xref: /openbmc/qemu/hw/misc/omap_gpmc.c (revision 7d405b2f)
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 #include "qemu/osdep.h"
22 #include "hw/hw.h"
23 #include "hw/block/flash.h"
24 #include "hw/arm/omap.h"
25 #include "exec/memory.h"
26 #include "exec/address-spaces.h"
27 
28 /* General-Purpose Memory Controller */
29 struct omap_gpmc_s {
30     qemu_irq irq;
31     qemu_irq drq;
32     MemoryRegion iomem;
33     int accept_256;
34 
35     uint8_t revision;
36     uint8_t sysconfig;
37     uint16_t irqst;
38     uint16_t irqen;
39     uint16_t lastirq;
40     uint16_t timeout;
41     uint16_t config;
42     struct omap_gpmc_cs_file_s {
43         uint32_t config[7];
44         MemoryRegion *iomem;
45         MemoryRegion container;
46         MemoryRegion nandiomem;
47         DeviceState *dev;
48     } cs_file[8];
49     int ecc_cs;
50     int ecc_ptr;
51     uint32_t ecc_cfg;
52     ECCState ecc[9];
53     struct prefetch {
54         uint32_t config1; /* GPMC_PREFETCH_CONFIG1 */
55         uint32_t transfercount; /* GPMC_PREFETCH_CONFIG2:TRANSFERCOUNT */
56         int startengine; /* GPMC_PREFETCH_CONTROL:STARTENGINE */
57         int fifopointer; /* GPMC_PREFETCH_STATUS:FIFOPOINTER */
58         int count; /* GPMC_PREFETCH_STATUS:COUNTVALUE */
59         MemoryRegion iomem;
60         uint8_t fifo[64];
61     } prefetch;
62 };
63 
64 #define OMAP_GPMC_8BIT 0
65 #define OMAP_GPMC_16BIT 1
66 #define OMAP_GPMC_NOR 0
67 #define OMAP_GPMC_NAND 2
68 
69 static int omap_gpmc_devtype(struct omap_gpmc_cs_file_s *f)
70 {
71     return (f->config[0] >> 10) & 3;
72 }
73 
74 static int omap_gpmc_devsize(struct omap_gpmc_cs_file_s *f)
75 {
76     /* devsize field is really 2 bits but we ignore the high
77      * bit to ensure consistent behaviour if the guest sets
78      * it (values 2 and 3 are reserved in the TRM)
79      */
80     return (f->config[0] >> 12) & 1;
81 }
82 
83 /* Extract the chip-select value from the prefetch config1 register */
84 static int prefetch_cs(uint32_t config1)
85 {
86     return (config1 >> 24) & 7;
87 }
88 
89 static int prefetch_threshold(uint32_t config1)
90 {
91     return (config1 >> 8) & 0x7f;
92 }
93 
94 static void omap_gpmc_int_update(struct omap_gpmc_s *s)
95 {
96     /* The TRM is a bit unclear, but it seems to say that
97      * the TERMINALCOUNTSTATUS bit is set only on the
98      * transition when the prefetch engine goes from
99      * active to inactive, whereas the FIFOEVENTSTATUS
100      * bit is held high as long as the fifo has at
101      * least THRESHOLD bytes available.
102      * So we do the latter here, but TERMINALCOUNTSTATUS
103      * is set elsewhere.
104      */
105     if (s->prefetch.fifopointer >= prefetch_threshold(s->prefetch.config1)) {
106         s->irqst |= 1;
107     }
108     if ((s->irqen & s->irqst) != s->lastirq) {
109         s->lastirq = s->irqen & s->irqst;
110         qemu_set_irq(s->irq, s->lastirq);
111     }
112 }
113 
114 static void omap_gpmc_dma_update(struct omap_gpmc_s *s, int value)
115 {
116     if (s->prefetch.config1 & 4) {
117         qemu_set_irq(s->drq, value);
118     }
119 }
120 
121 /* Access functions for when a NAND-like device is mapped into memory:
122  * all addresses in the region behave like accesses to the relevant
123  * GPMC_NAND_DATA_i register (which is actually implemented to call these)
124  */
125 static uint64_t omap_nand_read(void *opaque, hwaddr addr,
126                                unsigned size)
127 {
128     struct omap_gpmc_cs_file_s *f = (struct omap_gpmc_cs_file_s *)opaque;
129     uint64_t v;
130     nand_setpins(f->dev, 0, 0, 0, 1, 0);
131     switch (omap_gpmc_devsize(f)) {
132     case OMAP_GPMC_8BIT:
133         v = nand_getio(f->dev);
134         if (size == 1) {
135             return v;
136         }
137         v |= (nand_getio(f->dev) << 8);
138         if (size == 2) {
139             return v;
140         }
141         v |= (nand_getio(f->dev) << 16);
142         v |= (nand_getio(f->dev) << 24);
143         return v;
144     case OMAP_GPMC_16BIT:
145         v = nand_getio(f->dev);
146         if (size == 1) {
147             /* 8 bit read from 16 bit device : probably a guest bug */
148             return v & 0xff;
149         }
150         if (size == 2) {
151             return v;
152         }
153         v |= (nand_getio(f->dev) << 16);
154         return v;
155     default:
156         abort();
157     }
158 }
159 
160 static void omap_nand_setio(DeviceState *dev, uint64_t value,
161                             int nandsize, int size)
162 {
163     /* Write the specified value to the NAND device, respecting
164      * both size of the NAND device and size of the write access.
165      */
166     switch (nandsize) {
167     case OMAP_GPMC_8BIT:
168         switch (size) {
169         case 1:
170             nand_setio(dev, value & 0xff);
171             break;
172         case 2:
173             nand_setio(dev, value & 0xff);
174             nand_setio(dev, (value >> 8) & 0xff);
175             break;
176         case 4:
177         default:
178             nand_setio(dev, value & 0xff);
179             nand_setio(dev, (value >> 8) & 0xff);
180             nand_setio(dev, (value >> 16) & 0xff);
181             nand_setio(dev, (value >> 24) & 0xff);
182             break;
183         }
184         break;
185     case OMAP_GPMC_16BIT:
186         switch (size) {
187         case 1:
188             /* writing to a 16bit device with 8bit access is probably a guest
189              * bug; pass the value through anyway.
190              */
191         case 2:
192             nand_setio(dev, value & 0xffff);
193             break;
194         case 4:
195         default:
196             nand_setio(dev, value & 0xffff);
197             nand_setio(dev, (value >> 16) & 0xffff);
198             break;
199         }
200         break;
201     }
202 }
203 
204 static void omap_nand_write(void *opaque, hwaddr addr,
205                             uint64_t value, unsigned size)
206 {
207     struct omap_gpmc_cs_file_s *f = (struct omap_gpmc_cs_file_s *)opaque;
208     nand_setpins(f->dev, 0, 0, 0, 1, 0);
209     omap_nand_setio(f->dev, value, omap_gpmc_devsize(f), size);
210 }
211 
212 static const MemoryRegionOps omap_nand_ops = {
213     .read = omap_nand_read,
214     .write = omap_nand_write,
215     .endianness = DEVICE_NATIVE_ENDIAN,
216 };
217 
218 static void fill_prefetch_fifo(struct omap_gpmc_s *s)
219 {
220     /* Fill the prefetch FIFO by reading data from NAND.
221      * We do this synchronously, unlike the hardware which
222      * will do this asynchronously. We refill when the
223      * FIFO has THRESHOLD bytes free, and we always refill
224      * as much data as possible starting at the top end
225      * of the FIFO.
226      * (We have to refill at THRESHOLD rather than waiting
227      * for the FIFO to empty to allow for the case where
228      * the FIFO size isn't an exact multiple of THRESHOLD
229      * and we're doing DMA transfers.)
230      * This means we never need to handle wrap-around in
231      * the fifo-reading code, and the next byte of data
232      * to read is always fifo[63 - fifopointer].
233      */
234     int fptr;
235     int cs = prefetch_cs(s->prefetch.config1);
236     int is16bit = (((s->cs_file[cs].config[0] >> 12) & 3) != 0);
237     int bytes;
238     /* Don't believe the bit of the OMAP TRM that says that COUNTVALUE
239      * and TRANSFERCOUNT are in units of 16 bit words for 16 bit NAND.
240      * Instead believe the bit that says it is always a byte count.
241      */
242     bytes = 64 - s->prefetch.fifopointer;
243     if (bytes > s->prefetch.count) {
244         bytes = s->prefetch.count;
245     }
246     if (is16bit) {
247         bytes &= ~1;
248     }
249 
250     s->prefetch.count -= bytes;
251     s->prefetch.fifopointer += bytes;
252     fptr = 64 - s->prefetch.fifopointer;
253     /* Move the existing data in the FIFO so it sits just
254      * before what we're about to read in
255      */
256     while (fptr < (64 - bytes)) {
257         s->prefetch.fifo[fptr] = s->prefetch.fifo[fptr + bytes];
258         fptr++;
259     }
260     while (fptr < 64) {
261         if (is16bit) {
262             uint32_t v = omap_nand_read(&s->cs_file[cs], 0, 2);
263             s->prefetch.fifo[fptr++] = v & 0xff;
264             s->prefetch.fifo[fptr++] = (v >> 8) & 0xff;
265         } else {
266             s->prefetch.fifo[fptr++] = omap_nand_read(&s->cs_file[cs], 0, 1);
267         }
268     }
269     if (s->prefetch.startengine && (s->prefetch.count == 0)) {
270         /* This was the final transfer: raise TERMINALCOUNTSTATUS */
271         s->irqst |= 2;
272         s->prefetch.startengine = 0;
273     }
274     /* If there are any bytes in the FIFO at this point then
275      * we must raise a DMA request (either this is a final part
276      * transfer, or we filled the FIFO in which case we certainly
277      * have THRESHOLD bytes available)
278      */
279     if (s->prefetch.fifopointer != 0) {
280         omap_gpmc_dma_update(s, 1);
281     }
282     omap_gpmc_int_update(s);
283 }
284 
285 /* Access functions for a NAND-like device when the prefetch/postwrite
286  * engine is enabled -- all addresses in the region behave alike:
287  * data is read or written to the FIFO.
288  */
289 static uint64_t omap_gpmc_prefetch_read(void *opaque, hwaddr addr,
290                                         unsigned size)
291 {
292     struct omap_gpmc_s *s = (struct omap_gpmc_s *) opaque;
293     uint32_t data;
294     if (s->prefetch.config1 & 1) {
295         /* The TRM doesn't define the behaviour if you read from the
296          * FIFO when the prefetch engine is in write mode. We choose
297          * to always return zero.
298          */
299         return 0;
300     }
301     /* Note that trying to read an empty fifo repeats the last byte */
302     if (s->prefetch.fifopointer) {
303         s->prefetch.fifopointer--;
304     }
305     data = s->prefetch.fifo[63 - s->prefetch.fifopointer];
306     if (s->prefetch.fifopointer ==
307         (64 - prefetch_threshold(s->prefetch.config1))) {
308         /* We've drained THRESHOLD bytes now. So deassert the
309          * DMA request, then refill the FIFO (which will probably
310          * assert it again.)
311          */
312         omap_gpmc_dma_update(s, 0);
313         fill_prefetch_fifo(s);
314     }
315     omap_gpmc_int_update(s);
316     return data;
317 }
318 
319 static void omap_gpmc_prefetch_write(void *opaque, hwaddr addr,
320                                      uint64_t value, unsigned size)
321 {
322     struct omap_gpmc_s *s = (struct omap_gpmc_s *) opaque;
323     int cs = prefetch_cs(s->prefetch.config1);
324     if ((s->prefetch.config1 & 1) == 0) {
325         /* The TRM doesn't define the behaviour of writing to the
326          * FIFO when the prefetch engine is in read mode. We
327          * choose to ignore the write.
328          */
329         return;
330     }
331     if (s->prefetch.count == 0) {
332         /* The TRM doesn't define the behaviour of writing to the
333          * FIFO if the transfer is complete. We choose to ignore.
334          */
335         return;
336     }
337     /* The only reason we do any data buffering in postwrite
338      * mode is if we are talking to a 16 bit NAND device, in
339      * which case we need to buffer the first byte of the
340      * 16 bit word until the other byte arrives.
341      */
342     int is16bit = (((s->cs_file[cs].config[0] >> 12) & 3) != 0);
343     if (is16bit) {
344         /* fifopointer alternates between 64 (waiting for first
345          * byte of word) and 63 (waiting for second byte)
346          */
347         if (s->prefetch.fifopointer == 64) {
348             s->prefetch.fifo[0] = value;
349             s->prefetch.fifopointer--;
350         } else {
351             value = (value << 8) | s->prefetch.fifo[0];
352             omap_nand_write(&s->cs_file[cs], 0, value, 2);
353             s->prefetch.count--;
354             s->prefetch.fifopointer = 64;
355         }
356     } else {
357         /* Just write the byte : fifopointer remains 64 at all times */
358         omap_nand_write(&s->cs_file[cs], 0, value, 1);
359         s->prefetch.count--;
360     }
361     if (s->prefetch.count == 0) {
362         /* Final transfer: raise TERMINALCOUNTSTATUS */
363         s->irqst |= 2;
364         s->prefetch.startengine = 0;
365     }
366     omap_gpmc_int_update(s);
367 }
368 
369 static const MemoryRegionOps omap_prefetch_ops = {
370     .read = omap_gpmc_prefetch_read,
371     .write = omap_gpmc_prefetch_write,
372     .endianness = DEVICE_NATIVE_ENDIAN,
373     .impl.min_access_size = 1,
374     .impl.max_access_size = 1,
375 };
376 
377 static MemoryRegion *omap_gpmc_cs_memregion(struct omap_gpmc_s *s, int cs)
378 {
379     /* Return the MemoryRegion* to map/unmap for this chipselect */
380     struct omap_gpmc_cs_file_s *f = &s->cs_file[cs];
381     if (omap_gpmc_devtype(f) == OMAP_GPMC_NOR) {
382         return f->iomem;
383     }
384     if ((s->prefetch.config1 & 0x80) &&
385         (prefetch_cs(s->prefetch.config1) == cs)) {
386         /* The prefetch engine is enabled for this CS: map the FIFO */
387         return &s->prefetch.iomem;
388     }
389     return &f->nandiomem;
390 }
391 
392 static void omap_gpmc_cs_map(struct omap_gpmc_s *s, int cs)
393 {
394     struct omap_gpmc_cs_file_s *f = &s->cs_file[cs];
395     uint32_t mask = (f->config[6] >> 8) & 0xf;
396     uint32_t base = f->config[6] & 0x3f;
397     uint32_t size;
398 
399     if (!f->iomem && !f->dev) {
400         return;
401     }
402 
403     if (!(f->config[6] & (1 << 6))) {
404         /* Do nothing unless CSVALID */
405         return;
406     }
407 
408     /* TODO: check for overlapping regions and report access errors */
409     if (mask != 0x8 && mask != 0xc && mask != 0xe && mask != 0xf
410          && !(s->accept_256 && !mask)) {
411         fprintf(stderr, "%s: invalid chip-select mask address (0x%x)\n",
412                  __func__, mask);
413     }
414 
415     base <<= 24;
416     size = (0x0fffffff & ~(mask << 24)) + 1;
417     /* TODO: rather than setting the size of the mapping (which should be
418      * constant), the mask should cause wrapping of the address space, so
419      * that the same memory becomes accessible at every <i>size</i> bytes
420      * starting from <i>base</i>.  */
421     memory_region_init(&f->container, NULL, "omap-gpmc-file", size);
422     memory_region_add_subregion(&f->container, 0,
423                                 omap_gpmc_cs_memregion(s, cs));
424     memory_region_add_subregion(get_system_memory(), base,
425                                 &f->container);
426 }
427 
428 static void omap_gpmc_cs_unmap(struct omap_gpmc_s *s, int cs)
429 {
430     struct omap_gpmc_cs_file_s *f = &s->cs_file[cs];
431     if (!(f->config[6] & (1 << 6))) {
432         /* Do nothing unless CSVALID */
433         return;
434     }
435     if (!f->iomem && !f->dev) {
436         return;
437     }
438     memory_region_del_subregion(get_system_memory(), &f->container);
439     memory_region_del_subregion(&f->container, omap_gpmc_cs_memregion(s, cs));
440     object_unparent(OBJECT(&f->container));
441 }
442 
443 void omap_gpmc_reset(struct omap_gpmc_s *s)
444 {
445     int i;
446 
447     s->sysconfig = 0;
448     s->irqst = 0;
449     s->irqen = 0;
450     omap_gpmc_int_update(s);
451     for (i = 0; i < 8; i++) {
452         /* This has to happen before we change any of the config
453          * used to determine which memory regions are mapped or unmapped.
454          */
455         omap_gpmc_cs_unmap(s, i);
456     }
457     s->timeout = 0;
458     s->config = 0xa00;
459     s->prefetch.config1 = 0x00004000;
460     s->prefetch.transfercount = 0x00000000;
461     s->prefetch.startengine = 0;
462     s->prefetch.fifopointer = 0;
463     s->prefetch.count = 0;
464     for (i = 0; i < 8; i ++) {
465         s->cs_file[i].config[1] = 0x101001;
466         s->cs_file[i].config[2] = 0x020201;
467         s->cs_file[i].config[3] = 0x10031003;
468         s->cs_file[i].config[4] = 0x10f1111;
469         s->cs_file[i].config[5] = 0;
470         s->cs_file[i].config[6] = 0xf00;
471         /* In theory we could probe attached devices for some CFG1
472          * bits here, but we just retain them across resets as they
473          * were set initially by omap_gpmc_attach().
474          */
475         if (i == 0) {
476             s->cs_file[i].config[0] &= 0x00433e00;
477             s->cs_file[i].config[6] |= 1 << 6; /* CSVALID */
478             omap_gpmc_cs_map(s, i);
479         } else {
480             s->cs_file[i].config[0] &= 0x00403c00;
481         }
482     }
483     s->ecc_cs = 0;
484     s->ecc_ptr = 0;
485     s->ecc_cfg = 0x3fcff000;
486     for (i = 0; i < 9; i ++)
487         ecc_reset(&s->ecc[i]);
488 }
489 
490 static int gpmc_wordaccess_only(hwaddr addr)
491 {
492     /* Return true if the register offset is to a register that
493      * only permits word width accesses.
494      * Non-word accesses are only OK for GPMC_NAND_DATA/ADDRESS/COMMAND
495      * for any chipselect.
496      */
497     if (addr >= 0x60 && addr <= 0x1d4) {
498         int cs = (addr - 0x60) / 0x30;
499         addr -= cs * 0x30;
500         if (addr >= 0x7c && addr < 0x88) {
501             /* GPMC_NAND_COMMAND, GPMC_NAND_ADDRESS, GPMC_NAND_DATA */
502             return 0;
503         }
504     }
505     return 1;
506 }
507 
508 static uint64_t omap_gpmc_read(void *opaque, hwaddr addr,
509                                unsigned size)
510 {
511     struct omap_gpmc_s *s = (struct omap_gpmc_s *) opaque;
512     int cs;
513     struct omap_gpmc_cs_file_s *f;
514 
515     if (size != 4 && gpmc_wordaccess_only(addr)) {
516         return omap_badwidth_read32(opaque, addr);
517     }
518 
519     switch (addr) {
520     case 0x000:	/* GPMC_REVISION */
521         return s->revision;
522 
523     case 0x010:	/* GPMC_SYSCONFIG */
524         return s->sysconfig;
525 
526     case 0x014:	/* GPMC_SYSSTATUS */
527         return 1;						/* RESETDONE */
528 
529     case 0x018:	/* GPMC_IRQSTATUS */
530         return s->irqst;
531 
532     case 0x01c:	/* GPMC_IRQENABLE */
533         return s->irqen;
534 
535     case 0x040:	/* GPMC_TIMEOUT_CONTROL */
536         return s->timeout;
537 
538     case 0x044:	/* GPMC_ERR_ADDRESS */
539     case 0x048:	/* GPMC_ERR_TYPE */
540         return 0;
541 
542     case 0x050:	/* GPMC_CONFIG */
543         return s->config;
544 
545     case 0x054:	/* GPMC_STATUS */
546         return 0x001;
547 
548     case 0x060 ... 0x1d4:
549         cs = (addr - 0x060) / 0x30;
550         addr -= cs * 0x30;
551         f = s->cs_file + cs;
552         switch (addr) {
553         case 0x60:      /* GPMC_CONFIG1 */
554             return f->config[0];
555         case 0x64:      /* GPMC_CONFIG2 */
556             return f->config[1];
557         case 0x68:      /* GPMC_CONFIG3 */
558             return f->config[2];
559         case 0x6c:      /* GPMC_CONFIG4 */
560             return f->config[3];
561         case 0x70:      /* GPMC_CONFIG5 */
562             return f->config[4];
563         case 0x74:      /* GPMC_CONFIG6 */
564             return f->config[5];
565         case 0x78:      /* GPMC_CONFIG7 */
566             return f->config[6];
567         case 0x84 ... 0x87: /* GPMC_NAND_DATA */
568             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
569                 return omap_nand_read(f, 0, size);
570             }
571             return 0;
572         }
573         break;
574 
575     case 0x1e0:	/* GPMC_PREFETCH_CONFIG1 */
576         return s->prefetch.config1;
577     case 0x1e4:	/* GPMC_PREFETCH_CONFIG2 */
578         return s->prefetch.transfercount;
579     case 0x1ec:	/* GPMC_PREFETCH_CONTROL */
580         return s->prefetch.startengine;
581     case 0x1f0:	/* GPMC_PREFETCH_STATUS */
582         /* NB: The OMAP3 TRM is inconsistent about whether the GPMC
583          * FIFOTHRESHOLDSTATUS bit should be set when
584          * FIFOPOINTER > FIFOTHRESHOLD or when it is >= FIFOTHRESHOLD.
585          * Apparently the underlying functional spec from which the TRM was
586          * created states that the behaviour is ">=", and this also
587          * makes more conceptual sense.
588          */
589         return (s->prefetch.fifopointer << 24) |
590                 ((s->prefetch.fifopointer >=
591                   ((s->prefetch.config1 >> 8) & 0x7f) ? 1 : 0) << 16) |
592                 s->prefetch.count;
593 
594     case 0x1f4:	/* GPMC_ECC_CONFIG */
595         return s->ecc_cs;
596     case 0x1f8:	/* GPMC_ECC_CONTROL */
597         return s->ecc_ptr;
598     case 0x1fc:	/* GPMC_ECC_SIZE_CONFIG */
599         return s->ecc_cfg;
600     case 0x200 ... 0x220:	/* GPMC_ECC_RESULT */
601         cs = (addr & 0x1f) >> 2;
602         /* TODO: check correctness */
603         return
604                 ((s->ecc[cs].cp    &  0x07) <<  0) |
605                 ((s->ecc[cs].cp    &  0x38) << 13) |
606                 ((s->ecc[cs].lp[0] & 0x1ff) <<  3) |
607                 ((s->ecc[cs].lp[1] & 0x1ff) << 19);
608 
609     case 0x230:	/* GPMC_TESTMODE_CTRL */
610         return 0;
611     case 0x234:	/* GPMC_PSA_LSB */
612     case 0x238:	/* GPMC_PSA_MSB */
613         return 0x00000000;
614     }
615 
616     OMAP_BAD_REG(addr);
617     return 0;
618 }
619 
620 static void omap_gpmc_write(void *opaque, hwaddr addr,
621                             uint64_t value, unsigned size)
622 {
623     struct omap_gpmc_s *s = (struct omap_gpmc_s *) opaque;
624     int cs;
625     struct omap_gpmc_cs_file_s *f;
626 
627     if (size != 4 && gpmc_wordaccess_only(addr)) {
628         omap_badwidth_write32(opaque, addr, value);
629         return;
630     }
631 
632     switch (addr) {
633     case 0x000:	/* GPMC_REVISION */
634     case 0x014:	/* GPMC_SYSSTATUS */
635     case 0x054:	/* GPMC_STATUS */
636     case 0x1f0:	/* GPMC_PREFETCH_STATUS */
637     case 0x200 ... 0x220:	/* GPMC_ECC_RESULT */
638     case 0x234:	/* GPMC_PSA_LSB */
639     case 0x238:	/* GPMC_PSA_MSB */
640         OMAP_RO_REG(addr);
641         break;
642 
643     case 0x010:	/* GPMC_SYSCONFIG */
644         if ((value >> 3) == 0x3)
645             fprintf(stderr, "%s: bad SDRAM idle mode %"PRIi64"\n",
646                             __func__, value >> 3);
647         if (value & 2)
648             omap_gpmc_reset(s);
649         s->sysconfig = value & 0x19;
650         break;
651 
652     case 0x018:	/* GPMC_IRQSTATUS */
653         s->irqst &= ~value;
654         omap_gpmc_int_update(s);
655         break;
656 
657     case 0x01c:	/* GPMC_IRQENABLE */
658         s->irqen = value & 0xf03;
659         omap_gpmc_int_update(s);
660         break;
661 
662     case 0x040:	/* GPMC_TIMEOUT_CONTROL */
663         s->timeout = value & 0x1ff1;
664         break;
665 
666     case 0x044:	/* GPMC_ERR_ADDRESS */
667     case 0x048:	/* GPMC_ERR_TYPE */
668         break;
669 
670     case 0x050:	/* GPMC_CONFIG */
671         s->config = value & 0xf13;
672         break;
673 
674     case 0x060 ... 0x1d4:
675         cs = (addr - 0x060) / 0x30;
676         addr -= cs * 0x30;
677         f = s->cs_file + cs;
678         switch (addr) {
679         case 0x60:      /* GPMC_CONFIG1 */
680             f->config[0] = value & 0xffef3e13;
681             break;
682         case 0x64:      /* GPMC_CONFIG2 */
683             f->config[1] = value & 0x001f1f8f;
684             break;
685         case 0x68:      /* GPMC_CONFIG3 */
686             f->config[2] = value & 0x001f1f8f;
687             break;
688         case 0x6c:      /* GPMC_CONFIG4 */
689             f->config[3] = value & 0x1f8f1f8f;
690             break;
691         case 0x70:      /* GPMC_CONFIG5 */
692             f->config[4] = value & 0x0f1f1f1f;
693             break;
694         case 0x74:      /* GPMC_CONFIG6 */
695             f->config[5] = value & 0x00000fcf;
696             break;
697         case 0x78:      /* GPMC_CONFIG7 */
698             if ((f->config[6] ^ value) & 0xf7f) {
699                 omap_gpmc_cs_unmap(s, cs);
700                 f->config[6] = value & 0x00000f7f;
701                 omap_gpmc_cs_map(s, cs);
702             }
703             break;
704         case 0x7c ... 0x7f: /* GPMC_NAND_COMMAND */
705             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
706                 nand_setpins(f->dev, 1, 0, 0, 1, 0); /* CLE */
707                 omap_nand_setio(f->dev, value, omap_gpmc_devsize(f), size);
708             }
709             break;
710         case 0x80 ... 0x83: /* GPMC_NAND_ADDRESS */
711             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
712                 nand_setpins(f->dev, 0, 1, 0, 1, 0); /* ALE */
713                 omap_nand_setio(f->dev, value, omap_gpmc_devsize(f), size);
714             }
715             break;
716         case 0x84 ... 0x87: /* GPMC_NAND_DATA */
717             if (omap_gpmc_devtype(f) == OMAP_GPMC_NAND) {
718                 omap_nand_write(f, 0, value, size);
719             }
720             break;
721         default:
722             goto bad_reg;
723         }
724         break;
725 
726     case 0x1e0:	/* GPMC_PREFETCH_CONFIG1 */
727         if (!s->prefetch.startengine) {
728             uint32_t newconfig1 = value & 0x7f8f7fbf;
729             uint32_t changed;
730             changed = newconfig1 ^ s->prefetch.config1;
731             if (changed & (0x80 | 0x7000000)) {
732                 /* Turning the engine on or off, or mapping it somewhere else.
733                  * cs_map() and cs_unmap() check the prefetch config and
734                  * overall CSVALID bits, so it is sufficient to unmap-and-map
735                  * both the old cs and the new one. Note that we adhere to
736                  * the "unmap/change config/map" order (and not unmap twice
737                  * if newcs == oldcs), otherwise we'll try to delete the wrong
738                  * memory region.
739                  */
740                 int oldcs = prefetch_cs(s->prefetch.config1);
741                 int newcs = prefetch_cs(newconfig1);
742                 omap_gpmc_cs_unmap(s, oldcs);
743                 if (oldcs != newcs) {
744                     omap_gpmc_cs_unmap(s, newcs);
745                 }
746                 s->prefetch.config1 = newconfig1;
747                 omap_gpmc_cs_map(s, oldcs);
748                 if (oldcs != newcs) {
749                     omap_gpmc_cs_map(s, newcs);
750                 }
751             } else {
752                 s->prefetch.config1 = newconfig1;
753             }
754         }
755         break;
756 
757     case 0x1e4:	/* GPMC_PREFETCH_CONFIG2 */
758         if (!s->prefetch.startengine) {
759             s->prefetch.transfercount = value & 0x3fff;
760         }
761         break;
762 
763     case 0x1ec:	/* GPMC_PREFETCH_CONTROL */
764         if (s->prefetch.startengine != (value & 1)) {
765             s->prefetch.startengine = value & 1;
766             if (s->prefetch.startengine) {
767                 /* Prefetch engine start */
768                 s->prefetch.count = s->prefetch.transfercount;
769                 if (s->prefetch.config1 & 1) {
770                     /* Write */
771                     s->prefetch.fifopointer = 64;
772                 } else {
773                     /* Read */
774                     s->prefetch.fifopointer = 0;
775                     fill_prefetch_fifo(s);
776                 }
777             } else {
778                 /* Prefetch engine forcibly stopped. The TRM
779                  * doesn't define the behaviour if you do this.
780                  * We clear the prefetch count, which means that
781                  * we permit no more writes, and don't read any
782                  * more data from NAND. The CPU can still drain
783                  * the FIFO of unread data.
784                  */
785                 s->prefetch.count = 0;
786             }
787             omap_gpmc_int_update(s);
788         }
789         break;
790 
791     case 0x1f4:	/* GPMC_ECC_CONFIG */
792         s->ecc_cs = 0x8f;
793         break;
794     case 0x1f8:	/* GPMC_ECC_CONTROL */
795         if (value & (1 << 8))
796             for (cs = 0; cs < 9; cs ++)
797                 ecc_reset(&s->ecc[cs]);
798         s->ecc_ptr = value & 0xf;
799         if (s->ecc_ptr == 0 || s->ecc_ptr > 9) {
800             s->ecc_ptr = 0;
801             s->ecc_cs &= ~1;
802         }
803         break;
804     case 0x1fc:	/* GPMC_ECC_SIZE_CONFIG */
805         s->ecc_cfg = value & 0x3fcff1ff;
806         break;
807     case 0x230:	/* GPMC_TESTMODE_CTRL */
808         if (value & 7)
809             fprintf(stderr, "%s: test mode enable attempt\n", __func__);
810         break;
811 
812     default:
813     bad_reg:
814         OMAP_BAD_REG(addr);
815         return;
816     }
817 }
818 
819 static const MemoryRegionOps omap_gpmc_ops = {
820     .read = omap_gpmc_read,
821     .write = omap_gpmc_write,
822     .endianness = DEVICE_NATIVE_ENDIAN,
823 };
824 
825 struct omap_gpmc_s *omap_gpmc_init(struct omap_mpu_state_s *mpu,
826                                    hwaddr base,
827                                    qemu_irq irq, qemu_irq drq)
828 {
829     int cs;
830     struct omap_gpmc_s *s = g_new0(struct omap_gpmc_s, 1);
831 
832     memory_region_init_io(&s->iomem, NULL, &omap_gpmc_ops, s, "omap-gpmc", 0x1000);
833     memory_region_add_subregion(get_system_memory(), base, &s->iomem);
834 
835     s->irq = irq;
836     s->drq = drq;
837     s->accept_256 = cpu_is_omap3630(mpu);
838     s->revision = cpu_class_omap3(mpu) ? 0x50 : 0x20;
839     s->lastirq = 0;
840     omap_gpmc_reset(s);
841 
842     /* We have to register a different IO memory handler for each
843      * chip select region in case a NAND device is mapped there. We
844      * make the region the worst-case size of 256MB and rely on the
845      * container memory region in cs_map to chop it down to the actual
846      * guest-requested size.
847      */
848     for (cs = 0; cs < 8; cs++) {
849         memory_region_init_io(&s->cs_file[cs].nandiomem, NULL,
850                               &omap_nand_ops,
851                               &s->cs_file[cs],
852                               "omap-nand",
853                               256 * 1024 * 1024);
854     }
855 
856     memory_region_init_io(&s->prefetch.iomem, NULL, &omap_prefetch_ops, s,
857                           "omap-gpmc-prefetch", 256 * 1024 * 1024);
858     return s;
859 }
860 
861 void omap_gpmc_attach(struct omap_gpmc_s *s, int cs, MemoryRegion *iomem)
862 {
863     struct omap_gpmc_cs_file_s *f;
864     assert(iomem);
865 
866     if (cs < 0 || cs >= 8) {
867         fprintf(stderr, "%s: bad chip-select %i\n", __func__, cs);
868         exit(-1);
869     }
870     f = &s->cs_file[cs];
871 
872     omap_gpmc_cs_unmap(s, cs);
873     f->config[0] &= ~(0xf << 10);
874     f->iomem = iomem;
875     omap_gpmc_cs_map(s, cs);
876 }
877 
878 void omap_gpmc_attach_nand(struct omap_gpmc_s *s, int cs, DeviceState *nand)
879 {
880     struct omap_gpmc_cs_file_s *f;
881     assert(nand);
882 
883     if (cs < 0 || cs >= 8) {
884         fprintf(stderr, "%s: bad chip-select %i\n", __func__, cs);
885         exit(-1);
886     }
887     f = &s->cs_file[cs];
888 
889     omap_gpmc_cs_unmap(s, cs);
890     f->config[0] &= ~(0xf << 10);
891     f->config[0] |= (OMAP_GPMC_NAND << 10);
892     f->dev = nand;
893     if (nand_getbuswidth(f->dev) == 16) {
894         f->config[0] |= OMAP_GPMC_16BIT << 12;
895     }
896     omap_gpmc_cs_map(s, cs);
897 }
898