xref: /openbmc/qemu/hw/sd/bcm2835_sdhost.c (revision 59a3a1c0)
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 "qemu/module.h"
17 #include "sysemu/blockdev.h"
18 #include "hw/irq.h"
19 #include "hw/sd/bcm2835_sdhost.h"
20 #include "migration/vmstate.h"
21 #include "trace.h"
22 
23 #define TYPE_BCM2835_SDHOST_BUS "bcm2835-sdhost-bus"
24 #define BCM2835_SDHOST_BUS(obj) \
25     OBJECT_CHECK(SDBus, (obj), TYPE_BCM2835_SDHOST_BUS)
26 
27 #define SDCMD  0x00 /* Command to SD card              - 16 R/W */
28 #define SDARG  0x04 /* Argument to SD card             - 32 R/W */
29 #define SDTOUT 0x08 /* Start value for timeout counter - 32 R/W */
30 #define SDCDIV 0x0c /* Start value for clock divider   - 11 R/W */
31 #define SDRSP0 0x10 /* SD card rsp (31:0)         - 32 R   */
32 #define SDRSP1 0x14 /* SD card rsp (63:32)        - 32 R   */
33 #define SDRSP2 0x18 /* SD card rsp (95:64)        - 32 R   */
34 #define SDRSP3 0x1c /* SD card rsp (127:96)       - 32 R   */
35 #define SDHSTS 0x20 /* SD host status                  - 11 R   */
36 #define SDVDD  0x30 /* SD card power control           -  1 R/W */
37 #define SDEDM  0x34 /* Emergency Debug Mode            - 13 R/W */
38 #define SDHCFG 0x38 /* Host configuration              -  2 R/W */
39 #define SDHBCT 0x3c /* Host byte count (debug)         - 32 R/W */
40 #define SDDATA 0x40 /* Data to/from SD card            - 32 R/W */
41 #define SDHBLC 0x50 /* Host block count (SDIO/SDHC)    -  9 R/W */
42 
43 #define SDCMD_NEW_FLAG                  0x8000
44 #define SDCMD_FAIL_FLAG                 0x4000
45 #define SDCMD_BUSYWAIT                  0x800
46 #define SDCMD_NO_RESPONSE               0x400
47 #define SDCMD_LONG_RESPONSE             0x200
48 #define SDCMD_WRITE_CMD                 0x80
49 #define SDCMD_READ_CMD                  0x40
50 #define SDCMD_CMD_MASK                  0x3f
51 
52 #define SDCDIV_MAX_CDIV                 0x7ff
53 
54 #define SDHSTS_BUSY_IRPT                0x400
55 #define SDHSTS_BLOCK_IRPT               0x200
56 #define SDHSTS_SDIO_IRPT                0x100
57 #define SDHSTS_REW_TIME_OUT             0x80
58 #define SDHSTS_CMD_TIME_OUT             0x40
59 #define SDHSTS_CRC16_ERROR              0x20
60 #define SDHSTS_CRC7_ERROR               0x10
61 #define SDHSTS_FIFO_ERROR               0x08
62 /* Reserved */
63 /* Reserved */
64 #define SDHSTS_DATA_FLAG                0x01
65 
66 #define SDHCFG_BUSY_IRPT_EN     (1 << 10)
67 #define SDHCFG_BLOCK_IRPT_EN    (1 << 8)
68 #define SDHCFG_SDIO_IRPT_EN     (1 << 5)
69 #define SDHCFG_DATA_IRPT_EN     (1 << 4)
70 #define SDHCFG_SLOW_CARD        (1 << 3)
71 #define SDHCFG_WIDE_EXT_BUS     (1 << 2)
72 #define SDHCFG_WIDE_INT_BUS     (1 << 1)
73 #define SDHCFG_REL_CMD_LINE     (1 << 0)
74 
75 #define SDEDM_FORCE_DATA_MODE   (1 << 19)
76 #define SDEDM_CLOCK_PULSE       (1 << 20)
77 #define SDEDM_BYPASS            (1 << 21)
78 
79 #define SDEDM_WRITE_THRESHOLD_SHIFT 9
80 #define SDEDM_READ_THRESHOLD_SHIFT 14
81 #define SDEDM_THRESHOLD_MASK     0x1f
82 
83 #define SDEDM_FSM_MASK           0xf
84 #define SDEDM_FSM_IDENTMODE      0x0
85 #define SDEDM_FSM_DATAMODE       0x1
86 #define SDEDM_FSM_READDATA       0x2
87 #define SDEDM_FSM_WRITEDATA      0x3
88 #define SDEDM_FSM_READWAIT       0x4
89 #define SDEDM_FSM_READCRC        0x5
90 #define SDEDM_FSM_WRITECRC       0x6
91 #define SDEDM_FSM_WRITEWAIT1     0x7
92 #define SDEDM_FSM_POWERDOWN      0x8
93 #define SDEDM_FSM_POWERUP        0x9
94 #define SDEDM_FSM_WRITESTART1    0xa
95 #define SDEDM_FSM_WRITESTART2    0xb
96 #define SDEDM_FSM_GENPULSES      0xc
97 #define SDEDM_FSM_WRITEWAIT2     0xd
98 #define SDEDM_FSM_STARTPOWDOWN   0xf
99 
100 #define SDDATA_FIFO_WORDS        16
101 
102 static void bcm2835_sdhost_update_irq(BCM2835SDHostState *s)
103 {
104     uint32_t irq = s->status &
105         (SDHSTS_BUSY_IRPT | SDHSTS_BLOCK_IRPT | SDHSTS_SDIO_IRPT);
106     trace_bcm2835_sdhost_update_irq(irq);
107     qemu_set_irq(s->irq, !!irq);
108 }
109 
110 static void bcm2835_sdhost_send_command(BCM2835SDHostState *s)
111 {
112     SDRequest request;
113     uint8_t rsp[16];
114     int rlen;
115 
116     request.cmd = s->cmd & SDCMD_CMD_MASK;
117     request.arg = s->cmdarg;
118 
119     rlen = sdbus_do_command(&s->sdbus, &request, rsp);
120     if (rlen < 0) {
121         goto error;
122     }
123     if (!(s->cmd & SDCMD_NO_RESPONSE)) {
124         if (rlen == 0 || (rlen == 4 && (s->cmd & SDCMD_LONG_RESPONSE))) {
125             goto error;
126         }
127         if (rlen != 4 && rlen != 16) {
128             goto error;
129         }
130         if (rlen == 4) {
131             s->rsp[0] = ldl_be_p(&rsp[0]);
132             s->rsp[1] = s->rsp[2] = s->rsp[3] = 0;
133         } else {
134             s->rsp[0] = ldl_be_p(&rsp[12]);
135             s->rsp[1] = ldl_be_p(&rsp[8]);
136             s->rsp[2] = ldl_be_p(&rsp[4]);
137             s->rsp[3] = ldl_be_p(&rsp[0]);
138         }
139     }
140     /* We never really delay commands, so if this was a 'busywait' command
141      * then we've completed it now and can raise the interrupt.
142      */
143     if ((s->cmd & SDCMD_BUSYWAIT) && (s->config & SDHCFG_BUSY_IRPT_EN)) {
144         s->status |= SDHSTS_BUSY_IRPT;
145     }
146     return;
147 
148 error:
149     s->cmd |= SDCMD_FAIL_FLAG;
150     s->status |= SDHSTS_CMD_TIME_OUT;
151 }
152 
153 static void bcm2835_sdhost_fifo_push(BCM2835SDHostState *s, uint32_t value)
154 {
155     int n;
156 
157     if (s->fifo_len == BCM2835_SDHOST_FIFO_LEN) {
158         /* FIFO overflow */
159         return;
160     }
161     n = (s->fifo_pos + s->fifo_len) & (BCM2835_SDHOST_FIFO_LEN - 1);
162     s->fifo_len++;
163     s->fifo[n] = value;
164 }
165 
166 static uint32_t bcm2835_sdhost_fifo_pop(BCM2835SDHostState *s)
167 {
168     uint32_t value;
169 
170     if (s->fifo_len == 0) {
171         /* FIFO underflow */
172         return 0;
173     }
174     value = s->fifo[s->fifo_pos];
175     s->fifo_len--;
176     s->fifo_pos = (s->fifo_pos + 1) & (BCM2835_SDHOST_FIFO_LEN - 1);
177     return value;
178 }
179 
180 static void bcm2835_sdhost_fifo_run(BCM2835SDHostState *s)
181 {
182     uint32_t value = 0;
183     int n;
184     int is_read;
185     int is_write;
186 
187     is_read = (s->cmd & SDCMD_READ_CMD) != 0;
188     is_write = (s->cmd & SDCMD_WRITE_CMD) != 0;
189     if (s->datacnt != 0 && (is_write || sdbus_data_ready(&s->sdbus))) {
190         if (is_read) {
191             n = 0;
192             while (s->datacnt && s->fifo_len < BCM2835_SDHOST_FIFO_LEN) {
193                 value |= (uint32_t)sdbus_read_data(&s->sdbus) << (n * 8);
194                 s->datacnt--;
195                 n++;
196                 if (n == 4) {
197                     bcm2835_sdhost_fifo_push(s, value);
198                     s->status |= SDHSTS_DATA_FLAG;
199                     if (s->config & SDHCFG_DATA_IRPT_EN) {
200                         s->status |= SDHSTS_SDIO_IRPT;
201                     }
202                     n = 0;
203                     value = 0;
204                 }
205             }
206             if (n != 0) {
207                 bcm2835_sdhost_fifo_push(s, value);
208                 s->status |= SDHSTS_DATA_FLAG;
209                 if (s->config & SDHCFG_DATA_IRPT_EN) {
210                     s->status |= SDHSTS_SDIO_IRPT;
211                 }
212             }
213         } else if (is_write) { /* write */
214             n = 0;
215             while (s->datacnt > 0 && (s->fifo_len > 0 || n > 0)) {
216                 if (n == 0) {
217                     value = bcm2835_sdhost_fifo_pop(s);
218                     s->status |= SDHSTS_DATA_FLAG;
219                     if (s->config & SDHCFG_DATA_IRPT_EN) {
220                         s->status |= SDHSTS_SDIO_IRPT;
221                     }
222                     n = 4;
223                 }
224                 n--;
225                 s->datacnt--;
226                 sdbus_write_data(&s->sdbus, value & 0xff);
227                 value >>= 8;
228             }
229         }
230         if (s->datacnt == 0) {
231             s->edm &= ~SDEDM_FSM_MASK;
232             s->edm |= SDEDM_FSM_DATAMODE;
233             trace_bcm2835_sdhost_edm_change("datacnt 0", s->edm);
234         }
235         if (is_write) {
236             /* set block interrupt at end of each block transfer */
237             if (s->hbct && s->datacnt % s->hbct == 0 &&
238                 (s->config & SDHCFG_BLOCK_IRPT_EN)) {
239                 s->status |= SDHSTS_BLOCK_IRPT;
240             }
241             /* set data interrupt after each transfer */
242             s->status |= SDHSTS_DATA_FLAG;
243             if (s->config & SDHCFG_DATA_IRPT_EN) {
244                 s->status |= SDHSTS_SDIO_IRPT;
245             }
246         }
247     }
248 
249     bcm2835_sdhost_update_irq(s);
250 
251     s->edm &= ~(0x1f << 4);
252     s->edm |= ((s->fifo_len & 0x1f) << 4);
253     trace_bcm2835_sdhost_edm_change("fifo run", s->edm);
254 }
255 
256 static uint64_t bcm2835_sdhost_read(void *opaque, hwaddr offset,
257     unsigned size)
258 {
259     BCM2835SDHostState *s = (BCM2835SDHostState *)opaque;
260     uint32_t res = 0;
261 
262     switch (offset) {
263     case SDCMD:
264         res = s->cmd;
265         break;
266     case SDHSTS:
267         res = s->status;
268         break;
269     case SDRSP0:
270         res = s->rsp[0];
271         break;
272     case SDRSP1:
273         res = s->rsp[1];
274         break;
275     case SDRSP2:
276         res = s->rsp[2];
277         break;
278     case SDRSP3:
279         res = s->rsp[3];
280         break;
281     case SDEDM:
282         res = s->edm;
283         break;
284     case SDVDD:
285         res = s->vdd;
286         break;
287     case SDDATA:
288         res = bcm2835_sdhost_fifo_pop(s);
289         bcm2835_sdhost_fifo_run(s);
290         break;
291     case SDHBCT:
292         res = s->hbct;
293         break;
294     case SDHBLC:
295         res = s->hblc;
296         break;
297 
298     default:
299         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
300                       __func__, offset);
301         res = 0;
302         break;
303     }
304 
305     trace_bcm2835_sdhost_read(offset, res, size);
306 
307     return res;
308 }
309 
310 static void bcm2835_sdhost_write(void *opaque, hwaddr offset,
311     uint64_t value, unsigned size)
312 {
313     BCM2835SDHostState *s = (BCM2835SDHostState *)opaque;
314 
315     trace_bcm2835_sdhost_write(offset, value, size);
316 
317     switch (offset) {
318     case SDCMD:
319         s->cmd = value;
320         if (value & SDCMD_NEW_FLAG) {
321             bcm2835_sdhost_send_command(s);
322             bcm2835_sdhost_fifo_run(s);
323             s->cmd &= ~SDCMD_NEW_FLAG;
324         }
325         break;
326     case SDTOUT:
327         break;
328     case SDCDIV:
329         break;
330     case SDHSTS:
331         s->status &= ~value;
332         bcm2835_sdhost_update_irq(s);
333         break;
334     case SDARG:
335         s->cmdarg = value;
336         break;
337     case SDEDM:
338         if ((value & 0xf) == 0xf) {
339             /* power down */
340             value &= ~0xf;
341         }
342         s->edm = value;
343         trace_bcm2835_sdhost_edm_change("guest register write", s->edm);
344         break;
345     case SDHCFG:
346         s->config = value;
347         bcm2835_sdhost_fifo_run(s);
348         break;
349     case SDVDD:
350         s->vdd = value;
351         break;
352     case SDDATA:
353         bcm2835_sdhost_fifo_push(s, value);
354         bcm2835_sdhost_fifo_run(s);
355         break;
356     case SDHBCT:
357         s->hbct = value;
358         break;
359     case SDHBLC:
360         s->hblc = value;
361         s->datacnt = s->hblc * s->hbct;
362         bcm2835_sdhost_fifo_run(s);
363         break;
364 
365     default:
366         qemu_log_mask(LOG_GUEST_ERROR, "%s: Bad offset %"HWADDR_PRIx"\n",
367                       __func__, offset);
368         break;
369     }
370 }
371 
372 static const MemoryRegionOps bcm2835_sdhost_ops = {
373     .read = bcm2835_sdhost_read,
374     .write = bcm2835_sdhost_write,
375     .endianness = DEVICE_NATIVE_ENDIAN,
376 };
377 
378 static const VMStateDescription vmstate_bcm2835_sdhost = {
379     .name = TYPE_BCM2835_SDHOST,
380     .version_id = 1,
381     .minimum_version_id = 1,
382     .fields = (VMStateField[]) {
383         VMSTATE_UINT32(cmd, BCM2835SDHostState),
384         VMSTATE_UINT32(cmdarg, BCM2835SDHostState),
385         VMSTATE_UINT32(status, BCM2835SDHostState),
386         VMSTATE_UINT32_ARRAY(rsp, BCM2835SDHostState, 4),
387         VMSTATE_UINT32(config, BCM2835SDHostState),
388         VMSTATE_UINT32(edm, BCM2835SDHostState),
389         VMSTATE_UINT32(vdd, BCM2835SDHostState),
390         VMSTATE_UINT32(hbct, BCM2835SDHostState),
391         VMSTATE_UINT32(hblc, BCM2835SDHostState),
392         VMSTATE_INT32(fifo_pos, BCM2835SDHostState),
393         VMSTATE_INT32(fifo_len, BCM2835SDHostState),
394         VMSTATE_UINT32_ARRAY(fifo, BCM2835SDHostState, BCM2835_SDHOST_FIFO_LEN),
395         VMSTATE_UINT32(datacnt, BCM2835SDHostState),
396         VMSTATE_END_OF_LIST()
397     }
398 };
399 
400 static void bcm2835_sdhost_init(Object *obj)
401 {
402     BCM2835SDHostState *s = BCM2835_SDHOST(obj);
403 
404     qbus_create_inplace(&s->sdbus, sizeof(s->sdbus),
405                         TYPE_BCM2835_SDHOST_BUS, DEVICE(s), "sd-bus");
406 
407     memory_region_init_io(&s->iomem, obj, &bcm2835_sdhost_ops, s,
408                           TYPE_BCM2835_SDHOST, 0x1000);
409     sysbus_init_mmio(SYS_BUS_DEVICE(s), &s->iomem);
410     sysbus_init_irq(SYS_BUS_DEVICE(s), &s->irq);
411 }
412 
413 static void bcm2835_sdhost_reset(DeviceState *dev)
414 {
415     BCM2835SDHostState *s = BCM2835_SDHOST(dev);
416 
417     s->cmd = 0;
418     s->cmdarg = 0;
419     s->edm = 0x0000c60f;
420     trace_bcm2835_sdhost_edm_change("device reset", s->edm);
421     s->config = 0;
422     s->hbct = 0;
423     s->hblc = 0;
424     s->datacnt = 0;
425     s->fifo_pos = 0;
426     s->fifo_len = 0;
427 }
428 
429 static void bcm2835_sdhost_class_init(ObjectClass *klass, void *data)
430 {
431     DeviceClass *dc = DEVICE_CLASS(klass);
432 
433     dc->reset = bcm2835_sdhost_reset;
434     dc->vmsd = &vmstate_bcm2835_sdhost;
435 }
436 
437 static TypeInfo bcm2835_sdhost_info = {
438     .name          = TYPE_BCM2835_SDHOST,
439     .parent        = TYPE_SYS_BUS_DEVICE,
440     .instance_size = sizeof(BCM2835SDHostState),
441     .class_init    = bcm2835_sdhost_class_init,
442     .instance_init = bcm2835_sdhost_init,
443 };
444 
445 static const TypeInfo bcm2835_sdhost_bus_info = {
446     .name = TYPE_BCM2835_SDHOST_BUS,
447     .parent = TYPE_SD_BUS,
448     .instance_size = sizeof(SDBus),
449 };
450 
451 static void bcm2835_sdhost_register_types(void)
452 {
453     type_register_static(&bcm2835_sdhost_info);
454     type_register_static(&bcm2835_sdhost_bus_info);
455 }
456 
457 type_init(bcm2835_sdhost_register_types)
458