xref: /linux/drivers/mmc/host/meson-gx-mmc.c (revision 79997eda0d31bc68203c95ecb978773ee6ce7a1f)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Amlogic SD/eMMC driver for the GX/S905 family SoCs
4  *
5  * Copyright (c) 2016 BayLibre, SAS.
6  * Author: Kevin Hilman <khilman@baylibre.com>
7  */
8 #include <linux/kernel.h>
9 #include <linux/module.h>
10 #include <linux/init.h>
11 #include <linux/delay.h>
12 #include <linux/device.h>
13 #include <linux/iopoll.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/ioport.h>
17 #include <linux/dma-mapping.h>
18 #include <linux/mmc/host.h>
19 #include <linux/mmc/mmc.h>
20 #include <linux/mmc/sdio.h>
21 #include <linux/mmc/slot-gpio.h>
22 #include <linux/io.h>
23 #include <linux/clk.h>
24 #include <linux/clk-provider.h>
25 #include <linux/regulator/consumer.h>
26 #include <linux/reset.h>
27 #include <linux/interrupt.h>
28 #include <linux/bitfield.h>
29 #include <linux/pinctrl/consumer.h>
30 
31 #define DRIVER_NAME "meson-gx-mmc"
32 
33 #define SD_EMMC_CLOCK 0x0
34 #define   CLK_DIV_MASK GENMASK(5, 0)
35 #define   CLK_SRC_MASK GENMASK(7, 6)
36 #define   CLK_CORE_PHASE_MASK GENMASK(9, 8)
37 #define   CLK_TX_PHASE_MASK GENMASK(11, 10)
38 #define   CLK_RX_PHASE_MASK GENMASK(13, 12)
39 #define   CLK_PHASE_0 0
40 #define   CLK_PHASE_180 2
41 #define   CLK_V2_TX_DELAY_MASK GENMASK(19, 16)
42 #define   CLK_V2_RX_DELAY_MASK GENMASK(23, 20)
43 #define   CLK_V2_ALWAYS_ON BIT(24)
44 #define   CLK_V2_IRQ_SDIO_SLEEP BIT(25)
45 
46 #define   CLK_V3_TX_DELAY_MASK GENMASK(21, 16)
47 #define   CLK_V3_RX_DELAY_MASK GENMASK(27, 22)
48 #define   CLK_V3_ALWAYS_ON BIT(28)
49 #define   CLK_V3_IRQ_SDIO_SLEEP BIT(29)
50 
51 #define   CLK_TX_DELAY_MASK(h)		(h->data->tx_delay_mask)
52 #define   CLK_RX_DELAY_MASK(h)		(h->data->rx_delay_mask)
53 #define   CLK_ALWAYS_ON(h)		(h->data->always_on)
54 #define   CLK_IRQ_SDIO_SLEEP(h)		(h->data->irq_sdio_sleep)
55 
56 #define SD_EMMC_DELAY 0x4
57 #define SD_EMMC_ADJUST 0x8
58 #define   ADJUST_ADJ_DELAY_MASK GENMASK(21, 16)
59 #define   ADJUST_DS_EN BIT(15)
60 #define   ADJUST_ADJ_EN BIT(13)
61 
62 #define SD_EMMC_DELAY1 0x4
63 #define SD_EMMC_DELAY2 0x8
64 #define SD_EMMC_V3_ADJUST 0xc
65 
66 #define SD_EMMC_CALOUT 0x10
67 #define SD_EMMC_START 0x40
68 #define   START_DESC_INIT BIT(0)
69 #define   START_DESC_BUSY BIT(1)
70 #define   START_DESC_ADDR_MASK GENMASK(31, 2)
71 
72 #define SD_EMMC_CFG 0x44
73 #define   CFG_BUS_WIDTH_MASK GENMASK(1, 0)
74 #define   CFG_BUS_WIDTH_1 0x0
75 #define   CFG_BUS_WIDTH_4 0x1
76 #define   CFG_BUS_WIDTH_8 0x2
77 #define   CFG_DDR BIT(2)
78 #define   CFG_BLK_LEN_MASK GENMASK(7, 4)
79 #define   CFG_RESP_TIMEOUT_MASK GENMASK(11, 8)
80 #define   CFG_RC_CC_MASK GENMASK(15, 12)
81 #define   CFG_STOP_CLOCK BIT(22)
82 #define   CFG_CLK_ALWAYS_ON BIT(18)
83 #define   CFG_CHK_DS BIT(20)
84 #define   CFG_AUTO_CLK BIT(23)
85 #define   CFG_ERR_ABORT BIT(27)
86 
87 #define SD_EMMC_STATUS 0x48
88 #define   STATUS_BUSY BIT(31)
89 #define   STATUS_DESC_BUSY BIT(30)
90 #define   STATUS_DATI GENMASK(23, 16)
91 
92 #define SD_EMMC_IRQ_EN 0x4c
93 #define   IRQ_RXD_ERR_MASK GENMASK(7, 0)
94 #define   IRQ_TXD_ERR BIT(8)
95 #define   IRQ_DESC_ERR BIT(9)
96 #define   IRQ_RESP_ERR BIT(10)
97 #define   IRQ_CRC_ERR \
98 	(IRQ_RXD_ERR_MASK | IRQ_TXD_ERR | IRQ_DESC_ERR | IRQ_RESP_ERR)
99 #define   IRQ_RESP_TIMEOUT BIT(11)
100 #define   IRQ_DESC_TIMEOUT BIT(12)
101 #define   IRQ_TIMEOUTS \
102 	(IRQ_RESP_TIMEOUT | IRQ_DESC_TIMEOUT)
103 #define   IRQ_END_OF_CHAIN BIT(13)
104 #define   IRQ_RESP_STATUS BIT(14)
105 #define   IRQ_SDIO BIT(15)
106 #define   IRQ_EN_MASK \
107 	(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN)
108 
109 #define SD_EMMC_CMD_CFG 0x50
110 #define SD_EMMC_CMD_ARG 0x54
111 #define SD_EMMC_CMD_DAT 0x58
112 #define SD_EMMC_CMD_RSP 0x5c
113 #define SD_EMMC_CMD_RSP1 0x60
114 #define SD_EMMC_CMD_RSP2 0x64
115 #define SD_EMMC_CMD_RSP3 0x68
116 
117 #define SD_EMMC_RXD 0x94
118 #define SD_EMMC_TXD 0x94
119 #define SD_EMMC_LAST_REG SD_EMMC_TXD
120 
121 #define SD_EMMC_SRAM_DATA_BUF_LEN 1536
122 #define SD_EMMC_SRAM_DATA_BUF_OFF 0x200
123 
124 #define SD_EMMC_CFG_BLK_SIZE 512 /* internal buffer max: 512 bytes */
125 #define SD_EMMC_CFG_RESP_TIMEOUT 256 /* in clock cycles */
126 #define SD_EMMC_CMD_TIMEOUT 1024 /* in ms */
127 #define SD_EMMC_CMD_TIMEOUT_DATA 4096 /* in ms */
128 #define SD_EMMC_CFG_CMD_GAP 16 /* in clock cycles */
129 #define SD_EMMC_DESC_BUF_LEN PAGE_SIZE
130 
131 #define SD_EMMC_PRE_REQ_DONE BIT(0)
132 #define SD_EMMC_DESC_CHAIN_MODE BIT(1)
133 
134 #define MUX_CLK_NUM_PARENTS 2
135 
136 struct meson_mmc_data {
137 	unsigned int tx_delay_mask;
138 	unsigned int rx_delay_mask;
139 	unsigned int always_on;
140 	unsigned int adjust;
141 	unsigned int irq_sdio_sleep;
142 };
143 
144 struct sd_emmc_desc {
145 	u32 cmd_cfg;
146 	u32 cmd_arg;
147 	u32 cmd_data;
148 	u32 cmd_resp;
149 };
150 
151 struct meson_host {
152 	struct	device		*dev;
153 	const struct meson_mmc_data *data;
154 	struct	mmc_host	*mmc;
155 	struct	mmc_command	*cmd;
156 
157 	void __iomem *regs;
158 	struct clk *mux_clk;
159 	struct clk *mmc_clk;
160 	unsigned long req_rate;
161 	bool ddr;
162 
163 	bool dram_access_quirk;
164 
165 	struct pinctrl *pinctrl;
166 	struct pinctrl_state *pins_clk_gate;
167 
168 	unsigned int bounce_buf_size;
169 	void *bounce_buf;
170 	void __iomem *bounce_iomem_buf;
171 	dma_addr_t bounce_dma_addr;
172 	struct sd_emmc_desc *descs;
173 	dma_addr_t descs_dma_addr;
174 
175 	int irq;
176 
177 	bool needs_pre_post_req;
178 
179 	spinlock_t lock;
180 };
181 
182 #define CMD_CFG_LENGTH_MASK GENMASK(8, 0)
183 #define CMD_CFG_BLOCK_MODE BIT(9)
184 #define CMD_CFG_R1B BIT(10)
185 #define CMD_CFG_END_OF_CHAIN BIT(11)
186 #define CMD_CFG_TIMEOUT_MASK GENMASK(15, 12)
187 #define CMD_CFG_NO_RESP BIT(16)
188 #define CMD_CFG_NO_CMD BIT(17)
189 #define CMD_CFG_DATA_IO BIT(18)
190 #define CMD_CFG_DATA_WR BIT(19)
191 #define CMD_CFG_RESP_NOCRC BIT(20)
192 #define CMD_CFG_RESP_128 BIT(21)
193 #define CMD_CFG_RESP_NUM BIT(22)
194 #define CMD_CFG_DATA_NUM BIT(23)
195 #define CMD_CFG_CMD_INDEX_MASK GENMASK(29, 24)
196 #define CMD_CFG_ERROR BIT(30)
197 #define CMD_CFG_OWNER BIT(31)
198 
199 #define CMD_DATA_MASK GENMASK(31, 2)
200 #define CMD_DATA_BIG_ENDIAN BIT(1)
201 #define CMD_DATA_SRAM BIT(0)
202 #define CMD_RESP_MASK GENMASK(31, 1)
203 #define CMD_RESP_SRAM BIT(0)
204 
205 static unsigned int meson_mmc_get_timeout_msecs(struct mmc_data *data)
206 {
207 	unsigned int timeout = data->timeout_ns / NSEC_PER_MSEC;
208 
209 	if (!timeout)
210 		return SD_EMMC_CMD_TIMEOUT_DATA;
211 
212 	timeout = roundup_pow_of_two(timeout);
213 
214 	return min(timeout, 32768U); /* max. 2^15 ms */
215 }
216 
217 static struct mmc_command *meson_mmc_get_next_command(struct mmc_command *cmd)
218 {
219 	if (cmd->opcode == MMC_SET_BLOCK_COUNT && !cmd->error)
220 		return cmd->mrq->cmd;
221 	else if (mmc_op_multi(cmd->opcode) &&
222 		 (!cmd->mrq->sbc || cmd->error || cmd->data->error))
223 		return cmd->mrq->stop;
224 	else
225 		return NULL;
226 }
227 
228 static void meson_mmc_get_transfer_mode(struct mmc_host *mmc,
229 					struct mmc_request *mrq)
230 {
231 	struct meson_host *host = mmc_priv(mmc);
232 	struct mmc_data *data = mrq->data;
233 	struct scatterlist *sg;
234 	int i;
235 
236 	/*
237 	 * When Controller DMA cannot directly access DDR memory, disable
238 	 * support for Chain Mode to directly use the internal SRAM using
239 	 * the bounce buffer mode.
240 	 */
241 	if (host->dram_access_quirk)
242 		return;
243 
244 	/* SD_IO_RW_EXTENDED (CMD53) can also use block mode under the hood */
245 	if (data->blocks > 1 || mrq->cmd->opcode == SD_IO_RW_EXTENDED) {
246 		/*
247 		 * In block mode DMA descriptor format, "length" field indicates
248 		 * number of blocks and there is no way to pass DMA size that
249 		 * is not multiple of SDIO block size, making it impossible to
250 		 * tie more than one memory buffer with single SDIO block.
251 		 * Block mode sg buffer size should be aligned with SDIO block
252 		 * size, otherwise chain mode could not be used.
253 		 */
254 		for_each_sg(data->sg, sg, data->sg_len, i) {
255 			if (sg->length % data->blksz) {
256 				dev_warn_once(mmc_dev(mmc),
257 					      "unaligned sg len %u blksize %u, disabling descriptor DMA for transfer\n",
258 					      sg->length, data->blksz);
259 				return;
260 			}
261 		}
262 	}
263 
264 	for_each_sg(data->sg, sg, data->sg_len, i) {
265 		/* check for 8 byte alignment */
266 		if (sg->offset % 8) {
267 			dev_warn_once(mmc_dev(mmc),
268 				      "unaligned sg offset %u, disabling descriptor DMA for transfer\n",
269 				      sg->offset);
270 			return;
271 		}
272 	}
273 
274 	data->host_cookie |= SD_EMMC_DESC_CHAIN_MODE;
275 }
276 
277 static inline bool meson_mmc_desc_chain_mode(const struct mmc_data *data)
278 {
279 	return data->host_cookie & SD_EMMC_DESC_CHAIN_MODE;
280 }
281 
282 static inline bool meson_mmc_bounce_buf_read(const struct mmc_data *data)
283 {
284 	return data && data->flags & MMC_DATA_READ &&
285 	       !meson_mmc_desc_chain_mode(data);
286 }
287 
288 static void meson_mmc_pre_req(struct mmc_host *mmc, struct mmc_request *mrq)
289 {
290 	struct mmc_data *data = mrq->data;
291 
292 	if (!data)
293 		return;
294 
295 	meson_mmc_get_transfer_mode(mmc, mrq);
296 	data->host_cookie |= SD_EMMC_PRE_REQ_DONE;
297 
298 	if (!meson_mmc_desc_chain_mode(data))
299 		return;
300 
301 	data->sg_count = dma_map_sg(mmc_dev(mmc), data->sg, data->sg_len,
302                                    mmc_get_dma_dir(data));
303 	if (!data->sg_count)
304 		dev_err(mmc_dev(mmc), "dma_map_sg failed");
305 }
306 
307 static void meson_mmc_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
308 			       int err)
309 {
310 	struct mmc_data *data = mrq->data;
311 
312 	if (data && meson_mmc_desc_chain_mode(data) && data->sg_count)
313 		dma_unmap_sg(mmc_dev(mmc), data->sg, data->sg_len,
314 			     mmc_get_dma_dir(data));
315 }
316 
317 /*
318  * Gating the clock on this controller is tricky.  It seems the mmc clock
319  * is also used by the controller.  It may crash during some operation if the
320  * clock is stopped.  The safest thing to do, whenever possible, is to keep
321  * clock running at stop it at the pad using the pinmux.
322  */
323 static void meson_mmc_clk_gate(struct meson_host *host)
324 {
325 	u32 cfg;
326 
327 	if (host->pins_clk_gate) {
328 		pinctrl_select_state(host->pinctrl, host->pins_clk_gate);
329 	} else {
330 		/*
331 		 * If the pinmux is not provided - default to the classic and
332 		 * unsafe method
333 		 */
334 		cfg = readl(host->regs + SD_EMMC_CFG);
335 		cfg |= CFG_STOP_CLOCK;
336 		writel(cfg, host->regs + SD_EMMC_CFG);
337 	}
338 }
339 
340 static void meson_mmc_clk_ungate(struct meson_host *host)
341 {
342 	u32 cfg;
343 
344 	if (host->pins_clk_gate)
345 		pinctrl_select_default_state(host->dev);
346 
347 	/* Make sure the clock is not stopped in the controller */
348 	cfg = readl(host->regs + SD_EMMC_CFG);
349 	cfg &= ~CFG_STOP_CLOCK;
350 	writel(cfg, host->regs + SD_EMMC_CFG);
351 }
352 
353 static int meson_mmc_clk_set(struct meson_host *host, unsigned long rate,
354 			     bool ddr)
355 {
356 	struct mmc_host *mmc = host->mmc;
357 	int ret;
358 	u32 cfg;
359 
360 	/* Same request - bail-out */
361 	if (host->ddr == ddr && host->req_rate == rate)
362 		return 0;
363 
364 	/* stop clock */
365 	meson_mmc_clk_gate(host);
366 	host->req_rate = 0;
367 	mmc->actual_clock = 0;
368 
369 	/* return with clock being stopped */
370 	if (!rate)
371 		return 0;
372 
373 	/* Stop the clock during rate change to avoid glitches */
374 	cfg = readl(host->regs + SD_EMMC_CFG);
375 	cfg |= CFG_STOP_CLOCK;
376 	writel(cfg, host->regs + SD_EMMC_CFG);
377 
378 	if (ddr) {
379 		/* DDR modes require higher module clock */
380 		rate <<= 1;
381 		cfg |= CFG_DDR;
382 	} else {
383 		cfg &= ~CFG_DDR;
384 	}
385 	writel(cfg, host->regs + SD_EMMC_CFG);
386 	host->ddr = ddr;
387 
388 	ret = clk_set_rate(host->mmc_clk, rate);
389 	if (ret) {
390 		dev_err(host->dev, "Unable to set cfg_div_clk to %lu. ret=%d\n",
391 			rate, ret);
392 		return ret;
393 	}
394 
395 	host->req_rate = rate;
396 	mmc->actual_clock = clk_get_rate(host->mmc_clk);
397 
398 	/* We should report the real output frequency of the controller */
399 	if (ddr) {
400 		host->req_rate >>= 1;
401 		mmc->actual_clock >>= 1;
402 	}
403 
404 	dev_dbg(host->dev, "clk rate: %u Hz\n", mmc->actual_clock);
405 	if (rate != mmc->actual_clock)
406 		dev_dbg(host->dev, "requested rate was %lu\n", rate);
407 
408 	/* (re)start clock */
409 	meson_mmc_clk_ungate(host);
410 
411 	return 0;
412 }
413 
414 /*
415  * The SD/eMMC IP block has an internal mux and divider used for
416  * generating the MMC clock.  Use the clock framework to create and
417  * manage these clocks.
418  */
419 static int meson_mmc_clk_init(struct meson_host *host)
420 {
421 	struct clk_init_data init;
422 	struct clk_mux *mux;
423 	struct clk_divider *div;
424 	char clk_name[32];
425 	int i, ret = 0;
426 	const char *mux_parent_names[MUX_CLK_NUM_PARENTS];
427 	const char *clk_parent[1];
428 	u32 clk_reg;
429 
430 	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
431 	clk_reg = CLK_ALWAYS_ON(host);
432 	clk_reg |= CLK_DIV_MASK;
433 	clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, CLK_PHASE_180);
434 	clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, CLK_PHASE_0);
435 	clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, CLK_PHASE_0);
436 	if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
437 		clk_reg |= CLK_IRQ_SDIO_SLEEP(host);
438 	writel(clk_reg, host->regs + SD_EMMC_CLOCK);
439 
440 	/* get the mux parents */
441 	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
442 		struct clk *clk;
443 		char name[16];
444 
445 		snprintf(name, sizeof(name), "clkin%d", i);
446 		clk = devm_clk_get(host->dev, name);
447 		if (IS_ERR(clk))
448 			return dev_err_probe(host->dev, PTR_ERR(clk),
449 					     "Missing clock %s\n", name);
450 
451 		mux_parent_names[i] = __clk_get_name(clk);
452 	}
453 
454 	/* create the mux */
455 	mux = devm_kzalloc(host->dev, sizeof(*mux), GFP_KERNEL);
456 	if (!mux)
457 		return -ENOMEM;
458 
459 	snprintf(clk_name, sizeof(clk_name), "%s#mux", dev_name(host->dev));
460 	init.name = clk_name;
461 	init.ops = &clk_mux_ops;
462 	init.flags = 0;
463 	init.parent_names = mux_parent_names;
464 	init.num_parents = MUX_CLK_NUM_PARENTS;
465 
466 	mux->reg = host->regs + SD_EMMC_CLOCK;
467 	mux->shift = __ffs(CLK_SRC_MASK);
468 	mux->mask = CLK_SRC_MASK >> mux->shift;
469 	mux->hw.init = &init;
470 
471 	host->mux_clk = devm_clk_register(host->dev, &mux->hw);
472 	if (WARN_ON(IS_ERR(host->mux_clk)))
473 		return PTR_ERR(host->mux_clk);
474 
475 	/* create the divider */
476 	div = devm_kzalloc(host->dev, sizeof(*div), GFP_KERNEL);
477 	if (!div)
478 		return -ENOMEM;
479 
480 	snprintf(clk_name, sizeof(clk_name), "%s#div", dev_name(host->dev));
481 	init.name = clk_name;
482 	init.ops = &clk_divider_ops;
483 	init.flags = CLK_SET_RATE_PARENT;
484 	clk_parent[0] = __clk_get_name(host->mux_clk);
485 	init.parent_names = clk_parent;
486 	init.num_parents = 1;
487 
488 	div->reg = host->regs + SD_EMMC_CLOCK;
489 	div->shift = __ffs(CLK_DIV_MASK);
490 	div->width = __builtin_popcountl(CLK_DIV_MASK);
491 	div->hw.init = &init;
492 	div->flags = CLK_DIVIDER_ONE_BASED;
493 
494 	host->mmc_clk = devm_clk_register(host->dev, &div->hw);
495 	if (WARN_ON(IS_ERR(host->mmc_clk)))
496 		return PTR_ERR(host->mmc_clk);
497 
498 	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
499 	host->mmc->f_min = clk_round_rate(host->mmc_clk, 400000);
500 	ret = clk_set_rate(host->mmc_clk, host->mmc->f_min);
501 	if (ret)
502 		return ret;
503 
504 	return clk_prepare_enable(host->mmc_clk);
505 }
506 
507 static void meson_mmc_disable_resampling(struct meson_host *host)
508 {
509 	unsigned int val = readl(host->regs + host->data->adjust);
510 
511 	val &= ~ADJUST_ADJ_EN;
512 	writel(val, host->regs + host->data->adjust);
513 }
514 
515 static void meson_mmc_reset_resampling(struct meson_host *host)
516 {
517 	unsigned int val;
518 
519 	meson_mmc_disable_resampling(host);
520 
521 	val = readl(host->regs + host->data->adjust);
522 	val &= ~ADJUST_ADJ_DELAY_MASK;
523 	writel(val, host->regs + host->data->adjust);
524 }
525 
526 static int meson_mmc_resampling_tuning(struct mmc_host *mmc, u32 opcode)
527 {
528 	struct meson_host *host = mmc_priv(mmc);
529 	unsigned int val, dly, max_dly, i;
530 	int ret;
531 
532 	/* Resampling is done using the source clock */
533 	max_dly = DIV_ROUND_UP(clk_get_rate(host->mux_clk),
534 			       clk_get_rate(host->mmc_clk));
535 
536 	val = readl(host->regs + host->data->adjust);
537 	val |= ADJUST_ADJ_EN;
538 	writel(val, host->regs + host->data->adjust);
539 
540 	if (mmc_doing_retune(mmc))
541 		dly = FIELD_GET(ADJUST_ADJ_DELAY_MASK, val) + 1;
542 	else
543 		dly = 0;
544 
545 	for (i = 0; i < max_dly; i++) {
546 		val &= ~ADJUST_ADJ_DELAY_MASK;
547 		val |= FIELD_PREP(ADJUST_ADJ_DELAY_MASK, (dly + i) % max_dly);
548 		writel(val, host->regs + host->data->adjust);
549 
550 		ret = mmc_send_tuning(mmc, opcode, NULL);
551 		if (!ret) {
552 			dev_dbg(mmc_dev(mmc), "resampling delay: %u\n",
553 				(dly + i) % max_dly);
554 			return 0;
555 		}
556 	}
557 
558 	meson_mmc_reset_resampling(host);
559 	return -EIO;
560 }
561 
562 static int meson_mmc_prepare_ios_clock(struct meson_host *host,
563 				       struct mmc_ios *ios)
564 {
565 	bool ddr;
566 
567 	switch (ios->timing) {
568 	case MMC_TIMING_MMC_DDR52:
569 	case MMC_TIMING_UHS_DDR50:
570 		ddr = true;
571 		break;
572 
573 	default:
574 		ddr = false;
575 		break;
576 	}
577 
578 	return meson_mmc_clk_set(host, ios->clock, ddr);
579 }
580 
581 static void meson_mmc_check_resampling(struct meson_host *host,
582 				       struct mmc_ios *ios)
583 {
584 	switch (ios->timing) {
585 	case MMC_TIMING_LEGACY:
586 	case MMC_TIMING_MMC_HS:
587 	case MMC_TIMING_SD_HS:
588 	case MMC_TIMING_MMC_DDR52:
589 		meson_mmc_disable_resampling(host);
590 		break;
591 	}
592 }
593 
594 static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
595 {
596 	struct meson_host *host = mmc_priv(mmc);
597 	u32 bus_width, val;
598 	int err;
599 
600 	/*
601 	 * GPIO regulator, only controls switching between 1v8 and
602 	 * 3v3, doesn't support MMC_POWER_OFF, MMC_POWER_ON.
603 	 */
604 	switch (ios->power_mode) {
605 	case MMC_POWER_OFF:
606 		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
607 		mmc_regulator_disable_vqmmc(mmc);
608 
609 		break;
610 
611 	case MMC_POWER_UP:
612 		mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
613 
614 		break;
615 
616 	case MMC_POWER_ON:
617 		mmc_regulator_enable_vqmmc(mmc);
618 
619 		break;
620 	}
621 
622 	/* Bus width */
623 	switch (ios->bus_width) {
624 	case MMC_BUS_WIDTH_1:
625 		bus_width = CFG_BUS_WIDTH_1;
626 		break;
627 	case MMC_BUS_WIDTH_4:
628 		bus_width = CFG_BUS_WIDTH_4;
629 		break;
630 	case MMC_BUS_WIDTH_8:
631 		bus_width = CFG_BUS_WIDTH_8;
632 		break;
633 	default:
634 		dev_err(host->dev, "Invalid ios->bus_width: %u.  Setting to 4.\n",
635 			ios->bus_width);
636 		bus_width = CFG_BUS_WIDTH_4;
637 	}
638 
639 	val = readl(host->regs + SD_EMMC_CFG);
640 	val &= ~CFG_BUS_WIDTH_MASK;
641 	val |= FIELD_PREP(CFG_BUS_WIDTH_MASK, bus_width);
642 	writel(val, host->regs + SD_EMMC_CFG);
643 
644 	meson_mmc_check_resampling(host, ios);
645 	err = meson_mmc_prepare_ios_clock(host, ios);
646 	if (err)
647 		dev_err(host->dev, "Failed to set clock: %d\n,", err);
648 
649 	dev_dbg(host->dev, "SD_EMMC_CFG:  0x%08x\n", val);
650 }
651 
652 static void meson_mmc_request_done(struct mmc_host *mmc,
653 				   struct mmc_request *mrq)
654 {
655 	struct meson_host *host = mmc_priv(mmc);
656 
657 	host->cmd = NULL;
658 	if (host->needs_pre_post_req)
659 		meson_mmc_post_req(mmc, mrq, 0);
660 	mmc_request_done(host->mmc, mrq);
661 }
662 
663 static void meson_mmc_set_blksz(struct mmc_host *mmc, unsigned int blksz)
664 {
665 	struct meson_host *host = mmc_priv(mmc);
666 	u32 cfg, blksz_old;
667 
668 	cfg = readl(host->regs + SD_EMMC_CFG);
669 	blksz_old = FIELD_GET(CFG_BLK_LEN_MASK, cfg);
670 
671 	if (!is_power_of_2(blksz))
672 		dev_err(host->dev, "blksz %u is not a power of 2\n", blksz);
673 
674 	blksz = ilog2(blksz);
675 
676 	/* check if block-size matches, if not update */
677 	if (blksz == blksz_old)
678 		return;
679 
680 	dev_dbg(host->dev, "%s: update blk_len %d -> %d\n", __func__,
681 		blksz_old, blksz);
682 
683 	cfg &= ~CFG_BLK_LEN_MASK;
684 	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, blksz);
685 	writel(cfg, host->regs + SD_EMMC_CFG);
686 }
687 
688 static void meson_mmc_set_response_bits(struct mmc_command *cmd, u32 *cmd_cfg)
689 {
690 	if (cmd->flags & MMC_RSP_PRESENT) {
691 		if (cmd->flags & MMC_RSP_136)
692 			*cmd_cfg |= CMD_CFG_RESP_128;
693 		*cmd_cfg |= CMD_CFG_RESP_NUM;
694 
695 		if (!(cmd->flags & MMC_RSP_CRC))
696 			*cmd_cfg |= CMD_CFG_RESP_NOCRC;
697 
698 		if (cmd->flags & MMC_RSP_BUSY)
699 			*cmd_cfg |= CMD_CFG_R1B;
700 	} else {
701 		*cmd_cfg |= CMD_CFG_NO_RESP;
702 	}
703 }
704 
705 static void meson_mmc_desc_chain_transfer(struct mmc_host *mmc, u32 cmd_cfg)
706 {
707 	struct meson_host *host = mmc_priv(mmc);
708 	struct sd_emmc_desc *desc = host->descs;
709 	struct mmc_data *data = host->cmd->data;
710 	struct scatterlist *sg;
711 	u32 start;
712 	int i;
713 
714 	if (data->flags & MMC_DATA_WRITE)
715 		cmd_cfg |= CMD_CFG_DATA_WR;
716 
717 	if (data->blocks > 1) {
718 		cmd_cfg |= CMD_CFG_BLOCK_MODE;
719 		meson_mmc_set_blksz(mmc, data->blksz);
720 	}
721 
722 	for_each_sg(data->sg, sg, data->sg_count, i) {
723 		unsigned int len = sg_dma_len(sg);
724 
725 		if (data->blocks > 1)
726 			len /= data->blksz;
727 
728 		desc[i].cmd_cfg = cmd_cfg;
729 		desc[i].cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, len);
730 		if (i > 0)
731 			desc[i].cmd_cfg |= CMD_CFG_NO_CMD;
732 		desc[i].cmd_arg = host->cmd->arg;
733 		desc[i].cmd_resp = 0;
734 		desc[i].cmd_data = sg_dma_address(sg);
735 	}
736 	desc[data->sg_count - 1].cmd_cfg |= CMD_CFG_END_OF_CHAIN;
737 
738 	dma_wmb(); /* ensure descriptor is written before kicked */
739 	start = host->descs_dma_addr | START_DESC_BUSY;
740 	writel(start, host->regs + SD_EMMC_START);
741 }
742 
743 /* local sg copy for dram_access_quirk */
744 static void meson_mmc_copy_buffer(struct meson_host *host, struct mmc_data *data,
745 				  size_t buflen, bool to_buffer)
746 {
747 	unsigned int sg_flags = SG_MITER_ATOMIC;
748 	struct scatterlist *sgl = data->sg;
749 	unsigned int nents = data->sg_len;
750 	struct sg_mapping_iter miter;
751 	unsigned int offset = 0;
752 
753 	if (to_buffer)
754 		sg_flags |= SG_MITER_FROM_SG;
755 	else
756 		sg_flags |= SG_MITER_TO_SG;
757 
758 	sg_miter_start(&miter, sgl, nents, sg_flags);
759 
760 	while ((offset < buflen) && sg_miter_next(&miter)) {
761 		unsigned int buf_offset = 0;
762 		unsigned int len, left;
763 		u32 *buf = miter.addr;
764 
765 		len = min(miter.length, buflen - offset);
766 		left = len;
767 
768 		if (to_buffer) {
769 			do {
770 				writel(*buf++, host->bounce_iomem_buf + offset + buf_offset);
771 
772 				buf_offset += 4;
773 				left -= 4;
774 			} while (left);
775 		} else {
776 			do {
777 				*buf++ = readl(host->bounce_iomem_buf + offset + buf_offset);
778 
779 				buf_offset += 4;
780 				left -= 4;
781 			} while (left);
782 		}
783 
784 		offset += len;
785 	}
786 
787 	sg_miter_stop(&miter);
788 }
789 
790 static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
791 {
792 	struct meson_host *host = mmc_priv(mmc);
793 	struct mmc_data *data = cmd->data;
794 	u32 cmd_cfg = 0, cmd_data = 0;
795 	unsigned int xfer_bytes = 0;
796 
797 	/* Setup descriptors */
798 	dma_rmb();
799 
800 	host->cmd = cmd;
801 
802 	cmd_cfg |= FIELD_PREP(CMD_CFG_CMD_INDEX_MASK, cmd->opcode);
803 	cmd_cfg |= CMD_CFG_OWNER;  /* owned by CPU */
804 
805 	meson_mmc_set_response_bits(cmd, &cmd_cfg);
806 
807 	/* data? */
808 	if (data) {
809 		data->bytes_xfered = 0;
810 		cmd_cfg |= CMD_CFG_DATA_IO;
811 		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
812 				      ilog2(meson_mmc_get_timeout_msecs(data)));
813 
814 		if (meson_mmc_desc_chain_mode(data)) {
815 			meson_mmc_desc_chain_transfer(mmc, cmd_cfg);
816 			return;
817 		}
818 
819 		if (data->blocks > 1) {
820 			cmd_cfg |= CMD_CFG_BLOCK_MODE;
821 			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK,
822 					      data->blocks);
823 			meson_mmc_set_blksz(mmc, data->blksz);
824 		} else {
825 			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, data->blksz);
826 		}
827 
828 		xfer_bytes = data->blksz * data->blocks;
829 		if (data->flags & MMC_DATA_WRITE) {
830 			cmd_cfg |= CMD_CFG_DATA_WR;
831 			WARN_ON(xfer_bytes > host->bounce_buf_size);
832 			if (host->dram_access_quirk)
833 				meson_mmc_copy_buffer(host, data, xfer_bytes, true);
834 			else
835 				sg_copy_to_buffer(data->sg, data->sg_len,
836 						  host->bounce_buf, xfer_bytes);
837 			dma_wmb();
838 		}
839 
840 		cmd_data = host->bounce_dma_addr & CMD_DATA_MASK;
841 	} else {
842 		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
843 				      ilog2(SD_EMMC_CMD_TIMEOUT));
844 	}
845 
846 	/* Last descriptor */
847 	cmd_cfg |= CMD_CFG_END_OF_CHAIN;
848 	writel(cmd_cfg, host->regs + SD_EMMC_CMD_CFG);
849 	writel(cmd_data, host->regs + SD_EMMC_CMD_DAT);
850 	writel(0, host->regs + SD_EMMC_CMD_RSP);
851 	wmb(); /* ensure descriptor is written before kicked */
852 	writel(cmd->arg, host->regs + SD_EMMC_CMD_ARG);
853 }
854 
855 static int meson_mmc_validate_dram_access(struct mmc_host *mmc, struct mmc_data *data)
856 {
857 	struct scatterlist *sg;
858 	int i;
859 
860 	/* Reject request if any element offset or size is not 32bit aligned */
861 	for_each_sg(data->sg, sg, data->sg_len, i) {
862 		if (!IS_ALIGNED(sg->offset, sizeof(u32)) ||
863 		    !IS_ALIGNED(sg->length, sizeof(u32))) {
864 			dev_err(mmc_dev(mmc), "unaligned sg offset %u len %u\n",
865 				data->sg->offset, data->sg->length);
866 			return -EINVAL;
867 		}
868 	}
869 
870 	return 0;
871 }
872 
873 static void meson_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
874 {
875 	struct meson_host *host = mmc_priv(mmc);
876 	host->needs_pre_post_req = mrq->data &&
877 			!(mrq->data->host_cookie & SD_EMMC_PRE_REQ_DONE);
878 
879 	/*
880 	 * The memory at the end of the controller used as bounce buffer for
881 	 * the dram_access_quirk only accepts 32bit read/write access,
882 	 * check the aligment and length of the data before starting the request.
883 	 */
884 	if (host->dram_access_quirk && mrq->data) {
885 		mrq->cmd->error = meson_mmc_validate_dram_access(mmc, mrq->data);
886 		if (mrq->cmd->error) {
887 			mmc_request_done(mmc, mrq);
888 			return;
889 		}
890 	}
891 
892 	if (host->needs_pre_post_req) {
893 		meson_mmc_get_transfer_mode(mmc, mrq);
894 		if (!meson_mmc_desc_chain_mode(mrq->data))
895 			host->needs_pre_post_req = false;
896 	}
897 
898 	if (host->needs_pre_post_req)
899 		meson_mmc_pre_req(mmc, mrq);
900 
901 	/* Stop execution */
902 	writel(0, host->regs + SD_EMMC_START);
903 
904 	meson_mmc_start_cmd(mmc, mrq->sbc ?: mrq->cmd);
905 }
906 
907 static void meson_mmc_read_resp(struct mmc_host *mmc, struct mmc_command *cmd)
908 {
909 	struct meson_host *host = mmc_priv(mmc);
910 
911 	if (cmd->flags & MMC_RSP_136) {
912 		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP3);
913 		cmd->resp[1] = readl(host->regs + SD_EMMC_CMD_RSP2);
914 		cmd->resp[2] = readl(host->regs + SD_EMMC_CMD_RSP1);
915 		cmd->resp[3] = readl(host->regs + SD_EMMC_CMD_RSP);
916 	} else if (cmd->flags & MMC_RSP_PRESENT) {
917 		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP);
918 	}
919 }
920 
921 static void __meson_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
922 {
923 	struct meson_host *host = mmc_priv(mmc);
924 	u32 reg_irqen = IRQ_EN_MASK;
925 
926 	if (enable)
927 		reg_irqen |= IRQ_SDIO;
928 	writel(reg_irqen, host->regs + SD_EMMC_IRQ_EN);
929 }
930 
931 static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
932 {
933 	struct meson_host *host = dev_id;
934 	struct mmc_command *cmd;
935 	u32 status, raw_status, irq_mask = IRQ_EN_MASK;
936 	irqreturn_t ret = IRQ_NONE;
937 
938 	if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
939 		irq_mask |= IRQ_SDIO;
940 	raw_status = readl(host->regs + SD_EMMC_STATUS);
941 	status = raw_status & irq_mask;
942 
943 	if (!status) {
944 		dev_dbg(host->dev,
945 			"Unexpected IRQ! irq_en 0x%08x - status 0x%08x\n",
946 			 irq_mask, raw_status);
947 		return IRQ_NONE;
948 	}
949 
950 	/* ack all raised interrupts */
951 	writel(status, host->regs + SD_EMMC_STATUS);
952 
953 	cmd = host->cmd;
954 
955 	if (status & IRQ_SDIO) {
956 		spin_lock(&host->lock);
957 		__meson_mmc_enable_sdio_irq(host->mmc, 0);
958 		sdio_signal_irq(host->mmc);
959 		spin_unlock(&host->lock);
960 		status &= ~IRQ_SDIO;
961 		if (!status)
962 			return IRQ_HANDLED;
963 	}
964 
965 	if (WARN_ON(!cmd))
966 		return IRQ_NONE;
967 
968 	cmd->error = 0;
969 	if (status & IRQ_CRC_ERR) {
970 		dev_dbg(host->dev, "CRC Error - status 0x%08x\n", status);
971 		cmd->error = -EILSEQ;
972 		ret = IRQ_WAKE_THREAD;
973 		goto out;
974 	}
975 
976 	if (status & IRQ_TIMEOUTS) {
977 		dev_dbg(host->dev, "Timeout - status 0x%08x\n", status);
978 		cmd->error = -ETIMEDOUT;
979 		ret = IRQ_WAKE_THREAD;
980 		goto out;
981 	}
982 
983 	meson_mmc_read_resp(host->mmc, cmd);
984 
985 	if (status & (IRQ_END_OF_CHAIN | IRQ_RESP_STATUS)) {
986 		struct mmc_data *data = cmd->data;
987 
988 		if (data && !cmd->error)
989 			data->bytes_xfered = data->blksz * data->blocks;
990 
991 		return IRQ_WAKE_THREAD;
992 	}
993 
994 out:
995 	if (cmd->error) {
996 		/* Stop desc in case of errors */
997 		u32 start = readl(host->regs + SD_EMMC_START);
998 
999 		start &= ~START_DESC_BUSY;
1000 		writel(start, host->regs + SD_EMMC_START);
1001 	}
1002 
1003 	return ret;
1004 }
1005 
1006 static int meson_mmc_wait_desc_stop(struct meson_host *host)
1007 {
1008 	u32 status;
1009 
1010 	/*
1011 	 * It may sometimes take a while for it to actually halt. Here, we
1012 	 * are giving it 5ms to comply
1013 	 *
1014 	 * If we don't confirm the descriptor is stopped, it might raise new
1015 	 * IRQs after we have called mmc_request_done() which is bad.
1016 	 */
1017 
1018 	return readl_poll_timeout(host->regs + SD_EMMC_STATUS, status,
1019 				  !(status & (STATUS_BUSY | STATUS_DESC_BUSY)),
1020 				  100, 5000);
1021 }
1022 
1023 static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id)
1024 {
1025 	struct meson_host *host = dev_id;
1026 	struct mmc_command *next_cmd, *cmd = host->cmd;
1027 	struct mmc_data *data;
1028 	unsigned int xfer_bytes;
1029 
1030 	if (WARN_ON(!cmd))
1031 		return IRQ_NONE;
1032 
1033 	if (cmd->error) {
1034 		meson_mmc_wait_desc_stop(host);
1035 		meson_mmc_request_done(host->mmc, cmd->mrq);
1036 
1037 		return IRQ_HANDLED;
1038 	}
1039 
1040 	data = cmd->data;
1041 	if (meson_mmc_bounce_buf_read(data)) {
1042 		xfer_bytes = data->blksz * data->blocks;
1043 		WARN_ON(xfer_bytes > host->bounce_buf_size);
1044 		if (host->dram_access_quirk)
1045 			meson_mmc_copy_buffer(host, data, xfer_bytes, false);
1046 		else
1047 			sg_copy_from_buffer(data->sg, data->sg_len,
1048 					    host->bounce_buf, xfer_bytes);
1049 	}
1050 
1051 	next_cmd = meson_mmc_get_next_command(cmd);
1052 	if (next_cmd)
1053 		meson_mmc_start_cmd(host->mmc, next_cmd);
1054 	else
1055 		meson_mmc_request_done(host->mmc, cmd->mrq);
1056 
1057 	return IRQ_HANDLED;
1058 }
1059 
1060 static void meson_mmc_cfg_init(struct meson_host *host)
1061 {
1062 	u32 cfg = 0;
1063 
1064 	cfg |= FIELD_PREP(CFG_RESP_TIMEOUT_MASK,
1065 			  ilog2(SD_EMMC_CFG_RESP_TIMEOUT));
1066 	cfg |= FIELD_PREP(CFG_RC_CC_MASK, ilog2(SD_EMMC_CFG_CMD_GAP));
1067 	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, ilog2(SD_EMMC_CFG_BLK_SIZE));
1068 
1069 	/* abort chain on R/W errors */
1070 	cfg |= CFG_ERR_ABORT;
1071 
1072 	writel(cfg, host->regs + SD_EMMC_CFG);
1073 }
1074 
1075 static int meson_mmc_card_busy(struct mmc_host *mmc)
1076 {
1077 	struct meson_host *host = mmc_priv(mmc);
1078 	u32 regval;
1079 
1080 	regval = readl(host->regs + SD_EMMC_STATUS);
1081 
1082 	/* We are only interrested in lines 0 to 3, so mask the other ones */
1083 	return !(FIELD_GET(STATUS_DATI, regval) & 0xf);
1084 }
1085 
1086 static int meson_mmc_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
1087 {
1088 	int ret;
1089 
1090 	/* vqmmc regulator is available */
1091 	if (!IS_ERR(mmc->supply.vqmmc)) {
1092 		/*
1093 		 * The usual amlogic setup uses a GPIO to switch from one
1094 		 * regulator to the other. While the voltage ramp up is
1095 		 * pretty fast, care must be taken when switching from 3.3v
1096 		 * to 1.8v. Please make sure the regulator framework is aware
1097 		 * of your own regulator constraints
1098 		 */
1099 		ret = mmc_regulator_set_vqmmc(mmc, ios);
1100 		return ret < 0 ? ret : 0;
1101 	}
1102 
1103 	/* no vqmmc regulator, assume fixed regulator at 3/3.3V */
1104 	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
1105 		return 0;
1106 
1107 	return -EINVAL;
1108 }
1109 
1110 static void meson_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
1111 {
1112 	struct meson_host *host = mmc_priv(mmc);
1113 	unsigned long flags;
1114 
1115 	spin_lock_irqsave(&host->lock, flags);
1116 	__meson_mmc_enable_sdio_irq(mmc, enable);
1117 	spin_unlock_irqrestore(&host->lock, flags);
1118 }
1119 
1120 static void meson_mmc_ack_sdio_irq(struct mmc_host *mmc)
1121 {
1122 	meson_mmc_enable_sdio_irq(mmc, 1);
1123 }
1124 
1125 static const struct mmc_host_ops meson_mmc_ops = {
1126 	.request	= meson_mmc_request,
1127 	.set_ios	= meson_mmc_set_ios,
1128 	.get_cd         = mmc_gpio_get_cd,
1129 	.pre_req	= meson_mmc_pre_req,
1130 	.post_req	= meson_mmc_post_req,
1131 	.execute_tuning = meson_mmc_resampling_tuning,
1132 	.card_busy	= meson_mmc_card_busy,
1133 	.start_signal_voltage_switch = meson_mmc_voltage_switch,
1134 	.enable_sdio_irq = meson_mmc_enable_sdio_irq,
1135 	.ack_sdio_irq	= meson_mmc_ack_sdio_irq,
1136 };
1137 
1138 static int meson_mmc_probe(struct platform_device *pdev)
1139 {
1140 	struct resource *res;
1141 	struct meson_host *host;
1142 	struct mmc_host *mmc;
1143 	struct clk *core_clk;
1144 	int cd_irq, ret;
1145 
1146 	mmc = devm_mmc_alloc_host(&pdev->dev, sizeof(struct meson_host));
1147 	if (!mmc)
1148 		return -ENOMEM;
1149 	host = mmc_priv(mmc);
1150 	host->mmc = mmc;
1151 	host->dev = &pdev->dev;
1152 	dev_set_drvdata(&pdev->dev, host);
1153 
1154 	/* The G12A SDIO Controller needs an SRAM bounce buffer */
1155 	host->dram_access_quirk = device_property_read_bool(&pdev->dev,
1156 					"amlogic,dram-access-quirk");
1157 
1158 	/* Get regulators and the supported OCR mask */
1159 	ret = mmc_regulator_get_supply(mmc);
1160 	if (ret)
1161 		return ret;
1162 
1163 	ret = mmc_of_parse(mmc);
1164 	if (ret)
1165 		return dev_err_probe(&pdev->dev, ret, "error parsing DT\n");
1166 
1167 	mmc->caps |= MMC_CAP_CMD23;
1168 
1169 	if (mmc->caps & MMC_CAP_SDIO_IRQ)
1170 		mmc->caps2 |= MMC_CAP2_SDIO_IRQ_NOTHREAD;
1171 
1172 	host->data = of_device_get_match_data(&pdev->dev);
1173 	if (!host->data)
1174 		return -EINVAL;
1175 
1176 	ret = device_reset_optional(&pdev->dev);
1177 	if (ret)
1178 		return dev_err_probe(&pdev->dev, ret, "device reset failed\n");
1179 
1180 	host->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1181 	if (IS_ERR(host->regs))
1182 		return PTR_ERR(host->regs);
1183 
1184 	host->irq = platform_get_irq(pdev, 0);
1185 	if (host->irq < 0)
1186 		return host->irq;
1187 
1188 	cd_irq = platform_get_irq_optional(pdev, 1);
1189 	mmc_gpio_set_cd_irq(mmc, cd_irq);
1190 
1191 	host->pinctrl = devm_pinctrl_get(&pdev->dev);
1192 	if (IS_ERR(host->pinctrl))
1193 		return PTR_ERR(host->pinctrl);
1194 
1195 	host->pins_clk_gate = pinctrl_lookup_state(host->pinctrl,
1196 						   "clk-gate");
1197 	if (IS_ERR(host->pins_clk_gate)) {
1198 		dev_warn(&pdev->dev,
1199 			 "can't get clk-gate pinctrl, using clk_stop bit\n");
1200 		host->pins_clk_gate = NULL;
1201 	}
1202 
1203 	core_clk = devm_clk_get_enabled(&pdev->dev, "core");
1204 	if (IS_ERR(core_clk))
1205 		return PTR_ERR(core_clk);
1206 
1207 	ret = meson_mmc_clk_init(host);
1208 	if (ret)
1209 		return ret;
1210 
1211 	/* set config to sane default */
1212 	meson_mmc_cfg_init(host);
1213 
1214 	/* Stop execution */
1215 	writel(0, host->regs + SD_EMMC_START);
1216 
1217 	/* clear, ack and enable interrupts */
1218 	writel(0, host->regs + SD_EMMC_IRQ_EN);
1219 	writel(IRQ_EN_MASK, host->regs + SD_EMMC_STATUS);
1220 	writel(IRQ_EN_MASK, host->regs + SD_EMMC_IRQ_EN);
1221 
1222 	ret = request_threaded_irq(host->irq, meson_mmc_irq,
1223 				   meson_mmc_irq_thread, IRQF_ONESHOT,
1224 				   dev_name(&pdev->dev), host);
1225 	if (ret)
1226 		goto err_init_clk;
1227 
1228 	spin_lock_init(&host->lock);
1229 
1230 	if (host->dram_access_quirk) {
1231 		/* Limit segments to 1 due to low available sram memory */
1232 		mmc->max_segs = 1;
1233 		/* Limit to the available sram memory */
1234 		mmc->max_blk_count = SD_EMMC_SRAM_DATA_BUF_LEN /
1235 				     mmc->max_blk_size;
1236 	} else {
1237 		mmc->max_blk_count = CMD_CFG_LENGTH_MASK;
1238 		mmc->max_segs = SD_EMMC_DESC_BUF_LEN /
1239 				sizeof(struct sd_emmc_desc);
1240 	}
1241 	mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
1242 	mmc->max_seg_size = mmc->max_req_size;
1243 
1244 	/*
1245 	 * At the moment, we don't know how to reliably enable HS400.
1246 	 * From the different datasheets, it is not even clear if this mode
1247 	 * is officially supported by any of the SoCs
1248 	 */
1249 	mmc->caps2 &= ~MMC_CAP2_HS400;
1250 
1251 	if (host->dram_access_quirk) {
1252 		/*
1253 		 * The MMC Controller embeds 1,5KiB of internal SRAM
1254 		 * that can be used to be used as bounce buffer.
1255 		 * In the case of the G12A SDIO controller, use these
1256 		 * instead of the DDR memory
1257 		 */
1258 		host->bounce_buf_size = SD_EMMC_SRAM_DATA_BUF_LEN;
1259 		host->bounce_iomem_buf = host->regs + SD_EMMC_SRAM_DATA_BUF_OFF;
1260 		host->bounce_dma_addr = res->start + SD_EMMC_SRAM_DATA_BUF_OFF;
1261 	} else {
1262 		/* data bounce buffer */
1263 		host->bounce_buf_size = mmc->max_req_size;
1264 		host->bounce_buf =
1265 			dmam_alloc_coherent(host->dev, host->bounce_buf_size,
1266 					    &host->bounce_dma_addr, GFP_KERNEL);
1267 		if (host->bounce_buf == NULL) {
1268 			dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n");
1269 			ret = -ENOMEM;
1270 			goto err_free_irq;
1271 		}
1272 	}
1273 
1274 	host->descs = dmam_alloc_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
1275 					  &host->descs_dma_addr, GFP_KERNEL);
1276 	if (!host->descs) {
1277 		dev_err(host->dev, "Allocating descriptor DMA buffer failed\n");
1278 		ret = -ENOMEM;
1279 		goto err_free_irq;
1280 	}
1281 
1282 	mmc->ops = &meson_mmc_ops;
1283 	ret = mmc_add_host(mmc);
1284 	if (ret)
1285 		goto err_free_irq;
1286 
1287 	return 0;
1288 
1289 err_free_irq:
1290 	free_irq(host->irq, host);
1291 err_init_clk:
1292 	clk_disable_unprepare(host->mmc_clk);
1293 	return ret;
1294 }
1295 
1296 static void meson_mmc_remove(struct platform_device *pdev)
1297 {
1298 	struct meson_host *host = dev_get_drvdata(&pdev->dev);
1299 
1300 	mmc_remove_host(host->mmc);
1301 
1302 	/* disable interrupts */
1303 	writel(0, host->regs + SD_EMMC_IRQ_EN);
1304 	free_irq(host->irq, host);
1305 
1306 	clk_disable_unprepare(host->mmc_clk);
1307 }
1308 
1309 static const struct meson_mmc_data meson_gx_data = {
1310 	.tx_delay_mask	= CLK_V2_TX_DELAY_MASK,
1311 	.rx_delay_mask	= CLK_V2_RX_DELAY_MASK,
1312 	.always_on	= CLK_V2_ALWAYS_ON,
1313 	.adjust		= SD_EMMC_ADJUST,
1314 	.irq_sdio_sleep	= CLK_V2_IRQ_SDIO_SLEEP,
1315 };
1316 
1317 static const struct meson_mmc_data meson_axg_data = {
1318 	.tx_delay_mask	= CLK_V3_TX_DELAY_MASK,
1319 	.rx_delay_mask	= CLK_V3_RX_DELAY_MASK,
1320 	.always_on	= CLK_V3_ALWAYS_ON,
1321 	.adjust		= SD_EMMC_V3_ADJUST,
1322 	.irq_sdio_sleep	= CLK_V3_IRQ_SDIO_SLEEP,
1323 };
1324 
1325 static const struct of_device_id meson_mmc_of_match[] = {
1326 	{ .compatible = "amlogic,meson-gx-mmc",		.data = &meson_gx_data },
1327 	{ .compatible = "amlogic,meson-gxbb-mmc", 	.data = &meson_gx_data },
1328 	{ .compatible = "amlogic,meson-gxl-mmc",	.data = &meson_gx_data },
1329 	{ .compatible = "amlogic,meson-gxm-mmc",	.data = &meson_gx_data },
1330 	{ .compatible = "amlogic,meson-axg-mmc",	.data = &meson_axg_data },
1331 	{}
1332 };
1333 MODULE_DEVICE_TABLE(of, meson_mmc_of_match);
1334 
1335 static struct platform_driver meson_mmc_driver = {
1336 	.probe		= meson_mmc_probe,
1337 	.remove_new	= meson_mmc_remove,
1338 	.driver		= {
1339 		.name = DRIVER_NAME,
1340 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1341 		.of_match_table = meson_mmc_of_match,
1342 	},
1343 };
1344 
1345 module_platform_driver(meson_mmc_driver);
1346 
1347 MODULE_DESCRIPTION("Amlogic S905*/GX*/AXG SD/eMMC driver");
1348 MODULE_AUTHOR("Kevin Hilman <khilman@baylibre.com>");
1349 MODULE_LICENSE("GPL v2");
1350