xref: /openbmc/linux/drivers/mmc/host/cavium.c (revision 6b0e0fce)
1 /*
2  * Shared part of driver for MMC/SDHC controller on Cavium OCTEON and
3  * ThunderX SOCs.
4  *
5  * This file is subject to the terms and conditions of the GNU General Public
6  * License.  See the file "COPYING" in the main directory of this archive
7  * for more details.
8  *
9  * Copyright (C) 2012-2017 Cavium Inc.
10  * Authors:
11  *   David Daney <david.daney@cavium.com>
12  *   Peter Swain <pswain@cavium.com>
13  *   Steven J. Hill <steven.hill@cavium.com>
14  *   Jan Glauber <jglauber@cavium.com>
15  */
16 #include <linux/bitfield.h>
17 #include <linux/delay.h>
18 #include <linux/dma-direction.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/gpio/consumer.h>
21 #include <linux/interrupt.h>
22 #include <linux/mmc/mmc.h>
23 #include <linux/mmc/slot-gpio.h>
24 #include <linux/module.h>
25 #include <linux/regulator/consumer.h>
26 #include <linux/scatterlist.h>
27 #include <linux/time.h>
28 
29 #include "cavium.h"
30 
31 const char *cvm_mmc_irq_names[] = {
32 	"MMC Buffer",
33 	"MMC Command",
34 	"MMC DMA",
35 	"MMC Command Error",
36 	"MMC DMA Error",
37 	"MMC Switch",
38 	"MMC Switch Error",
39 	"MMC DMA int Fifo",
40 	"MMC DMA int",
41 };
42 
43 /*
44  * The Cavium MMC host hardware assumes that all commands have fixed
45  * command and response types.  These are correct if MMC devices are
46  * being used.  However, non-MMC devices like SD use command and
47  * response types that are unexpected by the host hardware.
48  *
49  * The command and response types can be overridden by supplying an
50  * XOR value that is applied to the type.  We calculate the XOR value
51  * from the values in this table and the flags passed from the MMC
52  * core.
53  */
54 static struct cvm_mmc_cr_type cvm_mmc_cr_types[] = {
55 	{0, 0},		/* CMD0 */
56 	{0, 3},		/* CMD1 */
57 	{0, 2},		/* CMD2 */
58 	{0, 1},		/* CMD3 */
59 	{0, 0},		/* CMD4 */
60 	{0, 1},		/* CMD5 */
61 	{0, 1},		/* CMD6 */
62 	{0, 1},		/* CMD7 */
63 	{1, 1},		/* CMD8 */
64 	{0, 2},		/* CMD9 */
65 	{0, 2},		/* CMD10 */
66 	{1, 1},		/* CMD11 */
67 	{0, 1},		/* CMD12 */
68 	{0, 1},		/* CMD13 */
69 	{1, 1},		/* CMD14 */
70 	{0, 0},		/* CMD15 */
71 	{0, 1},		/* CMD16 */
72 	{1, 1},		/* CMD17 */
73 	{1, 1},		/* CMD18 */
74 	{3, 1},		/* CMD19 */
75 	{2, 1},		/* CMD20 */
76 	{0, 0},		/* CMD21 */
77 	{0, 0},		/* CMD22 */
78 	{0, 1},		/* CMD23 */
79 	{2, 1},		/* CMD24 */
80 	{2, 1},		/* CMD25 */
81 	{2, 1},		/* CMD26 */
82 	{2, 1},		/* CMD27 */
83 	{0, 1},		/* CMD28 */
84 	{0, 1},		/* CMD29 */
85 	{1, 1},		/* CMD30 */
86 	{1, 1},		/* CMD31 */
87 	{0, 0},		/* CMD32 */
88 	{0, 0},		/* CMD33 */
89 	{0, 0},		/* CMD34 */
90 	{0, 1},		/* CMD35 */
91 	{0, 1},		/* CMD36 */
92 	{0, 0},		/* CMD37 */
93 	{0, 1},		/* CMD38 */
94 	{0, 4},		/* CMD39 */
95 	{0, 5},		/* CMD40 */
96 	{0, 0},		/* CMD41 */
97 	{2, 1},		/* CMD42 */
98 	{0, 0},		/* CMD43 */
99 	{0, 0},		/* CMD44 */
100 	{0, 0},		/* CMD45 */
101 	{0, 0},		/* CMD46 */
102 	{0, 0},		/* CMD47 */
103 	{0, 0},		/* CMD48 */
104 	{0, 0},		/* CMD49 */
105 	{0, 0},		/* CMD50 */
106 	{0, 0},		/* CMD51 */
107 	{0, 0},		/* CMD52 */
108 	{0, 0},		/* CMD53 */
109 	{0, 0},		/* CMD54 */
110 	{0, 1},		/* CMD55 */
111 	{0xff, 0xff},	/* CMD56 */
112 	{0, 0},		/* CMD57 */
113 	{0, 0},		/* CMD58 */
114 	{0, 0},		/* CMD59 */
115 	{0, 0},		/* CMD60 */
116 	{0, 0},		/* CMD61 */
117 	{0, 0},		/* CMD62 */
118 	{0, 0}		/* CMD63 */
119 };
120 
cvm_mmc_get_cr_mods(struct mmc_command * cmd)121 static struct cvm_mmc_cr_mods cvm_mmc_get_cr_mods(struct mmc_command *cmd)
122 {
123 	struct cvm_mmc_cr_type *cr;
124 	u8 hardware_ctype, hardware_rtype;
125 	u8 desired_ctype = 0, desired_rtype = 0;
126 	struct cvm_mmc_cr_mods r;
127 
128 	cr = cvm_mmc_cr_types + (cmd->opcode & 0x3f);
129 	hardware_ctype = cr->ctype;
130 	hardware_rtype = cr->rtype;
131 	if (cmd->opcode == MMC_GEN_CMD)
132 		hardware_ctype = (cmd->arg & 1) ? 1 : 2;
133 
134 	switch (mmc_cmd_type(cmd)) {
135 	case MMC_CMD_ADTC:
136 		desired_ctype = (cmd->data->flags & MMC_DATA_WRITE) ? 2 : 1;
137 		break;
138 	case MMC_CMD_AC:
139 	case MMC_CMD_BC:
140 	case MMC_CMD_BCR:
141 		desired_ctype = 0;
142 		break;
143 	}
144 
145 	switch (mmc_resp_type(cmd)) {
146 	case MMC_RSP_NONE:
147 		desired_rtype = 0;
148 		break;
149 	case MMC_RSP_R1:/* MMC_RSP_R5, MMC_RSP_R6, MMC_RSP_R7 */
150 	case MMC_RSP_R1B:
151 		desired_rtype = 1;
152 		break;
153 	case MMC_RSP_R2:
154 		desired_rtype = 2;
155 		break;
156 	case MMC_RSP_R3: /* MMC_RSP_R4 */
157 		desired_rtype = 3;
158 		break;
159 	}
160 	r.ctype_xor = desired_ctype ^ hardware_ctype;
161 	r.rtype_xor = desired_rtype ^ hardware_rtype;
162 	return r;
163 }
164 
check_switch_errors(struct cvm_mmc_host * host)165 static void check_switch_errors(struct cvm_mmc_host *host)
166 {
167 	u64 emm_switch;
168 
169 	emm_switch = readq(host->base + MIO_EMM_SWITCH(host));
170 	if (emm_switch & MIO_EMM_SWITCH_ERR0)
171 		dev_err(host->dev, "Switch power class error\n");
172 	if (emm_switch & MIO_EMM_SWITCH_ERR1)
173 		dev_err(host->dev, "Switch hs timing error\n");
174 	if (emm_switch & MIO_EMM_SWITCH_ERR2)
175 		dev_err(host->dev, "Switch bus width error\n");
176 }
177 
clear_bus_id(u64 * reg)178 static void clear_bus_id(u64 *reg)
179 {
180 	u64 bus_id_mask = GENMASK_ULL(61, 60);
181 
182 	*reg &= ~bus_id_mask;
183 }
184 
set_bus_id(u64 * reg,int bus_id)185 static void set_bus_id(u64 *reg, int bus_id)
186 {
187 	clear_bus_id(reg);
188 	*reg |= FIELD_PREP(GENMASK(61, 60), bus_id);
189 }
190 
get_bus_id(u64 reg)191 static int get_bus_id(u64 reg)
192 {
193 	return FIELD_GET(GENMASK_ULL(61, 60), reg);
194 }
195 
196 /*
197  * We never set the switch_exe bit since that would interfere
198  * with the commands send by the MMC core.
199  */
do_switch(struct cvm_mmc_host * host,u64 emm_switch)200 static void do_switch(struct cvm_mmc_host *host, u64 emm_switch)
201 {
202 	int retries = 100;
203 	u64 rsp_sts;
204 	int bus_id;
205 
206 	/*
207 	 * Modes setting only taken from slot 0. Work around that hardware
208 	 * issue by first switching to slot 0.
209 	 */
210 	bus_id = get_bus_id(emm_switch);
211 	clear_bus_id(&emm_switch);
212 	writeq(emm_switch, host->base + MIO_EMM_SWITCH(host));
213 
214 	set_bus_id(&emm_switch, bus_id);
215 	writeq(emm_switch, host->base + MIO_EMM_SWITCH(host));
216 
217 	/* wait for the switch to finish */
218 	do {
219 		rsp_sts = readq(host->base + MIO_EMM_RSP_STS(host));
220 		if (!(rsp_sts & MIO_EMM_RSP_STS_SWITCH_VAL))
221 			break;
222 		udelay(10);
223 	} while (--retries);
224 
225 	check_switch_errors(host);
226 }
227 
switch_val_changed(struct cvm_mmc_slot * slot,u64 new_val)228 static bool switch_val_changed(struct cvm_mmc_slot *slot, u64 new_val)
229 {
230 	/* Match BUS_ID, HS_TIMING, BUS_WIDTH, POWER_CLASS, CLK_HI, CLK_LO */
231 	u64 match = 0x3001070fffffffffull;
232 
233 	return (slot->cached_switch & match) != (new_val & match);
234 }
235 
set_wdog(struct cvm_mmc_slot * slot,unsigned int ns)236 static void set_wdog(struct cvm_mmc_slot *slot, unsigned int ns)
237 {
238 	u64 timeout;
239 
240 	if (!slot->clock)
241 		return;
242 
243 	if (ns)
244 		timeout = (slot->clock * ns) / NSEC_PER_SEC;
245 	else
246 		timeout = (slot->clock * 850ull) / 1000ull;
247 	writeq(timeout, slot->host->base + MIO_EMM_WDOG(slot->host));
248 }
249 
cvm_mmc_reset_bus(struct cvm_mmc_slot * slot)250 static void cvm_mmc_reset_bus(struct cvm_mmc_slot *slot)
251 {
252 	struct cvm_mmc_host *host = slot->host;
253 	u64 emm_switch, wdog;
254 
255 	emm_switch = readq(slot->host->base + MIO_EMM_SWITCH(host));
256 	emm_switch &= ~(MIO_EMM_SWITCH_EXE | MIO_EMM_SWITCH_ERR0 |
257 			MIO_EMM_SWITCH_ERR1 | MIO_EMM_SWITCH_ERR2);
258 	set_bus_id(&emm_switch, slot->bus_id);
259 
260 	wdog = readq(slot->host->base + MIO_EMM_WDOG(host));
261 	do_switch(slot->host, emm_switch);
262 
263 	slot->cached_switch = emm_switch;
264 
265 	msleep(20);
266 
267 	writeq(wdog, slot->host->base + MIO_EMM_WDOG(host));
268 }
269 
270 /* Switch to another slot if needed */
cvm_mmc_switch_to(struct cvm_mmc_slot * slot)271 static void cvm_mmc_switch_to(struct cvm_mmc_slot *slot)
272 {
273 	struct cvm_mmc_host *host = slot->host;
274 	struct cvm_mmc_slot *old_slot;
275 	u64 emm_sample, emm_switch;
276 
277 	if (slot->bus_id == host->last_slot)
278 		return;
279 
280 	if (host->last_slot >= 0 && host->slot[host->last_slot]) {
281 		old_slot = host->slot[host->last_slot];
282 		old_slot->cached_switch = readq(host->base + MIO_EMM_SWITCH(host));
283 		old_slot->cached_rca = readq(host->base + MIO_EMM_RCA(host));
284 	}
285 
286 	writeq(slot->cached_rca, host->base + MIO_EMM_RCA(host));
287 	emm_switch = slot->cached_switch;
288 	set_bus_id(&emm_switch, slot->bus_id);
289 	do_switch(host, emm_switch);
290 
291 	emm_sample = FIELD_PREP(MIO_EMM_SAMPLE_CMD_CNT, slot->cmd_cnt) |
292 		     FIELD_PREP(MIO_EMM_SAMPLE_DAT_CNT, slot->dat_cnt);
293 	writeq(emm_sample, host->base + MIO_EMM_SAMPLE(host));
294 
295 	host->last_slot = slot->bus_id;
296 }
297 
do_read(struct cvm_mmc_host * host,struct mmc_request * req,u64 dbuf)298 static void do_read(struct cvm_mmc_host *host, struct mmc_request *req,
299 		    u64 dbuf)
300 {
301 	struct sg_mapping_iter *smi = &host->smi;
302 	int data_len = req->data->blocks * req->data->blksz;
303 	int bytes_xfered, shift = -1;
304 	u64 dat = 0;
305 
306 	/* Auto inc from offset zero */
307 	writeq((0x10000 | (dbuf << 6)), host->base + MIO_EMM_BUF_IDX(host));
308 
309 	for (bytes_xfered = 0; bytes_xfered < data_len;) {
310 		if (smi->consumed >= smi->length) {
311 			if (!sg_miter_next(smi))
312 				break;
313 			smi->consumed = 0;
314 		}
315 
316 		if (shift < 0) {
317 			dat = readq(host->base + MIO_EMM_BUF_DAT(host));
318 			shift = 56;
319 		}
320 
321 		while (smi->consumed < smi->length && shift >= 0) {
322 			((u8 *)smi->addr)[smi->consumed] = (dat >> shift) & 0xff;
323 			bytes_xfered++;
324 			smi->consumed++;
325 			shift -= 8;
326 		}
327 	}
328 
329 	sg_miter_stop(smi);
330 	req->data->bytes_xfered = bytes_xfered;
331 	req->data->error = 0;
332 }
333 
do_write(struct mmc_request * req)334 static void do_write(struct mmc_request *req)
335 {
336 	req->data->bytes_xfered = req->data->blocks * req->data->blksz;
337 	req->data->error = 0;
338 }
339 
set_cmd_response(struct cvm_mmc_host * host,struct mmc_request * req,u64 rsp_sts)340 static void set_cmd_response(struct cvm_mmc_host *host, struct mmc_request *req,
341 			     u64 rsp_sts)
342 {
343 	u64 rsp_hi, rsp_lo;
344 
345 	if (!(rsp_sts & MIO_EMM_RSP_STS_RSP_VAL))
346 		return;
347 
348 	rsp_lo = readq(host->base + MIO_EMM_RSP_LO(host));
349 
350 	switch (FIELD_GET(MIO_EMM_RSP_STS_RSP_TYPE, rsp_sts)) {
351 	case 1:
352 	case 3:
353 		req->cmd->resp[0] = (rsp_lo >> 8) & 0xffffffff;
354 		req->cmd->resp[1] = 0;
355 		req->cmd->resp[2] = 0;
356 		req->cmd->resp[3] = 0;
357 		break;
358 	case 2:
359 		req->cmd->resp[3] = rsp_lo & 0xffffffff;
360 		req->cmd->resp[2] = (rsp_lo >> 32) & 0xffffffff;
361 		rsp_hi = readq(host->base + MIO_EMM_RSP_HI(host));
362 		req->cmd->resp[1] = rsp_hi & 0xffffffff;
363 		req->cmd->resp[0] = (rsp_hi >> 32) & 0xffffffff;
364 		break;
365 	}
366 }
367 
get_dma_dir(struct mmc_data * data)368 static int get_dma_dir(struct mmc_data *data)
369 {
370 	return (data->flags & MMC_DATA_WRITE) ? DMA_TO_DEVICE : DMA_FROM_DEVICE;
371 }
372 
finish_dma_single(struct cvm_mmc_host * host,struct mmc_data * data)373 static int finish_dma_single(struct cvm_mmc_host *host, struct mmc_data *data)
374 {
375 	data->bytes_xfered = data->blocks * data->blksz;
376 	data->error = 0;
377 	dma_unmap_sg(host->dev, data->sg, data->sg_len, get_dma_dir(data));
378 	return 1;
379 }
380 
finish_dma_sg(struct cvm_mmc_host * host,struct mmc_data * data)381 static int finish_dma_sg(struct cvm_mmc_host *host, struct mmc_data *data)
382 {
383 	u64 fifo_cfg;
384 	int count;
385 
386 	/* Check if there are any pending requests left */
387 	fifo_cfg = readq(host->dma_base + MIO_EMM_DMA_FIFO_CFG(host));
388 	count = FIELD_GET(MIO_EMM_DMA_FIFO_CFG_COUNT, fifo_cfg);
389 	if (count)
390 		dev_err(host->dev, "%u requests still pending\n", count);
391 
392 	data->bytes_xfered = data->blocks * data->blksz;
393 	data->error = 0;
394 
395 	/* Clear and disable FIFO */
396 	writeq(BIT_ULL(16), host->dma_base + MIO_EMM_DMA_FIFO_CFG(host));
397 	dma_unmap_sg(host->dev, data->sg, data->sg_len, get_dma_dir(data));
398 	return 1;
399 }
400 
finish_dma(struct cvm_mmc_host * host,struct mmc_data * data)401 static int finish_dma(struct cvm_mmc_host *host, struct mmc_data *data)
402 {
403 	if (host->use_sg && data->sg_len > 1)
404 		return finish_dma_sg(host, data);
405 	else
406 		return finish_dma_single(host, data);
407 }
408 
check_status(u64 rsp_sts)409 static int check_status(u64 rsp_sts)
410 {
411 	if (rsp_sts & MIO_EMM_RSP_STS_RSP_BAD_STS ||
412 	    rsp_sts & MIO_EMM_RSP_STS_RSP_CRC_ERR ||
413 	    rsp_sts & MIO_EMM_RSP_STS_BLK_CRC_ERR)
414 		return -EILSEQ;
415 	if (rsp_sts & MIO_EMM_RSP_STS_RSP_TIMEOUT ||
416 	    rsp_sts & MIO_EMM_RSP_STS_BLK_TIMEOUT)
417 		return -ETIMEDOUT;
418 	if (rsp_sts & MIO_EMM_RSP_STS_DBUF_ERR)
419 		return -EIO;
420 	return 0;
421 }
422 
423 /* Try to clean up failed DMA. */
cleanup_dma(struct cvm_mmc_host * host,u64 rsp_sts)424 static void cleanup_dma(struct cvm_mmc_host *host, u64 rsp_sts)
425 {
426 	u64 emm_dma;
427 
428 	emm_dma = readq(host->base + MIO_EMM_DMA(host));
429 	emm_dma |= FIELD_PREP(MIO_EMM_DMA_VAL, 1) |
430 		   FIELD_PREP(MIO_EMM_DMA_DAT_NULL, 1);
431 	set_bus_id(&emm_dma, get_bus_id(rsp_sts));
432 	writeq(emm_dma, host->base + MIO_EMM_DMA(host));
433 }
434 
cvm_mmc_interrupt(int irq,void * dev_id)435 irqreturn_t cvm_mmc_interrupt(int irq, void *dev_id)
436 {
437 	struct cvm_mmc_host *host = dev_id;
438 	struct mmc_request *req;
439 	u64 emm_int, rsp_sts;
440 	bool host_done;
441 
442 	if (host->need_irq_handler_lock)
443 		spin_lock(&host->irq_handler_lock);
444 	else
445 		__acquire(&host->irq_handler_lock);
446 
447 	/* Clear interrupt bits (write 1 clears ). */
448 	emm_int = readq(host->base + MIO_EMM_INT(host));
449 	writeq(emm_int, host->base + MIO_EMM_INT(host));
450 
451 	if (emm_int & MIO_EMM_INT_SWITCH_ERR)
452 		check_switch_errors(host);
453 
454 	req = host->current_req;
455 	if (!req)
456 		goto out;
457 
458 	rsp_sts = readq(host->base + MIO_EMM_RSP_STS(host));
459 	/*
460 	 * dma_val set means DMA is still in progress. Don't touch
461 	 * the request and wait for the interrupt indicating that
462 	 * the DMA is finished.
463 	 */
464 	if ((rsp_sts & MIO_EMM_RSP_STS_DMA_VAL) && host->dma_active)
465 		goto out;
466 
467 	if (!host->dma_active && req->data &&
468 	    (emm_int & MIO_EMM_INT_BUF_DONE)) {
469 		unsigned int type = (rsp_sts >> 7) & 3;
470 
471 		if (type == 1)
472 			do_read(host, req, rsp_sts & MIO_EMM_RSP_STS_DBUF);
473 		else if (type == 2)
474 			do_write(req);
475 	}
476 
477 	host_done = emm_int & MIO_EMM_INT_CMD_DONE ||
478 		    emm_int & MIO_EMM_INT_DMA_DONE ||
479 		    emm_int & MIO_EMM_INT_CMD_ERR  ||
480 		    emm_int & MIO_EMM_INT_DMA_ERR;
481 
482 	if (!(host_done && req->done))
483 		goto no_req_done;
484 
485 	req->cmd->error = check_status(rsp_sts);
486 
487 	if (host->dma_active && req->data)
488 		if (!finish_dma(host, req->data))
489 			goto no_req_done;
490 
491 	set_cmd_response(host, req, rsp_sts);
492 	if ((emm_int & MIO_EMM_INT_DMA_ERR) &&
493 	    (rsp_sts & MIO_EMM_RSP_STS_DMA_PEND))
494 		cleanup_dma(host, rsp_sts);
495 
496 	host->current_req = NULL;
497 	req->done(req);
498 
499 no_req_done:
500 	if (host->dmar_fixup_done)
501 		host->dmar_fixup_done(host);
502 	if (host_done)
503 		host->release_bus(host);
504 out:
505 	if (host->need_irq_handler_lock)
506 		spin_unlock(&host->irq_handler_lock);
507 	else
508 		__release(&host->irq_handler_lock);
509 	return IRQ_RETVAL(emm_int != 0);
510 }
511 
512 /*
513  * Program DMA_CFG and if needed DMA_ADR.
514  * Returns 0 on error, DMA address otherwise.
515  */
prepare_dma_single(struct cvm_mmc_host * host,struct mmc_data * data)516 static u64 prepare_dma_single(struct cvm_mmc_host *host, struct mmc_data *data)
517 {
518 	u64 dma_cfg, addr;
519 	int count, rw;
520 
521 	count = dma_map_sg(host->dev, data->sg, data->sg_len,
522 			   get_dma_dir(data));
523 	if (!count)
524 		return 0;
525 
526 	rw = (data->flags & MMC_DATA_WRITE) ? 1 : 0;
527 	dma_cfg = FIELD_PREP(MIO_EMM_DMA_CFG_EN, 1) |
528 		  FIELD_PREP(MIO_EMM_DMA_CFG_RW, rw);
529 #ifdef __LITTLE_ENDIAN
530 	dma_cfg |= FIELD_PREP(MIO_EMM_DMA_CFG_ENDIAN, 1);
531 #endif
532 	dma_cfg |= FIELD_PREP(MIO_EMM_DMA_CFG_SIZE,
533 			      (sg_dma_len(&data->sg[0]) / 8) - 1);
534 
535 	addr = sg_dma_address(&data->sg[0]);
536 	if (!host->big_dma_addr)
537 		dma_cfg |= FIELD_PREP(MIO_EMM_DMA_CFG_ADR, addr);
538 	writeq(dma_cfg, host->dma_base + MIO_EMM_DMA_CFG(host));
539 
540 	pr_debug("[%s] sg_dma_len: %u  total sg_elem: %d\n",
541 		 (rw) ? "W" : "R", sg_dma_len(&data->sg[0]), count);
542 
543 	if (host->big_dma_addr)
544 		writeq(addr, host->dma_base + MIO_EMM_DMA_ADR(host));
545 	return addr;
546 }
547 
548 /*
549  * Queue complete sg list into the FIFO.
550  * Returns 0 on error, 1 otherwise.
551  */
prepare_dma_sg(struct cvm_mmc_host * host,struct mmc_data * data)552 static u64 prepare_dma_sg(struct cvm_mmc_host *host, struct mmc_data *data)
553 {
554 	struct scatterlist *sg;
555 	u64 fifo_cmd, addr;
556 	int count, i, rw;
557 
558 	count = dma_map_sg(host->dev, data->sg, data->sg_len,
559 			   get_dma_dir(data));
560 	if (!count)
561 		return 0;
562 	if (count > 16)
563 		goto error;
564 
565 	/* Enable FIFO by removing CLR bit */
566 	writeq(0, host->dma_base + MIO_EMM_DMA_FIFO_CFG(host));
567 
568 	for_each_sg(data->sg, sg, count, i) {
569 		/* Program DMA address */
570 		addr = sg_dma_address(sg);
571 		if (addr & 7)
572 			goto error;
573 		writeq(addr, host->dma_base + MIO_EMM_DMA_FIFO_ADR(host));
574 
575 		/*
576 		 * If we have scatter-gather support we also have an extra
577 		 * register for the DMA addr, so no need to check
578 		 * host->big_dma_addr here.
579 		 */
580 		rw = (data->flags & MMC_DATA_WRITE) ? 1 : 0;
581 		fifo_cmd = FIELD_PREP(MIO_EMM_DMA_FIFO_CMD_RW, rw);
582 
583 		/* enable interrupts on the last element */
584 		fifo_cmd |= FIELD_PREP(MIO_EMM_DMA_FIFO_CMD_INTDIS,
585 				       (i + 1 == count) ? 0 : 1);
586 
587 #ifdef __LITTLE_ENDIAN
588 		fifo_cmd |= FIELD_PREP(MIO_EMM_DMA_FIFO_CMD_ENDIAN, 1);
589 #endif
590 		fifo_cmd |= FIELD_PREP(MIO_EMM_DMA_FIFO_CMD_SIZE,
591 				       sg_dma_len(sg) / 8 - 1);
592 		/*
593 		 * The write copies the address and the command to the FIFO
594 		 * and increments the FIFO's COUNT field.
595 		 */
596 		writeq(fifo_cmd, host->dma_base + MIO_EMM_DMA_FIFO_CMD(host));
597 		pr_debug("[%s] sg_dma_len: %u  sg_elem: %d/%d\n",
598 			 (rw) ? "W" : "R", sg_dma_len(sg), i, count);
599 	}
600 
601 	/*
602 	 * In difference to prepare_dma_single we don't return the
603 	 * address here, as it would not make sense for scatter-gather.
604 	 * The dma fixup is only required on models that don't support
605 	 * scatter-gather, so that is not a problem.
606 	 */
607 	return 1;
608 
609 error:
610 	WARN_ON_ONCE(1);
611 	dma_unmap_sg(host->dev, data->sg, data->sg_len, get_dma_dir(data));
612 	/* Disable FIFO */
613 	writeq(BIT_ULL(16), host->dma_base + MIO_EMM_DMA_FIFO_CFG(host));
614 	return 0;
615 }
616 
prepare_dma(struct cvm_mmc_host * host,struct mmc_data * data)617 static u64 prepare_dma(struct cvm_mmc_host *host, struct mmc_data *data)
618 {
619 	if (host->use_sg && data->sg_len > 1)
620 		return prepare_dma_sg(host, data);
621 	else
622 		return prepare_dma_single(host, data);
623 }
624 
prepare_ext_dma(struct mmc_host * mmc,struct mmc_request * mrq)625 static u64 prepare_ext_dma(struct mmc_host *mmc, struct mmc_request *mrq)
626 {
627 	struct cvm_mmc_slot *slot = mmc_priv(mmc);
628 	u64 emm_dma;
629 
630 	emm_dma = FIELD_PREP(MIO_EMM_DMA_VAL, 1) |
631 		  FIELD_PREP(MIO_EMM_DMA_SECTOR,
632 			     mmc_card_is_blockaddr(mmc->card) ? 1 : 0) |
633 		  FIELD_PREP(MIO_EMM_DMA_RW,
634 			     (mrq->data->flags & MMC_DATA_WRITE) ? 1 : 0) |
635 		  FIELD_PREP(MIO_EMM_DMA_BLOCK_CNT, mrq->data->blocks) |
636 		  FIELD_PREP(MIO_EMM_DMA_CARD_ADDR, mrq->cmd->arg);
637 	set_bus_id(&emm_dma, slot->bus_id);
638 
639 	if (mmc_card_mmc(mmc->card) || (mmc_card_sd(mmc->card) &&
640 	    (mmc->card->scr.cmds & SD_SCR_CMD23_SUPPORT)))
641 		emm_dma |= FIELD_PREP(MIO_EMM_DMA_MULTI, 1);
642 
643 	pr_debug("[%s] blocks: %u  multi: %d\n",
644 		(emm_dma & MIO_EMM_DMA_RW) ? "W" : "R",
645 		 mrq->data->blocks, (emm_dma & MIO_EMM_DMA_MULTI) ? 1 : 0);
646 	return emm_dma;
647 }
648 
cvm_mmc_dma_request(struct mmc_host * mmc,struct mmc_request * mrq)649 static void cvm_mmc_dma_request(struct mmc_host *mmc,
650 				struct mmc_request *mrq)
651 {
652 	struct cvm_mmc_slot *slot = mmc_priv(mmc);
653 	struct cvm_mmc_host *host = slot->host;
654 	struct mmc_data *data;
655 	u64 emm_dma, addr;
656 
657 	if (!mrq->data || !mrq->data->sg || !mrq->data->sg_len ||
658 	    !mrq->stop || mrq->stop->opcode != MMC_STOP_TRANSMISSION) {
659 		dev_err(&mmc->card->dev, "Error: %s no data\n", __func__);
660 		goto error;
661 	}
662 
663 	cvm_mmc_switch_to(slot);
664 
665 	data = mrq->data;
666 	pr_debug("DMA request  blocks: %d  block_size: %d  total_size: %d\n",
667 		 data->blocks, data->blksz, data->blocks * data->blksz);
668 	if (data->timeout_ns)
669 		set_wdog(slot, data->timeout_ns);
670 
671 	WARN_ON(host->current_req);
672 	host->current_req = mrq;
673 
674 	emm_dma = prepare_ext_dma(mmc, mrq);
675 	addr = prepare_dma(host, data);
676 	if (!addr) {
677 		dev_err(host->dev, "prepare_dma failed\n");
678 		goto error;
679 	}
680 
681 	host->dma_active = true;
682 	host->int_enable(host, MIO_EMM_INT_CMD_ERR | MIO_EMM_INT_DMA_DONE |
683 			 MIO_EMM_INT_DMA_ERR);
684 
685 	if (host->dmar_fixup)
686 		host->dmar_fixup(host, mrq->cmd, data, addr);
687 
688 	/*
689 	 * If we have a valid SD card in the slot, we set the response
690 	 * bit mask to check for CRC errors and timeouts only.
691 	 * Otherwise, use the default power reset value.
692 	 */
693 	if (mmc_card_sd(mmc->card))
694 		writeq(0x00b00000ull, host->base + MIO_EMM_STS_MASK(host));
695 	else
696 		writeq(0xe4390080ull, host->base + MIO_EMM_STS_MASK(host));
697 	writeq(emm_dma, host->base + MIO_EMM_DMA(host));
698 	return;
699 
700 error:
701 	mrq->cmd->error = -EINVAL;
702 	if (mrq->done)
703 		mrq->done(mrq);
704 	host->release_bus(host);
705 }
706 
do_read_request(struct cvm_mmc_host * host,struct mmc_request * mrq)707 static void do_read_request(struct cvm_mmc_host *host, struct mmc_request *mrq)
708 {
709 	sg_miter_start(&host->smi, mrq->data->sg, mrq->data->sg_len,
710 		       SG_MITER_ATOMIC | SG_MITER_TO_SG);
711 }
712 
do_write_request(struct cvm_mmc_host * host,struct mmc_request * mrq)713 static void do_write_request(struct cvm_mmc_host *host, struct mmc_request *mrq)
714 {
715 	unsigned int data_len = mrq->data->blocks * mrq->data->blksz;
716 	struct sg_mapping_iter *smi = &host->smi;
717 	unsigned int bytes_xfered;
718 	int shift = 56;
719 	u64 dat = 0;
720 
721 	/* Copy data to the xmit buffer before issuing the command. */
722 	sg_miter_start(smi, mrq->data->sg, mrq->data->sg_len, SG_MITER_FROM_SG);
723 
724 	/* Auto inc from offset zero, dbuf zero */
725 	writeq(0x10000ull, host->base + MIO_EMM_BUF_IDX(host));
726 
727 	for (bytes_xfered = 0; bytes_xfered < data_len;) {
728 		if (smi->consumed >= smi->length) {
729 			if (!sg_miter_next(smi))
730 				break;
731 			smi->consumed = 0;
732 		}
733 
734 		while (smi->consumed < smi->length && shift >= 0) {
735 			dat |= (u64)((u8 *)smi->addr)[smi->consumed] << shift;
736 			bytes_xfered++;
737 			smi->consumed++;
738 			shift -= 8;
739 		}
740 
741 		if (shift < 0) {
742 			writeq(dat, host->base + MIO_EMM_BUF_DAT(host));
743 			shift = 56;
744 			dat = 0;
745 		}
746 	}
747 	sg_miter_stop(smi);
748 }
749 
cvm_mmc_request(struct mmc_host * mmc,struct mmc_request * mrq)750 static void cvm_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
751 {
752 	struct cvm_mmc_slot *slot = mmc_priv(mmc);
753 	struct cvm_mmc_host *host = slot->host;
754 	struct mmc_command *cmd = mrq->cmd;
755 	struct cvm_mmc_cr_mods mods;
756 	u64 emm_cmd, rsp_sts;
757 	int retries = 100;
758 
759 	/*
760 	 * Note about locking:
761 	 * All MMC devices share the same bus and controller. Allow only a
762 	 * single user of the bootbus/MMC bus at a time. The lock is acquired
763 	 * on all entry points from the MMC layer.
764 	 *
765 	 * For requests the lock is only released after the completion
766 	 * interrupt!
767 	 */
768 	host->acquire_bus(host);
769 
770 	if (cmd->opcode == MMC_READ_MULTIPLE_BLOCK ||
771 	    cmd->opcode == MMC_WRITE_MULTIPLE_BLOCK)
772 		return cvm_mmc_dma_request(mmc, mrq);
773 
774 	cvm_mmc_switch_to(slot);
775 
776 	mods = cvm_mmc_get_cr_mods(cmd);
777 
778 	WARN_ON(host->current_req);
779 	host->current_req = mrq;
780 
781 	if (cmd->data) {
782 		if (cmd->data->flags & MMC_DATA_READ)
783 			do_read_request(host, mrq);
784 		else
785 			do_write_request(host, mrq);
786 
787 		if (cmd->data->timeout_ns)
788 			set_wdog(slot, cmd->data->timeout_ns);
789 	} else
790 		set_wdog(slot, 0);
791 
792 	host->dma_active = false;
793 	host->int_enable(host, MIO_EMM_INT_CMD_DONE | MIO_EMM_INT_CMD_ERR);
794 
795 	emm_cmd = FIELD_PREP(MIO_EMM_CMD_VAL, 1) |
796 		  FIELD_PREP(MIO_EMM_CMD_CTYPE_XOR, mods.ctype_xor) |
797 		  FIELD_PREP(MIO_EMM_CMD_RTYPE_XOR, mods.rtype_xor) |
798 		  FIELD_PREP(MIO_EMM_CMD_IDX, cmd->opcode) |
799 		  FIELD_PREP(MIO_EMM_CMD_ARG, cmd->arg);
800 	set_bus_id(&emm_cmd, slot->bus_id);
801 	if (cmd->data && mmc_cmd_type(cmd) == MMC_CMD_ADTC)
802 		emm_cmd |= FIELD_PREP(MIO_EMM_CMD_OFFSET,
803 				64 - ((cmd->data->blocks * cmd->data->blksz) / 8));
804 
805 	writeq(0, host->base + MIO_EMM_STS_MASK(host));
806 
807 retry:
808 	rsp_sts = readq(host->base + MIO_EMM_RSP_STS(host));
809 	if (rsp_sts & MIO_EMM_RSP_STS_DMA_VAL ||
810 	    rsp_sts & MIO_EMM_RSP_STS_CMD_VAL ||
811 	    rsp_sts & MIO_EMM_RSP_STS_SWITCH_VAL ||
812 	    rsp_sts & MIO_EMM_RSP_STS_DMA_PEND) {
813 		udelay(10);
814 		if (--retries)
815 			goto retry;
816 	}
817 	if (!retries)
818 		dev_err(host->dev, "Bad status: %llx before command write\n", rsp_sts);
819 	writeq(emm_cmd, host->base + MIO_EMM_CMD(host));
820 }
821 
cvm_mmc_set_ios(struct mmc_host * mmc,struct mmc_ios * ios)822 static void cvm_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
823 {
824 	struct cvm_mmc_slot *slot = mmc_priv(mmc);
825 	struct cvm_mmc_host *host = slot->host;
826 	int clk_period = 0, power_class = 10, bus_width = 0;
827 	u64 clock, emm_switch;
828 
829 	host->acquire_bus(host);
830 	cvm_mmc_switch_to(slot);
831 
832 	/* Set the power state */
833 	switch (ios->power_mode) {
834 	case MMC_POWER_ON:
835 		break;
836 
837 	case MMC_POWER_OFF:
838 		cvm_mmc_reset_bus(slot);
839 		if (host->global_pwr_gpiod)
840 			host->set_shared_power(host, 0);
841 		else if (!IS_ERR(mmc->supply.vmmc))
842 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
843 		break;
844 
845 	case MMC_POWER_UP:
846 		if (host->global_pwr_gpiod)
847 			host->set_shared_power(host, 1);
848 		else if (!IS_ERR(mmc->supply.vmmc))
849 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
850 		break;
851 	}
852 
853 	/* Convert bus width to HW definition */
854 	switch (ios->bus_width) {
855 	case MMC_BUS_WIDTH_8:
856 		bus_width = 2;
857 		break;
858 	case MMC_BUS_WIDTH_4:
859 		bus_width = 1;
860 		break;
861 	case MMC_BUS_WIDTH_1:
862 		bus_width = 0;
863 		break;
864 	}
865 
866 	/* DDR is available for 4/8 bit bus width */
867 	if (ios->bus_width && ios->timing == MMC_TIMING_MMC_DDR52)
868 		bus_width |= 4;
869 
870 	/* Change the clock frequency. */
871 	clock = ios->clock;
872 	if (clock > 52000000)
873 		clock = 52000000;
874 	slot->clock = clock;
875 
876 	if (clock)
877 		clk_period = (host->sys_freq + clock - 1) / (2 * clock);
878 
879 	emm_switch = FIELD_PREP(MIO_EMM_SWITCH_HS_TIMING,
880 				(ios->timing == MMC_TIMING_MMC_HS)) |
881 		     FIELD_PREP(MIO_EMM_SWITCH_BUS_WIDTH, bus_width) |
882 		     FIELD_PREP(MIO_EMM_SWITCH_POWER_CLASS, power_class) |
883 		     FIELD_PREP(MIO_EMM_SWITCH_CLK_HI, clk_period) |
884 		     FIELD_PREP(MIO_EMM_SWITCH_CLK_LO, clk_period);
885 	set_bus_id(&emm_switch, slot->bus_id);
886 
887 	if (!switch_val_changed(slot, emm_switch))
888 		goto out;
889 
890 	set_wdog(slot, 0);
891 	do_switch(host, emm_switch);
892 	slot->cached_switch = emm_switch;
893 out:
894 	host->release_bus(host);
895 }
896 
897 static const struct mmc_host_ops cvm_mmc_ops = {
898 	.request        = cvm_mmc_request,
899 	.set_ios        = cvm_mmc_set_ios,
900 	.get_ro		= mmc_gpio_get_ro,
901 	.get_cd		= mmc_gpio_get_cd,
902 };
903 
cvm_mmc_set_clock(struct cvm_mmc_slot * slot,unsigned int clock)904 static void cvm_mmc_set_clock(struct cvm_mmc_slot *slot, unsigned int clock)
905 {
906 	struct mmc_host *mmc = slot->mmc;
907 
908 	clock = min(clock, mmc->f_max);
909 	clock = max(clock, mmc->f_min);
910 	slot->clock = clock;
911 }
912 
cvm_mmc_init_lowlevel(struct cvm_mmc_slot * slot)913 static int cvm_mmc_init_lowlevel(struct cvm_mmc_slot *slot)
914 {
915 	struct cvm_mmc_host *host = slot->host;
916 	u64 emm_switch;
917 
918 	/* Enable this bus slot. */
919 	host->emm_cfg |= (1ull << slot->bus_id);
920 	writeq(host->emm_cfg, slot->host->base + MIO_EMM_CFG(host));
921 	udelay(10);
922 
923 	/* Program initial clock speed and power. */
924 	cvm_mmc_set_clock(slot, slot->mmc->f_min);
925 	emm_switch = FIELD_PREP(MIO_EMM_SWITCH_POWER_CLASS, 10);
926 	emm_switch |= FIELD_PREP(MIO_EMM_SWITCH_CLK_HI,
927 				 (host->sys_freq / slot->clock) / 2);
928 	emm_switch |= FIELD_PREP(MIO_EMM_SWITCH_CLK_LO,
929 				 (host->sys_freq / slot->clock) / 2);
930 
931 	/* Make the changes take effect on this bus slot. */
932 	set_bus_id(&emm_switch, slot->bus_id);
933 	do_switch(host, emm_switch);
934 
935 	slot->cached_switch = emm_switch;
936 
937 	/*
938 	 * Set watchdog timeout value and default reset value
939 	 * for the mask register. Finally, set the CARD_RCA
940 	 * bit so that we can get the card address relative
941 	 * to the CMD register for CMD7 transactions.
942 	 */
943 	set_wdog(slot, 0);
944 	writeq(0xe4390080ull, host->base + MIO_EMM_STS_MASK(host));
945 	writeq(1, host->base + MIO_EMM_RCA(host));
946 	return 0;
947 }
948 
cvm_mmc_of_parse(struct device * dev,struct cvm_mmc_slot * slot)949 static int cvm_mmc_of_parse(struct device *dev, struct cvm_mmc_slot *slot)
950 {
951 	u32 id, cmd_skew = 0, dat_skew = 0, bus_width = 0;
952 	struct device_node *node = dev->of_node;
953 	struct mmc_host *mmc = slot->mmc;
954 	u64 clock_period;
955 	int ret;
956 
957 	ret = of_property_read_u32(node, "reg", &id);
958 	if (ret) {
959 		dev_err(dev, "Missing or invalid reg property on %pOF\n", node);
960 		return ret;
961 	}
962 
963 	if (id >= CAVIUM_MAX_MMC || slot->host->slot[id]) {
964 		dev_err(dev, "Invalid reg property on %pOF\n", node);
965 		return -EINVAL;
966 	}
967 
968 	ret = mmc_regulator_get_supply(mmc);
969 	if (ret)
970 		return ret;
971 	/*
972 	 * Legacy Octeon firmware has no regulator entry, fall-back to
973 	 * a hard-coded voltage to get a sane OCR.
974 	 */
975 	if (IS_ERR(mmc->supply.vmmc))
976 		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
977 
978 	/* Common MMC bindings */
979 	ret = mmc_of_parse(mmc);
980 	if (ret)
981 		return ret;
982 
983 	/* Set bus width */
984 	if (!(mmc->caps & (MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA))) {
985 		of_property_read_u32(node, "cavium,bus-max-width", &bus_width);
986 		if (bus_width == 8)
987 			mmc->caps |= MMC_CAP_8_BIT_DATA | MMC_CAP_4_BIT_DATA;
988 		else if (bus_width == 4)
989 			mmc->caps |= MMC_CAP_4_BIT_DATA;
990 	}
991 
992 	/* Set maximum and minimum frequency */
993 	if (!mmc->f_max)
994 		of_property_read_u32(node, "spi-max-frequency", &mmc->f_max);
995 	if (!mmc->f_max || mmc->f_max > 52000000)
996 		mmc->f_max = 52000000;
997 	mmc->f_min = 400000;
998 
999 	/* Sampling register settings, period in picoseconds */
1000 	clock_period = 1000000000000ull / slot->host->sys_freq;
1001 	of_property_read_u32(node, "cavium,cmd-clk-skew", &cmd_skew);
1002 	of_property_read_u32(node, "cavium,dat-clk-skew", &dat_skew);
1003 	slot->cmd_cnt = (cmd_skew + clock_period / 2) / clock_period;
1004 	slot->dat_cnt = (dat_skew + clock_period / 2) / clock_period;
1005 
1006 	return id;
1007 }
1008 
cvm_mmc_of_slot_probe(struct device * dev,struct cvm_mmc_host * host)1009 int cvm_mmc_of_slot_probe(struct device *dev, struct cvm_mmc_host *host)
1010 {
1011 	struct cvm_mmc_slot *slot;
1012 	struct mmc_host *mmc;
1013 	int ret, id;
1014 
1015 	mmc = mmc_alloc_host(sizeof(struct cvm_mmc_slot), dev);
1016 	if (!mmc)
1017 		return -ENOMEM;
1018 
1019 	slot = mmc_priv(mmc);
1020 	slot->mmc = mmc;
1021 	slot->host = host;
1022 
1023 	ret = cvm_mmc_of_parse(dev, slot);
1024 	if (ret < 0)
1025 		goto error;
1026 	id = ret;
1027 
1028 	/* Set up host parameters */
1029 	mmc->ops = &cvm_mmc_ops;
1030 
1031 	/*
1032 	 * We only have a 3.3v supply, we cannot support any
1033 	 * of the UHS modes. We do support the high speed DDR
1034 	 * modes up to 52MHz.
1035 	 *
1036 	 * Disable bounce buffers for max_segs = 1
1037 	 */
1038 	mmc->caps |= MMC_CAP_MMC_HIGHSPEED | MMC_CAP_SD_HIGHSPEED |
1039 		     MMC_CAP_CMD23 | MMC_CAP_POWER_OFF_CARD | MMC_CAP_3_3V_DDR;
1040 
1041 	if (host->use_sg)
1042 		mmc->max_segs = 16;
1043 	else
1044 		mmc->max_segs = 1;
1045 
1046 	/* DMA size field can address up to 8 MB */
1047 	mmc->max_seg_size = min_t(unsigned int, 8 * 1024 * 1024,
1048 				  dma_get_max_seg_size(host->dev));
1049 	mmc->max_req_size = mmc->max_seg_size;
1050 	/* External DMA is in 512 byte blocks */
1051 	mmc->max_blk_size = 512;
1052 	/* DMA block count field is 15 bits */
1053 	mmc->max_blk_count = 32767;
1054 
1055 	slot->clock = mmc->f_min;
1056 	slot->bus_id = id;
1057 	slot->cached_rca = 1;
1058 
1059 	host->acquire_bus(host);
1060 	host->slot[id] = slot;
1061 	cvm_mmc_switch_to(slot);
1062 	cvm_mmc_init_lowlevel(slot);
1063 	host->release_bus(host);
1064 
1065 	ret = mmc_add_host(mmc);
1066 	if (ret) {
1067 		dev_err(dev, "mmc_add_host() returned %d\n", ret);
1068 		slot->host->slot[id] = NULL;
1069 		goto error;
1070 	}
1071 	return 0;
1072 
1073 error:
1074 	mmc_free_host(slot->mmc);
1075 	return ret;
1076 }
1077 
cvm_mmc_of_slot_remove(struct cvm_mmc_slot * slot)1078 int cvm_mmc_of_slot_remove(struct cvm_mmc_slot *slot)
1079 {
1080 	mmc_remove_host(slot->mmc);
1081 	slot->host->slot[slot->bus_id] = NULL;
1082 	mmc_free_host(slot->mmc);
1083 	return 0;
1084 }
1085