xref: /openbmc/linux/drivers/mmc/host/meson-gx-mmc.c (revision 5da094ac)
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_device.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 vqmmc_enabled;
178 	bool needs_pre_post_req;
179 
180 	spinlock_t lock;
181 };
182 
183 #define CMD_CFG_LENGTH_MASK GENMASK(8, 0)
184 #define CMD_CFG_BLOCK_MODE BIT(9)
185 #define CMD_CFG_R1B BIT(10)
186 #define CMD_CFG_END_OF_CHAIN BIT(11)
187 #define CMD_CFG_TIMEOUT_MASK GENMASK(15, 12)
188 #define CMD_CFG_NO_RESP BIT(16)
189 #define CMD_CFG_NO_CMD BIT(17)
190 #define CMD_CFG_DATA_IO BIT(18)
191 #define CMD_CFG_DATA_WR BIT(19)
192 #define CMD_CFG_RESP_NOCRC BIT(20)
193 #define CMD_CFG_RESP_128 BIT(21)
194 #define CMD_CFG_RESP_NUM BIT(22)
195 #define CMD_CFG_DATA_NUM BIT(23)
196 #define CMD_CFG_CMD_INDEX_MASK GENMASK(29, 24)
197 #define CMD_CFG_ERROR BIT(30)
198 #define CMD_CFG_OWNER BIT(31)
199 
200 #define CMD_DATA_MASK GENMASK(31, 2)
201 #define CMD_DATA_BIG_ENDIAN BIT(1)
202 #define CMD_DATA_SRAM BIT(0)
203 #define CMD_RESP_MASK GENMASK(31, 1)
204 #define CMD_RESP_SRAM BIT(0)
205 
206 static unsigned int meson_mmc_get_timeout_msecs(struct mmc_data *data)
207 {
208 	unsigned int timeout = data->timeout_ns / NSEC_PER_MSEC;
209 
210 	if (!timeout)
211 		return SD_EMMC_CMD_TIMEOUT_DATA;
212 
213 	timeout = roundup_pow_of_two(timeout);
214 
215 	return min(timeout, 32768U); /* max. 2^15 ms */
216 }
217 
218 static struct mmc_command *meson_mmc_get_next_command(struct mmc_command *cmd)
219 {
220 	if (cmd->opcode == MMC_SET_BLOCK_COUNT && !cmd->error)
221 		return cmd->mrq->cmd;
222 	else if (mmc_op_multi(cmd->opcode) &&
223 		 (!cmd->mrq->sbc || cmd->error || cmd->data->error))
224 		return cmd->mrq->stop;
225 	else
226 		return NULL;
227 }
228 
229 static void meson_mmc_get_transfer_mode(struct mmc_host *mmc,
230 					struct mmc_request *mrq)
231 {
232 	struct meson_host *host = mmc_priv(mmc);
233 	struct mmc_data *data = mrq->data;
234 	struct scatterlist *sg;
235 	int i;
236 
237 	/*
238 	 * When Controller DMA cannot directly access DDR memory, disable
239 	 * support for Chain Mode to directly use the internal SRAM using
240 	 * the bounce buffer mode.
241 	 */
242 	if (host->dram_access_quirk)
243 		return;
244 
245 	/* SD_IO_RW_EXTENDED (CMD53) can also use block mode under the hood */
246 	if (data->blocks > 1 || mrq->cmd->opcode == SD_IO_RW_EXTENDED) {
247 		/*
248 		 * In block mode DMA descriptor format, "length" field indicates
249 		 * number of blocks and there is no way to pass DMA size that
250 		 * is not multiple of SDIO block size, making it impossible to
251 		 * tie more than one memory buffer with single SDIO block.
252 		 * Block mode sg buffer size should be aligned with SDIO block
253 		 * size, otherwise chain mode could not be used.
254 		 */
255 		for_each_sg(data->sg, sg, data->sg_len, i) {
256 			if (sg->length % data->blksz) {
257 				dev_warn_once(mmc_dev(mmc),
258 					      "unaligned sg len %u blksize %u, disabling descriptor DMA for transfer\n",
259 					      sg->length, data->blksz);
260 				return;
261 			}
262 		}
263 	}
264 
265 	for_each_sg(data->sg, sg, data->sg_len, i) {
266 		/* check for 8 byte alignment */
267 		if (sg->offset % 8) {
268 			dev_warn_once(mmc_dev(mmc),
269 				      "unaligned sg offset %u, disabling descriptor DMA for transfer\n",
270 				      sg->offset);
271 			return;
272 		}
273 	}
274 
275 	data->host_cookie |= SD_EMMC_DESC_CHAIN_MODE;
276 }
277 
278 static inline bool meson_mmc_desc_chain_mode(const struct mmc_data *data)
279 {
280 	return data->host_cookie & SD_EMMC_DESC_CHAIN_MODE;
281 }
282 
283 static inline bool meson_mmc_bounce_buf_read(const struct mmc_data *data)
284 {
285 	return data && data->flags & MMC_DATA_READ &&
286 	       !meson_mmc_desc_chain_mode(data);
287 }
288 
289 static void meson_mmc_pre_req(struct mmc_host *mmc, struct mmc_request *mrq)
290 {
291 	struct mmc_data *data = mrq->data;
292 
293 	if (!data)
294 		return;
295 
296 	meson_mmc_get_transfer_mode(mmc, mrq);
297 	data->host_cookie |= SD_EMMC_PRE_REQ_DONE;
298 
299 	if (!meson_mmc_desc_chain_mode(data))
300 		return;
301 
302 	data->sg_count = dma_map_sg(mmc_dev(mmc), data->sg, data->sg_len,
303                                    mmc_get_dma_dir(data));
304 	if (!data->sg_count)
305 		dev_err(mmc_dev(mmc), "dma_map_sg failed");
306 }
307 
308 static void meson_mmc_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
309 			       int err)
310 {
311 	struct mmc_data *data = mrq->data;
312 
313 	if (data && meson_mmc_desc_chain_mode(data) && data->sg_count)
314 		dma_unmap_sg(mmc_dev(mmc), data->sg, data->sg_len,
315 			     mmc_get_dma_dir(data));
316 }
317 
318 /*
319  * Gating the clock on this controller is tricky.  It seems the mmc clock
320  * is also used by the controller.  It may crash during some operation if the
321  * clock is stopped.  The safest thing to do, whenever possible, is to keep
322  * clock running at stop it at the pad using the pinmux.
323  */
324 static void meson_mmc_clk_gate(struct meson_host *host)
325 {
326 	u32 cfg;
327 
328 	if (host->pins_clk_gate) {
329 		pinctrl_select_state(host->pinctrl, host->pins_clk_gate);
330 	} else {
331 		/*
332 		 * If the pinmux is not provided - default to the classic and
333 		 * unsafe method
334 		 */
335 		cfg = readl(host->regs + SD_EMMC_CFG);
336 		cfg |= CFG_STOP_CLOCK;
337 		writel(cfg, host->regs + SD_EMMC_CFG);
338 	}
339 }
340 
341 static void meson_mmc_clk_ungate(struct meson_host *host)
342 {
343 	u32 cfg;
344 
345 	if (host->pins_clk_gate)
346 		pinctrl_select_default_state(host->dev);
347 
348 	/* Make sure the clock is not stopped in the controller */
349 	cfg = readl(host->regs + SD_EMMC_CFG);
350 	cfg &= ~CFG_STOP_CLOCK;
351 	writel(cfg, host->regs + SD_EMMC_CFG);
352 }
353 
354 static int meson_mmc_clk_set(struct meson_host *host, unsigned long rate,
355 			     bool ddr)
356 {
357 	struct mmc_host *mmc = host->mmc;
358 	int ret;
359 	u32 cfg;
360 
361 	/* Same request - bail-out */
362 	if (host->ddr == ddr && host->req_rate == rate)
363 		return 0;
364 
365 	/* stop clock */
366 	meson_mmc_clk_gate(host);
367 	host->req_rate = 0;
368 	mmc->actual_clock = 0;
369 
370 	/* return with clock being stopped */
371 	if (!rate)
372 		return 0;
373 
374 	/* Stop the clock during rate change to avoid glitches */
375 	cfg = readl(host->regs + SD_EMMC_CFG);
376 	cfg |= CFG_STOP_CLOCK;
377 	writel(cfg, host->regs + SD_EMMC_CFG);
378 
379 	if (ddr) {
380 		/* DDR modes require higher module clock */
381 		rate <<= 1;
382 		cfg |= CFG_DDR;
383 	} else {
384 		cfg &= ~CFG_DDR;
385 	}
386 	writel(cfg, host->regs + SD_EMMC_CFG);
387 	host->ddr = ddr;
388 
389 	ret = clk_set_rate(host->mmc_clk, rate);
390 	if (ret) {
391 		dev_err(host->dev, "Unable to set cfg_div_clk to %lu. ret=%d\n",
392 			rate, ret);
393 		return ret;
394 	}
395 
396 	host->req_rate = rate;
397 	mmc->actual_clock = clk_get_rate(host->mmc_clk);
398 
399 	/* We should report the real output frequency of the controller */
400 	if (ddr) {
401 		host->req_rate >>= 1;
402 		mmc->actual_clock >>= 1;
403 	}
404 
405 	dev_dbg(host->dev, "clk rate: %u Hz\n", mmc->actual_clock);
406 	if (rate != mmc->actual_clock)
407 		dev_dbg(host->dev, "requested rate was %lu\n", rate);
408 
409 	/* (re)start clock */
410 	meson_mmc_clk_ungate(host);
411 
412 	return 0;
413 }
414 
415 /*
416  * The SD/eMMC IP block has an internal mux and divider used for
417  * generating the MMC clock.  Use the clock framework to create and
418  * manage these clocks.
419  */
420 static int meson_mmc_clk_init(struct meson_host *host)
421 {
422 	struct clk_init_data init;
423 	struct clk_mux *mux;
424 	struct clk_divider *div;
425 	char clk_name[32];
426 	int i, ret = 0;
427 	const char *mux_parent_names[MUX_CLK_NUM_PARENTS];
428 	const char *clk_parent[1];
429 	u32 clk_reg;
430 
431 	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
432 	clk_reg = CLK_ALWAYS_ON(host);
433 	clk_reg |= CLK_DIV_MASK;
434 	clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, CLK_PHASE_180);
435 	clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, CLK_PHASE_0);
436 	clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, CLK_PHASE_0);
437 	if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
438 		clk_reg |= CLK_IRQ_SDIO_SLEEP(host);
439 	writel(clk_reg, host->regs + SD_EMMC_CLOCK);
440 
441 	/* get the mux parents */
442 	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
443 		struct clk *clk;
444 		char name[16];
445 
446 		snprintf(name, sizeof(name), "clkin%d", i);
447 		clk = devm_clk_get(host->dev, name);
448 		if (IS_ERR(clk))
449 			return dev_err_probe(host->dev, PTR_ERR(clk),
450 					     "Missing clock %s\n", name);
451 
452 		mux_parent_names[i] = __clk_get_name(clk);
453 	}
454 
455 	/* create the mux */
456 	mux = devm_kzalloc(host->dev, sizeof(*mux), GFP_KERNEL);
457 	if (!mux)
458 		return -ENOMEM;
459 
460 	snprintf(clk_name, sizeof(clk_name), "%s#mux", dev_name(host->dev));
461 	init.name = clk_name;
462 	init.ops = &clk_mux_ops;
463 	init.flags = 0;
464 	init.parent_names = mux_parent_names;
465 	init.num_parents = MUX_CLK_NUM_PARENTS;
466 
467 	mux->reg = host->regs + SD_EMMC_CLOCK;
468 	mux->shift = __ffs(CLK_SRC_MASK);
469 	mux->mask = CLK_SRC_MASK >> mux->shift;
470 	mux->hw.init = &init;
471 
472 	host->mux_clk = devm_clk_register(host->dev, &mux->hw);
473 	if (WARN_ON(IS_ERR(host->mux_clk)))
474 		return PTR_ERR(host->mux_clk);
475 
476 	/* create the divider */
477 	div = devm_kzalloc(host->dev, sizeof(*div), GFP_KERNEL);
478 	if (!div)
479 		return -ENOMEM;
480 
481 	snprintf(clk_name, sizeof(clk_name), "%s#div", dev_name(host->dev));
482 	init.name = clk_name;
483 	init.ops = &clk_divider_ops;
484 	init.flags = CLK_SET_RATE_PARENT;
485 	clk_parent[0] = __clk_get_name(host->mux_clk);
486 	init.parent_names = clk_parent;
487 	init.num_parents = 1;
488 
489 	div->reg = host->regs + SD_EMMC_CLOCK;
490 	div->shift = __ffs(CLK_DIV_MASK);
491 	div->width = __builtin_popcountl(CLK_DIV_MASK);
492 	div->hw.init = &init;
493 	div->flags = CLK_DIVIDER_ONE_BASED;
494 
495 	host->mmc_clk = devm_clk_register(host->dev, &div->hw);
496 	if (WARN_ON(IS_ERR(host->mmc_clk)))
497 		return PTR_ERR(host->mmc_clk);
498 
499 	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
500 	host->mmc->f_min = clk_round_rate(host->mmc_clk, 400000);
501 	ret = clk_set_rate(host->mmc_clk, host->mmc->f_min);
502 	if (ret)
503 		return ret;
504 
505 	return clk_prepare_enable(host->mmc_clk);
506 }
507 
508 static void meson_mmc_disable_resampling(struct meson_host *host)
509 {
510 	unsigned int val = readl(host->regs + host->data->adjust);
511 
512 	val &= ~ADJUST_ADJ_EN;
513 	writel(val, host->regs + host->data->adjust);
514 }
515 
516 static void meson_mmc_reset_resampling(struct meson_host *host)
517 {
518 	unsigned int val;
519 
520 	meson_mmc_disable_resampling(host);
521 
522 	val = readl(host->regs + host->data->adjust);
523 	val &= ~ADJUST_ADJ_DELAY_MASK;
524 	writel(val, host->regs + host->data->adjust);
525 }
526 
527 static int meson_mmc_resampling_tuning(struct mmc_host *mmc, u32 opcode)
528 {
529 	struct meson_host *host = mmc_priv(mmc);
530 	unsigned int val, dly, max_dly, i;
531 	int ret;
532 
533 	/* Resampling is done using the source clock */
534 	max_dly = DIV_ROUND_UP(clk_get_rate(host->mux_clk),
535 			       clk_get_rate(host->mmc_clk));
536 
537 	val = readl(host->regs + host->data->adjust);
538 	val |= ADJUST_ADJ_EN;
539 	writel(val, host->regs + host->data->adjust);
540 
541 	if (mmc_doing_retune(mmc))
542 		dly = FIELD_GET(ADJUST_ADJ_DELAY_MASK, val) + 1;
543 	else
544 		dly = 0;
545 
546 	for (i = 0; i < max_dly; i++) {
547 		val &= ~ADJUST_ADJ_DELAY_MASK;
548 		val |= FIELD_PREP(ADJUST_ADJ_DELAY_MASK, (dly + i) % max_dly);
549 		writel(val, host->regs + host->data->adjust);
550 
551 		ret = mmc_send_tuning(mmc, opcode, NULL);
552 		if (!ret) {
553 			dev_dbg(mmc_dev(mmc), "resampling delay: %u\n",
554 				(dly + i) % max_dly);
555 			return 0;
556 		}
557 	}
558 
559 	meson_mmc_reset_resampling(host);
560 	return -EIO;
561 }
562 
563 static int meson_mmc_prepare_ios_clock(struct meson_host *host,
564 				       struct mmc_ios *ios)
565 {
566 	bool ddr;
567 
568 	switch (ios->timing) {
569 	case MMC_TIMING_MMC_DDR52:
570 	case MMC_TIMING_UHS_DDR50:
571 		ddr = true;
572 		break;
573 
574 	default:
575 		ddr = false;
576 		break;
577 	}
578 
579 	return meson_mmc_clk_set(host, ios->clock, ddr);
580 }
581 
582 static void meson_mmc_check_resampling(struct meson_host *host,
583 				       struct mmc_ios *ios)
584 {
585 	switch (ios->timing) {
586 	case MMC_TIMING_LEGACY:
587 	case MMC_TIMING_MMC_HS:
588 	case MMC_TIMING_SD_HS:
589 	case MMC_TIMING_MMC_DDR52:
590 		meson_mmc_disable_resampling(host);
591 		break;
592 	}
593 }
594 
595 static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
596 {
597 	struct meson_host *host = mmc_priv(mmc);
598 	u32 bus_width, val;
599 	int err;
600 
601 	/*
602 	 * GPIO regulator, only controls switching between 1v8 and
603 	 * 3v3, doesn't support MMC_POWER_OFF, MMC_POWER_ON.
604 	 */
605 	switch (ios->power_mode) {
606 	case MMC_POWER_OFF:
607 		if (!IS_ERR(mmc->supply.vmmc))
608 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
609 
610 		if (!IS_ERR(mmc->supply.vqmmc) && host->vqmmc_enabled) {
611 			regulator_disable(mmc->supply.vqmmc);
612 			host->vqmmc_enabled = false;
613 		}
614 
615 		break;
616 
617 	case MMC_POWER_UP:
618 		if (!IS_ERR(mmc->supply.vmmc))
619 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
620 
621 		break;
622 
623 	case MMC_POWER_ON:
624 		if (!IS_ERR(mmc->supply.vqmmc) && !host->vqmmc_enabled) {
625 			int ret = regulator_enable(mmc->supply.vqmmc);
626 
627 			if (ret < 0)
628 				dev_err(host->dev,
629 					"failed to enable vqmmc regulator\n");
630 			else
631 				host->vqmmc_enabled = true;
632 		}
633 
634 		break;
635 	}
636 
637 	/* Bus width */
638 	switch (ios->bus_width) {
639 	case MMC_BUS_WIDTH_1:
640 		bus_width = CFG_BUS_WIDTH_1;
641 		break;
642 	case MMC_BUS_WIDTH_4:
643 		bus_width = CFG_BUS_WIDTH_4;
644 		break;
645 	case MMC_BUS_WIDTH_8:
646 		bus_width = CFG_BUS_WIDTH_8;
647 		break;
648 	default:
649 		dev_err(host->dev, "Invalid ios->bus_width: %u.  Setting to 4.\n",
650 			ios->bus_width);
651 		bus_width = CFG_BUS_WIDTH_4;
652 	}
653 
654 	val = readl(host->regs + SD_EMMC_CFG);
655 	val &= ~CFG_BUS_WIDTH_MASK;
656 	val |= FIELD_PREP(CFG_BUS_WIDTH_MASK, bus_width);
657 	writel(val, host->regs + SD_EMMC_CFG);
658 
659 	meson_mmc_check_resampling(host, ios);
660 	err = meson_mmc_prepare_ios_clock(host, ios);
661 	if (err)
662 		dev_err(host->dev, "Failed to set clock: %d\n,", err);
663 
664 	dev_dbg(host->dev, "SD_EMMC_CFG:  0x%08x\n", val);
665 }
666 
667 static void meson_mmc_request_done(struct mmc_host *mmc,
668 				   struct mmc_request *mrq)
669 {
670 	struct meson_host *host = mmc_priv(mmc);
671 
672 	host->cmd = NULL;
673 	if (host->needs_pre_post_req)
674 		meson_mmc_post_req(mmc, mrq, 0);
675 	mmc_request_done(host->mmc, mrq);
676 }
677 
678 static void meson_mmc_set_blksz(struct mmc_host *mmc, unsigned int blksz)
679 {
680 	struct meson_host *host = mmc_priv(mmc);
681 	u32 cfg, blksz_old;
682 
683 	cfg = readl(host->regs + SD_EMMC_CFG);
684 	blksz_old = FIELD_GET(CFG_BLK_LEN_MASK, cfg);
685 
686 	if (!is_power_of_2(blksz))
687 		dev_err(host->dev, "blksz %u is not a power of 2\n", blksz);
688 
689 	blksz = ilog2(blksz);
690 
691 	/* check if block-size matches, if not update */
692 	if (blksz == blksz_old)
693 		return;
694 
695 	dev_dbg(host->dev, "%s: update blk_len %d -> %d\n", __func__,
696 		blksz_old, blksz);
697 
698 	cfg &= ~CFG_BLK_LEN_MASK;
699 	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, blksz);
700 	writel(cfg, host->regs + SD_EMMC_CFG);
701 }
702 
703 static void meson_mmc_set_response_bits(struct mmc_command *cmd, u32 *cmd_cfg)
704 {
705 	if (cmd->flags & MMC_RSP_PRESENT) {
706 		if (cmd->flags & MMC_RSP_136)
707 			*cmd_cfg |= CMD_CFG_RESP_128;
708 		*cmd_cfg |= CMD_CFG_RESP_NUM;
709 
710 		if (!(cmd->flags & MMC_RSP_CRC))
711 			*cmd_cfg |= CMD_CFG_RESP_NOCRC;
712 
713 		if (cmd->flags & MMC_RSP_BUSY)
714 			*cmd_cfg |= CMD_CFG_R1B;
715 	} else {
716 		*cmd_cfg |= CMD_CFG_NO_RESP;
717 	}
718 }
719 
720 static void meson_mmc_desc_chain_transfer(struct mmc_host *mmc, u32 cmd_cfg)
721 {
722 	struct meson_host *host = mmc_priv(mmc);
723 	struct sd_emmc_desc *desc = host->descs;
724 	struct mmc_data *data = host->cmd->data;
725 	struct scatterlist *sg;
726 	u32 start;
727 	int i;
728 
729 	if (data->flags & MMC_DATA_WRITE)
730 		cmd_cfg |= CMD_CFG_DATA_WR;
731 
732 	if (data->blocks > 1) {
733 		cmd_cfg |= CMD_CFG_BLOCK_MODE;
734 		meson_mmc_set_blksz(mmc, data->blksz);
735 	}
736 
737 	for_each_sg(data->sg, sg, data->sg_count, i) {
738 		unsigned int len = sg_dma_len(sg);
739 
740 		if (data->blocks > 1)
741 			len /= data->blksz;
742 
743 		desc[i].cmd_cfg = cmd_cfg;
744 		desc[i].cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, len);
745 		if (i > 0)
746 			desc[i].cmd_cfg |= CMD_CFG_NO_CMD;
747 		desc[i].cmd_arg = host->cmd->arg;
748 		desc[i].cmd_resp = 0;
749 		desc[i].cmd_data = sg_dma_address(sg);
750 	}
751 	desc[data->sg_count - 1].cmd_cfg |= CMD_CFG_END_OF_CHAIN;
752 
753 	dma_wmb(); /* ensure descriptor is written before kicked */
754 	start = host->descs_dma_addr | START_DESC_BUSY;
755 	writel(start, host->regs + SD_EMMC_START);
756 }
757 
758 /* local sg copy for dram_access_quirk */
759 static void meson_mmc_copy_buffer(struct meson_host *host, struct mmc_data *data,
760 				  size_t buflen, bool to_buffer)
761 {
762 	unsigned int sg_flags = SG_MITER_ATOMIC;
763 	struct scatterlist *sgl = data->sg;
764 	unsigned int nents = data->sg_len;
765 	struct sg_mapping_iter miter;
766 	unsigned int offset = 0;
767 
768 	if (to_buffer)
769 		sg_flags |= SG_MITER_FROM_SG;
770 	else
771 		sg_flags |= SG_MITER_TO_SG;
772 
773 	sg_miter_start(&miter, sgl, nents, sg_flags);
774 
775 	while ((offset < buflen) && sg_miter_next(&miter)) {
776 		unsigned int buf_offset = 0;
777 		unsigned int len, left;
778 		u32 *buf = miter.addr;
779 
780 		len = min(miter.length, buflen - offset);
781 		left = len;
782 
783 		if (to_buffer) {
784 			do {
785 				writel(*buf++, host->bounce_iomem_buf + offset + buf_offset);
786 
787 				buf_offset += 4;
788 				left -= 4;
789 			} while (left);
790 		} else {
791 			do {
792 				*buf++ = readl(host->bounce_iomem_buf + offset + buf_offset);
793 
794 				buf_offset += 4;
795 				left -= 4;
796 			} while (left);
797 		}
798 
799 		offset += len;
800 	}
801 
802 	sg_miter_stop(&miter);
803 }
804 
805 static void meson_mmc_start_cmd(struct mmc_host *mmc, struct mmc_command *cmd)
806 {
807 	struct meson_host *host = mmc_priv(mmc);
808 	struct mmc_data *data = cmd->data;
809 	u32 cmd_cfg = 0, cmd_data = 0;
810 	unsigned int xfer_bytes = 0;
811 
812 	/* Setup descriptors */
813 	dma_rmb();
814 
815 	host->cmd = cmd;
816 
817 	cmd_cfg |= FIELD_PREP(CMD_CFG_CMD_INDEX_MASK, cmd->opcode);
818 	cmd_cfg |= CMD_CFG_OWNER;  /* owned by CPU */
819 	cmd_cfg |= CMD_CFG_ERROR; /* stop in case of error */
820 
821 	meson_mmc_set_response_bits(cmd, &cmd_cfg);
822 
823 	/* data? */
824 	if (data) {
825 		data->bytes_xfered = 0;
826 		cmd_cfg |= CMD_CFG_DATA_IO;
827 		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
828 				      ilog2(meson_mmc_get_timeout_msecs(data)));
829 
830 		if (meson_mmc_desc_chain_mode(data)) {
831 			meson_mmc_desc_chain_transfer(mmc, cmd_cfg);
832 			return;
833 		}
834 
835 		if (data->blocks > 1) {
836 			cmd_cfg |= CMD_CFG_BLOCK_MODE;
837 			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK,
838 					      data->blocks);
839 			meson_mmc_set_blksz(mmc, data->blksz);
840 		} else {
841 			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, data->blksz);
842 		}
843 
844 		xfer_bytes = data->blksz * data->blocks;
845 		if (data->flags & MMC_DATA_WRITE) {
846 			cmd_cfg |= CMD_CFG_DATA_WR;
847 			WARN_ON(xfer_bytes > host->bounce_buf_size);
848 			if (host->dram_access_quirk)
849 				meson_mmc_copy_buffer(host, data, xfer_bytes, true);
850 			else
851 				sg_copy_to_buffer(data->sg, data->sg_len,
852 						  host->bounce_buf, xfer_bytes);
853 			dma_wmb();
854 		}
855 
856 		cmd_data = host->bounce_dma_addr & CMD_DATA_MASK;
857 	} else {
858 		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
859 				      ilog2(SD_EMMC_CMD_TIMEOUT));
860 	}
861 
862 	/* Last descriptor */
863 	cmd_cfg |= CMD_CFG_END_OF_CHAIN;
864 	writel(cmd_cfg, host->regs + SD_EMMC_CMD_CFG);
865 	writel(cmd_data, host->regs + SD_EMMC_CMD_DAT);
866 	writel(0, host->regs + SD_EMMC_CMD_RSP);
867 	wmb(); /* ensure descriptor is written before kicked */
868 	writel(cmd->arg, host->regs + SD_EMMC_CMD_ARG);
869 }
870 
871 static int meson_mmc_validate_dram_access(struct mmc_host *mmc, struct mmc_data *data)
872 {
873 	struct scatterlist *sg;
874 	int i;
875 
876 	/* Reject request if any element offset or size is not 32bit aligned */
877 	for_each_sg(data->sg, sg, data->sg_len, i) {
878 		if (!IS_ALIGNED(sg->offset, sizeof(u32)) ||
879 		    !IS_ALIGNED(sg->length, sizeof(u32))) {
880 			dev_err(mmc_dev(mmc), "unaligned sg offset %u len %u\n",
881 				data->sg->offset, data->sg->length);
882 			return -EINVAL;
883 		}
884 	}
885 
886 	return 0;
887 }
888 
889 static void meson_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
890 {
891 	struct meson_host *host = mmc_priv(mmc);
892 	host->needs_pre_post_req = mrq->data &&
893 			!(mrq->data->host_cookie & SD_EMMC_PRE_REQ_DONE);
894 
895 	/*
896 	 * The memory at the end of the controller used as bounce buffer for
897 	 * the dram_access_quirk only accepts 32bit read/write access,
898 	 * check the aligment and length of the data before starting the request.
899 	 */
900 	if (host->dram_access_quirk && mrq->data) {
901 		mrq->cmd->error = meson_mmc_validate_dram_access(mmc, mrq->data);
902 		if (mrq->cmd->error) {
903 			mmc_request_done(mmc, mrq);
904 			return;
905 		}
906 	}
907 
908 	if (host->needs_pre_post_req) {
909 		meson_mmc_get_transfer_mode(mmc, mrq);
910 		if (!meson_mmc_desc_chain_mode(mrq->data))
911 			host->needs_pre_post_req = false;
912 	}
913 
914 	if (host->needs_pre_post_req)
915 		meson_mmc_pre_req(mmc, mrq);
916 
917 	/* Stop execution */
918 	writel(0, host->regs + SD_EMMC_START);
919 
920 	meson_mmc_start_cmd(mmc, mrq->sbc ?: mrq->cmd);
921 }
922 
923 static void meson_mmc_read_resp(struct mmc_host *mmc, struct mmc_command *cmd)
924 {
925 	struct meson_host *host = mmc_priv(mmc);
926 
927 	if (cmd->flags & MMC_RSP_136) {
928 		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP3);
929 		cmd->resp[1] = readl(host->regs + SD_EMMC_CMD_RSP2);
930 		cmd->resp[2] = readl(host->regs + SD_EMMC_CMD_RSP1);
931 		cmd->resp[3] = readl(host->regs + SD_EMMC_CMD_RSP);
932 	} else if (cmd->flags & MMC_RSP_PRESENT) {
933 		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP);
934 	}
935 }
936 
937 static void __meson_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
938 {
939 	struct meson_host *host = mmc_priv(mmc);
940 	u32 reg_irqen = IRQ_EN_MASK;
941 
942 	if (enable)
943 		reg_irqen |= IRQ_SDIO;
944 	writel(reg_irqen, host->regs + SD_EMMC_IRQ_EN);
945 }
946 
947 static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
948 {
949 	struct meson_host *host = dev_id;
950 	struct mmc_command *cmd;
951 	u32 status, raw_status, irq_mask = IRQ_EN_MASK;
952 	irqreturn_t ret = IRQ_NONE;
953 
954 	if (host->mmc->caps & MMC_CAP_SDIO_IRQ)
955 		irq_mask |= IRQ_SDIO;
956 	raw_status = readl(host->regs + SD_EMMC_STATUS);
957 	status = raw_status & irq_mask;
958 
959 	if (!status) {
960 		dev_dbg(host->dev,
961 			"Unexpected IRQ! irq_en 0x%08x - status 0x%08x\n",
962 			 irq_mask, raw_status);
963 		return IRQ_NONE;
964 	}
965 
966 	if (WARN_ON(!host))
967 		return IRQ_NONE;
968 
969 	/* ack all raised interrupts */
970 	writel(status, host->regs + SD_EMMC_STATUS);
971 
972 	cmd = host->cmd;
973 
974 	if (status & IRQ_SDIO) {
975 		spin_lock(&host->lock);
976 		__meson_mmc_enable_sdio_irq(host->mmc, 0);
977 		sdio_signal_irq(host->mmc);
978 		spin_unlock(&host->lock);
979 		status &= ~IRQ_SDIO;
980 		if (!status)
981 			return IRQ_HANDLED;
982 	}
983 
984 	if (WARN_ON(!cmd))
985 		return IRQ_NONE;
986 
987 	cmd->error = 0;
988 	if (status & IRQ_CRC_ERR) {
989 		dev_dbg(host->dev, "CRC Error - status 0x%08x\n", status);
990 		cmd->error = -EILSEQ;
991 		ret = IRQ_WAKE_THREAD;
992 		goto out;
993 	}
994 
995 	if (status & IRQ_TIMEOUTS) {
996 		dev_dbg(host->dev, "Timeout - status 0x%08x\n", status);
997 		cmd->error = -ETIMEDOUT;
998 		ret = IRQ_WAKE_THREAD;
999 		goto out;
1000 	}
1001 
1002 	meson_mmc_read_resp(host->mmc, cmd);
1003 
1004 	if (status & (IRQ_END_OF_CHAIN | IRQ_RESP_STATUS)) {
1005 		struct mmc_data *data = cmd->data;
1006 
1007 		if (data && !cmd->error)
1008 			data->bytes_xfered = data->blksz * data->blocks;
1009 		if (meson_mmc_bounce_buf_read(data) ||
1010 		    meson_mmc_get_next_command(cmd))
1011 			ret = IRQ_WAKE_THREAD;
1012 		else
1013 			ret = IRQ_HANDLED;
1014 	}
1015 
1016 out:
1017 	if (cmd->error) {
1018 		/* Stop desc in case of errors */
1019 		u32 start = readl(host->regs + SD_EMMC_START);
1020 
1021 		start &= ~START_DESC_BUSY;
1022 		writel(start, host->regs + SD_EMMC_START);
1023 	}
1024 
1025 	if (ret == IRQ_HANDLED)
1026 		meson_mmc_request_done(host->mmc, cmd->mrq);
1027 
1028 	return ret;
1029 }
1030 
1031 static int meson_mmc_wait_desc_stop(struct meson_host *host)
1032 {
1033 	u32 status;
1034 
1035 	/*
1036 	 * It may sometimes take a while for it to actually halt. Here, we
1037 	 * are giving it 5ms to comply
1038 	 *
1039 	 * If we don't confirm the descriptor is stopped, it might raise new
1040 	 * IRQs after we have called mmc_request_done() which is bad.
1041 	 */
1042 
1043 	return readl_poll_timeout(host->regs + SD_EMMC_STATUS, status,
1044 				  !(status & (STATUS_BUSY | STATUS_DESC_BUSY)),
1045 				  100, 5000);
1046 }
1047 
1048 static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id)
1049 {
1050 	struct meson_host *host = dev_id;
1051 	struct mmc_command *next_cmd, *cmd = host->cmd;
1052 	struct mmc_data *data;
1053 	unsigned int xfer_bytes;
1054 
1055 	if (WARN_ON(!cmd))
1056 		return IRQ_NONE;
1057 
1058 	if (cmd->error) {
1059 		meson_mmc_wait_desc_stop(host);
1060 		meson_mmc_request_done(host->mmc, cmd->mrq);
1061 
1062 		return IRQ_HANDLED;
1063 	}
1064 
1065 	data = cmd->data;
1066 	if (meson_mmc_bounce_buf_read(data)) {
1067 		xfer_bytes = data->blksz * data->blocks;
1068 		WARN_ON(xfer_bytes > host->bounce_buf_size);
1069 		if (host->dram_access_quirk)
1070 			meson_mmc_copy_buffer(host, data, xfer_bytes, false);
1071 		else
1072 			sg_copy_from_buffer(data->sg, data->sg_len,
1073 					    host->bounce_buf, xfer_bytes);
1074 	}
1075 
1076 	next_cmd = meson_mmc_get_next_command(cmd);
1077 	if (next_cmd)
1078 		meson_mmc_start_cmd(host->mmc, next_cmd);
1079 	else
1080 		meson_mmc_request_done(host->mmc, cmd->mrq);
1081 
1082 	return IRQ_HANDLED;
1083 }
1084 
1085 static void meson_mmc_cfg_init(struct meson_host *host)
1086 {
1087 	u32 cfg = 0;
1088 
1089 	cfg |= FIELD_PREP(CFG_RESP_TIMEOUT_MASK,
1090 			  ilog2(SD_EMMC_CFG_RESP_TIMEOUT));
1091 	cfg |= FIELD_PREP(CFG_RC_CC_MASK, ilog2(SD_EMMC_CFG_CMD_GAP));
1092 	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, ilog2(SD_EMMC_CFG_BLK_SIZE));
1093 
1094 	/* abort chain on R/W errors */
1095 	cfg |= CFG_ERR_ABORT;
1096 
1097 	writel(cfg, host->regs + SD_EMMC_CFG);
1098 }
1099 
1100 static int meson_mmc_card_busy(struct mmc_host *mmc)
1101 {
1102 	struct meson_host *host = mmc_priv(mmc);
1103 	u32 regval;
1104 
1105 	regval = readl(host->regs + SD_EMMC_STATUS);
1106 
1107 	/* We are only interrested in lines 0 to 3, so mask the other ones */
1108 	return !(FIELD_GET(STATUS_DATI, regval) & 0xf);
1109 }
1110 
1111 static int meson_mmc_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
1112 {
1113 	int ret;
1114 
1115 	/* vqmmc regulator is available */
1116 	if (!IS_ERR(mmc->supply.vqmmc)) {
1117 		/*
1118 		 * The usual amlogic setup uses a GPIO to switch from one
1119 		 * regulator to the other. While the voltage ramp up is
1120 		 * pretty fast, care must be taken when switching from 3.3v
1121 		 * to 1.8v. Please make sure the regulator framework is aware
1122 		 * of your own regulator constraints
1123 		 */
1124 		ret = mmc_regulator_set_vqmmc(mmc, ios);
1125 		return ret < 0 ? ret : 0;
1126 	}
1127 
1128 	/* no vqmmc regulator, assume fixed regulator at 3/3.3V */
1129 	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
1130 		return 0;
1131 
1132 	return -EINVAL;
1133 }
1134 
1135 static void meson_mmc_enable_sdio_irq(struct mmc_host *mmc, int enable)
1136 {
1137 	struct meson_host *host = mmc_priv(mmc);
1138 	unsigned long flags;
1139 
1140 	spin_lock_irqsave(&host->lock, flags);
1141 	__meson_mmc_enable_sdio_irq(mmc, enable);
1142 	spin_unlock_irqrestore(&host->lock, flags);
1143 }
1144 
1145 static void meson_mmc_ack_sdio_irq(struct mmc_host *mmc)
1146 {
1147 	meson_mmc_enable_sdio_irq(mmc, 1);
1148 }
1149 
1150 static const struct mmc_host_ops meson_mmc_ops = {
1151 	.request	= meson_mmc_request,
1152 	.set_ios	= meson_mmc_set_ios,
1153 	.get_cd         = mmc_gpio_get_cd,
1154 	.pre_req	= meson_mmc_pre_req,
1155 	.post_req	= meson_mmc_post_req,
1156 	.execute_tuning = meson_mmc_resampling_tuning,
1157 	.card_busy	= meson_mmc_card_busy,
1158 	.start_signal_voltage_switch = meson_mmc_voltage_switch,
1159 	.enable_sdio_irq = meson_mmc_enable_sdio_irq,
1160 	.ack_sdio_irq	= meson_mmc_ack_sdio_irq,
1161 };
1162 
1163 static int meson_mmc_probe(struct platform_device *pdev)
1164 {
1165 	struct resource *res;
1166 	struct meson_host *host;
1167 	struct mmc_host *mmc;
1168 	struct clk *core_clk;
1169 	int cd_irq, ret;
1170 
1171 	mmc = devm_mmc_alloc_host(&pdev->dev, sizeof(struct meson_host));
1172 	if (!mmc)
1173 		return -ENOMEM;
1174 	host = mmc_priv(mmc);
1175 	host->mmc = mmc;
1176 	host->dev = &pdev->dev;
1177 	dev_set_drvdata(&pdev->dev, host);
1178 
1179 	/* The G12A SDIO Controller needs an SRAM bounce buffer */
1180 	host->dram_access_quirk = device_property_read_bool(&pdev->dev,
1181 					"amlogic,dram-access-quirk");
1182 
1183 	/* Get regulators and the supported OCR mask */
1184 	host->vqmmc_enabled = false;
1185 	ret = mmc_regulator_get_supply(mmc);
1186 	if (ret)
1187 		return ret;
1188 
1189 	ret = mmc_of_parse(mmc);
1190 	if (ret)
1191 		return dev_err_probe(&pdev->dev, ret, "error parsing DT\n");
1192 
1193 	mmc->caps |= MMC_CAP_CMD23;
1194 
1195 	if (mmc->caps & MMC_CAP_SDIO_IRQ)
1196 		mmc->caps2 |= MMC_CAP2_SDIO_IRQ_NOTHREAD;
1197 
1198 	host->data = of_device_get_match_data(&pdev->dev);
1199 	if (!host->data)
1200 		return -EINVAL;
1201 
1202 	ret = device_reset_optional(&pdev->dev);
1203 	if (ret)
1204 		return dev_err_probe(&pdev->dev, ret, "device reset failed\n");
1205 
1206 	host->regs = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
1207 	if (IS_ERR(host->regs))
1208 		return PTR_ERR(host->regs);
1209 
1210 	host->irq = platform_get_irq(pdev, 0);
1211 	if (host->irq <= 0)
1212 		return -EINVAL;
1213 
1214 	cd_irq = platform_get_irq_optional(pdev, 1);
1215 	mmc_gpio_set_cd_irq(mmc, cd_irq);
1216 
1217 	host->pinctrl = devm_pinctrl_get(&pdev->dev);
1218 	if (IS_ERR(host->pinctrl))
1219 		return PTR_ERR(host->pinctrl);
1220 
1221 	host->pins_clk_gate = pinctrl_lookup_state(host->pinctrl,
1222 						   "clk-gate");
1223 	if (IS_ERR(host->pins_clk_gate)) {
1224 		dev_warn(&pdev->dev,
1225 			 "can't get clk-gate pinctrl, using clk_stop bit\n");
1226 		host->pins_clk_gate = NULL;
1227 	}
1228 
1229 	core_clk = devm_clk_get_enabled(&pdev->dev, "core");
1230 	if (IS_ERR(core_clk))
1231 		return PTR_ERR(core_clk);
1232 
1233 	ret = meson_mmc_clk_init(host);
1234 	if (ret)
1235 		return ret;
1236 
1237 	/* set config to sane default */
1238 	meson_mmc_cfg_init(host);
1239 
1240 	/* Stop execution */
1241 	writel(0, host->regs + SD_EMMC_START);
1242 
1243 	/* clear, ack and enable interrupts */
1244 	writel(0, host->regs + SD_EMMC_IRQ_EN);
1245 	writel(IRQ_EN_MASK, host->regs + SD_EMMC_STATUS);
1246 	writel(IRQ_EN_MASK, host->regs + SD_EMMC_IRQ_EN);
1247 
1248 	ret = request_threaded_irq(host->irq, meson_mmc_irq,
1249 				   meson_mmc_irq_thread, IRQF_ONESHOT,
1250 				   dev_name(&pdev->dev), host);
1251 	if (ret)
1252 		goto err_init_clk;
1253 
1254 	spin_lock_init(&host->lock);
1255 
1256 	if (host->dram_access_quirk) {
1257 		/* Limit segments to 1 due to low available sram memory */
1258 		mmc->max_segs = 1;
1259 		/* Limit to the available sram memory */
1260 		mmc->max_blk_count = SD_EMMC_SRAM_DATA_BUF_LEN /
1261 				     mmc->max_blk_size;
1262 	} else {
1263 		mmc->max_blk_count = CMD_CFG_LENGTH_MASK;
1264 		mmc->max_segs = SD_EMMC_DESC_BUF_LEN /
1265 				sizeof(struct sd_emmc_desc);
1266 	}
1267 	mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
1268 	mmc->max_seg_size = mmc->max_req_size;
1269 
1270 	/*
1271 	 * At the moment, we don't know how to reliably enable HS400.
1272 	 * From the different datasheets, it is not even clear if this mode
1273 	 * is officially supported by any of the SoCs
1274 	 */
1275 	mmc->caps2 &= ~MMC_CAP2_HS400;
1276 
1277 	if (host->dram_access_quirk) {
1278 		/*
1279 		 * The MMC Controller embeds 1,5KiB of internal SRAM
1280 		 * that can be used to be used as bounce buffer.
1281 		 * In the case of the G12A SDIO controller, use these
1282 		 * instead of the DDR memory
1283 		 */
1284 		host->bounce_buf_size = SD_EMMC_SRAM_DATA_BUF_LEN;
1285 		host->bounce_iomem_buf = host->regs + SD_EMMC_SRAM_DATA_BUF_OFF;
1286 		host->bounce_dma_addr = res->start + SD_EMMC_SRAM_DATA_BUF_OFF;
1287 	} else {
1288 		/* data bounce buffer */
1289 		host->bounce_buf_size = mmc->max_req_size;
1290 		host->bounce_buf =
1291 			dmam_alloc_coherent(host->dev, host->bounce_buf_size,
1292 					    &host->bounce_dma_addr, GFP_KERNEL);
1293 		if (host->bounce_buf == NULL) {
1294 			dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n");
1295 			ret = -ENOMEM;
1296 			goto err_free_irq;
1297 		}
1298 	}
1299 
1300 	host->descs = dmam_alloc_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
1301 					  &host->descs_dma_addr, GFP_KERNEL);
1302 	if (!host->descs) {
1303 		dev_err(host->dev, "Allocating descriptor DMA buffer failed\n");
1304 		ret = -ENOMEM;
1305 		goto err_free_irq;
1306 	}
1307 
1308 	mmc->ops = &meson_mmc_ops;
1309 	ret = mmc_add_host(mmc);
1310 	if (ret)
1311 		goto err_free_irq;
1312 
1313 	return 0;
1314 
1315 err_free_irq:
1316 	free_irq(host->irq, host);
1317 err_init_clk:
1318 	clk_disable_unprepare(host->mmc_clk);
1319 	return ret;
1320 }
1321 
1322 static int meson_mmc_remove(struct platform_device *pdev)
1323 {
1324 	struct meson_host *host = dev_get_drvdata(&pdev->dev);
1325 
1326 	mmc_remove_host(host->mmc);
1327 
1328 	/* disable interrupts */
1329 	writel(0, host->regs + SD_EMMC_IRQ_EN);
1330 	free_irq(host->irq, host);
1331 
1332 	clk_disable_unprepare(host->mmc_clk);
1333 
1334 	return 0;
1335 }
1336 
1337 static const struct meson_mmc_data meson_gx_data = {
1338 	.tx_delay_mask	= CLK_V2_TX_DELAY_MASK,
1339 	.rx_delay_mask	= CLK_V2_RX_DELAY_MASK,
1340 	.always_on	= CLK_V2_ALWAYS_ON,
1341 	.adjust		= SD_EMMC_ADJUST,
1342 	.irq_sdio_sleep	= CLK_V2_IRQ_SDIO_SLEEP,
1343 };
1344 
1345 static const struct meson_mmc_data meson_axg_data = {
1346 	.tx_delay_mask	= CLK_V3_TX_DELAY_MASK,
1347 	.rx_delay_mask	= CLK_V3_RX_DELAY_MASK,
1348 	.always_on	= CLK_V3_ALWAYS_ON,
1349 	.adjust		= SD_EMMC_V3_ADJUST,
1350 	.irq_sdio_sleep	= CLK_V3_IRQ_SDIO_SLEEP,
1351 };
1352 
1353 static const struct of_device_id meson_mmc_of_match[] = {
1354 	{ .compatible = "amlogic,meson-gx-mmc",		.data = &meson_gx_data },
1355 	{ .compatible = "amlogic,meson-gxbb-mmc", 	.data = &meson_gx_data },
1356 	{ .compatible = "amlogic,meson-gxl-mmc",	.data = &meson_gx_data },
1357 	{ .compatible = "amlogic,meson-gxm-mmc",	.data = &meson_gx_data },
1358 	{ .compatible = "amlogic,meson-axg-mmc",	.data = &meson_axg_data },
1359 	{}
1360 };
1361 MODULE_DEVICE_TABLE(of, meson_mmc_of_match);
1362 
1363 static struct platform_driver meson_mmc_driver = {
1364 	.probe		= meson_mmc_probe,
1365 	.remove		= meson_mmc_remove,
1366 	.driver		= {
1367 		.name = DRIVER_NAME,
1368 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1369 		.of_match_table = meson_mmc_of_match,
1370 	},
1371 };
1372 
1373 module_platform_driver(meson_mmc_driver);
1374 
1375 MODULE_DESCRIPTION("Amlogic S905*/GX*/AXG SD/eMMC driver");
1376 MODULE_AUTHOR("Kevin Hilman <khilman@baylibre.com>");
1377 MODULE_LICENSE("GPL v2");
1378