xref: /openbmc/qemu/hw/ssi/aspeed_smc.c (revision 135b03cb)
1 /*
2  * ASPEED AST2400 SMC Controller (SPI Flash Only)
3  *
4  * Copyright (C) 2016 IBM Corp.
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 
25 #include "qemu/osdep.h"
26 #include "hw/sysbus.h"
27 #include "migration/vmstate.h"
28 #include "qemu/log.h"
29 #include "qemu/module.h"
30 #include "qemu/error-report.h"
31 
32 #include "hw/irq.h"
33 #include "hw/qdev-properties.h"
34 #include "hw/ssi/aspeed_smc.h"
35 
36 /* CE Type Setting Register */
37 #define R_CONF            (0x00 / 4)
38 #define   CONF_LEGACY_DISABLE  (1 << 31)
39 #define   CONF_ENABLE_W4       20
40 #define   CONF_ENABLE_W3       19
41 #define   CONF_ENABLE_W2       18
42 #define   CONF_ENABLE_W1       17
43 #define   CONF_ENABLE_W0       16
44 #define   CONF_FLASH_TYPE4     8
45 #define   CONF_FLASH_TYPE3     6
46 #define   CONF_FLASH_TYPE2     4
47 #define   CONF_FLASH_TYPE1     2
48 #define   CONF_FLASH_TYPE0     0
49 #define      CONF_FLASH_TYPE_NOR   0x0
50 #define      CONF_FLASH_TYPE_NAND  0x1
51 #define      CONF_FLASH_TYPE_SPI   0x2
52 
53 /* CE Control Register */
54 #define R_CE_CTRL            (0x04 / 4)
55 #define   CTRL_EXTENDED4       4  /* 32 bit addressing for SPI */
56 #define   CTRL_EXTENDED3       3  /* 32 bit addressing for SPI */
57 #define   CTRL_EXTENDED2       2  /* 32 bit addressing for SPI */
58 #define   CTRL_EXTENDED1       1  /* 32 bit addressing for SPI */
59 #define   CTRL_EXTENDED0       0  /* 32 bit addressing for SPI */
60 
61 /* Interrupt Control and Status Register */
62 #define R_INTR_CTRL       (0x08 / 4)
63 #define   INTR_CTRL_DMA_STATUS            (1 << 11)
64 #define   INTR_CTRL_CMD_ABORT_STATUS      (1 << 10)
65 #define   INTR_CTRL_WRITE_PROTECT_STATUS  (1 << 9)
66 #define   INTR_CTRL_DMA_EN                (1 << 3)
67 #define   INTR_CTRL_CMD_ABORT_EN          (1 << 2)
68 #define   INTR_CTRL_WRITE_PROTECT_EN      (1 << 1)
69 
70 /* CEx Control Register */
71 #define R_CTRL0           (0x10 / 4)
72 #define   CTRL_IO_DUAL_DATA        (1 << 29)
73 #define   CTRL_IO_DUAL_ADDR_DATA   (1 << 28) /* Includes dummies */
74 #define   CTRL_CMD_SHIFT           16
75 #define   CTRL_CMD_MASK            0xff
76 #define   CTRL_DUMMY_HIGH_SHIFT    14
77 #define   CTRL_AST2400_SPI_4BYTE   (1 << 13)
78 #define   CTRL_DUMMY_LOW_SHIFT     6 /* 2 bits [7:6] */
79 #define   CTRL_CE_STOP_ACTIVE      (1 << 2)
80 #define   CTRL_CMD_MODE_MASK       0x3
81 #define     CTRL_READMODE          0x0
82 #define     CTRL_FREADMODE         0x1
83 #define     CTRL_WRITEMODE         0x2
84 #define     CTRL_USERMODE          0x3
85 #define R_CTRL1           (0x14 / 4)
86 #define R_CTRL2           (0x18 / 4)
87 #define R_CTRL3           (0x1C / 4)
88 #define R_CTRL4           (0x20 / 4)
89 
90 /* CEx Segment Address Register */
91 #define R_SEG_ADDR0       (0x30 / 4)
92 #define   SEG_END_SHIFT        24   /* 8MB units */
93 #define   SEG_END_MASK         0xff
94 #define   SEG_START_SHIFT      16   /* address bit [A29-A23] */
95 #define   SEG_START_MASK       0xff
96 #define R_SEG_ADDR1       (0x34 / 4)
97 #define R_SEG_ADDR2       (0x38 / 4)
98 #define R_SEG_ADDR3       (0x3C / 4)
99 #define R_SEG_ADDR4       (0x40 / 4)
100 
101 /* Misc Control Register #1 */
102 #define R_MISC_CTRL1      (0x50 / 4)
103 
104 /* SPI dummy cycle data */
105 #define R_DUMMY_DATA      (0x54 / 4)
106 
107 /* DMA Control/Status Register */
108 #define R_DMA_CTRL        (0x80 / 4)
109 #define   DMA_CTRL_DELAY_MASK   0xf
110 #define   DMA_CTRL_DELAY_SHIFT  8
111 #define   DMA_CTRL_FREQ_MASK    0xf
112 #define   DMA_CTRL_FREQ_SHIFT   4
113 #define   DMA_CTRL_MODE         (1 << 3)
114 #define   DMA_CTRL_CKSUM        (1 << 2)
115 #define   DMA_CTRL_DIR          (1 << 1)
116 #define   DMA_CTRL_EN           (1 << 0)
117 
118 /* DMA Flash Side Address */
119 #define R_DMA_FLASH_ADDR  (0x84 / 4)
120 
121 /* DMA DRAM Side Address */
122 #define R_DMA_DRAM_ADDR   (0x88 / 4)
123 
124 /* DMA Length Register */
125 #define R_DMA_LEN         (0x8C / 4)
126 
127 /* Checksum Calculation Result */
128 #define R_DMA_CHECKSUM    (0x90 / 4)
129 
130 /* Misc Control Register #2 */
131 #define R_TIMINGS         (0x94 / 4)
132 
133 /* SPI controller registers and bits */
134 #define R_SPI_CONF        (0x00 / 4)
135 #define   SPI_CONF_ENABLE_W0   0
136 #define R_SPI_CTRL0       (0x4 / 4)
137 #define R_SPI_MISC_CTRL   (0x10 / 4)
138 #define R_SPI_TIMINGS     (0x14 / 4)
139 
140 #define ASPEED_SMC_R_SPI_MAX (0x20 / 4)
141 #define ASPEED_SMC_R_SMC_MAX (0x20 / 4)
142 
143 #define ASPEED_SOC_SMC_FLASH_BASE   0x10000000
144 #define ASPEED_SOC_FMC_FLASH_BASE   0x20000000
145 #define ASPEED_SOC_SPI_FLASH_BASE   0x30000000
146 #define ASPEED_SOC_SPI2_FLASH_BASE  0x38000000
147 
148 /* Flash opcodes. */
149 #define SPI_OP_READ       0x03    /* Read data bytes (low frequency) */
150 
151 #define SNOOP_OFF         0xFF
152 #define SNOOP_START       0x0
153 
154 /*
155  * Default segments mapping addresses and size for each slave per
156  * controller. These can be changed when board is initialized with the
157  * Segment Address Registers.
158  */
159 static const AspeedSegments aspeed_segments_legacy[] = {
160     { 0x10000000, 32 * 1024 * 1024 },
161 };
162 
163 static const AspeedSegments aspeed_segments_fmc[] = {
164     { 0x20000000, 64 * 1024 * 1024 }, /* start address is readonly */
165     { 0x24000000, 32 * 1024 * 1024 },
166     { 0x26000000, 32 * 1024 * 1024 },
167     { 0x28000000, 32 * 1024 * 1024 },
168     { 0x2A000000, 32 * 1024 * 1024 }
169 };
170 
171 static const AspeedSegments aspeed_segments_spi[] = {
172     { 0x30000000, 64 * 1024 * 1024 },
173 };
174 
175 static const AspeedSegments aspeed_segments_ast2500_fmc[] = {
176     { 0x20000000, 128 * 1024 * 1024 }, /* start address is readonly */
177     { 0x28000000,  32 * 1024 * 1024 },
178     { 0x2A000000,  32 * 1024 * 1024 },
179 };
180 
181 static const AspeedSegments aspeed_segments_ast2500_spi1[] = {
182     { 0x30000000, 32 * 1024 * 1024 }, /* start address is readonly */
183     { 0x32000000, 96 * 1024 * 1024 }, /* end address is readonly */
184 };
185 
186 static const AspeedSegments aspeed_segments_ast2500_spi2[] = {
187     { 0x38000000, 32 * 1024 * 1024 }, /* start address is readonly */
188     { 0x3A000000, 96 * 1024 * 1024 }, /* end address is readonly */
189 };
190 
191 static const AspeedSMCController controllers[] = {
192     {
193         .name              = "aspeed.smc.smc",
194         .r_conf            = R_CONF,
195         .r_ce_ctrl         = R_CE_CTRL,
196         .r_ctrl0           = R_CTRL0,
197         .r_timings         = R_TIMINGS,
198         .conf_enable_w0    = CONF_ENABLE_W0,
199         .max_slaves        = 5,
200         .segments          = aspeed_segments_legacy,
201         .flash_window_base = ASPEED_SOC_SMC_FLASH_BASE,
202         .flash_window_size = 0x6000000,
203         .has_dma           = false,
204         .nregs             = ASPEED_SMC_R_SMC_MAX,
205     }, {
206         .name              = "aspeed.smc.fmc",
207         .r_conf            = R_CONF,
208         .r_ce_ctrl         = R_CE_CTRL,
209         .r_ctrl0           = R_CTRL0,
210         .r_timings         = R_TIMINGS,
211         .conf_enable_w0    = CONF_ENABLE_W0,
212         .max_slaves        = 5,
213         .segments          = aspeed_segments_fmc,
214         .flash_window_base = ASPEED_SOC_FMC_FLASH_BASE,
215         .flash_window_size = 0x10000000,
216         .has_dma           = true,
217         .nregs             = ASPEED_SMC_R_MAX,
218     }, {
219         .name              = "aspeed.smc.spi",
220         .r_conf            = R_SPI_CONF,
221         .r_ce_ctrl         = 0xff,
222         .r_ctrl0           = R_SPI_CTRL0,
223         .r_timings         = R_SPI_TIMINGS,
224         .conf_enable_w0    = SPI_CONF_ENABLE_W0,
225         .max_slaves        = 1,
226         .segments          = aspeed_segments_spi,
227         .flash_window_base = ASPEED_SOC_SPI_FLASH_BASE,
228         .flash_window_size = 0x10000000,
229         .has_dma           = false,
230         .nregs             = ASPEED_SMC_R_SPI_MAX,
231     }, {
232         .name              = "aspeed.smc.ast2500-fmc",
233         .r_conf            = R_CONF,
234         .r_ce_ctrl         = R_CE_CTRL,
235         .r_ctrl0           = R_CTRL0,
236         .r_timings         = R_TIMINGS,
237         .conf_enable_w0    = CONF_ENABLE_W0,
238         .max_slaves        = 3,
239         .segments          = aspeed_segments_ast2500_fmc,
240         .flash_window_base = ASPEED_SOC_FMC_FLASH_BASE,
241         .flash_window_size = 0x10000000,
242         .has_dma           = true,
243         .nregs             = ASPEED_SMC_R_MAX,
244     }, {
245         .name              = "aspeed.smc.ast2500-spi1",
246         .r_conf            = R_CONF,
247         .r_ce_ctrl         = R_CE_CTRL,
248         .r_ctrl0           = R_CTRL0,
249         .r_timings         = R_TIMINGS,
250         .conf_enable_w0    = CONF_ENABLE_W0,
251         .max_slaves        = 2,
252         .segments          = aspeed_segments_ast2500_spi1,
253         .flash_window_base = ASPEED_SOC_SPI_FLASH_BASE,
254         .flash_window_size = 0x8000000,
255         .has_dma           = false,
256         .nregs             = ASPEED_SMC_R_MAX,
257     }, {
258         .name              = "aspeed.smc.ast2500-spi2",
259         .r_conf            = R_CONF,
260         .r_ce_ctrl         = R_CE_CTRL,
261         .r_ctrl0           = R_CTRL0,
262         .r_timings         = R_TIMINGS,
263         .conf_enable_w0    = CONF_ENABLE_W0,
264         .max_slaves        = 2,
265         .segments          = aspeed_segments_ast2500_spi2,
266         .flash_window_base = ASPEED_SOC_SPI2_FLASH_BASE,
267         .flash_window_size = 0x8000000,
268         .has_dma           = false,
269         .nregs             = ASPEED_SMC_R_MAX,
270     },
271 };
272 
273 /*
274  * The Segment Register uses a 8MB unit to encode the start address
275  * and the end address of the mapping window of a flash SPI slave :
276  *
277  *        | byte 1 | byte 2 | byte 3 | byte 4 |
278  *        +--------+--------+--------+--------+
279  *        |  end   |  start |   0    |   0    |
280  *
281  */
282 static inline uint32_t aspeed_smc_segment_to_reg(const AspeedSegments *seg)
283 {
284     uint32_t reg = 0;
285     reg |= ((seg->addr >> 23) & SEG_START_MASK) << SEG_START_SHIFT;
286     reg |= (((seg->addr + seg->size) >> 23) & SEG_END_MASK) << SEG_END_SHIFT;
287     return reg;
288 }
289 
290 static inline void aspeed_smc_reg_to_segment(uint32_t reg, AspeedSegments *seg)
291 {
292     seg->addr = ((reg >> SEG_START_SHIFT) & SEG_START_MASK) << 23;
293     seg->size = (((reg >> SEG_END_SHIFT) & SEG_END_MASK) << 23) - seg->addr;
294 }
295 
296 static bool aspeed_smc_flash_overlap(const AspeedSMCState *s,
297                                      const AspeedSegments *new,
298                                      int cs)
299 {
300     AspeedSegments seg;
301     int i;
302 
303     for (i = 0; i < s->ctrl->max_slaves; i++) {
304         if (i == cs) {
305             continue;
306         }
307 
308         aspeed_smc_reg_to_segment(s->regs[R_SEG_ADDR0 + i], &seg);
309 
310         if (new->addr + new->size > seg.addr &&
311             new->addr < seg.addr + seg.size) {
312             qemu_log_mask(LOG_GUEST_ERROR, "%s: new segment CS%d [ 0x%"
313                           HWADDR_PRIx" - 0x%"HWADDR_PRIx" ] overlaps with "
314                           "CS%d [ 0x%"HWADDR_PRIx" - 0x%"HWADDR_PRIx" ]\n",
315                           s->ctrl->name, cs, new->addr, new->addr + new->size,
316                           i, seg.addr, seg.addr + seg.size);
317             return true;
318         }
319     }
320     return false;
321 }
322 
323 static void aspeed_smc_flash_set_segment(AspeedSMCState *s, int cs,
324                                          uint64_t new)
325 {
326     AspeedSMCFlash *fl = &s->flashes[cs];
327     AspeedSegments seg;
328 
329     aspeed_smc_reg_to_segment(new, &seg);
330 
331     /* The start address of CS0 is read-only */
332     if (cs == 0 && seg.addr != s->ctrl->flash_window_base) {
333         qemu_log_mask(LOG_GUEST_ERROR,
334                       "%s: Tried to change CS0 start address to 0x%"
335                       HWADDR_PRIx "\n", s->ctrl->name, seg.addr);
336         seg.addr = s->ctrl->flash_window_base;
337         new = aspeed_smc_segment_to_reg(&seg);
338     }
339 
340     /*
341      * The end address of the AST2500 spi controllers is also
342      * read-only.
343      */
344     if ((s->ctrl->segments == aspeed_segments_ast2500_spi1 ||
345          s->ctrl->segments == aspeed_segments_ast2500_spi2) &&
346         cs == s->ctrl->max_slaves &&
347         seg.addr + seg.size != s->ctrl->segments[cs].addr +
348         s->ctrl->segments[cs].size) {
349         qemu_log_mask(LOG_GUEST_ERROR,
350                       "%s: Tried to change CS%d end address to 0x%"
351                       HWADDR_PRIx "\n", s->ctrl->name, cs, seg.addr + seg.size);
352         seg.size = s->ctrl->segments[cs].addr + s->ctrl->segments[cs].size -
353             seg.addr;
354         new = aspeed_smc_segment_to_reg(&seg);
355     }
356 
357     /* Keep the segment in the overall flash window */
358     if (seg.addr + seg.size <= s->ctrl->flash_window_base ||
359         seg.addr > s->ctrl->flash_window_base + s->ctrl->flash_window_size) {
360         qemu_log_mask(LOG_GUEST_ERROR, "%s: new segment for CS%d is invalid : "
361                       "[ 0x%"HWADDR_PRIx" - 0x%"HWADDR_PRIx" ]\n",
362                       s->ctrl->name, cs, seg.addr, seg.addr + seg.size);
363         return;
364     }
365 
366     /* Check start address vs. alignment */
367     if (seg.size && !QEMU_IS_ALIGNED(seg.addr, seg.size)) {
368         qemu_log_mask(LOG_GUEST_ERROR, "%s: new segment for CS%d is not "
369                       "aligned : [ 0x%"HWADDR_PRIx" - 0x%"HWADDR_PRIx" ]\n",
370                       s->ctrl->name, cs, seg.addr, seg.addr + seg.size);
371     }
372 
373     /* And segments should not overlap (in the specs) */
374     aspeed_smc_flash_overlap(s, &seg, cs);
375 
376     /* All should be fine now to move the region */
377     memory_region_transaction_begin();
378     memory_region_set_size(&fl->mmio, seg.size);
379     memory_region_set_address(&fl->mmio, seg.addr - s->ctrl->flash_window_base);
380     memory_region_set_enabled(&fl->mmio, true);
381     memory_region_transaction_commit();
382 
383     s->regs[R_SEG_ADDR0 + cs] = new;
384 }
385 
386 static uint64_t aspeed_smc_flash_default_read(void *opaque, hwaddr addr,
387                                               unsigned size)
388 {
389     qemu_log_mask(LOG_GUEST_ERROR, "%s: To 0x%" HWADDR_PRIx " of size %u"
390                   PRIx64 "\n", __func__, addr, size);
391     return 0;
392 }
393 
394 static void aspeed_smc_flash_default_write(void *opaque, hwaddr addr,
395                                            uint64_t data, unsigned size)
396 {
397     qemu_log_mask(LOG_GUEST_ERROR, "%s: To 0x%" HWADDR_PRIx " of size %u: 0x%"
398                   PRIx64 "\n", __func__, addr, size, data);
399 }
400 
401 static const MemoryRegionOps aspeed_smc_flash_default_ops = {
402     .read = aspeed_smc_flash_default_read,
403     .write = aspeed_smc_flash_default_write,
404     .endianness = DEVICE_LITTLE_ENDIAN,
405     .valid = {
406         .min_access_size = 1,
407         .max_access_size = 4,
408     },
409 };
410 
411 static inline int aspeed_smc_flash_mode(const AspeedSMCFlash *fl)
412 {
413     const AspeedSMCState *s = fl->controller;
414 
415     return s->regs[s->r_ctrl0 + fl->id] & CTRL_CMD_MODE_MASK;
416 }
417 
418 static inline bool aspeed_smc_is_writable(const AspeedSMCFlash *fl)
419 {
420     const AspeedSMCState *s = fl->controller;
421 
422     return s->regs[s->r_conf] & (1 << (s->conf_enable_w0 + fl->id));
423 }
424 
425 static inline int aspeed_smc_flash_cmd(const AspeedSMCFlash *fl)
426 {
427     const AspeedSMCState *s = fl->controller;
428     int cmd = (s->regs[s->r_ctrl0 + fl->id] >> CTRL_CMD_SHIFT) & CTRL_CMD_MASK;
429 
430     /* In read mode, the default SPI command is READ (0x3). In other
431      * modes, the command should necessarily be defined */
432     if (aspeed_smc_flash_mode(fl) == CTRL_READMODE) {
433         cmd = SPI_OP_READ;
434     }
435 
436     if (!cmd) {
437         qemu_log_mask(LOG_GUEST_ERROR, "%s: no command defined for mode %d\n",
438                       __func__, aspeed_smc_flash_mode(fl));
439     }
440 
441     return cmd;
442 }
443 
444 static inline int aspeed_smc_flash_is_4byte(const AspeedSMCFlash *fl)
445 {
446     const AspeedSMCState *s = fl->controller;
447 
448     if (s->ctrl->segments == aspeed_segments_spi) {
449         return s->regs[s->r_ctrl0] & CTRL_AST2400_SPI_4BYTE;
450     } else {
451         return s->regs[s->r_ce_ctrl] & (1 << (CTRL_EXTENDED0 + fl->id));
452     }
453 }
454 
455 static inline bool aspeed_smc_is_ce_stop_active(const AspeedSMCFlash *fl)
456 {
457     const AspeedSMCState *s = fl->controller;
458 
459     return s->regs[s->r_ctrl0 + fl->id] & CTRL_CE_STOP_ACTIVE;
460 }
461 
462 static void aspeed_smc_flash_select(AspeedSMCFlash *fl)
463 {
464     AspeedSMCState *s = fl->controller;
465 
466     s->regs[s->r_ctrl0 + fl->id] &= ~CTRL_CE_STOP_ACTIVE;
467     qemu_set_irq(s->cs_lines[fl->id], aspeed_smc_is_ce_stop_active(fl));
468 }
469 
470 static void aspeed_smc_flash_unselect(AspeedSMCFlash *fl)
471 {
472     AspeedSMCState *s = fl->controller;
473 
474     s->regs[s->r_ctrl0 + fl->id] |= CTRL_CE_STOP_ACTIVE;
475     qemu_set_irq(s->cs_lines[fl->id], aspeed_smc_is_ce_stop_active(fl));
476 }
477 
478 static uint32_t aspeed_smc_check_segment_addr(const AspeedSMCFlash *fl,
479                                               uint32_t addr)
480 {
481     const AspeedSMCState *s = fl->controller;
482     AspeedSegments seg;
483 
484     aspeed_smc_reg_to_segment(s->regs[R_SEG_ADDR0 + fl->id], &seg);
485     if ((addr % seg.size) != addr) {
486         qemu_log_mask(LOG_GUEST_ERROR,
487                       "%s: invalid address 0x%08x for CS%d segment : "
488                       "[ 0x%"HWADDR_PRIx" - 0x%"HWADDR_PRIx" ]\n",
489                       s->ctrl->name, addr, fl->id, seg.addr,
490                       seg.addr + seg.size);
491         addr %= seg.size;
492     }
493 
494     return addr;
495 }
496 
497 static int aspeed_smc_flash_dummies(const AspeedSMCFlash *fl)
498 {
499     const AspeedSMCState *s = fl->controller;
500     uint32_t r_ctrl0 = s->regs[s->r_ctrl0 + fl->id];
501     uint32_t dummy_high = (r_ctrl0 >> CTRL_DUMMY_HIGH_SHIFT) & 0x1;
502     uint32_t dummy_low = (r_ctrl0 >> CTRL_DUMMY_LOW_SHIFT) & 0x3;
503     uint32_t dummies = ((dummy_high << 2) | dummy_low) * 8;
504 
505     if (r_ctrl0 & CTRL_IO_DUAL_ADDR_DATA) {
506         dummies /= 2;
507     }
508 
509     return dummies;
510 }
511 
512 static void aspeed_smc_flash_setup(AspeedSMCFlash *fl, uint32_t addr)
513 {
514     const AspeedSMCState *s = fl->controller;
515     uint8_t cmd = aspeed_smc_flash_cmd(fl);
516     int i;
517 
518     /* Flash access can not exceed CS segment */
519     addr = aspeed_smc_check_segment_addr(fl, addr);
520 
521     ssi_transfer(s->spi, cmd);
522 
523     if (aspeed_smc_flash_is_4byte(fl)) {
524         ssi_transfer(s->spi, (addr >> 24) & 0xff);
525     }
526     ssi_transfer(s->spi, (addr >> 16) & 0xff);
527     ssi_transfer(s->spi, (addr >> 8) & 0xff);
528     ssi_transfer(s->spi, (addr & 0xff));
529 
530     /*
531      * Use fake transfers to model dummy bytes. The value should
532      * be configured to some non-zero value in fast read mode and
533      * zero in read mode. But, as the HW allows inconsistent
534      * settings, let's check for fast read mode.
535      */
536     if (aspeed_smc_flash_mode(fl) == CTRL_FREADMODE) {
537         for (i = 0; i < aspeed_smc_flash_dummies(fl); i++) {
538             ssi_transfer(fl->controller->spi, s->regs[R_DUMMY_DATA] & 0xff);
539         }
540     }
541 }
542 
543 static uint64_t aspeed_smc_flash_read(void *opaque, hwaddr addr, unsigned size)
544 {
545     AspeedSMCFlash *fl = opaque;
546     AspeedSMCState *s = fl->controller;
547     uint64_t ret = 0;
548     int i;
549 
550     switch (aspeed_smc_flash_mode(fl)) {
551     case CTRL_USERMODE:
552         for (i = 0; i < size; i++) {
553             ret |= ssi_transfer(s->spi, 0x0) << (8 * i);
554         }
555         break;
556     case CTRL_READMODE:
557     case CTRL_FREADMODE:
558         aspeed_smc_flash_select(fl);
559         aspeed_smc_flash_setup(fl, addr);
560 
561         for (i = 0; i < size; i++) {
562             ret |= ssi_transfer(s->spi, 0x0) << (8 * i);
563         }
564 
565         aspeed_smc_flash_unselect(fl);
566         break;
567     default:
568         qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid flash mode %d\n",
569                       __func__, aspeed_smc_flash_mode(fl));
570     }
571 
572     return ret;
573 }
574 
575 /*
576  * TODO (clg@kaod.org): stolen from xilinx_spips.c. Should move to a
577  * common include header.
578  */
579 typedef enum {
580     READ = 0x3,         READ_4 = 0x13,
581     FAST_READ = 0xb,    FAST_READ_4 = 0x0c,
582     DOR = 0x3b,         DOR_4 = 0x3c,
583     QOR = 0x6b,         QOR_4 = 0x6c,
584     DIOR = 0xbb,        DIOR_4 = 0xbc,
585     QIOR = 0xeb,        QIOR_4 = 0xec,
586 
587     PP = 0x2,           PP_4 = 0x12,
588     DPP = 0xa2,
589     QPP = 0x32,         QPP_4 = 0x34,
590 } FlashCMD;
591 
592 static int aspeed_smc_num_dummies(uint8_t command)
593 {
594     switch (command) { /* check for dummies */
595     case READ: /* no dummy bytes/cycles */
596     case PP:
597     case DPP:
598     case QPP:
599     case READ_4:
600     case PP_4:
601     case QPP_4:
602         return 0;
603     case FAST_READ:
604     case DOR:
605     case QOR:
606     case DOR_4:
607     case QOR_4:
608         return 1;
609     case DIOR:
610     case FAST_READ_4:
611     case DIOR_4:
612         return 2;
613     case QIOR:
614     case QIOR_4:
615         return 4;
616     default:
617         return -1;
618     }
619 }
620 
621 static bool aspeed_smc_do_snoop(AspeedSMCFlash *fl,  uint64_t data,
622                                 unsigned size)
623 {
624     AspeedSMCState *s = fl->controller;
625     uint8_t addr_width = aspeed_smc_flash_is_4byte(fl) ? 4 : 3;
626 
627     if (s->snoop_index == SNOOP_OFF) {
628         return false; /* Do nothing */
629 
630     } else if (s->snoop_index == SNOOP_START) {
631         uint8_t cmd = data & 0xff;
632         int ndummies = aspeed_smc_num_dummies(cmd);
633 
634         /*
635          * No dummy cycles are expected with the current command. Turn
636          * off snooping and let the transfer proceed normally.
637          */
638         if (ndummies <= 0) {
639             s->snoop_index = SNOOP_OFF;
640             return false;
641         }
642 
643         s->snoop_dummies = ndummies * 8;
644 
645     } else if (s->snoop_index >= addr_width + 1) {
646 
647         /* The SPI transfer has reached the dummy cycles sequence */
648         for (; s->snoop_dummies; s->snoop_dummies--) {
649             ssi_transfer(s->spi, s->regs[R_DUMMY_DATA] & 0xff);
650         }
651 
652         /* If no more dummy cycles are expected, turn off snooping */
653         if (!s->snoop_dummies) {
654             s->snoop_index = SNOOP_OFF;
655         } else {
656             s->snoop_index += size;
657         }
658 
659         /*
660          * Dummy cycles have been faked already. Ignore the current
661          * SPI transfer
662          */
663         return true;
664     }
665 
666     s->snoop_index += size;
667     return false;
668 }
669 
670 static void aspeed_smc_flash_write(void *opaque, hwaddr addr, uint64_t data,
671                                    unsigned size)
672 {
673     AspeedSMCFlash *fl = opaque;
674     AspeedSMCState *s = fl->controller;
675     int i;
676 
677     if (!aspeed_smc_is_writable(fl)) {
678         qemu_log_mask(LOG_GUEST_ERROR, "%s: flash is not writable at 0x%"
679                       HWADDR_PRIx "\n", __func__, addr);
680         return;
681     }
682 
683     switch (aspeed_smc_flash_mode(fl)) {
684     case CTRL_USERMODE:
685         if (aspeed_smc_do_snoop(fl, data, size)) {
686             break;
687         }
688 
689         for (i = 0; i < size; i++) {
690             ssi_transfer(s->spi, (data >> (8 * i)) & 0xff);
691         }
692         break;
693     case CTRL_WRITEMODE:
694         aspeed_smc_flash_select(fl);
695         aspeed_smc_flash_setup(fl, addr);
696 
697         for (i = 0; i < size; i++) {
698             ssi_transfer(s->spi, (data >> (8 * i)) & 0xff);
699         }
700 
701         aspeed_smc_flash_unselect(fl);
702         break;
703     default:
704         qemu_log_mask(LOG_GUEST_ERROR, "%s: invalid flash mode %d\n",
705                       __func__, aspeed_smc_flash_mode(fl));
706     }
707 }
708 
709 static const MemoryRegionOps aspeed_smc_flash_ops = {
710     .read = aspeed_smc_flash_read,
711     .write = aspeed_smc_flash_write,
712     .endianness = DEVICE_LITTLE_ENDIAN,
713     .valid = {
714         .min_access_size = 1,
715         .max_access_size = 4,
716     },
717 };
718 
719 static void aspeed_smc_flash_update_cs(AspeedSMCFlash *fl)
720 {
721     AspeedSMCState *s = fl->controller;
722 
723     s->snoop_index = aspeed_smc_is_ce_stop_active(fl) ? SNOOP_OFF : SNOOP_START;
724 
725     qemu_set_irq(s->cs_lines[fl->id], aspeed_smc_is_ce_stop_active(fl));
726 }
727 
728 static void aspeed_smc_reset(DeviceState *d)
729 {
730     AspeedSMCState *s = ASPEED_SMC(d);
731     int i;
732 
733     memset(s->regs, 0, sizeof s->regs);
734 
735     /* Pretend DMA is done (u-boot initialization) */
736     s->regs[R_INTR_CTRL] = INTR_CTRL_DMA_STATUS;
737 
738     /* Unselect all slaves */
739     for (i = 0; i < s->num_cs; ++i) {
740         s->regs[s->r_ctrl0 + i] |= CTRL_CE_STOP_ACTIVE;
741         qemu_set_irq(s->cs_lines[i], true);
742     }
743 
744     /* setup default segment register values for all */
745     for (i = 0; i < s->ctrl->max_slaves; ++i) {
746         s->regs[R_SEG_ADDR0 + i] =
747             aspeed_smc_segment_to_reg(&s->ctrl->segments[i]);
748     }
749 
750     /* HW strapping flash type for FMC controllers  */
751     if (s->ctrl->segments == aspeed_segments_ast2500_fmc) {
752         /* flash type is fixed to SPI for CE0 and CE1 */
753         s->regs[s->r_conf] |= (CONF_FLASH_TYPE_SPI << CONF_FLASH_TYPE0);
754         s->regs[s->r_conf] |= (CONF_FLASH_TYPE_SPI << CONF_FLASH_TYPE1);
755     }
756 
757     /* HW strapping for AST2400 FMC controllers (SCU70). Let's use the
758      * configuration of the palmetto-bmc machine */
759     if (s->ctrl->segments == aspeed_segments_fmc) {
760         s->regs[s->r_conf] |= (CONF_FLASH_TYPE_SPI << CONF_FLASH_TYPE0);
761     }
762 
763     s->snoop_index = SNOOP_OFF;
764     s->snoop_dummies = 0;
765 }
766 
767 static uint64_t aspeed_smc_read(void *opaque, hwaddr addr, unsigned int size)
768 {
769     AspeedSMCState *s = ASPEED_SMC(opaque);
770 
771     addr >>= 2;
772 
773     if (addr == s->r_conf ||
774         addr == s->r_timings ||
775         addr == s->r_ce_ctrl ||
776         addr == R_INTR_CTRL ||
777         addr == R_DUMMY_DATA ||
778         (addr >= R_SEG_ADDR0 && addr < R_SEG_ADDR0 + s->ctrl->max_slaves) ||
779         (addr >= s->r_ctrl0 && addr < s->r_ctrl0 + s->ctrl->max_slaves)) {
780         return s->regs[addr];
781     } else {
782         qemu_log_mask(LOG_UNIMP, "%s: not implemented: 0x%" HWADDR_PRIx "\n",
783                       __func__, addr);
784         return -1;
785     }
786 }
787 
788 static void aspeed_smc_write(void *opaque, hwaddr addr, uint64_t data,
789                              unsigned int size)
790 {
791     AspeedSMCState *s = ASPEED_SMC(opaque);
792     uint32_t value = data;
793 
794     addr >>= 2;
795 
796     if (addr == s->r_conf ||
797         addr == s->r_timings ||
798         addr == s->r_ce_ctrl) {
799         s->regs[addr] = value;
800     } else if (addr >= s->r_ctrl0 && addr < s->r_ctrl0 + s->num_cs) {
801         int cs = addr - s->r_ctrl0;
802         s->regs[addr] = value;
803         aspeed_smc_flash_update_cs(&s->flashes[cs]);
804     } else if (addr >= R_SEG_ADDR0 &&
805                addr < R_SEG_ADDR0 + s->ctrl->max_slaves) {
806         int cs = addr - R_SEG_ADDR0;
807 
808         if (value != s->regs[R_SEG_ADDR0 + cs]) {
809             aspeed_smc_flash_set_segment(s, cs, value);
810         }
811     } else if (addr == R_DUMMY_DATA) {
812         s->regs[addr] = value & 0xff;
813     } else {
814         qemu_log_mask(LOG_UNIMP, "%s: not implemented: 0x%" HWADDR_PRIx "\n",
815                       __func__, addr);
816         return;
817     }
818 }
819 
820 static const MemoryRegionOps aspeed_smc_ops = {
821     .read = aspeed_smc_read,
822     .write = aspeed_smc_write,
823     .endianness = DEVICE_LITTLE_ENDIAN,
824     .valid.unaligned = true,
825 };
826 
827 static void aspeed_smc_realize(DeviceState *dev, Error **errp)
828 {
829     SysBusDevice *sbd = SYS_BUS_DEVICE(dev);
830     AspeedSMCState *s = ASPEED_SMC(dev);
831     AspeedSMCClass *mc = ASPEED_SMC_GET_CLASS(s);
832     int i;
833     char name[32];
834     hwaddr offset = 0;
835 
836     s->ctrl = mc->ctrl;
837 
838     /* keep a copy under AspeedSMCState to speed up accesses */
839     s->r_conf = s->ctrl->r_conf;
840     s->r_ce_ctrl = s->ctrl->r_ce_ctrl;
841     s->r_ctrl0 = s->ctrl->r_ctrl0;
842     s->r_timings = s->ctrl->r_timings;
843     s->conf_enable_w0 = s->ctrl->conf_enable_w0;
844 
845     /* Enforce some real HW limits */
846     if (s->num_cs > s->ctrl->max_slaves) {
847         qemu_log_mask(LOG_GUEST_ERROR, "%s: num_cs cannot exceed: %d\n",
848                       __func__, s->ctrl->max_slaves);
849         s->num_cs = s->ctrl->max_slaves;
850     }
851 
852     s->spi = ssi_create_bus(dev, "spi");
853 
854     /* Setup cs_lines for slaves */
855     sysbus_init_irq(sbd, &s->irq);
856     s->cs_lines = g_new0(qemu_irq, s->num_cs);
857     ssi_auto_connect_slaves(dev, s->cs_lines, s->spi);
858 
859     for (i = 0; i < s->num_cs; ++i) {
860         sysbus_init_irq(sbd, &s->cs_lines[i]);
861     }
862 
863     /* The memory region for the controller registers */
864     memory_region_init_io(&s->mmio, OBJECT(s), &aspeed_smc_ops, s,
865                           s->ctrl->name, s->ctrl->nregs * 4);
866     sysbus_init_mmio(sbd, &s->mmio);
867 
868     /*
869      * The container memory region representing the address space
870      * window in which the flash modules are mapped. The size and
871      * address depends on the SoC model and controller type.
872      */
873     snprintf(name, sizeof(name), "%s.flash", s->ctrl->name);
874 
875     memory_region_init_io(&s->mmio_flash, OBJECT(s),
876                           &aspeed_smc_flash_default_ops, s, name,
877                           s->ctrl->flash_window_size);
878     sysbus_init_mmio(sbd, &s->mmio_flash);
879 
880     s->flashes = g_new0(AspeedSMCFlash, s->ctrl->max_slaves);
881 
882     /*
883      * Let's create a sub memory region for each possible slave. All
884      * have a configurable memory segment in the overall flash mapping
885      * window of the controller but, there is not necessarily a flash
886      * module behind to handle the memory accesses. This depends on
887      * the board configuration.
888      */
889     for (i = 0; i < s->ctrl->max_slaves; ++i) {
890         AspeedSMCFlash *fl = &s->flashes[i];
891 
892         snprintf(name, sizeof(name), "%s.%d", s->ctrl->name, i);
893 
894         fl->id = i;
895         fl->controller = s;
896         fl->size = s->ctrl->segments[i].size;
897         memory_region_init_io(&fl->mmio, OBJECT(s), &aspeed_smc_flash_ops,
898                               fl, name, fl->size);
899         memory_region_add_subregion(&s->mmio_flash, offset, &fl->mmio);
900         offset += fl->size;
901     }
902 }
903 
904 static const VMStateDescription vmstate_aspeed_smc = {
905     .name = "aspeed.smc",
906     .version_id = 2,
907     .minimum_version_id = 2,
908     .fields = (VMStateField[]) {
909         VMSTATE_UINT32_ARRAY(regs, AspeedSMCState, ASPEED_SMC_R_MAX),
910         VMSTATE_UINT8(snoop_index, AspeedSMCState),
911         VMSTATE_UINT8(snoop_dummies, AspeedSMCState),
912         VMSTATE_END_OF_LIST()
913     }
914 };
915 
916 static Property aspeed_smc_properties[] = {
917     DEFINE_PROP_UINT32("num-cs", AspeedSMCState, num_cs, 1),
918     DEFINE_PROP_UINT64("sdram-base", AspeedSMCState, sdram_base, 0),
919     DEFINE_PROP_END_OF_LIST(),
920 };
921 
922 static void aspeed_smc_class_init(ObjectClass *klass, void *data)
923 {
924     DeviceClass *dc = DEVICE_CLASS(klass);
925     AspeedSMCClass *mc = ASPEED_SMC_CLASS(klass);
926 
927     dc->realize = aspeed_smc_realize;
928     dc->reset = aspeed_smc_reset;
929     dc->props = aspeed_smc_properties;
930     dc->vmsd = &vmstate_aspeed_smc;
931     mc->ctrl = data;
932 }
933 
934 static const TypeInfo aspeed_smc_info = {
935     .name           = TYPE_ASPEED_SMC,
936     .parent         = TYPE_SYS_BUS_DEVICE,
937     .instance_size  = sizeof(AspeedSMCState),
938     .class_size     = sizeof(AspeedSMCClass),
939     .abstract       = true,
940 };
941 
942 static void aspeed_smc_register_types(void)
943 {
944     int i;
945 
946     type_register_static(&aspeed_smc_info);
947     for (i = 0; i < ARRAY_SIZE(controllers); ++i) {
948         TypeInfo ti = {
949             .name       = controllers[i].name,
950             .parent     = TYPE_ASPEED_SMC,
951             .class_init = aspeed_smc_class_init,
952             .class_data = (void *)&controllers[i],
953         };
954         type_register(&ti);
955     }
956 }
957 
958 type_init(aspeed_smc_register_types)
959