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
136struct 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
144struct sd_emmc_desc {
145	u32 cmd_cfg;
146	u32 cmd_arg;
147	u32 cmd_data;
148	u32 cmd_resp;
149};
150
151struct 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
205static 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
217static 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
228static 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
277static 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
282static 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
288static 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
307static 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 */
323static 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
340static 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
353static 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 */
419static 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
507static 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
515static 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
526static 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
562static 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
581static 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
594static 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
652static 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
663static 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
688static 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
705static 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 */
744static 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
790static 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
855static 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
873static 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
907static 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
921static 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
931static 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
994out:
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
1006static 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
1023static 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
1060static 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
1075static 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
1086static 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
1110static 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
1120static void meson_mmc_ack_sdio_irq(struct mmc_host *mmc)
1121{
1122	meson_mmc_enable_sdio_irq(mmc, 1);
1123}
1124
1125static 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
1138static 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
1289err_free_irq:
1290	free_irq(host->irq, host);
1291err_init_clk:
1292	clk_disable_unprepare(host->mmc_clk);
1293	return ret;
1294}
1295
1296static 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
1309static 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
1317static 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
1325static 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};
1333MODULE_DEVICE_TABLE(of, meson_mmc_of_match);
1334
1335static 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
1345module_platform_driver(meson_mmc_driver);
1346
1347MODULE_DESCRIPTION("Amlogic S905*/GX*/AXG SD/eMMC driver");
1348MODULE_AUTHOR("Kevin Hilman <khilman@baylibre.com>");
1349MODULE_LICENSE("GPL v2");
1350