xref: /qemu/hw/misc/omap_gpmc.c (revision 29b62a10)
1 /*
2  * TI OMAP general purpose memory controller emulation.
3  *
4  * Copyright (C) 2007-2009 Nokia Corporation
5  * Original code written by Andrzej Zaborowski <andrew@openedhand.com>
6  * Enhancements for OMAP3 and NAND support written by Juha Riihimäki
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License as
10  * published by the Free Software Foundation; either version 2 or
11  * (at your option) any later version of the License.
12  *
13  * This program is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16  * GNU General Public License for more details.
17  *
18  * You should have received a copy of the GNU General Public License along
19  * with this program; if not, see <http://www.gnu.org/licenses/>.
20  */
21 
22 #include "qemu/osdep.h"
23 #include "hw/irq.h"
24 #include "hw/block/flash.h"
25 #include "hw/arm/omap.h"
26 #include "exec/memory.h"
27 #include "exec/address-spaces.h"
28 
29 /* General-Purpose Memory Controller */
30 struct omap_gpmc_s {
31     qemu_irq irq;
32     qemu_irq drq;
33     MemoryRegion iomem;
34     int accept_256;
35 
36     uint8_t revision;
37     uint8_t sysconfig;
38     uint16_t irqst;
39     uint16_t irqen;
40     uint16_t lastirq;
41     uint16_t timeout;
42     uint16_t config;
43     struct omap_gpmc_cs_file_s {
44         uint32_t config[7];
45         MemoryRegion *iomem;
46         MemoryRegion container;
47         MemoryRegion nandiomem;
48         DeviceState *dev;
49     } cs_file[8];
50     int ecc_cs;
51     int ecc_ptr;
52     uint32_t ecc_cfg;
53     ECCState ecc[9];
54     struct prefetch {
55         uint32_t config1; /* GPMC_PREFETCH_CONFIG1 */
56         uint32_t transfercount; /* GPMC_PREFETCH_CONFIG2:TRANSFERCOUNT */
57         int startengine; /* GPMC_PREFETCH_CONTROL:STARTENGINE */
58         int fifopointer; /* GPMC_PREFETCH_STATUS:FIFOPOINTER */
59         int count; /* GPMC_PREFETCH_STATUS:COUNTVALUE */
60         MemoryRegion iomem;
61         uint8_t fifo[64];
62     } prefetch;
63 };
64 
65 #define OMAP_GPMC_8BIT 0
66 #define OMAP_GPMC_16BIT 1
67 #define OMAP_GPMC_NOR 0
68 #define OMAP_GPMC_NAND 2
69 
70 static int omap_gpmc_devtype(struct omap_gpmc_cs_file_s *f)
71 {
72     return (f->config[0] >> 10) & 3;
73 }
74 
75 static int omap_gpmc_devsize(struct omap_gpmc_cs_file_s *f)
76 {
77     /* devsize field is really 2 bits but we ignore the high
78      * bit to ensure consistent behaviour if the guest sets
79      * it (values 2 and 3 are reserved in the TRM)
80      */
81     return (f->config[0] >> 12) & 1;
82 }
83 
84 /* Extract the chip-select value from the prefetch config1 register */
85 static int prefetch_cs(uint32_t config1)
86 {
87     return (config1 >> 24) & 7;
88 }
89 
90 static int prefetch_threshold(uint32_t config1)
91 {
92     return (config1 >> 8) & 0x7f;
93 }
94 
95 static void omap_gpmc_int_update(struct omap_gpmc_s *s)
96 {
97     /* The TRM is a bit unclear, but it seems to say that
98      * the TERMINALCOUNTSTATUS bit is set only on the
99      * transition when the prefetch engine goes from
100      * active to inactive, whereas the FIFOEVENTSTATUS
101      * bit is held high as long as the fifo has at
102      * least THRESHOLD bytes available.
103      * So we do the latter here, but TERMINALCOUNTSTATUS
104      * is set elsewhere.
105      */
106     if (s->prefetch.fifopointer >= prefetch_threshold(s->prefetch.config1)) {
107         s->irqst |= 1;
108     }
109     if ((s->irqen & s->irqst) != s->lastirq) {
110         s->lastirq = s->irqen & s->irqst;
111         qemu_set_irq(s->irq, s->lastirq);
112     }
113 }
114 
115 static void omap_gpmc_dma_update(struct omap_gpmc_s *s, int value)
116 {
117     if (s->prefetch.config1 & 4) {
118         qemu_set_irq(s->drq, value);
119     }
120 }
121 
122 /* Access functions for when a NAND-like device is mapped into memory:
123  * all addresses in the region behave like accesses to the relevant
124  * GPMC_NAND_DATA_i register (which is actually implemented to call these)
125  */
126 static uint64_t omap_nand_read(void *opaque, hwaddr addr,
127                                unsigned size)
128 {
129     struct omap_gpmc_cs_file_s *f = opaque;
130     uint64_t v;
131     nand_setpins(f->dev, 0, 0, 0, 1, 0);
132     switch (omap_gpmc_devsize(f)) {
133     case OMAP_GPMC_8BIT:
134         v = nand_getio(f->dev);
135         if (size == 1) {
136             return v;
137         }
138         v |= (nand_getio(f->dev) << 8);
139         if (size == 2) {
140             return v;
141         }
142         v |= (nand_getio(f->dev) << 16);
143         v |= (nand_getio(f->dev) << 24);
144         return v;
145     case OMAP_GPMC_16BIT:
146         v = nand_getio(f->dev);
147         if (size == 1) {
148             /* 8 bit read from 16 bit device : probably a guest bug */
149             return v & 0xff;
150         }
151         if (size == 2) {
152             return v;
153         }
154         v |= (nand_getio(f->dev) << 16);
155         return v;
156     default:
157         abort();
158     }
159 }
160 
161 static void omap_nand_setio(DeviceState *dev, uint64_t value,
162                             int nandsize, int size)
163 {
164     /* Write the specified value to the NAND device, respecting
165      * both size of the NAND device and size of the write access.
166      */
167     switch (nandsize) {
168     case OMAP_GPMC_8BIT:
169         switch (size) {
170         case 1:
171             nand_setio(dev, value & 0xff);
172             break;
173         case 2:
174             nand_setio(dev, value & 0xff);
175             nand_setio(dev, (value >> 8) & 0xff);
176             break;
177         case 4:
178         default:
179             nand_setio(dev, value & 0xff);
180             nand_setio(dev, (value >> 8) & 0xff);
181             nand_setio(dev, (value >> 16) & 0xff);
182             nand_setio(dev, (value >> 24) & 0xff);
183             break;
184         }
185         break;
186     case OMAP_GPMC_16BIT:
187         switch (size) {
188         case 1:
189             /* writing to a 16bit device with 8bit access is probably a guest
190              * bug; pass the value through anyway.
191              */
192         case 2:
193             nand_setio(dev, value & 0xffff);
194             break;
195         case 4:
196         default:
197             nand_setio(dev, value & 0xffff);
198             nand_setio(dev, (value >> 16) & 0xffff);
199             break;
200         }
201         break;
202     }
203 }
204 
205 static void omap_nand_write(void *opaque, hwaddr addr,
206                             uint64_t value, unsigned size)
207 {
208     struct omap_gpmc_cs_file_s *f = opaque;
209     nand_setpins(f->dev, 0, 0, 0, 1, 0);
210     omap_nand_setio(f->dev, value, omap_gpmc_devsize(f), size);
211 }
212 
213 static const MemoryRegionOps omap_nand_ops = {
214     .read = omap_nand_read,
215     .write = omap_nand_write,
216     .endianness = DEVICE_NATIVE_ENDIAN,
217 };
218 
219 static void fill_prefetch_fifo(struct omap_gpmc_s *s)
220 {
221     /* Fill the prefetch FIFO by reading data from NAND.
222      * We do this synchronously, unlike the hardware which
223      * will do this asynchronously. We refill when the
224      * FIFO has THRESHOLD bytes free, and we always refill
225      * as much data as possible starting at the top end
226      * of the FIFO.
227      * (We have to refill at THRESHOLD rather than waiting
228      * for the FIFO to empty to allow for the case where
229      * the FIFO size isn't an exact multiple of THRESHOLD
230      * and we're doing DMA transfers.)
231      * This means we never need to handle wrap-around in
232      * the fifo-reading code, and the next byte of data
233      * to read is always fifo[63 - fifopointer].
234      */
235     int fptr;
236     int cs = prefetch_cs(s->prefetch.config1);
237     int is16bit = (((s->cs_file[cs].config[0] >> 12) & 3) != 0);
238     int bytes;
239     /* Don't believe the bit of the OMAP TRM that says that COUNTVALUE
240      * and TRANSFERCOUNT are in units of 16 bit words for 16 bit NAND.
241      * Instead believe the bit that says it is always a byte count.
242      */
243     bytes = 64 - s->prefetch.fifopointer;
244     if (bytes > s->prefetch.count) {
245         bytes = s->prefetch.count;
246     }
247     if (is16bit) {
248         bytes &= ~1;
249     }
250 
251     s->prefetch.count -= bytes;
252     s->prefetch.fifopointer += bytes;
253     fptr = 64 - s->prefetch.fifopointer;
254     /* Move the existing data in the FIFO so it sits just
255      * before what we're about to read in
256      */
257     while (fptr < (64 - bytes)) {
258         s->prefetch.fifo[fptr] = s->prefetch.fifo[fptr + bytes];
259         fptr++;
260     }
261     while (fptr < 64) {
262         if (is16bit) {
263             uint32_t v = omap_nand_read(&s->cs_file[cs], 0, 2);
264             s->prefetch.fifo[fptr++] = v & 0xff;
265             s->prefetch.fifo[fptr++] = (v >> 8) & 0xff;
266         } else {
267             s->prefetch.fifo[fptr++] = omap_nand_read(&s->cs_file[cs], 0, 1);
268         }
269     }
270     if (s->prefetch.startengine && (s->prefetch.count == 0)) {
271         /* This was the final transfer: raise TERMINALCOUNTSTATUS */
272         s->irqst |= 2;
273         s->prefetch.startengine = 0;
274     }
275     /* If there are any bytes in the FIFO at this point then
276      * we must raise a DMA request (either this is a final part
277      * transfer, or we filled the FIFO in which case we certainly
278      * have THRESHOLD bytes available)
279      */
280     if (s->prefetch.fifopointer != 0) {
281         omap_gpmc_dma_update(s, 1);
282     }
283     omap_gpmc_int_update(s);
284 }
285 
286 /* Access functions for a NAND-like device when the prefetch/postwrite
287  * engine is enabled -- all addresses in the region behave alike:
288  * data is read or written to the FIFO.
289  */
290 static uint64_t omap_gpmc_prefetch_read(void *opaque, hwaddr addr,
291                                         unsigned size)
292 {
293     struct omap_gpmc_s *s = opaque;
294     uint32_t data;
295     if (s->prefetch.config1 & 1) {
296         /* The TRM doesn't define the behaviour if you read from the
297          * FIFO when the prefetch engine is in write mode. We choose
298          * to always return zero.
299          */
300         return 0;
301     }
302     /* Note that trying to read an empty fifo repeats the last byte */
303     if (s->prefetch.fifopointer) {
304         s->prefetch.fifopointer--;
305     }
306     data = s->prefetch.fifo[63 - s->prefetch.fifopointer];
307     if (s->prefetch.fifopointer ==
308         (64 - prefetch_threshold(s->prefetch.config1))) {
309         /* We've drained THRESHOLD bytes now. So deassert the
310          * DMA request, then refill the FIFO (which will probably
311          * assert it again.)
312          */
313         omap_gpmc_dma_update(s, 0);
314         fill_prefetch_fifo(s);
315     }
316     omap_gpmc_int_update(s);
317     return data;
318 }
319 
320 static void omap_gpmc_prefetch_write(void *opaque, hwaddr addr,
321                                      uint64_t value, unsigned size)
322 {
323     struct omap_gpmc_s *s = opaque;
324     int cs = prefetch_cs(s->prefetch.config1);
325     if ((s->prefetch.config1 & 1) == 0) {
326         /* The TRM doesn't define the behaviour of writing to the
327          * FIFO when the prefetch engine is in read mode. We
328          * choose to ignore the write.
329          */
330         return;
331     }
332     if (s->prefetch.count == 0) {
333         /* The TRM doesn't define the behaviour of writing to the
334          * FIFO if the transfer is complete. We choose to ignore.
335          */
336         return;
337     }
338     /* The only reason we do any data buffering in postwrite
339      * mode is if we are talking to a 16 bit NAND device, in
340      * which case we need to buffer the first byte of the
341      * 16 bit word until the other byte arrives.
342      */
343     int is16bit = (((s->cs_file[cs].config[0] >> 12) & 3) != 0);
344     if (is16bit) {
345         /* fifopointer alternates between 64 (waiting for first
346          * byte of word) and 63 (waiting for second byte)
347          */
348         if (s->prefetch.fifopointer == 64) {
349             s->prefetch.fifo[0] = value;
350             s->prefetch.fifopointer--;
351         } else {
352             value = (value << 8) | s->prefetch.fifo[0];
353             omap_nand_write(&s->cs_file[cs], 0, value, 2);
354             s->prefetch.count--;
355             s->prefetch.fifopointer = 64;
356         }
357     } else {
358         /* Just write the byte : fifopointer remains 64 at all times */
359         omap_nand_write(&s->cs_file[cs], 0, value, 1);
360         s->prefetch.count--;
361     }
362     if (s->prefetch.count == 0) {
363         /* Final transfer: raise TERMINALCOUNTSTATUS */
364         s->irqst |= 2;
365         s->prefetch.startengine = 0;
366     }
367     omap_gpmc_int_update(s);
368 }
369 
370 static const MemoryRegionOps omap_prefetch_ops = {
371     .read = omap_gpmc_prefetch_read,
372     .write = omap_gpmc_prefetch_write,
373     .endianness = DEVICE_NATIVE_ENDIAN,
374     .impl.min_access_size = 1,
375     .impl.max_access_size = 1,
376 };
377 
378 static MemoryRegion *omap_gpmc_cs_memregion(struct omap_gpmc_s *s, int cs)
379 {
380     /* Return the MemoryRegion* to map/unmap for this chipselect */
381     struct omap_gpmc_cs_file_s *f = &s->cs_file[cs];
382     if (omap_gpmc_devtype(f) == OMAP_GPMC_NOR) {
383         return f->iomem;
384     }
385     if ((s->prefetch.config1 & 0x80) &&
386         (prefetch_cs(s->prefetch.config1) == cs)) {
387         /* The prefetch engine is enabled for this CS: map the FIFO */
388         return &s->prefetch.iomem;
389     }
390     return &f->nandiomem;
391 }
392 
393 static void omap_gpmc_cs_map(struct omap_gpmc_s *s, int cs)
394 {
395     struct omap_gpmc_cs_file_s *f = &s->cs_file[cs];
396     uint32_t mask = (f->config[6] >> 8) & 0xf;
397     uint32_t base = f->config[6] & 0x3f;
398     uint32_t size;
399 
400     if (!f->iomem && !f->dev) {
401         return;
402     }
403 
404     if (!(f->config[6] & (1 << 6))) {
405         /* Do nothing unless CSVALID */
406         return;
407     }
408 
409     /* TODO: check for overlapping regions and report access errors */
410     if (mask != 0x8 && mask != 0xc && mask != 0xe && mask != 0xf
411          && !(s->accept_256 && !mask)) {
412         fprintf(stderr, "%s: invalid chip-select mask address (0x%x)\n",
413                  __func__, mask);
414     }
415 
416     base <<= 24;
417     size = (0x0fffffff & ~(mask << 24)) + 1;
418     /* TODO: rather than setting the size of the mapping (which should be
419      * constant), the mask should cause wrapping of the address space, so
420      * that the same memory becomes accessible at every <i>size</i> bytes
421      * starting from <i>base</i>.  */
422     memory_region_init(&f->container, NULL, "omap-gpmc-file", size);
423     memory_region_add_subregion(&f->container, 0,
424                                 omap_gpmc_cs_memregion(s, cs));
425     memory_region_add_subregion(get_system_memory(), base,
426                                 &f->container);
427 }
428 
429 static void omap_gpmc_cs_unmap(struct omap_gpmc_s *s, int cs)
430 {
431     struct omap_gpmc_cs_file_s *f = &s->cs_file[cs];
432     if (!(f->config[6] & (1 << 6))) {
433         /* Do nothing unless CSVALID */
434         return;
435     }
436     if (!f->iomem && !f->dev) {
437         return;
438     }
439     memory_region_del_subregion(get_system_memory(), &f->container);
440     memory_region_del_subregion(&f->container, omap_gpmc_cs_memregion(s, cs));
441     object_unparent(OBJECT(&f->container));
442 }
443 
444 void omap_gpmc_reset(struct omap_gpmc_s *s)
445 {
446     int i;
447 
448     s->sysconfig = 0;
449     s->irqst = 0;
450     s->irqen = 0;
451     omap_gpmc_int_update(s);
452     for (i = 0; i < 8; i++) {
453         /* This has to happen before we change any of the config
454          * used to determine which memory regions are mapped or unmapped.
455          */
456         omap_gpmc_cs_unmap(s, i);
457     }
458     s->timeout = 0;
459     s->config = 0xa00;
460     s->prefetch.config1 = 0x00004000;
461     s->prefetch.transfercount = 0x00000000;
462     s->prefetch.startengine = 0;
463     s->prefetch.fifopointer = 0;
464     s->prefetch.count = 0;
465     for (i = 0; i < 8; i ++) {
466         s->cs_file[i].config[1] = 0x101001;
467         s->cs_file[i].config[2] = 0x020201;
468         s->cs_file[i].config[3] = 0x10031003;
469         s->cs_file[i].config[4] = 0x10f1111;
470         s->cs_file[i].config[5] = 0;
471         s->cs_file[i].config[6] = 0xf00;
472         /* In theory we could probe attached devices for some CFG1
473          * bits here, but we just retain them across resets as they
474          * were set initially by omap_gpmc_attach().
475          */
476         if (i == 0) {
477             s->cs_file[i].config[0] &= 0x00433e00;
478             s->cs_file[i].config[6] |= 1 << 6; /* CSVALID */
479             omap_gpmc_cs_map(s, i);
480         } else {
481             s->cs_file[i].config[0] &= 0x00403c00;
482         }
483     }
484     s->ecc_cs = 0;
485     s->ecc_ptr = 0;
486     s->ecc_cfg = 0x3fcff000;
487     for (i = 0; i < 9; i ++)
488         ecc_reset(&s->ecc[i]);
489 }
490 
491 static int gpmc_wordaccess_only(hwaddr addr)
492 {
493     /* Return true if the register offset is to a register that
494      * only permits word width accesses.
495      * Non-word accesses are only OK for GPMC_NAND_DATA/ADDRESS/COMMAND
496      * for any chipselect.
497      */
498     if (addr >= 0x60 && addr <= 0x1d4) {
499         int cs = (addr - 0x60) / 0x30;
500         addr -= cs * 0x30;
501         if (addr >= 0x7c && addr < 0x88) {
502             /* GPMC_NAND_COMMAND, GPMC_NAND_ADDRESS, GPMC_NAND_DATA */
503             return 0;
504         }
505     }
506     return 1;
507 }
508 
509 static uint64_t omap_gpmc_read(void *opaque, hwaddr addr,
510                                unsigned size)
511 {
512     struct omap_gpmc_s *s = opaque;
513     int cs;
514     struct omap_gpmc_cs_file_s *f;
515 
516     if (size != 4 && gpmc_wordaccess_only(addr)) {
517         return omap_badwidth_read32(opaque, addr);
518     }
519 
520     switch (addr) {
521     case 0x000:	/* GPMC_REVISION */
522         return s->revision;
523 
524     case 0x010:	/* GPMC_SYSCONFIG */
525         return s->sysconfig;
526 
527     case 0x014:	/* GPMC_SYSSTATUS */
528         return 1;						/* RESETDONE */
529 
530     case 0x018:	/* GPMC_IRQSTATUS */
531         return s->irqst;
532 
533     case 0x01c:	/* GPMC_IRQENABLE */
534         return s->irqen;
535 
536     case 0x040:	/* GPMC_TIMEOUT_CONTROL */
537         return s->timeout;
538 
539     case 0x044:	/* GPMC_ERR_ADDRESS */
540     case 0x048:	/* GPMC_ERR_TYPE */
541         return 0;
542 
543     case 0x050:	/* GPMC_CONFIG */
544         return s->config;
545 
546     case 0x054:	/* GPMC_STATUS */
547         return 0x001;
548 
549     case 0x060 ... 0x1d4:
550         cs = (addr - 0x060) / 0x30;
551         addr -= cs * 0x30;
552         f = s->cs_file + cs;
553         switch (addr) {
554         case 0x60:      /* GPMC_CONFIG1 */
555             return f->config[0];
556         case 0x64:      /* GPMC_CONFIG2 */
557             return f->config[1];
558         case 0x68:      /* GPMC_CONFIG3 */
559             return f->config[2];
560         case 0x6c:      /* GPMC_CONFIG4 */
561             return f->config[3];
562         case 0x70:      /* GPMC_CONFIG5 */
563             return f->config[4];
564         case 0x74:      /* GPMC_CONFIG6 */
565             return f->config[5];
566         case 0x78:      /* GPMC_CONFIG7 */
567             return f->config[6];
568         case 0x84 ... 0x87: /* GPMC_NAND_DATA */
569             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
570                 return omap_nand_read(f, 0, size);
571             }
572             return 0;
573         }
574         break;
575 
576     case 0x1e0:	/* GPMC_PREFETCH_CONFIG1 */
577         return s->prefetch.config1;
578     case 0x1e4:	/* GPMC_PREFETCH_CONFIG2 */
579         return s->prefetch.transfercount;
580     case 0x1ec:	/* GPMC_PREFETCH_CONTROL */
581         return s->prefetch.startengine;
582     case 0x1f0:	/* GPMC_PREFETCH_STATUS */
583         /* NB: The OMAP3 TRM is inconsistent about whether the GPMC
584          * FIFOTHRESHOLDSTATUS bit should be set when
585          * FIFOPOINTER > FIFOTHRESHOLD or when it is >= FIFOTHRESHOLD.
586          * Apparently the underlying functional spec from which the TRM was
587          * created states that the behaviour is ">=", and this also
588          * makes more conceptual sense.
589          */
590         return (s->prefetch.fifopointer << 24) |
591                 ((s->prefetch.fifopointer >=
592                   ((s->prefetch.config1 >> 8) & 0x7f) ? 1 : 0) << 16) |
593                 s->prefetch.count;
594 
595     case 0x1f4:	/* GPMC_ECC_CONFIG */
596         return s->ecc_cs;
597     case 0x1f8:	/* GPMC_ECC_CONTROL */
598         return s->ecc_ptr;
599     case 0x1fc:	/* GPMC_ECC_SIZE_CONFIG */
600         return s->ecc_cfg;
601     case 0x200 ... 0x220:	/* GPMC_ECC_RESULT */
602         cs = (addr & 0x1f) >> 2;
603         /* TODO: check correctness */
604         return
605                 ((s->ecc[cs].cp    &  0x07) <<  0) |
606                 ((s->ecc[cs].cp    &  0x38) << 13) |
607                 ((s->ecc[cs].lp[0] & 0x1ff) <<  3) |
608                 ((s->ecc[cs].lp[1] & 0x1ff) << 19);
609 
610     case 0x230:	/* GPMC_TESTMODE_CTRL */
611         return 0;
612     case 0x234:	/* GPMC_PSA_LSB */
613     case 0x238:	/* GPMC_PSA_MSB */
614         return 0x00000000;
615     }
616 
617     OMAP_BAD_REG(addr);
618     return 0;
619 }
620 
621 static void omap_gpmc_write(void *opaque, hwaddr addr,
622                             uint64_t value, unsigned size)
623 {
624     struct omap_gpmc_s *s = opaque;
625     int cs;
626     struct omap_gpmc_cs_file_s *f;
627 
628     if (size != 4 && gpmc_wordaccess_only(addr)) {
629         omap_badwidth_write32(opaque, addr, value);
630         return;
631     }
632 
633     switch (addr) {
634     case 0x000:	/* GPMC_REVISION */
635     case 0x014:	/* GPMC_SYSSTATUS */
636     case 0x054:	/* GPMC_STATUS */
637     case 0x1f0:	/* GPMC_PREFETCH_STATUS */
638     case 0x200 ... 0x220:	/* GPMC_ECC_RESULT */
639     case 0x234:	/* GPMC_PSA_LSB */
640     case 0x238:	/* GPMC_PSA_MSB */
641         OMAP_RO_REG(addr);
642         break;
643 
644     case 0x010:	/* GPMC_SYSCONFIG */
645         if ((value >> 3) == 0x3)
646             fprintf(stderr, "%s: bad SDRAM idle mode %"PRIi64"\n",
647                             __func__, value >> 3);
648         if (value & 2)
649             omap_gpmc_reset(s);
650         s->sysconfig = value & 0x19;
651         break;
652 
653     case 0x018:	/* GPMC_IRQSTATUS */
654         s->irqst &= ~value;
655         omap_gpmc_int_update(s);
656         break;
657 
658     case 0x01c:	/* GPMC_IRQENABLE */
659         s->irqen = value & 0xf03;
660         omap_gpmc_int_update(s);
661         break;
662 
663     case 0x040:	/* GPMC_TIMEOUT_CONTROL */
664         s->timeout = value & 0x1ff1;
665         break;
666 
667     case 0x044:	/* GPMC_ERR_ADDRESS */
668     case 0x048:	/* GPMC_ERR_TYPE */
669         break;
670 
671     case 0x050:	/* GPMC_CONFIG */
672         s->config = value & 0xf13;
673         break;
674 
675     case 0x060 ... 0x1d4:
676         cs = (addr - 0x060) / 0x30;
677         addr -= cs * 0x30;
678         f = s->cs_file + cs;
679         switch (addr) {
680         case 0x60:      /* GPMC_CONFIG1 */
681             f->config[0] = value & 0xffef3e13;
682             break;
683         case 0x64:      /* GPMC_CONFIG2 */
684             f->config[1] = value & 0x001f1f8f;
685             break;
686         case 0x68:      /* GPMC_CONFIG3 */
687             f->config[2] = value & 0x001f1f8f;
688             break;
689         case 0x6c:      /* GPMC_CONFIG4 */
690             f->config[3] = value & 0x1f8f1f8f;
691             break;
692         case 0x70:      /* GPMC_CONFIG5 */
693             f->config[4] = value & 0x0f1f1f1f;
694             break;
695         case 0x74:      /* GPMC_CONFIG6 */
696             f->config[5] = value & 0x00000fcf;
697             break;
698         case 0x78:      /* GPMC_CONFIG7 */
699             if ((f->config[6] ^ value) & 0xf7f) {
700                 omap_gpmc_cs_unmap(s, cs);
701                 f->config[6] = value & 0x00000f7f;
702                 omap_gpmc_cs_map(s, cs);
703             }
704             break;
705         case 0x7c ... 0x7f: /* GPMC_NAND_COMMAND */
706             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
707                 nand_setpins(f->dev, 1, 0, 0, 1, 0); /* CLE */
708                 omap_nand_setio(f->dev, value, omap_gpmc_devsize(f), size);
709             }
710             break;
711         case 0x80 ... 0x83: /* GPMC_NAND_ADDRESS */
712             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
713                 nand_setpins(f->dev, 0, 1, 0, 1, 0); /* ALE */
714                 omap_nand_setio(f->dev, value, omap_gpmc_devsize(f), size);
715             }
716             break;
717         case 0x84 ... 0x87: /* GPMC_NAND_DATA */
718             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
719                 omap_nand_write(f, 0, value, size);
720             }
721             break;
722         default:
723             goto bad_reg;
724         }
725         break;
726 
727     case 0x1e0:	/* GPMC_PREFETCH_CONFIG1 */
728         if (!s->prefetch.startengine) {
729             uint32_t newconfig1 = value & 0x7f8f7fbf;
730             uint32_t changed;
731             changed = newconfig1 ^ s->prefetch.config1;
732             if (changed & (0x80 | 0x7000000)) {
733                 /* Turning the engine on or off, or mapping it somewhere else.
734                  * cs_map() and cs_unmap() check the prefetch config and
735                  * overall CSVALID bits, so it is sufficient to unmap-and-map
736                  * both the old cs and the new one. Note that we adhere to
737                  * the "unmap/change config/map" order (and not unmap twice
738                  * if newcs == oldcs), otherwise we'll try to delete the wrong
739                  * memory region.
740                  */
741                 int oldcs = prefetch_cs(s->prefetch.config1);
742                 int newcs = prefetch_cs(newconfig1);
743                 omap_gpmc_cs_unmap(s, oldcs);
744                 if (oldcs != newcs) {
745                     omap_gpmc_cs_unmap(s, newcs);
746                 }
747                 s->prefetch.config1 = newconfig1;
748                 omap_gpmc_cs_map(s, oldcs);
749                 if (oldcs != newcs) {
750                     omap_gpmc_cs_map(s, newcs);
751                 }
752             } else {
753                 s->prefetch.config1 = newconfig1;
754             }
755         }
756         break;
757 
758     case 0x1e4:	/* GPMC_PREFETCH_CONFIG2 */
759         if (!s->prefetch.startengine) {
760             s->prefetch.transfercount = value & 0x3fff;
761         }
762         break;
763 
764     case 0x1ec:	/* GPMC_PREFETCH_CONTROL */
765         if (s->prefetch.startengine != (value & 1)) {
766             s->prefetch.startengine = value & 1;
767             if (s->prefetch.startengine) {
768                 /* Prefetch engine start */
769                 s->prefetch.count = s->prefetch.transfercount;
770                 if (s->prefetch.config1 & 1) {
771                     /* Write */
772                     s->prefetch.fifopointer = 64;
773                 } else {
774                     /* Read */
775                     s->prefetch.fifopointer = 0;
776                     fill_prefetch_fifo(s);
777                 }
778             } else {
779                 /* Prefetch engine forcibly stopped. The TRM
780                  * doesn't define the behaviour if you do this.
781                  * We clear the prefetch count, which means that
782                  * we permit no more writes, and don't read any
783                  * more data from NAND. The CPU can still drain
784                  * the FIFO of unread data.
785                  */
786                 s->prefetch.count = 0;
787             }
788             omap_gpmc_int_update(s);
789         }
790         break;
791 
792     case 0x1f4:	/* GPMC_ECC_CONFIG */
793         s->ecc_cs = 0x8f;
794         break;
795     case 0x1f8:	/* GPMC_ECC_CONTROL */
796         if (value & (1 << 8))
797             for (cs = 0; cs < 9; cs ++)
798                 ecc_reset(&s->ecc[cs]);
799         s->ecc_ptr = value & 0xf;
800         if (s->ecc_ptr == 0 || s->ecc_ptr > 9) {
801             s->ecc_ptr = 0;
802             s->ecc_cs &= ~1;
803         }
804         break;
805     case 0x1fc:	/* GPMC_ECC_SIZE_CONFIG */
806         s->ecc_cfg = value & 0x3fcff1ff;
807         break;
808     case 0x230:	/* GPMC_TESTMODE_CTRL */
809         if (value & 7)
810             fprintf(stderr, "%s: test mode enable attempt\n", __func__);
811         break;
812 
813     default:
814     bad_reg:
815         OMAP_BAD_REG(addr);
816         return;
817     }
818 }
819 
820 static const MemoryRegionOps omap_gpmc_ops = {
821     .read = omap_gpmc_read,
822     .write = omap_gpmc_write,
823     .endianness = DEVICE_NATIVE_ENDIAN,
824 };
825 
826 struct omap_gpmc_s *omap_gpmc_init(struct omap_mpu_state_s *mpu,
827                                    hwaddr base,
828                                    qemu_irq irq, qemu_irq drq)
829 {
830     int cs;
831     struct omap_gpmc_s *s = g_new0(struct omap_gpmc_s, 1);
832 
833     memory_region_init_io(&s->iomem, NULL, &omap_gpmc_ops, s, "omap-gpmc", 0x1000);
834     memory_region_add_subregion(get_system_memory(), base, &s->iomem);
835 
836     s->irq = irq;
837     s->drq = drq;
838     s->accept_256 = cpu_is_omap3630(mpu);
839     s->revision = cpu_class_omap3(mpu) ? 0x50 : 0x20;
840     s->lastirq = 0;
841     omap_gpmc_reset(s);
842 
843     /* We have to register a different IO memory handler for each
844      * chip select region in case a NAND device is mapped there. We
845      * make the region the worst-case size of 256MB and rely on the
846      * container memory region in cs_map to chop it down to the actual
847      * guest-requested size.
848      */
849     for (cs = 0; cs < 8; cs++) {
850         memory_region_init_io(&s->cs_file[cs].nandiomem, NULL,
851                               &omap_nand_ops,
852                               &s->cs_file[cs],
853                               "omap-nand",
854                               256 * 1024 * 1024);
855     }
856 
857     memory_region_init_io(&s->prefetch.iomem, NULL, &omap_prefetch_ops, s,
858                           "omap-gpmc-prefetch", 256 * 1024 * 1024);
859     return s;
860 }
861 
862 void omap_gpmc_attach(struct omap_gpmc_s *s, int cs, MemoryRegion *iomem)
863 {
864     struct omap_gpmc_cs_file_s *f;
865     assert(iomem);
866 
867     if (cs < 0 || cs >= 8) {
868         fprintf(stderr, "%s: bad chip-select %i\n", __func__, cs);
869         exit(-1);
870     }
871     f = &s->cs_file[cs];
872 
873     omap_gpmc_cs_unmap(s, cs);
874     f->config[0] &= ~(0xf << 10);
875     f->iomem = iomem;
876     omap_gpmc_cs_map(s, cs);
877 }
878 
879 void omap_gpmc_attach_nand(struct omap_gpmc_s *s, int cs, DeviceState *nand)
880 {
881     struct omap_gpmc_cs_file_s *f;
882     assert(nand);
883 
884     if (cs < 0 || cs >= 8) {
885         fprintf(stderr, "%s: bad chip-select %i\n", __func__, cs);
886         exit(-1);
887     }
888     f = &s->cs_file[cs];
889 
890     omap_gpmc_cs_unmap(s, cs);
891     f->config[0] &= ~(0xf << 10);
892     f->config[0] |= (OMAP_GPMC_NAND << 10);
893     f->dev = nand;
894     if (nand_getbuswidth(f->dev) == 16) {
895         f->config[0] |= OMAP_GPMC_16BIT << 12;
896     }
897     omap_gpmc_cs_map(s, cs);
898 }
899