xref: /openbmc/linux/drivers/mmc/host/meson-gx-mmc.c (revision 35267cea)
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 
45 #define   CLK_V3_TX_DELAY_MASK GENMASK(21, 16)
46 #define   CLK_V3_RX_DELAY_MASK GENMASK(27, 22)
47 #define   CLK_V3_ALWAYS_ON BIT(28)
48 
49 #define   CLK_TX_DELAY_MASK(h)		(h->data->tx_delay_mask)
50 #define   CLK_RX_DELAY_MASK(h)		(h->data->rx_delay_mask)
51 #define   CLK_ALWAYS_ON(h)		(h->data->always_on)
52 
53 #define SD_EMMC_DELAY 0x4
54 #define SD_EMMC_ADJUST 0x8
55 #define   ADJUST_ADJ_DELAY_MASK GENMASK(21, 16)
56 #define   ADJUST_DS_EN BIT(15)
57 #define   ADJUST_ADJ_EN BIT(13)
58 
59 #define SD_EMMC_DELAY1 0x4
60 #define SD_EMMC_DELAY2 0x8
61 #define SD_EMMC_V3_ADJUST 0xc
62 
63 #define SD_EMMC_CALOUT 0x10
64 #define SD_EMMC_START 0x40
65 #define   START_DESC_INIT BIT(0)
66 #define   START_DESC_BUSY BIT(1)
67 #define   START_DESC_ADDR_MASK GENMASK(31, 2)
68 
69 #define SD_EMMC_CFG 0x44
70 #define   CFG_BUS_WIDTH_MASK GENMASK(1, 0)
71 #define   CFG_BUS_WIDTH_1 0x0
72 #define   CFG_BUS_WIDTH_4 0x1
73 #define   CFG_BUS_WIDTH_8 0x2
74 #define   CFG_DDR BIT(2)
75 #define   CFG_BLK_LEN_MASK GENMASK(7, 4)
76 #define   CFG_RESP_TIMEOUT_MASK GENMASK(11, 8)
77 #define   CFG_RC_CC_MASK GENMASK(15, 12)
78 #define   CFG_STOP_CLOCK BIT(22)
79 #define   CFG_CLK_ALWAYS_ON BIT(18)
80 #define   CFG_CHK_DS BIT(20)
81 #define   CFG_AUTO_CLK BIT(23)
82 #define   CFG_ERR_ABORT BIT(27)
83 
84 #define SD_EMMC_STATUS 0x48
85 #define   STATUS_BUSY BIT(31)
86 #define   STATUS_DESC_BUSY BIT(30)
87 #define   STATUS_DATI GENMASK(23, 16)
88 
89 #define SD_EMMC_IRQ_EN 0x4c
90 #define   IRQ_RXD_ERR_MASK GENMASK(7, 0)
91 #define   IRQ_TXD_ERR BIT(8)
92 #define   IRQ_DESC_ERR BIT(9)
93 #define   IRQ_RESP_ERR BIT(10)
94 #define   IRQ_CRC_ERR \
95 	(IRQ_RXD_ERR_MASK | IRQ_TXD_ERR | IRQ_DESC_ERR | IRQ_RESP_ERR)
96 #define   IRQ_RESP_TIMEOUT BIT(11)
97 #define   IRQ_DESC_TIMEOUT BIT(12)
98 #define   IRQ_TIMEOUTS \
99 	(IRQ_RESP_TIMEOUT | IRQ_DESC_TIMEOUT)
100 #define   IRQ_END_OF_CHAIN BIT(13)
101 #define   IRQ_RESP_STATUS BIT(14)
102 #define   IRQ_SDIO BIT(15)
103 #define   IRQ_EN_MASK \
104 	(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN | IRQ_RESP_STATUS |\
105 	 IRQ_SDIO)
106 
107 #define SD_EMMC_CMD_CFG 0x50
108 #define SD_EMMC_CMD_ARG 0x54
109 #define SD_EMMC_CMD_DAT 0x58
110 #define SD_EMMC_CMD_RSP 0x5c
111 #define SD_EMMC_CMD_RSP1 0x60
112 #define SD_EMMC_CMD_RSP2 0x64
113 #define SD_EMMC_CMD_RSP3 0x68
114 
115 #define SD_EMMC_RXD 0x94
116 #define SD_EMMC_TXD 0x94
117 #define SD_EMMC_LAST_REG SD_EMMC_TXD
118 
119 #define SD_EMMC_SRAM_DATA_BUF_LEN 1536
120 #define SD_EMMC_SRAM_DATA_BUF_OFF 0x200
121 
122 #define SD_EMMC_CFG_BLK_SIZE 512 /* internal buffer max: 512 bytes */
123 #define SD_EMMC_CFG_RESP_TIMEOUT 256 /* in clock cycles */
124 #define SD_EMMC_CMD_TIMEOUT 1024 /* in ms */
125 #define SD_EMMC_CMD_TIMEOUT_DATA 4096 /* in ms */
126 #define SD_EMMC_CFG_CMD_GAP 16 /* in clock cycles */
127 #define SD_EMMC_DESC_BUF_LEN PAGE_SIZE
128 
129 #define SD_EMMC_PRE_REQ_DONE BIT(0)
130 #define SD_EMMC_DESC_CHAIN_MODE BIT(1)
131 
132 #define MUX_CLK_NUM_PARENTS 2
133 
134 struct meson_mmc_data {
135 	unsigned int tx_delay_mask;
136 	unsigned int rx_delay_mask;
137 	unsigned int always_on;
138 	unsigned int adjust;
139 };
140 
141 struct sd_emmc_desc {
142 	u32 cmd_cfg;
143 	u32 cmd_arg;
144 	u32 cmd_data;
145 	u32 cmd_resp;
146 };
147 
148 struct meson_host {
149 	struct	device		*dev;
150 	struct	meson_mmc_data *data;
151 	struct	mmc_host	*mmc;
152 	struct	mmc_command	*cmd;
153 
154 	void __iomem *regs;
155 	struct clk *core_clk;
156 	struct clk *mux_clk;
157 	struct clk *mmc_clk;
158 	unsigned long req_rate;
159 	bool ddr;
160 
161 	bool dram_access_quirk;
162 
163 	struct pinctrl *pinctrl;
164 	struct pinctrl_state *pins_clk_gate;
165 
166 	unsigned int bounce_buf_size;
167 	void *bounce_buf;
168 	void __iomem *bounce_iomem_buf;
169 	dma_addr_t bounce_dma_addr;
170 	struct sd_emmc_desc *descs;
171 	dma_addr_t descs_dma_addr;
172 
173 	int irq;
174 
175 	bool vqmmc_enabled;
176 };
177 
178 #define CMD_CFG_LENGTH_MASK GENMASK(8, 0)
179 #define CMD_CFG_BLOCK_MODE BIT(9)
180 #define CMD_CFG_R1B BIT(10)
181 #define CMD_CFG_END_OF_CHAIN BIT(11)
182 #define CMD_CFG_TIMEOUT_MASK GENMASK(15, 12)
183 #define CMD_CFG_NO_RESP BIT(16)
184 #define CMD_CFG_NO_CMD BIT(17)
185 #define CMD_CFG_DATA_IO BIT(18)
186 #define CMD_CFG_DATA_WR BIT(19)
187 #define CMD_CFG_RESP_NOCRC BIT(20)
188 #define CMD_CFG_RESP_128 BIT(21)
189 #define CMD_CFG_RESP_NUM BIT(22)
190 #define CMD_CFG_DATA_NUM BIT(23)
191 #define CMD_CFG_CMD_INDEX_MASK GENMASK(29, 24)
192 #define CMD_CFG_ERROR BIT(30)
193 #define CMD_CFG_OWNER BIT(31)
194 
195 #define CMD_DATA_MASK GENMASK(31, 2)
196 #define CMD_DATA_BIG_ENDIAN BIT(1)
197 #define CMD_DATA_SRAM BIT(0)
198 #define CMD_RESP_MASK GENMASK(31, 1)
199 #define CMD_RESP_SRAM BIT(0)
200 
201 static unsigned int meson_mmc_get_timeout_msecs(struct mmc_data *data)
202 {
203 	unsigned int timeout = data->timeout_ns / NSEC_PER_MSEC;
204 
205 	if (!timeout)
206 		return SD_EMMC_CMD_TIMEOUT_DATA;
207 
208 	timeout = roundup_pow_of_two(timeout);
209 
210 	return min(timeout, 32768U); /* max. 2^15 ms */
211 }
212 
213 static struct mmc_command *meson_mmc_get_next_command(struct mmc_command *cmd)
214 {
215 	if (cmd->opcode == MMC_SET_BLOCK_COUNT && !cmd->error)
216 		return cmd->mrq->cmd;
217 	else if (mmc_op_multi(cmd->opcode) &&
218 		 (!cmd->mrq->sbc || cmd->error || cmd->data->error))
219 		return cmd->mrq->stop;
220 	else
221 		return NULL;
222 }
223 
224 static void meson_mmc_get_transfer_mode(struct mmc_host *mmc,
225 					struct mmc_request *mrq)
226 {
227 	struct meson_host *host = mmc_priv(mmc);
228 	struct mmc_data *data = mrq->data;
229 	struct scatterlist *sg;
230 	int i;
231 
232 	/*
233 	 * When Controller DMA cannot directly access DDR memory, disable
234 	 * support for Chain Mode to directly use the internal SRAM using
235 	 * the bounce buffer mode.
236 	 */
237 	if (host->dram_access_quirk)
238 		return;
239 
240 	/* SD_IO_RW_EXTENDED (CMD53) can also use block mode under the hood */
241 	if (data->blocks > 1 || mrq->cmd->opcode == SD_IO_RW_EXTENDED) {
242 		/*
243 		 * In block mode DMA descriptor format, "length" field indicates
244 		 * number of blocks and there is no way to pass DMA size that
245 		 * is not multiple of SDIO block size, making it impossible to
246 		 * tie more than one memory buffer with single SDIO block.
247 		 * Block mode sg buffer size should be aligned with SDIO block
248 		 * size, otherwise chain mode could not be used.
249 		 */
250 		for_each_sg(data->sg, sg, data->sg_len, i) {
251 			if (sg->length % data->blksz) {
252 				dev_warn_once(mmc_dev(mmc),
253 					      "unaligned sg len %u blksize %u, disabling descriptor DMA for transfer\n",
254 					      sg->length, data->blksz);
255 				return;
256 			}
257 		}
258 	}
259 
260 	for_each_sg(data->sg, sg, data->sg_len, i) {
261 		/* check for 8 byte alignment */
262 		if (sg->offset % 8) {
263 			dev_warn_once(mmc_dev(mmc),
264 				      "unaligned sg offset %u, disabling descriptor DMA for transfer\n",
265 				      sg->offset);
266 			return;
267 		}
268 	}
269 
270 	data->host_cookie |= SD_EMMC_DESC_CHAIN_MODE;
271 }
272 
273 static inline bool meson_mmc_desc_chain_mode(const struct mmc_data *data)
274 {
275 	return data->host_cookie & SD_EMMC_DESC_CHAIN_MODE;
276 }
277 
278 static inline bool meson_mmc_bounce_buf_read(const struct mmc_data *data)
279 {
280 	return data && data->flags & MMC_DATA_READ &&
281 	       !meson_mmc_desc_chain_mode(data);
282 }
283 
284 static void meson_mmc_pre_req(struct mmc_host *mmc, struct mmc_request *mrq)
285 {
286 	struct mmc_data *data = mrq->data;
287 
288 	if (!data)
289 		return;
290 
291 	meson_mmc_get_transfer_mode(mmc, mrq);
292 	data->host_cookie |= SD_EMMC_PRE_REQ_DONE;
293 
294 	if (!meson_mmc_desc_chain_mode(data))
295 		return;
296 
297 	data->sg_count = dma_map_sg(mmc_dev(mmc), data->sg, data->sg_len,
298                                    mmc_get_dma_dir(data));
299 	if (!data->sg_count)
300 		dev_err(mmc_dev(mmc), "dma_map_sg failed");
301 }
302 
303 static void meson_mmc_post_req(struct mmc_host *mmc, struct mmc_request *mrq,
304 			       int err)
305 {
306 	struct mmc_data *data = mrq->data;
307 
308 	if (data && meson_mmc_desc_chain_mode(data) && data->sg_count)
309 		dma_unmap_sg(mmc_dev(mmc), data->sg, data->sg_len,
310 			     mmc_get_dma_dir(data));
311 }
312 
313 /*
314  * Gating the clock on this controller is tricky.  It seems the mmc clock
315  * is also used by the controller.  It may crash during some operation if the
316  * clock is stopped.  The safest thing to do, whenever possible, is to keep
317  * clock running at stop it at the pad using the pinmux.
318  */
319 static void meson_mmc_clk_gate(struct meson_host *host)
320 {
321 	u32 cfg;
322 
323 	if (host->pins_clk_gate) {
324 		pinctrl_select_state(host->pinctrl, host->pins_clk_gate);
325 	} else {
326 		/*
327 		 * If the pinmux is not provided - default to the classic and
328 		 * unsafe method
329 		 */
330 		cfg = readl(host->regs + SD_EMMC_CFG);
331 		cfg |= CFG_STOP_CLOCK;
332 		writel(cfg, host->regs + SD_EMMC_CFG);
333 	}
334 }
335 
336 static void meson_mmc_clk_ungate(struct meson_host *host)
337 {
338 	u32 cfg;
339 
340 	if (host->pins_clk_gate)
341 		pinctrl_select_default_state(host->dev);
342 
343 	/* Make sure the clock is not stopped in the controller */
344 	cfg = readl(host->regs + SD_EMMC_CFG);
345 	cfg &= ~CFG_STOP_CLOCK;
346 	writel(cfg, host->regs + SD_EMMC_CFG);
347 }
348 
349 static int meson_mmc_clk_set(struct meson_host *host, unsigned long rate,
350 			     bool ddr)
351 {
352 	struct mmc_host *mmc = host->mmc;
353 	int ret;
354 	u32 cfg;
355 
356 	/* Same request - bail-out */
357 	if (host->ddr == ddr && host->req_rate == rate)
358 		return 0;
359 
360 	/* stop clock */
361 	meson_mmc_clk_gate(host);
362 	host->req_rate = 0;
363 	mmc->actual_clock = 0;
364 
365 	/* return with clock being stopped */
366 	if (!rate)
367 		return 0;
368 
369 	/* Stop the clock during rate change to avoid glitches */
370 	cfg = readl(host->regs + SD_EMMC_CFG);
371 	cfg |= CFG_STOP_CLOCK;
372 	writel(cfg, host->regs + SD_EMMC_CFG);
373 
374 	if (ddr) {
375 		/* DDR modes require higher module clock */
376 		rate <<= 1;
377 		cfg |= CFG_DDR;
378 	} else {
379 		cfg &= ~CFG_DDR;
380 	}
381 	writel(cfg, host->regs + SD_EMMC_CFG);
382 	host->ddr = ddr;
383 
384 	ret = clk_set_rate(host->mmc_clk, rate);
385 	if (ret) {
386 		dev_err(host->dev, "Unable to set cfg_div_clk to %lu. ret=%d\n",
387 			rate, ret);
388 		return ret;
389 	}
390 
391 	host->req_rate = rate;
392 	mmc->actual_clock = clk_get_rate(host->mmc_clk);
393 
394 	/* We should report the real output frequency of the controller */
395 	if (ddr) {
396 		host->req_rate >>= 1;
397 		mmc->actual_clock >>= 1;
398 	}
399 
400 	dev_dbg(host->dev, "clk rate: %u Hz\n", mmc->actual_clock);
401 	if (rate != mmc->actual_clock)
402 		dev_dbg(host->dev, "requested rate was %lu\n", rate);
403 
404 	/* (re)start clock */
405 	meson_mmc_clk_ungate(host);
406 
407 	return 0;
408 }
409 
410 /*
411  * The SD/eMMC IP block has an internal mux and divider used for
412  * generating the MMC clock.  Use the clock framework to create and
413  * manage these clocks.
414  */
415 static int meson_mmc_clk_init(struct meson_host *host)
416 {
417 	struct clk_init_data init;
418 	struct clk_mux *mux;
419 	struct clk_divider *div;
420 	char clk_name[32];
421 	int i, ret = 0;
422 	const char *mux_parent_names[MUX_CLK_NUM_PARENTS];
423 	const char *clk_parent[1];
424 	u32 clk_reg;
425 
426 	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
427 	clk_reg = CLK_ALWAYS_ON(host);
428 	clk_reg |= CLK_DIV_MASK;
429 	clk_reg |= FIELD_PREP(CLK_CORE_PHASE_MASK, CLK_PHASE_180);
430 	clk_reg |= FIELD_PREP(CLK_TX_PHASE_MASK, CLK_PHASE_0);
431 	clk_reg |= FIELD_PREP(CLK_RX_PHASE_MASK, CLK_PHASE_0);
432 	writel(clk_reg, host->regs + SD_EMMC_CLOCK);
433 
434 	/* get the mux parents */
435 	for (i = 0; i < MUX_CLK_NUM_PARENTS; i++) {
436 		struct clk *clk;
437 		char name[16];
438 
439 		snprintf(name, sizeof(name), "clkin%d", i);
440 		clk = devm_clk_get(host->dev, name);
441 		if (IS_ERR(clk))
442 			return dev_err_probe(host->dev, PTR_ERR(clk),
443 					     "Missing clock %s\n", name);
444 
445 		mux_parent_names[i] = __clk_get_name(clk);
446 	}
447 
448 	/* create the mux */
449 	mux = devm_kzalloc(host->dev, sizeof(*mux), GFP_KERNEL);
450 	if (!mux)
451 		return -ENOMEM;
452 
453 	snprintf(clk_name, sizeof(clk_name), "%s#mux", dev_name(host->dev));
454 	init.name = clk_name;
455 	init.ops = &clk_mux_ops;
456 	init.flags = 0;
457 	init.parent_names = mux_parent_names;
458 	init.num_parents = MUX_CLK_NUM_PARENTS;
459 
460 	mux->reg = host->regs + SD_EMMC_CLOCK;
461 	mux->shift = __ffs(CLK_SRC_MASK);
462 	mux->mask = CLK_SRC_MASK >> mux->shift;
463 	mux->hw.init = &init;
464 
465 	host->mux_clk = devm_clk_register(host->dev, &mux->hw);
466 	if (WARN_ON(IS_ERR(host->mux_clk)))
467 		return PTR_ERR(host->mux_clk);
468 
469 	/* create the divider */
470 	div = devm_kzalloc(host->dev, sizeof(*div), GFP_KERNEL);
471 	if (!div)
472 		return -ENOMEM;
473 
474 	snprintf(clk_name, sizeof(clk_name), "%s#div", dev_name(host->dev));
475 	init.name = clk_name;
476 	init.ops = &clk_divider_ops;
477 	init.flags = CLK_SET_RATE_PARENT;
478 	clk_parent[0] = __clk_get_name(host->mux_clk);
479 	init.parent_names = clk_parent;
480 	init.num_parents = 1;
481 
482 	div->reg = host->regs + SD_EMMC_CLOCK;
483 	div->shift = __ffs(CLK_DIV_MASK);
484 	div->width = __builtin_popcountl(CLK_DIV_MASK);
485 	div->hw.init = &init;
486 	div->flags = CLK_DIVIDER_ONE_BASED;
487 
488 	host->mmc_clk = devm_clk_register(host->dev, &div->hw);
489 	if (WARN_ON(IS_ERR(host->mmc_clk)))
490 		return PTR_ERR(host->mmc_clk);
491 
492 	/* init SD_EMMC_CLOCK to sane defaults w/min clock rate */
493 	host->mmc->f_min = clk_round_rate(host->mmc_clk, 400000);
494 	ret = clk_set_rate(host->mmc_clk, host->mmc->f_min);
495 	if (ret)
496 		return ret;
497 
498 	return clk_prepare_enable(host->mmc_clk);
499 }
500 
501 static void meson_mmc_disable_resampling(struct meson_host *host)
502 {
503 	unsigned int val = readl(host->regs + host->data->adjust);
504 
505 	val &= ~ADJUST_ADJ_EN;
506 	writel(val, host->regs + host->data->adjust);
507 }
508 
509 static void meson_mmc_reset_resampling(struct meson_host *host)
510 {
511 	unsigned int val;
512 
513 	meson_mmc_disable_resampling(host);
514 
515 	val = readl(host->regs + host->data->adjust);
516 	val &= ~ADJUST_ADJ_DELAY_MASK;
517 	writel(val, host->regs + host->data->adjust);
518 }
519 
520 static int meson_mmc_resampling_tuning(struct mmc_host *mmc, u32 opcode)
521 {
522 	struct meson_host *host = mmc_priv(mmc);
523 	unsigned int val, dly, max_dly, i;
524 	int ret;
525 
526 	/* Resampling is done using the source clock */
527 	max_dly = DIV_ROUND_UP(clk_get_rate(host->mux_clk),
528 			       clk_get_rate(host->mmc_clk));
529 
530 	val = readl(host->regs + host->data->adjust);
531 	val |= ADJUST_ADJ_EN;
532 	writel(val, host->regs + host->data->adjust);
533 
534 	if (mmc_doing_retune(mmc))
535 		dly = FIELD_GET(ADJUST_ADJ_DELAY_MASK, val) + 1;
536 	else
537 		dly = 0;
538 
539 	for (i = 0; i < max_dly; i++) {
540 		val &= ~ADJUST_ADJ_DELAY_MASK;
541 		val |= FIELD_PREP(ADJUST_ADJ_DELAY_MASK, (dly + i) % max_dly);
542 		writel(val, host->regs + host->data->adjust);
543 
544 		ret = mmc_send_tuning(mmc, opcode, NULL);
545 		if (!ret) {
546 			dev_dbg(mmc_dev(mmc), "resampling delay: %u\n",
547 				(dly + i) % max_dly);
548 			return 0;
549 		}
550 	}
551 
552 	meson_mmc_reset_resampling(host);
553 	return -EIO;
554 }
555 
556 static int meson_mmc_prepare_ios_clock(struct meson_host *host,
557 				       struct mmc_ios *ios)
558 {
559 	bool ddr;
560 
561 	switch (ios->timing) {
562 	case MMC_TIMING_MMC_DDR52:
563 	case MMC_TIMING_UHS_DDR50:
564 		ddr = true;
565 		break;
566 
567 	default:
568 		ddr = false;
569 		break;
570 	}
571 
572 	return meson_mmc_clk_set(host, ios->clock, ddr);
573 }
574 
575 static void meson_mmc_check_resampling(struct meson_host *host,
576 				       struct mmc_ios *ios)
577 {
578 	switch (ios->timing) {
579 	case MMC_TIMING_LEGACY:
580 	case MMC_TIMING_MMC_HS:
581 	case MMC_TIMING_SD_HS:
582 	case MMC_TIMING_MMC_DDR52:
583 		meson_mmc_disable_resampling(host);
584 		break;
585 	}
586 }
587 
588 static void meson_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
589 {
590 	struct meson_host *host = mmc_priv(mmc);
591 	u32 bus_width, val;
592 	int err;
593 
594 	/*
595 	 * GPIO regulator, only controls switching between 1v8 and
596 	 * 3v3, doesn't support MMC_POWER_OFF, MMC_POWER_ON.
597 	 */
598 	switch (ios->power_mode) {
599 	case MMC_POWER_OFF:
600 		if (!IS_ERR(mmc->supply.vmmc))
601 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, 0);
602 
603 		if (!IS_ERR(mmc->supply.vqmmc) && host->vqmmc_enabled) {
604 			regulator_disable(mmc->supply.vqmmc);
605 			host->vqmmc_enabled = false;
606 		}
607 
608 		break;
609 
610 	case MMC_POWER_UP:
611 		if (!IS_ERR(mmc->supply.vmmc))
612 			mmc_regulator_set_ocr(mmc, mmc->supply.vmmc, ios->vdd);
613 
614 		break;
615 
616 	case MMC_POWER_ON:
617 		if (!IS_ERR(mmc->supply.vqmmc) && !host->vqmmc_enabled) {
618 			int ret = regulator_enable(mmc->supply.vqmmc);
619 
620 			if (ret < 0)
621 				dev_err(host->dev,
622 					"failed to enable vqmmc regulator\n");
623 			else
624 				host->vqmmc_enabled = true;
625 		}
626 
627 		break;
628 	}
629 
630 	/* Bus width */
631 	switch (ios->bus_width) {
632 	case MMC_BUS_WIDTH_1:
633 		bus_width = CFG_BUS_WIDTH_1;
634 		break;
635 	case MMC_BUS_WIDTH_4:
636 		bus_width = CFG_BUS_WIDTH_4;
637 		break;
638 	case MMC_BUS_WIDTH_8:
639 		bus_width = CFG_BUS_WIDTH_8;
640 		break;
641 	default:
642 		dev_err(host->dev, "Invalid ios->bus_width: %u.  Setting to 4.\n",
643 			ios->bus_width);
644 		bus_width = CFG_BUS_WIDTH_4;
645 	}
646 
647 	val = readl(host->regs + SD_EMMC_CFG);
648 	val &= ~CFG_BUS_WIDTH_MASK;
649 	val |= FIELD_PREP(CFG_BUS_WIDTH_MASK, bus_width);
650 	writel(val, host->regs + SD_EMMC_CFG);
651 
652 	meson_mmc_check_resampling(host, ios);
653 	err = meson_mmc_prepare_ios_clock(host, ios);
654 	if (err)
655 		dev_err(host->dev, "Failed to set clock: %d\n,", err);
656 
657 	dev_dbg(host->dev, "SD_EMMC_CFG:  0x%08x\n", val);
658 }
659 
660 static void meson_mmc_request_done(struct mmc_host *mmc,
661 				   struct mmc_request *mrq)
662 {
663 	struct meson_host *host = mmc_priv(mmc);
664 
665 	host->cmd = NULL;
666 	mmc_request_done(host->mmc, mrq);
667 }
668 
669 static void meson_mmc_set_blksz(struct mmc_host *mmc, unsigned int blksz)
670 {
671 	struct meson_host *host = mmc_priv(mmc);
672 	u32 cfg, blksz_old;
673 
674 	cfg = readl(host->regs + SD_EMMC_CFG);
675 	blksz_old = FIELD_GET(CFG_BLK_LEN_MASK, cfg);
676 
677 	if (!is_power_of_2(blksz))
678 		dev_err(host->dev, "blksz %u is not a power of 2\n", blksz);
679 
680 	blksz = ilog2(blksz);
681 
682 	/* check if block-size matches, if not update */
683 	if (blksz == blksz_old)
684 		return;
685 
686 	dev_dbg(host->dev, "%s: update blk_len %d -> %d\n", __func__,
687 		blksz_old, blksz);
688 
689 	cfg &= ~CFG_BLK_LEN_MASK;
690 	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, blksz);
691 	writel(cfg, host->regs + SD_EMMC_CFG);
692 }
693 
694 static void meson_mmc_set_response_bits(struct mmc_command *cmd, u32 *cmd_cfg)
695 {
696 	if (cmd->flags & MMC_RSP_PRESENT) {
697 		if (cmd->flags & MMC_RSP_136)
698 			*cmd_cfg |= CMD_CFG_RESP_128;
699 		*cmd_cfg |= CMD_CFG_RESP_NUM;
700 
701 		if (!(cmd->flags & MMC_RSP_CRC))
702 			*cmd_cfg |= CMD_CFG_RESP_NOCRC;
703 
704 		if (cmd->flags & MMC_RSP_BUSY)
705 			*cmd_cfg |= CMD_CFG_R1B;
706 	} else {
707 		*cmd_cfg |= CMD_CFG_NO_RESP;
708 	}
709 }
710 
711 static void meson_mmc_desc_chain_transfer(struct mmc_host *mmc, u32 cmd_cfg)
712 {
713 	struct meson_host *host = mmc_priv(mmc);
714 	struct sd_emmc_desc *desc = host->descs;
715 	struct mmc_data *data = host->cmd->data;
716 	struct scatterlist *sg;
717 	u32 start;
718 	int i;
719 
720 	if (data->flags & MMC_DATA_WRITE)
721 		cmd_cfg |= CMD_CFG_DATA_WR;
722 
723 	if (data->blocks > 1) {
724 		cmd_cfg |= CMD_CFG_BLOCK_MODE;
725 		meson_mmc_set_blksz(mmc, data->blksz);
726 	}
727 
728 	for_each_sg(data->sg, sg, data->sg_count, i) {
729 		unsigned int len = sg_dma_len(sg);
730 
731 		if (data->blocks > 1)
732 			len /= data->blksz;
733 
734 		desc[i].cmd_cfg = cmd_cfg;
735 		desc[i].cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, len);
736 		if (i > 0)
737 			desc[i].cmd_cfg |= CMD_CFG_NO_CMD;
738 		desc[i].cmd_arg = host->cmd->arg;
739 		desc[i].cmd_resp = 0;
740 		desc[i].cmd_data = sg_dma_address(sg);
741 	}
742 	desc[data->sg_count - 1].cmd_cfg |= CMD_CFG_END_OF_CHAIN;
743 
744 	dma_wmb(); /* ensure descriptor is written before kicked */
745 	start = host->descs_dma_addr | START_DESC_BUSY;
746 	writel(start, host->regs + SD_EMMC_START);
747 }
748 
749 /* local sg copy to buffer version with _to/fromio usage for dram_access_quirk */
750 static void meson_mmc_copy_buffer(struct meson_host *host, struct mmc_data *data,
751 				  size_t buflen, bool to_buffer)
752 {
753 	unsigned int sg_flags = SG_MITER_ATOMIC;
754 	struct scatterlist *sgl = data->sg;
755 	unsigned int nents = data->sg_len;
756 	struct sg_mapping_iter miter;
757 	unsigned int offset = 0;
758 
759 	if (to_buffer)
760 		sg_flags |= SG_MITER_FROM_SG;
761 	else
762 		sg_flags |= SG_MITER_TO_SG;
763 
764 	sg_miter_start(&miter, sgl, nents, sg_flags);
765 
766 	while ((offset < buflen) && sg_miter_next(&miter)) {
767 		unsigned int len;
768 
769 		len = min(miter.length, buflen - offset);
770 
771 		/* When dram_access_quirk, the bounce buffer is a iomem mapping */
772 		if (host->dram_access_quirk) {
773 			if (to_buffer)
774 				memcpy_toio(host->bounce_iomem_buf + offset, miter.addr, len);
775 			else
776 				memcpy_fromio(miter.addr, host->bounce_iomem_buf + offset, len);
777 		} else {
778 			if (to_buffer)
779 				memcpy(host->bounce_buf + offset, miter.addr, len);
780 			else
781 				memcpy(miter.addr, host->bounce_buf + offset, len);
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 	cmd_cfg |= CMD_CFG_ERROR; /* stop in case of error */
805 
806 	meson_mmc_set_response_bits(cmd, &cmd_cfg);
807 
808 	/* data? */
809 	if (data) {
810 		data->bytes_xfered = 0;
811 		cmd_cfg |= CMD_CFG_DATA_IO;
812 		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
813 				      ilog2(meson_mmc_get_timeout_msecs(data)));
814 
815 		if (meson_mmc_desc_chain_mode(data)) {
816 			meson_mmc_desc_chain_transfer(mmc, cmd_cfg);
817 			return;
818 		}
819 
820 		if (data->blocks > 1) {
821 			cmd_cfg |= CMD_CFG_BLOCK_MODE;
822 			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK,
823 					      data->blocks);
824 			meson_mmc_set_blksz(mmc, data->blksz);
825 		} else {
826 			cmd_cfg |= FIELD_PREP(CMD_CFG_LENGTH_MASK, data->blksz);
827 		}
828 
829 		xfer_bytes = data->blksz * data->blocks;
830 		if (data->flags & MMC_DATA_WRITE) {
831 			cmd_cfg |= CMD_CFG_DATA_WR;
832 			WARN_ON(xfer_bytes > host->bounce_buf_size);
833 			meson_mmc_copy_buffer(host, data, xfer_bytes, true);
834 			dma_wmb();
835 		}
836 
837 		cmd_data = host->bounce_dma_addr & CMD_DATA_MASK;
838 	} else {
839 		cmd_cfg |= FIELD_PREP(CMD_CFG_TIMEOUT_MASK,
840 				      ilog2(SD_EMMC_CMD_TIMEOUT));
841 	}
842 
843 	/* Last descriptor */
844 	cmd_cfg |= CMD_CFG_END_OF_CHAIN;
845 	writel(cmd_cfg, host->regs + SD_EMMC_CMD_CFG);
846 	writel(cmd_data, host->regs + SD_EMMC_CMD_DAT);
847 	writel(0, host->regs + SD_EMMC_CMD_RSP);
848 	wmb(); /* ensure descriptor is written before kicked */
849 	writel(cmd->arg, host->regs + SD_EMMC_CMD_ARG);
850 }
851 
852 static void meson_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
853 {
854 	struct meson_host *host = mmc_priv(mmc);
855 	bool needs_pre_post_req = mrq->data &&
856 			!(mrq->data->host_cookie & SD_EMMC_PRE_REQ_DONE);
857 
858 	if (needs_pre_post_req) {
859 		meson_mmc_get_transfer_mode(mmc, mrq);
860 		if (!meson_mmc_desc_chain_mode(mrq->data))
861 			needs_pre_post_req = false;
862 	}
863 
864 	if (needs_pre_post_req)
865 		meson_mmc_pre_req(mmc, mrq);
866 
867 	/* Stop execution */
868 	writel(0, host->regs + SD_EMMC_START);
869 
870 	meson_mmc_start_cmd(mmc, mrq->sbc ?: mrq->cmd);
871 
872 	if (needs_pre_post_req)
873 		meson_mmc_post_req(mmc, mrq, 0);
874 }
875 
876 static void meson_mmc_read_resp(struct mmc_host *mmc, struct mmc_command *cmd)
877 {
878 	struct meson_host *host = mmc_priv(mmc);
879 
880 	if (cmd->flags & MMC_RSP_136) {
881 		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP3);
882 		cmd->resp[1] = readl(host->regs + SD_EMMC_CMD_RSP2);
883 		cmd->resp[2] = readl(host->regs + SD_EMMC_CMD_RSP1);
884 		cmd->resp[3] = readl(host->regs + SD_EMMC_CMD_RSP);
885 	} else if (cmd->flags & MMC_RSP_PRESENT) {
886 		cmd->resp[0] = readl(host->regs + SD_EMMC_CMD_RSP);
887 	}
888 }
889 
890 static irqreturn_t meson_mmc_irq(int irq, void *dev_id)
891 {
892 	struct meson_host *host = dev_id;
893 	struct mmc_command *cmd;
894 	struct mmc_data *data;
895 	u32 irq_en, status, raw_status;
896 	irqreturn_t ret = IRQ_NONE;
897 
898 	irq_en = readl(host->regs + SD_EMMC_IRQ_EN);
899 	raw_status = readl(host->regs + SD_EMMC_STATUS);
900 	status = raw_status & irq_en;
901 
902 	if (!status) {
903 		dev_dbg(host->dev,
904 			"Unexpected IRQ! irq_en 0x%08x - status 0x%08x\n",
905 			 irq_en, raw_status);
906 		return IRQ_NONE;
907 	}
908 
909 	if (WARN_ON(!host) || WARN_ON(!host->cmd))
910 		return IRQ_NONE;
911 
912 	/* ack all raised interrupts */
913 	writel(status, host->regs + SD_EMMC_STATUS);
914 
915 	cmd = host->cmd;
916 	data = cmd->data;
917 	cmd->error = 0;
918 	if (status & IRQ_CRC_ERR) {
919 		dev_dbg(host->dev, "CRC Error - status 0x%08x\n", status);
920 		cmd->error = -EILSEQ;
921 		ret = IRQ_WAKE_THREAD;
922 		goto out;
923 	}
924 
925 	if (status & IRQ_TIMEOUTS) {
926 		dev_dbg(host->dev, "Timeout - status 0x%08x\n", status);
927 		cmd->error = -ETIMEDOUT;
928 		ret = IRQ_WAKE_THREAD;
929 		goto out;
930 	}
931 
932 	meson_mmc_read_resp(host->mmc, cmd);
933 
934 	if (status & IRQ_SDIO) {
935 		dev_dbg(host->dev, "IRQ: SDIO TODO.\n");
936 		ret = IRQ_HANDLED;
937 	}
938 
939 	if (status & (IRQ_END_OF_CHAIN | IRQ_RESP_STATUS)) {
940 		if (data && !cmd->error)
941 			data->bytes_xfered = data->blksz * data->blocks;
942 		if (meson_mmc_bounce_buf_read(data) ||
943 		    meson_mmc_get_next_command(cmd))
944 			ret = IRQ_WAKE_THREAD;
945 		else
946 			ret = IRQ_HANDLED;
947 	}
948 
949 out:
950 	if (cmd->error) {
951 		/* Stop desc in case of errors */
952 		u32 start = readl(host->regs + SD_EMMC_START);
953 
954 		start &= ~START_DESC_BUSY;
955 		writel(start, host->regs + SD_EMMC_START);
956 	}
957 
958 	if (ret == IRQ_HANDLED)
959 		meson_mmc_request_done(host->mmc, cmd->mrq);
960 
961 	return ret;
962 }
963 
964 static int meson_mmc_wait_desc_stop(struct meson_host *host)
965 {
966 	u32 status;
967 
968 	/*
969 	 * It may sometimes take a while for it to actually halt. Here, we
970 	 * are giving it 5ms to comply
971 	 *
972 	 * If we don't confirm the descriptor is stopped, it might raise new
973 	 * IRQs after we have called mmc_request_done() which is bad.
974 	 */
975 
976 	return readl_poll_timeout(host->regs + SD_EMMC_STATUS, status,
977 				  !(status & (STATUS_BUSY | STATUS_DESC_BUSY)),
978 				  100, 5000);
979 }
980 
981 static irqreturn_t meson_mmc_irq_thread(int irq, void *dev_id)
982 {
983 	struct meson_host *host = dev_id;
984 	struct mmc_command *next_cmd, *cmd = host->cmd;
985 	struct mmc_data *data;
986 	unsigned int xfer_bytes;
987 
988 	if (WARN_ON(!cmd))
989 		return IRQ_NONE;
990 
991 	if (cmd->error) {
992 		meson_mmc_wait_desc_stop(host);
993 		meson_mmc_request_done(host->mmc, cmd->mrq);
994 
995 		return IRQ_HANDLED;
996 	}
997 
998 	data = cmd->data;
999 	if (meson_mmc_bounce_buf_read(data)) {
1000 		xfer_bytes = data->blksz * data->blocks;
1001 		WARN_ON(xfer_bytes > host->bounce_buf_size);
1002 		meson_mmc_copy_buffer(host, data, xfer_bytes, false);
1003 	}
1004 
1005 	next_cmd = meson_mmc_get_next_command(cmd);
1006 	if (next_cmd)
1007 		meson_mmc_start_cmd(host->mmc, next_cmd);
1008 	else
1009 		meson_mmc_request_done(host->mmc, cmd->mrq);
1010 
1011 	return IRQ_HANDLED;
1012 }
1013 
1014 /*
1015  * NOTE: we only need this until the GPIO/pinctrl driver can handle
1016  * interrupts.  For now, the MMC core will use this for polling.
1017  */
1018 static int meson_mmc_get_cd(struct mmc_host *mmc)
1019 {
1020 	int status = mmc_gpio_get_cd(mmc);
1021 
1022 	if (status == -ENOSYS)
1023 		return 1; /* assume present */
1024 
1025 	return status;
1026 }
1027 
1028 static void meson_mmc_cfg_init(struct meson_host *host)
1029 {
1030 	u32 cfg = 0;
1031 
1032 	cfg |= FIELD_PREP(CFG_RESP_TIMEOUT_MASK,
1033 			  ilog2(SD_EMMC_CFG_RESP_TIMEOUT));
1034 	cfg |= FIELD_PREP(CFG_RC_CC_MASK, ilog2(SD_EMMC_CFG_CMD_GAP));
1035 	cfg |= FIELD_PREP(CFG_BLK_LEN_MASK, ilog2(SD_EMMC_CFG_BLK_SIZE));
1036 
1037 	/* abort chain on R/W errors */
1038 	cfg |= CFG_ERR_ABORT;
1039 
1040 	writel(cfg, host->regs + SD_EMMC_CFG);
1041 }
1042 
1043 static int meson_mmc_card_busy(struct mmc_host *mmc)
1044 {
1045 	struct meson_host *host = mmc_priv(mmc);
1046 	u32 regval;
1047 
1048 	regval = readl(host->regs + SD_EMMC_STATUS);
1049 
1050 	/* We are only interrested in lines 0 to 3, so mask the other ones */
1051 	return !(FIELD_GET(STATUS_DATI, regval) & 0xf);
1052 }
1053 
1054 static int meson_mmc_voltage_switch(struct mmc_host *mmc, struct mmc_ios *ios)
1055 {
1056 	int ret;
1057 
1058 	/* vqmmc regulator is available */
1059 	if (!IS_ERR(mmc->supply.vqmmc)) {
1060 		/*
1061 		 * The usual amlogic setup uses a GPIO to switch from one
1062 		 * regulator to the other. While the voltage ramp up is
1063 		 * pretty fast, care must be taken when switching from 3.3v
1064 		 * to 1.8v. Please make sure the regulator framework is aware
1065 		 * of your own regulator constraints
1066 		 */
1067 		ret = mmc_regulator_set_vqmmc(mmc, ios);
1068 		return ret < 0 ? ret : 0;
1069 	}
1070 
1071 	/* no vqmmc regulator, assume fixed regulator at 3/3.3V */
1072 	if (ios->signal_voltage == MMC_SIGNAL_VOLTAGE_330)
1073 		return 0;
1074 
1075 	return -EINVAL;
1076 }
1077 
1078 static const struct mmc_host_ops meson_mmc_ops = {
1079 	.request	= meson_mmc_request,
1080 	.set_ios	= meson_mmc_set_ios,
1081 	.get_cd         = meson_mmc_get_cd,
1082 	.pre_req	= meson_mmc_pre_req,
1083 	.post_req	= meson_mmc_post_req,
1084 	.execute_tuning = meson_mmc_resampling_tuning,
1085 	.card_busy	= meson_mmc_card_busy,
1086 	.start_signal_voltage_switch = meson_mmc_voltage_switch,
1087 };
1088 
1089 static int meson_mmc_probe(struct platform_device *pdev)
1090 {
1091 	struct resource *res;
1092 	struct meson_host *host;
1093 	struct mmc_host *mmc;
1094 	int ret;
1095 
1096 	mmc = mmc_alloc_host(sizeof(struct meson_host), &pdev->dev);
1097 	if (!mmc)
1098 		return -ENOMEM;
1099 	host = mmc_priv(mmc);
1100 	host->mmc = mmc;
1101 	host->dev = &pdev->dev;
1102 	dev_set_drvdata(&pdev->dev, host);
1103 
1104 	/* The G12A SDIO Controller needs an SRAM bounce buffer */
1105 	host->dram_access_quirk = device_property_read_bool(&pdev->dev,
1106 					"amlogic,dram-access-quirk");
1107 
1108 	/* Get regulators and the supported OCR mask */
1109 	host->vqmmc_enabled = false;
1110 	ret = mmc_regulator_get_supply(mmc);
1111 	if (ret)
1112 		goto free_host;
1113 
1114 	ret = mmc_of_parse(mmc);
1115 	if (ret) {
1116 		if (ret != -EPROBE_DEFER)
1117 			dev_warn(&pdev->dev, "error parsing DT: %d\n", ret);
1118 		goto free_host;
1119 	}
1120 
1121 	host->data = (struct meson_mmc_data *)
1122 		of_device_get_match_data(&pdev->dev);
1123 	if (!host->data) {
1124 		ret = -EINVAL;
1125 		goto free_host;
1126 	}
1127 
1128 	ret = device_reset_optional(&pdev->dev);
1129 	if (ret)
1130 		return dev_err_probe(&pdev->dev, ret, "device reset failed\n");
1131 
1132 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1133 	host->regs = devm_ioremap_resource(&pdev->dev, res);
1134 	if (IS_ERR(host->regs)) {
1135 		ret = PTR_ERR(host->regs);
1136 		goto free_host;
1137 	}
1138 
1139 	host->irq = platform_get_irq(pdev, 0);
1140 	if (host->irq <= 0) {
1141 		ret = -EINVAL;
1142 		goto free_host;
1143 	}
1144 
1145 	host->pinctrl = devm_pinctrl_get(&pdev->dev);
1146 	if (IS_ERR(host->pinctrl)) {
1147 		ret = PTR_ERR(host->pinctrl);
1148 		goto free_host;
1149 	}
1150 
1151 	host->pins_clk_gate = pinctrl_lookup_state(host->pinctrl,
1152 						   "clk-gate");
1153 	if (IS_ERR(host->pins_clk_gate)) {
1154 		dev_warn(&pdev->dev,
1155 			 "can't get clk-gate pinctrl, using clk_stop bit\n");
1156 		host->pins_clk_gate = NULL;
1157 	}
1158 
1159 	host->core_clk = devm_clk_get(&pdev->dev, "core");
1160 	if (IS_ERR(host->core_clk)) {
1161 		ret = PTR_ERR(host->core_clk);
1162 		goto free_host;
1163 	}
1164 
1165 	ret = clk_prepare_enable(host->core_clk);
1166 	if (ret)
1167 		goto free_host;
1168 
1169 	ret = meson_mmc_clk_init(host);
1170 	if (ret)
1171 		goto err_core_clk;
1172 
1173 	/* set config to sane default */
1174 	meson_mmc_cfg_init(host);
1175 
1176 	/* Stop execution */
1177 	writel(0, host->regs + SD_EMMC_START);
1178 
1179 	/* clear, ack and enable interrupts */
1180 	writel(0, host->regs + SD_EMMC_IRQ_EN);
1181 	writel(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN,
1182 	       host->regs + SD_EMMC_STATUS);
1183 	writel(IRQ_CRC_ERR | IRQ_TIMEOUTS | IRQ_END_OF_CHAIN,
1184 	       host->regs + SD_EMMC_IRQ_EN);
1185 
1186 	ret = request_threaded_irq(host->irq, meson_mmc_irq,
1187 				   meson_mmc_irq_thread, IRQF_ONESHOT,
1188 				   dev_name(&pdev->dev), host);
1189 	if (ret)
1190 		goto err_init_clk;
1191 
1192 	mmc->caps |= MMC_CAP_CMD23;
1193 	if (host->dram_access_quirk) {
1194 		/* Limit segments to 1 due to low available sram memory */
1195 		mmc->max_segs = 1;
1196 		/* Limit to the available sram memory */
1197 		mmc->max_blk_count = SD_EMMC_SRAM_DATA_BUF_LEN /
1198 				     mmc->max_blk_size;
1199 	} else {
1200 		mmc->max_blk_count = CMD_CFG_LENGTH_MASK;
1201 		mmc->max_segs = SD_EMMC_DESC_BUF_LEN /
1202 				sizeof(struct sd_emmc_desc);
1203 	}
1204 	mmc->max_req_size = mmc->max_blk_count * mmc->max_blk_size;
1205 	mmc->max_seg_size = mmc->max_req_size;
1206 
1207 	/*
1208 	 * At the moment, we don't know how to reliably enable HS400.
1209 	 * From the different datasheets, it is not even clear if this mode
1210 	 * is officially supported by any of the SoCs
1211 	 */
1212 	mmc->caps2 &= ~MMC_CAP2_HS400;
1213 
1214 	if (host->dram_access_quirk) {
1215 		/*
1216 		 * The MMC Controller embeds 1,5KiB of internal SRAM
1217 		 * that can be used to be used as bounce buffer.
1218 		 * In the case of the G12A SDIO controller, use these
1219 		 * instead of the DDR memory
1220 		 */
1221 		host->bounce_buf_size = SD_EMMC_SRAM_DATA_BUF_LEN;
1222 		host->bounce_iomem_buf = host->regs + SD_EMMC_SRAM_DATA_BUF_OFF;
1223 		host->bounce_dma_addr = res->start + SD_EMMC_SRAM_DATA_BUF_OFF;
1224 	} else {
1225 		/* data bounce buffer */
1226 		host->bounce_buf_size = mmc->max_req_size;
1227 		host->bounce_buf =
1228 			dma_alloc_coherent(host->dev, host->bounce_buf_size,
1229 					   &host->bounce_dma_addr, GFP_KERNEL);
1230 		if (host->bounce_buf == NULL) {
1231 			dev_err(host->dev, "Unable to map allocate DMA bounce buffer.\n");
1232 			ret = -ENOMEM;
1233 			goto err_free_irq;
1234 		}
1235 	}
1236 
1237 	host->descs = dma_alloc_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
1238 		      &host->descs_dma_addr, GFP_KERNEL);
1239 	if (!host->descs) {
1240 		dev_err(host->dev, "Allocating descriptor DMA buffer failed\n");
1241 		ret = -ENOMEM;
1242 		goto err_bounce_buf;
1243 	}
1244 
1245 	mmc->ops = &meson_mmc_ops;
1246 	mmc_add_host(mmc);
1247 
1248 	return 0;
1249 
1250 err_bounce_buf:
1251 	if (!host->dram_access_quirk)
1252 		dma_free_coherent(host->dev, host->bounce_buf_size,
1253 				  host->bounce_buf, host->bounce_dma_addr);
1254 err_free_irq:
1255 	free_irq(host->irq, host);
1256 err_init_clk:
1257 	clk_disable_unprepare(host->mmc_clk);
1258 err_core_clk:
1259 	clk_disable_unprepare(host->core_clk);
1260 free_host:
1261 	mmc_free_host(mmc);
1262 	return ret;
1263 }
1264 
1265 static int meson_mmc_remove(struct platform_device *pdev)
1266 {
1267 	struct meson_host *host = dev_get_drvdata(&pdev->dev);
1268 
1269 	mmc_remove_host(host->mmc);
1270 
1271 	/* disable interrupts */
1272 	writel(0, host->regs + SD_EMMC_IRQ_EN);
1273 	free_irq(host->irq, host);
1274 
1275 	dma_free_coherent(host->dev, SD_EMMC_DESC_BUF_LEN,
1276 			  host->descs, host->descs_dma_addr);
1277 
1278 	if (!host->dram_access_quirk)
1279 		dma_free_coherent(host->dev, host->bounce_buf_size,
1280 				  host->bounce_buf, host->bounce_dma_addr);
1281 
1282 	clk_disable_unprepare(host->mmc_clk);
1283 	clk_disable_unprepare(host->core_clk);
1284 
1285 	mmc_free_host(host->mmc);
1286 	return 0;
1287 }
1288 
1289 static const struct meson_mmc_data meson_gx_data = {
1290 	.tx_delay_mask	= CLK_V2_TX_DELAY_MASK,
1291 	.rx_delay_mask	= CLK_V2_RX_DELAY_MASK,
1292 	.always_on	= CLK_V2_ALWAYS_ON,
1293 	.adjust		= SD_EMMC_ADJUST,
1294 };
1295 
1296 static const struct meson_mmc_data meson_axg_data = {
1297 	.tx_delay_mask	= CLK_V3_TX_DELAY_MASK,
1298 	.rx_delay_mask	= CLK_V3_RX_DELAY_MASK,
1299 	.always_on	= CLK_V3_ALWAYS_ON,
1300 	.adjust		= SD_EMMC_V3_ADJUST,
1301 };
1302 
1303 static const struct of_device_id meson_mmc_of_match[] = {
1304 	{ .compatible = "amlogic,meson-gx-mmc",		.data = &meson_gx_data },
1305 	{ .compatible = "amlogic,meson-gxbb-mmc", 	.data = &meson_gx_data },
1306 	{ .compatible = "amlogic,meson-gxl-mmc",	.data = &meson_gx_data },
1307 	{ .compatible = "amlogic,meson-gxm-mmc",	.data = &meson_gx_data },
1308 	{ .compatible = "amlogic,meson-axg-mmc",	.data = &meson_axg_data },
1309 	{}
1310 };
1311 MODULE_DEVICE_TABLE(of, meson_mmc_of_match);
1312 
1313 static struct platform_driver meson_mmc_driver = {
1314 	.probe		= meson_mmc_probe,
1315 	.remove		= meson_mmc_remove,
1316 	.driver		= {
1317 		.name = DRIVER_NAME,
1318 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
1319 		.of_match_table = meson_mmc_of_match,
1320 	},
1321 };
1322 
1323 module_platform_driver(meson_mmc_driver);
1324 
1325 MODULE_DESCRIPTION("Amlogic S905*/GX*/AXG SD/eMMC driver");
1326 MODULE_AUTHOR("Kevin Hilman <khilman@baylibre.com>");
1327 MODULE_LICENSE("GPL v2");
1328