xref: /openbmc/qemu/hw/sd/bcm2835_sdhost.c (revision 39164c13)
1 /*
2  * Raspberry Pi (BCM2835) SD Host Controller
3  *
4  * Copyright (c) 2017 Antfield SAS
5  *
6  * Authors:
7  *  Clement Deschamps <clement.deschamps@antfield.fr>
8  *  Luc Michel <luc.michel@antfield.fr>
9  *
10  * This work is licensed under the terms of the GNU GPL, version 2 or later.
11  * See the COPYING file in the top-level directory.
12  */
13 
14 #include "qemu/osdep.h"
15 #include "qemu/log.h"
16 #include "sysemu/blockdev.h"
17 #include "hw/sd/bcm2835_sdhost.h"
18 
19 #define TYPE_BCM2835_SDHOST_BUS "bcm2835-sdhost-bus"
20 #define BCM2835_SDHOST_BUS(obj) \
21     OBJECT_CHECK(SDBus, (obj), TYPE_BCM2835_SDHOST_BUS)
22 
23 #define SDCMD  0x00 /* Command to SD card              - 16 R/W */
24 #define SDARG  0x04 /* Argument to SD card             - 32 R/W */
25 #define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */
26 #define SDCDIV 0x0c /* Start value for clock divider   - 11 R/W */
27 #define SDRSP0 0x10 /* SD card rsp (31:0)         - 32 R   */
28 #define SDRSP1 0x14 /* SD card rsp (63:32)        - 32 R   */
29 #define SDRSP2 0x18 /* SD card rsp (95:64)        - 32 R   */
30 #define SDRSP3 0x1c /* SD card rsp (127:96)       - 32 R   */
31 #define SDHSTS 0x20 /* SD host status                  - 11 R   */
32 #define SDVDD  0x30 /* SD card power control           -  1 R/W */
33 #define SDEDM  0x34 /* Emergency Debug Mode            - 13 R/W */
34 #define SDHCFG 0x38 /* Host configuration              -  2 R/W */
35 #define SDHBCT 0x3c /* Host byte count (debug)         - 32 R/W */
36 #define SDDATA 0x40 /* Data to/from SD card            - 32 R/W */
37 #define SDHBLC 0x50 /* Host block count (SDIO/SDHC)    -  9 R/W */
38 
39 #define SDCMD_NEW_FLAG                  0x8000
40 #define SDCMD_FAIL_FLAG                 0x4000
41 #define SDCMD_BUSYWAIT                  0x800
42 #define SDCMD_NO_RESPONSE               0x400
43 #define SDCMD_LONG_RESPONSE             0x200
44 #define SDCMD_WRITE_CMD                 0x80
45 #define SDCMD_READ_CMD                  0x40
46 #define SDCMD_CMD_MASK                  0x3f
47 
48 #define SDCDIV_MAX_CDIV                 0x7ff
49 
50 #define SDHSTS_BUSY_IRPT                0x400
51 #define SDHSTS_BLOCK_IRPT               0x200
52 #define SDHSTS_SDIO_IRPT                0x100
53 #define SDHSTS_REW_TIME_OUT             0x80
54 #define SDHSTS_CMD_TIME_OUT             0x40
55 #define SDHSTS_CRC16_ERROR              0x20
56 #define SDHSTS_CRC7_ERROR               0x10
57 #define SDHSTS_FIFO_ERROR               0x08
58 /* Reserved */
59 /* Reserved */
60 #define SDHSTS_DATA_FLAG                0x01
61 
62 #define SDHCFG_BUSY_IRPT_EN     (1 << 10)
63 #define SDHCFG_BLOCK_IRPT_EN    (1 << 8)
64 #define SDHCFG_SDIO_IRPT_EN     (1 << 5)
65 #define SDHCFG_DATA_IRPT_EN     (1 << 4)
66 #define SDHCFG_SLOW_CARD        (1 << 3)
67 #define SDHCFG_WIDE_EXT_BUS     (1 << 2)
68 #define SDHCFG_WIDE_INT_BUS     (1 << 1)
69 #define SDHCFG_REL_CMD_LINE     (1 << 0)
70 
71 #define SDEDM_FORCE_DATA_MODE   (1 << 19)
72 #define SDEDM_CLOCK_PULSE       (1 << 20)
73 #define SDEDM_BYPASS            (1 << 21)
74 
75 #define SDEDM_WRITE_THRESHOLD_SHIFT 9
76 #define SDEDM_READ_THRESHOLD_SHIFT 14
77 #define SDEDM_THRESHOLD_MASK     0x1f
78 
79 #define SDEDM_FSM_MASK           0xf
80 #define SDEDM_FSM_IDENTMODE      0x0
81 #define SDEDM_FSM_DATAMODE       0x1
82 #define SDEDM_FSM_READDATA       0x2
83 #define SDEDM_FSM_WRITEDATA      0x3
84 #define SDEDM_FSM_READWAIT       0x4
85 #define SDEDM_FSM_READCRC        0x5
86 #define SDEDM_FSM_WRITECRC       0x6
87 #define SDEDM_FSM_WRITEWAIT1     0x7
88 #define SDEDM_FSM_POWERDOWN      0x8
89 #define SDEDM_FSM_POWERUP        0x9
90 #define SDEDM_FSM_WRITESTART1    0xa
91 #define SDEDM_FSM_WRITESTART2    0xb
92 #define SDEDM_FSM_GENPULSES      0xc
93 #define SDEDM_FSM_WRITEWAIT2     0xd
94 #define SDEDM_FSM_STARTPOWDOWN   0xf
95 
96 #define SDDATA_FIFO_WORDS        16
97 
98 static void bcm2835_sdhost_update_irq(BCM2835SDHostState *s)
99 {
100     uint32_t irq = s->status &
101         (SDHSTS_BUSY_IRPT | SDHSTS_BLOCK_IRPT | SDHSTS_SDIO_IRPT);
102     qemu_set_irq(s->irq, !!irq);
103 }
104 
105 static void bcm2835_sdhost_send_command(BCM2835SDHostState *s)
106 {
107     SDRequest request;
108     uint8_t rsp[16];
109     int rlen;
110 
111     request.cmd = s->cmd & SDCMD_CMD_MASK;
112     request.arg = s->cmdarg;
113 
114     rlen = sdbus_do_command(&s->sdbus, &request, rsp);
115     if (rlen < 0) {
116         goto error;
117     }
118     if (!(s->cmd & SDCMD_NO_RESPONSE)) {
119 #define RWORD(n) (((uint32_t)rsp[n] << 24) | (rsp[n + 1] << 16) \
120                   | (rsp[n + 2] << 8) | rsp[n + 3])
121         if (rlen == 0 || (rlen == 4 && (s->cmd & SDCMD_LONG_RESPONSE))) {
122             goto error;
123         }
124         if (rlen != 4 && rlen != 16) {
125             goto error;
126         }
127         if (rlen == 4) {
128             s->rsp[0] = RWORD(0);
129             s->rsp[1] = s->rsp[2] = s->rsp[3] = 0;
130         } else {
131             s->rsp[0] = RWORD(12);
132             s->rsp[1] = RWORD(8);
133             s->rsp[2] = RWORD(4);
134             s->rsp[3] = RWORD(0);
135         }
136 #undef RWORD
137     }
138     return;
139 
140 error:
141     s->cmd |= SDCMD_FAIL_FLAG;
142     s->status |= SDHSTS_CMD_TIME_OUT;
143 }
144 
145 static void bcm2835_sdhost_fifo_push(BCM2835SDHostState *s, uint32_t value)
146 {
147     int n;
148 
149     if (s->fifo_len == BCM2835_SDHOST_FIFO_LEN) {
150         /* FIFO overflow */
151         return;
152     }
153     n = (s->fifo_pos + s->fifo_len) & (BCM2835_SDHOST_FIFO_LEN - 1);
154     s->fifo_len++;
155     s->fifo[n] = value;
156 }
157 
158 static uint32_t bcm2835_sdhost_fifo_pop(BCM2835SDHostState *s)
159 {
160     uint32_t value;
161 
162     if (s->fifo_len == 0) {
163         /* FIFO underflow */
164         return 0;
165     }
166     value = s->fifo[s->fifo_pos];
167     s->fifo_len--;
168     s->fifo_pos = (s->fifo_pos + 1) & (BCM2835_SDHOST_FIFO_LEN - 1);
169     return value;
170 }
171 
172 static void bcm2835_sdhost_fifo_run(BCM2835SDHostState *s)
173 {
174     uint32_t value = 0;
175     int n;
176     int is_read;
177 
178     is_read = (s->cmd & SDCMD_READ_CMD) != 0;
179     if (s->datacnt != 0 && (!is_read || sdbus_data_ready(&s->sdbus))) {
180         if (is_read) {
181             n = 0;
182             while (s->datacnt && s->fifo_len < BCM2835_SDHOST_FIFO_LEN) {
183                 value |= (uint32_t)sdbus_read_data(&s->sdbus) << (n * 8);
184                 s->datacnt--;
185                 n++;
186                 if (n == 4) {
187                     bcm2835_sdhost_fifo_push(s, value);
188                     n = 0;
189                     value = 0;
190                 }
191             }
192             if (n != 0) {
193                 bcm2835_sdhost_fifo_push(s, value);
194             }
195         } else { /* write */
196             n = 0;
197             while (s->datacnt > 0 && (s->fifo_len > 0 || n > 0)) {
198                 if (n == 0) {
199                     value = bcm2835_sdhost_fifo_pop(s);
200                     n = 4;
201                 }
202                 n--;
203                 s->datacnt--;
204                 sdbus_write_data(&s->sdbus, value & 0xff);
205                 value >>= 8;
206             }
207         }
208     }
209     if (s->datacnt == 0) {
210         s->status |= SDHSTS_DATA_FLAG;
211 
212         s->edm &= ~0xf;
213         s->edm |= SDEDM_FSM_DATAMODE;
214 
215         if (s->config & SDHCFG_DATA_IRPT_EN) {
216             s->status |= SDHSTS_SDIO_IRPT;
217         }
218 
219         if ((s->cmd & SDCMD_BUSYWAIT) && (s->config & SDHCFG_BUSY_IRPT_EN)) {
220             s->status |= SDHSTS_BUSY_IRPT;
221         }
222 
223         if ((s->cmd & SDCMD_WRITE_CMD) && (s->config & SDHCFG_BLOCK_IRPT_EN)) {
224             s->status |= SDHSTS_BLOCK_IRPT;
225         }
226 
227         bcm2835_sdhost_update_irq(s);
228     }
229 
230     s->edm &= ~(0x1f << 4);
231     s->edm |= ((s->fifo_len & 0x1f) << 4);
232 }
233 
234 static uint64_t bcm2835_sdhost_read(void *opaque, hwaddr offset,
235     unsigned size)
236 {
237     BCM2835SDHostState *s = (BCM2835SDHostState *)opaque;
238     uint32_t res = 0;
239 
240     switch (offset) {
241     case SDCMD:
242         res = s->cmd;
243         break;
244     case SDHSTS:
245         res = s->status;
246         break;
247     case SDRSP0:
248         res = s->rsp[0];
249         break;
250     case SDRSP1:
251         res = s->rsp[1];
252         break;
253     case SDRSP2:
254         res = s->rsp[2];
255         break;
256     case SDRSP3:
257         res = s->rsp[3];
258         break;
259     case SDEDM:
260         res = s->edm;
261         break;
262     case SDVDD:
263         res = s->vdd;
264         break;
265     case SDDATA:
266         res = bcm2835_sdhost_fifo_pop(s);
267         bcm2835_sdhost_fifo_run(s);
268         break;
269     case SDHBCT:
270         res = s->hbct;
271         break;
272     case SDHBLC:
273         res = s->hblc;
274         break;
275 
276     default:
277         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
278                       __func__, offset);
279         res = 0;
280         break;
281     }
282 
283     return res;
284 }
285 
286 static void bcm2835_sdhost_write(void *opaque, hwaddr offset,
287     uint64_t value, unsigned size)
288 {
289     BCM2835SDHostState *s = (BCM2835SDHostState *)opaque;
290 
291     switch (offset) {
292     case SDCMD:
293         s->cmd = value;
294         if (value & SDCMD_NEW_FLAG) {
295             bcm2835_sdhost_send_command(s);
296             bcm2835_sdhost_fifo_run(s);
297             s->cmd &= ~SDCMD_NEW_FLAG;
298         }
299         break;
300     case SDTOUT:
301         break;
302     case SDCDIV:
303         break;
304     case SDHSTS:
305         s->status &= ~value;
306         bcm2835_sdhost_update_irq(s);
307         break;
308     case SDARG:
309         s->cmdarg = value;
310         break;
311     case SDEDM:
312         if ((value & 0xf) == 0xf) {
313             /* power down */
314             value &= ~0xf;
315         }
316         s->edm = value;
317         break;
318     case SDHCFG:
319         s->config = value;
320         bcm2835_sdhost_fifo_run(s);
321         break;
322     case SDVDD:
323         s->vdd = value;
324         break;
325     case SDDATA:
326         bcm2835_sdhost_fifo_push(s, value);
327         bcm2835_sdhost_fifo_run(s);
328         break;
329     case SDHBCT:
330         s->hbct = value;
331         break;
332     case SDHBLC:
333         s->hblc = value;
334         s->datacnt = s->hblc * s->hbct;
335         bcm2835_sdhost_fifo_run(s);
336         break;
337 
338     default:
339         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
340                       __func__, offset);
341         break;
342     }
343 }
344 
345 static const MemoryRegionOps bcm2835_sdhost_ops = {
346     .read = bcm2835_sdhost_read,
347     .write = bcm2835_sdhost_write,
348     .endianness = DEVICE_NATIVE_ENDIAN,
349 };
350 
351 static const VMStateDescription vmstate_bcm2835_sdhost = {
352     .name = TYPE_BCM2835_SDHOST,
353     .version_id = 1,
354     .minimum_version_id = 1,
355     .fields = (VMStateField[]) {
356         VMSTATE_UINT32(cmd, BCM2835SDHostState),
357         VMSTATE_UINT32(cmdarg, BCM2835SDHostState),
358         VMSTATE_UINT32(status, BCM2835SDHostState),
359         VMSTATE_UINT32_ARRAY(rsp, BCM2835SDHostState, 4),
360         VMSTATE_UINT32(config, BCM2835SDHostState),
361         VMSTATE_UINT32(edm, BCM2835SDHostState),
362         VMSTATE_UINT32(vdd, BCM2835SDHostState),
363         VMSTATE_UINT32(hbct, BCM2835SDHostState),
364         VMSTATE_UINT32(hblc, BCM2835SDHostState),
365         VMSTATE_INT32(fifo_pos, BCM2835SDHostState),
366         VMSTATE_INT32(fifo_len, BCM2835SDHostState),
367         VMSTATE_UINT32_ARRAY(fifo, BCM2835SDHostState, BCM2835_SDHOST_FIFO_LEN),
368         VMSTATE_UINT32(datacnt, BCM2835SDHostState),
369         VMSTATE_END_OF_LIST()
370     }
371 };
372 
373 static void bcm2835_sdhost_init(Object *obj)
374 {
375     BCM2835SDHostState *s = BCM2835_SDHOST(obj);
376 
377     qbus_create_inplace(&s->sdbus, sizeof(s->sdbus),
378                         TYPE_BCM2835_SDHOST_BUS, DEVICE(s), "sd-bus");
379 
380     memory_region_init_io(&s->iomem, obj, &bcm2835_sdhost_ops, s,
381                           TYPE_BCM2835_SDHOST, 0x1000);
382     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
383     sysbus_init_irq(SYS_BUS_DEVICE(s), &s->irq);
384 }
385 
386 static void bcm2835_sdhost_reset(DeviceState *dev)
387 {
388     BCM2835SDHostState *s = BCM2835_SDHOST(dev);
389 
390     s->cmd = 0;
391     s->cmdarg = 0;
392     s->edm = 0x0000c60f;
393     s->config = 0;
394     s->hbct = 0;
395     s->hblc = 0;
396     s->datacnt = 0;
397     s->fifo_pos = 0;
398     s->fifo_len = 0;
399 }
400 
401 static void bcm2835_sdhost_class_init(ObjectClass *klass, void *data)
402 {
403     DeviceClass *dc = DEVICE_CLASS(klass);
404 
405     dc->reset = bcm2835_sdhost_reset;
406     dc->vmsd = &vmstate_bcm2835_sdhost;
407 }
408 
409 static TypeInfo bcm2835_sdhost_info = {
410     .name          = TYPE_BCM2835_SDHOST,
411     .parent        = TYPE_SYS_BUS_DEVICE,
412     .instance_size = sizeof(BCM2835SDHostState),
413     .class_init    = bcm2835_sdhost_class_init,
414     .instance_init = bcm2835_sdhost_init,
415 };
416 
417 static const TypeInfo bcm2835_sdhost_bus_info = {
418     .name = TYPE_BCM2835_SDHOST_BUS,
419     .parent = TYPE_SD_BUS,
420     .instance_size = sizeof(SDBus),
421 };
422 
423 static void bcm2835_sdhost_register_types(void)
424 {
425     type_register_static(&bcm2835_sdhost_info);
426     type_register_static(&bcm2835_sdhost_bus_info);
427 }
428 
429 type_init(bcm2835_sdhost_register_types)
430