    s->cfg = 0;
    s->ecccfg = 0; /* No ECC */
    s->eccesr = 0; /* No error */
    s->pmit = 0x07C00000;
    s->rtr = 0x05F00000;
    s->tr = 0x00854009;
    /* We pre-initialize RAM banks */
    s->status = 0;
    s->cfg = 0x00800000;
}

static void ppc4xx_sdram_ddr_realize(DeviceState *dev, Error **errp)
{
    Ppc4xxSdramDdrState *s = PPC4xx_SDRAM_DDR(dev);
    Ppc4xxDcrDeviceState *dcr = PPC4xx_DCR_DEVICE(dev);
    const ram_addr_t valid_bank_sizes[] = {
        256 * MiB, 128 * MiB, 64 * MiB, 32 * MiB, 16 * MiB, 8 * MiB, 4 * MiB, 0
    };
    int i;

    if (s->nbanks < 1 || s->nbanks > 4) {
        error_setg(errp, "Invalid number of RAM banks");
        return;
    }
    if (!s->dram_mr) {
        error_setg(errp, "Missing dram memory region");
        return;
    }
    if (!ppc4xx_sdram_banks(s->dram_mr, s->nbanks, s->bank,
                            valid_bank_sizes, errp)) {
        return;
    }
    for (i = 0; i < s->nbanks; i++) {
        if (s->bank[i].size) {
            s->bank[i].bcr = sdram_ddr_bcr(s->bank[i].base, s->bank[i].size);
            sdram_bank_set_bcr(&s->bank[i], s->bank[i].bcr,
                               s->bank[i].base, s->bank[i].size, 0);
        } else {
            sdram_bank_set_bcr(&s->bank[i], 0, 0, 0, 0);
        }
        trace_ppc4xx_sdram_init(sdram_ddr_base(s->bank[i].bcr),
                                sdram_ddr_size(s->bank[i].bcr),
                                s->bank[i].bcr);
    }

    sysbus_init_irq(SYS_BUS_DEVICE(dev), &s->irq);

    ppc4xx_dcr_register(dcr, SDRAM0_CFGADDR,
                        s, &sdram_ddr_dcr_read, &sdram_ddr_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM0_CFGDATA,
                        s, &sdram_ddr_dcr_read, &sdram_ddr_dcr_write);
}

static Property ppc4xx_sdram_ddr_props[] = {
    DEFINE_PROP_LINK("dram", Ppc4xxSdramDdrState, dram_mr, TYPE_MEMORY_REGION,
                     MemoryRegion *),
    DEFINE_PROP_UINT32("nbanks", Ppc4xxSdramDdrState, nbanks, 4),
    DEFINE_PROP_END_OF_LIST(),
};

static void ppc4xx_sdram_ddr_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);

    dc->realize = ppc4xx_sdram_ddr_realize;
    dc->reset = ppc4xx_sdram_ddr_reset;
    /* Reason: only works as function of a ppc4xx SoC */
    dc->user_creatable = false;
    device_class_set_props(dc, ppc4xx_sdram_ddr_props);
}

void ppc4xx_sdram_ddr_enable(Ppc4xxSdramDdrState *s)
{
    sdram_ddr_dcr_write(s, SDRAM0_CFGADDR, 0x20);
    sdram_ddr_dcr_write(s, SDRAM0_CFGDATA, 0x80000000);
}

/*****************************************************************************/
/* DDR2 SDRAM controller */
#define SDRAM_DDR2_BCR_MASK 0xffe0ffc1

enum {
    SDRAM_R0BAS = 0x40,
    SDRAM_R1BAS,
    SDRAM_R2BAS,
    SDRAM_R3BAS,
    SDRAM_CONF1HB = 0x45,
    SDRAM_PLBADDULL = 0x4a,
    SDRAM_CONF1LL = 0x4b,
    SDRAM_CONFPATHB = 0x4f,
    SDRAM_PLBADDUHB = 0x50,
};

static uint32_t sdram_ddr2_bcr(hwaddr ram_base, hwaddr ram_size)
{
    uint32_t bcr;

    switch (ram_size) {
    case 8 * MiB:
        bcr = 0xffc0;
        break;
    case 16 * MiB:
        bcr = 0xff80;
        break;
    case 32 * MiB:
        bcr = 0xff00;
        break;
    case 64 * MiB:
        bcr = 0xfe00;
        break;
    case 128 * MiB:
        bcr = 0xfc00;
        break;
    case 256 * MiB:
        bcr = 0xf800;
        break;
    case 512 * MiB:
        bcr = 0xf000;
        break;
    case 1 * GiB:
        bcr = 0xe000;
        break;
    case 2 * GiB:
        bcr = 0xc000;
        break;
    case 4 * GiB:
        bcr = 0x8000;
        break;
    default:
        error_report("invalid RAM size " HWADDR_FMT_plx, ram_size);
        return 0;
    }
    bcr |= ram_base >> 2 & 0xffe00000;
    bcr |= 1;

    return bcr;
}

static inline hwaddr sdram_ddr2_base(uint32_t bcr)
{
    return (bcr & 0xffe00000) << 2;
}

static hwaddr sdram_ddr2_size(uint32_t bcr)
{
    int sh;

    sh = 1024 - ((bcr >> 6) & 0x3ff);
    return 8 * MiB * sh;
}

static uint32_t sdram_ddr2_dcr_read(void *opaque, int dcrn)
{
    Ppc4xxSdramDdr2State *s = opaque;
    uint32_t ret = 0;

    switch (dcrn) {
    case SDRAM_R0BAS:
    case SDRAM_R1BAS:
    case SDRAM_R2BAS:
    case SDRAM_R3BAS:
        if (s->bank[dcrn - SDRAM_R0BAS].size) {
            ret = sdram_ddr2_bcr(s->bank[dcrn - SDRAM_R0BAS].base,
                                 s->bank[dcrn - SDRAM_R0BAS].size);
        }
        break;
    case SDRAM_CONF1HB:
    case SDRAM_CONF1LL:
    case SDRAM_CONFPATHB:
    case SDRAM_PLBADDULL:
    case SDRAM_PLBADDUHB:
        break;
    case SDRAM0_CFGADDR:
        ret = s->addr;
        break;
    case SDRAM0_CFGDATA:
        switch (s->addr) {
        case 0x14: /* SDRAM_MCSTAT (405EX) */
        case 0x1F:
            ret = 0x80000000;
            break;
        case 0x21: /* SDRAM_MCOPT2 */
            ret = s->mcopt2;
            break;
        case 0x40: /* SDRAM_MB0CF */
            ret = 0x00008001;
            break;
        case 0x7A: /* SDRAM_DLCR */
            ret = 0x02000000;
            break;
        case 0xE1: /* SDR0_DDR0 */
            ret = SDR0_DDR0_DDRM_ENCODE(1) | SDR0_DDR0_DDRM_DDR1;
            break;
        default:
            break;
        }
        break;
    default:
        break;
    }

    return ret;
}

#define SDRAM_DDR2_MCOPT2_DCEN BIT(27)

static void sdram_ddr2_dcr_write(void *opaque, int dcrn, uint32_t val)
{
    Ppc4xxSdramDdr2State *s = opaque;
    int i;

    switch (dcrn) {
    case SDRAM_R0BAS:
    case SDRAM_R1BAS:
    case SDRAM_R2BAS:
    case SDRAM_R3BAS:
    case SDRAM_CONF1HB:
    case SDRAM_CONF1LL:
    case SDRAM_CONFPATHB:
    case SDRAM_PLBADDULL:
    case SDRAM_PLBADDUHB:
        break;
    case SDRAM0_CFGADDR:
        s->addr = val;
        break;
    case SDRAM0_CFGDATA:
        switch (s->addr) {
        case 0x00: /* B0CR */
            break;
        case 0x21: /* SDRAM_MCOPT2 */
            if (!(s->mcopt2 & SDRAM_DDR2_MCOPT2_DCEN) &&
                (val & SDRAM_DDR2_MCOPT2_DCEN)) {
                trace_ppc4xx_sdram_enable("enable");
                /* validate all RAM mappings */
                for (i = 0; i < s->nbanks; i++) {
                    if (s->bank[i].size) {
                        sdram_bank_set_bcr(&s->bank[i], s->bank[i].bcr,
                                           s->bank[i].base, s->bank[i].size,
                                           1);
                    }
                }
                s->mcopt2 |= SDRAM_DDR2_MCOPT2_DCEN;
            } else if ((s->mcopt2 & SDRAM_DDR2_MCOPT2_DCEN) &&
                       !(val & SDRAM_DDR2_MCOPT2_DCEN)) {
                trace_ppc4xx_sdram_enable("disable");
                /* invalidate all RAM mappings */
                for (i = 0; i < s->nbanks; i++) {
                    if (s->bank[i].size) {
                        sdram_bank_set_bcr(&s->bank[i], s->bank[i].bcr,
                                           s->bank[i].base, s->bank[i].size,
                                           0);
                    }
                }
                s->mcopt2 &= ~SDRAM_DDR2_MCOPT2_DCEN;
            }
            break;
        default:
            break;
        }
        break;
    default:
        break;
    }
}

static void ppc4xx_sdram_ddr2_reset(DeviceState *dev)
{
    Ppc4xxSdramDdr2State *s = PPC4xx_SDRAM_DDR2(dev);

    s->addr = 0;
    s->mcopt2 = 0;
}

static void ppc4xx_sdram_ddr2_realize(DeviceState *dev, Error **errp)
{
    Ppc4xxSdramDdr2State *s = PPC4xx_SDRAM_DDR2(dev);
    Ppc4xxDcrDeviceState *dcr = PPC4xx_DCR_DEVICE(dev);
    /*
     * SoC also has 4 GiB but that causes problem with 32 bit
     * builds (4*GiB overflows the 32 bit ram_addr_t).
     */
    const ram_addr_t valid_bank_sizes[] = {
        2 * GiB, 1 * GiB, 512 * MiB, 256 * MiB, 128 * MiB,
        64 * MiB, 32 * MiB, 16 * MiB, 8 * MiB, 0
    };
    int i;

    if (s->nbanks < 1 || s->nbanks > 4) {
        error_setg(errp, "Invalid number of RAM banks");
        return;
    }
    if (!s->dram_mr) {
        error_setg(errp, "Missing dram memory region");
        return;
    }
    if (!ppc4xx_sdram_banks(s->dram_mr, s->nbanks, s->bank,
                            valid_bank_sizes, errp)) {
        return;
    }
    for (i = 0; i < s->nbanks; i++) {
        if (s->bank[i].size) {
            s->bank[i].bcr = sdram_ddr2_bcr(s->bank[i].base, s->bank[i].size);
            s->bank[i].bcr &= SDRAM_DDR2_BCR_MASK;
            sdram_bank_set_bcr(&s->bank[i], s->bank[i].bcr,
                               s->bank[i].base, s->bank[i].size, 0);
        } else {
            sdram_bank_set_bcr(&s->bank[i], 0, 0, 0, 0);
        }
        trace_ppc4xx_sdram_init(sdram_ddr2_base(s->bank[i].bcr),
                                sdram_ddr2_size(s->bank[i].bcr),
                                s->bank[i].bcr);
    }

    ppc4xx_dcr_register(dcr, SDRAM0_CFGADDR,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM0_CFGDATA,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);

    ppc4xx_dcr_register(dcr, SDRAM_R0BAS,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_R1BAS,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_R2BAS,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_R3BAS,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_CONF1HB,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_PLBADDULL,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_CONF1LL,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_CONFPATHB,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
    ppc4xx_dcr_register(dcr, SDRAM_PLBADDUHB,
                        s, &sdram_ddr2_dcr_read, &sdram_ddr2_dcr_write);
}

static Property ppc4xx_sdram_ddr2_props[] = {
    DEFINE_PROP_LINK("dram", Ppc4xxSdramDdr2State, dram_mr, TYPE_MEMORY_REGION,
                     MemoryRegion *),
    DEFINE_PROP_UINT32("nbanks", Ppc4xxSdramDdr2State, nbanks, 4),
    DEFINE_PROP_END_OF_LIST(),
};

static void ppc4xx_sdram_ddr2_class_init(ObjectClass *oc, void *data)
{
    DeviceClass *dc = DEVICE_CLASS(oc);

    dc->realize = ppc4xx_sdram_ddr2_realize;
    dc->reset = ppc4xx_sdram_ddr2_reset;
    /* Reason: only works as function of a ppc4xx SoC */
    dc->user_creatable = false;
    device_class_set_props(dc, ppc4xx_sdram_ddr2_props);
}

void ppc4xx_sdram_ddr2_enable(Ppc4xxSdramDdr2State *s)
{
    sdram_ddr2_dcr_write(s, SDRAM0_CFGADDR, 0x21);
    sdram_ddr2_dcr_write(s, SDRAM0_CFGDATA, 0x08000000);
}

static const TypeInfo ppc4xx_sdram_types[] = {
    {
        .name           = TYPE_PPC4xx_SDRAM_DDR,
        .parent         = TYPE_PPC4xx_DCR_DEVICE,
        .instance_size  = sizeof(Ppc4xxSdramDdrState),
        .class_init     = ppc4xx_sdram_ddr_class_init,
    }, {
        .name           = TYPE_PPC4xx_SDRAM_DDR2,
        .parent         = TYPE_PPC4xx_DCR_DEVICE,
        .instance_size  = sizeof(Ppc4xxSdramDdr2State),
        .class_init     = ppc4xx_sdram_ddr2_class_init,
    }
};

DEFINE_TYPES(ppc4xx_sdram_types)