xref: /openbmc/linux/drivers/mmc/host/meson-mx-sdio.c (revision d3964221)
1 /*
2  * meson-mx-sdio.c - Meson6, Meson8 and Meson8b SDIO/MMC Host Controller
3  *
4  * Copyright (C) 2015 Endless Mobile, Inc.
5  * Author: Carlo Caione <carlo@endlessm.com>
6  * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License as published by
10  * the Free Software Foundation; either version 2 of the License, or (at
11  * your option) any later version.
12  */
13 
14 #include <linux/bitfield.h>
15 #include <linux/clk.h>
16 #include <linux/clk-provider.h>
17 #include <linux/delay.h>
18 #include <linux/device.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/module.h>
21 #include <linux/interrupt.h>
22 #include <linux/ioport.h>
23 #include <linux/platform_device.h>
24 #include <linux/of_platform.h>
25 #include <linux/timer.h>
26 #include <linux/types.h>
27 
28 #include <linux/mmc/host.h>
29 #include <linux/mmc/mmc.h>
30 #include <linux/mmc/sdio.h>
31 #include <linux/mmc/slot-gpio.h>
32 
33 #define MESON_MX_SDIO_ARGU					0x00
34 
35 #define MESON_MX_SDIO_SEND					0x04
36 	#define MESON_MX_SDIO_SEND_COMMAND_INDEX_MASK		GENMASK(7, 0)
37 	#define MESON_MX_SDIO_SEND_CMD_RESP_BITS_MASK		GENMASK(15, 8)
38 	#define MESON_MX_SDIO_SEND_RESP_WITHOUT_CRC7		BIT(16)
39 	#define MESON_MX_SDIO_SEND_RESP_HAS_DATA		BIT(17)
40 	#define MESON_MX_SDIO_SEND_RESP_CRC7_FROM_8		BIT(18)
41 	#define MESON_MX_SDIO_SEND_CHECK_DAT0_BUSY		BIT(19)
42 	#define MESON_MX_SDIO_SEND_DATA				BIT(20)
43 	#define MESON_MX_SDIO_SEND_USE_INT_WINDOW		BIT(21)
44 	#define MESON_MX_SDIO_SEND_REPEAT_PACKAGE_TIMES_MASK	GENMASK(31, 24)
45 
46 #define MESON_MX_SDIO_CONF					0x08
47 	#define MESON_MX_SDIO_CONF_CMD_CLK_DIV_SHIFT		0
48 	#define MESON_MX_SDIO_CONF_CMD_CLK_DIV_WIDTH		10
49 	#define MESON_MX_SDIO_CONF_CMD_DISABLE_CRC		BIT(10)
50 	#define MESON_MX_SDIO_CONF_CMD_OUT_AT_POSITIVE_EDGE	BIT(11)
51 	#define MESON_MX_SDIO_CONF_CMD_ARGUMENT_BITS_MASK	GENMASK(17, 12)
52 	#define MESON_MX_SDIO_CONF_RESP_LATCH_AT_NEGATIVE_EDGE	BIT(18)
53 	#define MESON_MX_SDIO_CONF_DATA_LATCH_AT_NEGATIVE_EDGE	BIT(19)
54 	#define MESON_MX_SDIO_CONF_BUS_WIDTH			BIT(20)
55 	#define MESON_MX_SDIO_CONF_M_ENDIAN_MASK		GENMASK(22, 21)
56 	#define MESON_MX_SDIO_CONF_WRITE_NWR_MASK		GENMASK(28, 23)
57 	#define MESON_MX_SDIO_CONF_WRITE_CRC_OK_STATUS_MASK	GENMASK(31, 29)
58 
59 #define MESON_MX_SDIO_IRQS					0x0c
60 	#define MESON_MX_SDIO_IRQS_STATUS_STATE_MACHINE_MASK	GENMASK(3, 0)
61 	#define MESON_MX_SDIO_IRQS_CMD_BUSY			BIT(4)
62 	#define MESON_MX_SDIO_IRQS_RESP_CRC7_OK			BIT(5)
63 	#define MESON_MX_SDIO_IRQS_DATA_READ_CRC16_OK		BIT(6)
64 	#define MESON_MX_SDIO_IRQS_DATA_WRITE_CRC16_OK		BIT(7)
65 	#define MESON_MX_SDIO_IRQS_IF_INT			BIT(8)
66 	#define MESON_MX_SDIO_IRQS_CMD_INT			BIT(9)
67 	#define MESON_MX_SDIO_IRQS_STATUS_INFO_MASK		GENMASK(15, 12)
68 	#define MESON_MX_SDIO_IRQS_TIMING_OUT_INT		BIT(16)
69 	#define MESON_MX_SDIO_IRQS_AMRISC_TIMING_OUT_INT_EN	BIT(17)
70 	#define MESON_MX_SDIO_IRQS_ARC_TIMING_OUT_INT_EN	BIT(18)
71 	#define MESON_MX_SDIO_IRQS_TIMING_OUT_COUNT_MASK	GENMASK(31, 19)
72 
73 #define MESON_MX_SDIO_IRQC					0x10
74 	#define MESON_MX_SDIO_IRQC_ARC_IF_INT_EN		BIT(3)
75 	#define MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN		BIT(4)
76 	#define MESON_MX_SDIO_IRQC_IF_CONFIG_MASK		GENMASK(7, 6)
77 	#define MESON_MX_SDIO_IRQC_FORCE_DATA_CLK		BIT(8)
78 	#define MESON_MX_SDIO_IRQC_FORCE_DATA_CMD		BIT(9)
79 	#define MESON_MX_SDIO_IRQC_FORCE_DATA_DAT_MASK		GENMASK(10, 13)
80 	#define MESON_MX_SDIO_IRQC_SOFT_RESET			BIT(15)
81 	#define MESON_MX_SDIO_IRQC_FORCE_HALT			BIT(30)
82 	#define MESON_MX_SDIO_IRQC_HALT_HOLE			BIT(31)
83 
84 #define MESON_MX_SDIO_MULT					0x14
85 	#define MESON_MX_SDIO_MULT_PORT_SEL_MASK		GENMASK(1, 0)
86 	#define MESON_MX_SDIO_MULT_MEMORY_STICK_ENABLE		BIT(2)
87 	#define MESON_MX_SDIO_MULT_MEMORY_STICK_SCLK_ALWAYS	BIT(3)
88 	#define MESON_MX_SDIO_MULT_STREAM_ENABLE		BIT(4)
89 	#define MESON_MX_SDIO_MULT_STREAM_8BITS_MODE		BIT(5)
90 	#define MESON_MX_SDIO_MULT_WR_RD_OUT_INDEX		BIT(8)
91 	#define MESON_MX_SDIO_MULT_DAT0_DAT1_SWAPPED		BIT(10)
92 	#define MESON_MX_SDIO_MULT_DAT1_DAT0_SWAPPED		BIT(11)
93 	#define MESON_MX_SDIO_MULT_RESP_READ_INDEX_MASK		GENMASK(15, 12)
94 
95 #define MESON_MX_SDIO_ADDR					0x18
96 
97 #define MESON_MX_SDIO_EXT					0x1c
98 	#define MESON_MX_SDIO_EXT_DATA_RW_NUMBER_MASK		GENMASK(29, 16)
99 
100 #define MESON_MX_SDIO_BOUNCE_REQ_SIZE				(128 * 1024)
101 #define MESON_MX_SDIO_RESPONSE_CRC16_BITS			(16 - 1)
102 #define MESON_MX_SDIO_MAX_SLOTS					3
103 
104 struct meson_mx_mmc_host {
105 	struct device			*controller_dev;
106 
107 	struct clk			*parent_clk;
108 	struct clk			*core_clk;
109 	struct clk_divider		cfg_div;
110 	struct clk			*cfg_div_clk;
111 	struct clk_fixed_factor		fixed_factor;
112 	struct clk			*fixed_factor_clk;
113 
114 	void __iomem			*base;
115 	int				irq;
116 	spinlock_t			irq_lock;
117 
118 	struct timer_list		cmd_timeout;
119 
120 	unsigned int			slot_id;
121 	struct mmc_host			*mmc;
122 
123 	struct mmc_request		*mrq;
124 	struct mmc_command		*cmd;
125 	int				error;
126 };
127 
128 static void meson_mx_mmc_mask_bits(struct mmc_host *mmc, char reg, u32 mask,
129 				   u32 val)
130 {
131 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
132 	u32 regval;
133 
134 	regval = readl(host->base + reg);
135 	regval &= ~mask;
136 	regval |= (val & mask);
137 
138 	writel(regval, host->base + reg);
139 }
140 
141 static void meson_mx_mmc_soft_reset(struct meson_mx_mmc_host *host)
142 {
143 	writel(MESON_MX_SDIO_IRQC_SOFT_RESET, host->base + MESON_MX_SDIO_IRQC);
144 	udelay(2);
145 }
146 
147 static struct mmc_command *meson_mx_mmc_get_next_cmd(struct mmc_command *cmd)
148 {
149 	if (cmd->opcode == MMC_SET_BLOCK_COUNT && !cmd->error)
150 		return cmd->mrq->cmd;
151 	else if (mmc_op_multi(cmd->opcode) &&
152 		 (!cmd->mrq->sbc || cmd->error || cmd->data->error))
153 		return cmd->mrq->stop;
154 	else
155 		return NULL;
156 }
157 
158 static void meson_mx_mmc_start_cmd(struct mmc_host *mmc,
159 				   struct mmc_command *cmd)
160 {
161 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
162 	unsigned int pack_size;
163 	unsigned long irqflags, timeout;
164 	u32 mult, send = 0, ext = 0;
165 
166 	host->cmd = cmd;
167 
168 	if (cmd->busy_timeout)
169 		timeout = msecs_to_jiffies(cmd->busy_timeout);
170 	else
171 		timeout = msecs_to_jiffies(1000);
172 
173 	switch (mmc_resp_type(cmd)) {
174 	case MMC_RSP_R1:
175 	case MMC_RSP_R1B:
176 	case MMC_RSP_R3:
177 		/* 7 (CMD) + 32 (response) + 7 (CRC) -1 */
178 		send |= FIELD_PREP(MESON_MX_SDIO_SEND_CMD_RESP_BITS_MASK, 45);
179 		break;
180 	case MMC_RSP_R2:
181 		/* 7 (CMD) + 120 (response) + 7 (CRC) -1 */
182 		send |= FIELD_PREP(MESON_MX_SDIO_SEND_CMD_RESP_BITS_MASK, 133);
183 		send |= MESON_MX_SDIO_SEND_RESP_CRC7_FROM_8;
184 		break;
185 	default:
186 		break;
187 	}
188 
189 	if (!(cmd->flags & MMC_RSP_CRC))
190 		send |= MESON_MX_SDIO_SEND_RESP_WITHOUT_CRC7;
191 
192 	if (cmd->flags & MMC_RSP_BUSY)
193 		send |= MESON_MX_SDIO_SEND_CHECK_DAT0_BUSY;
194 
195 	if (cmd->data) {
196 		send |= FIELD_PREP(MESON_MX_SDIO_SEND_REPEAT_PACKAGE_TIMES_MASK,
197 				   (cmd->data->blocks - 1));
198 
199 		pack_size = cmd->data->blksz * BITS_PER_BYTE;
200 		if (mmc->ios.bus_width == MMC_BUS_WIDTH_4)
201 			pack_size += MESON_MX_SDIO_RESPONSE_CRC16_BITS * 4;
202 		else
203 			pack_size += MESON_MX_SDIO_RESPONSE_CRC16_BITS * 1;
204 
205 		ext |= FIELD_PREP(MESON_MX_SDIO_EXT_DATA_RW_NUMBER_MASK,
206 				  pack_size);
207 
208 		if (cmd->data->flags & MMC_DATA_WRITE)
209 			send |= MESON_MX_SDIO_SEND_DATA;
210 		else
211 			send |= MESON_MX_SDIO_SEND_RESP_HAS_DATA;
212 
213 		cmd->data->bytes_xfered = 0;
214 	}
215 
216 	send |= FIELD_PREP(MESON_MX_SDIO_SEND_COMMAND_INDEX_MASK,
217 			   (0x40 | cmd->opcode));
218 
219 	spin_lock_irqsave(&host->irq_lock, irqflags);
220 
221 	mult = readl(host->base + MESON_MX_SDIO_MULT);
222 	mult &= ~MESON_MX_SDIO_MULT_PORT_SEL_MASK;
223 	mult |= FIELD_PREP(MESON_MX_SDIO_MULT_PORT_SEL_MASK, host->slot_id);
224 	mult |= BIT(31);
225 	writel(mult, host->base + MESON_MX_SDIO_MULT);
226 
227 	/* enable the CMD done interrupt */
228 	meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_IRQC,
229 			       MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN,
230 			       MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN);
231 
232 	/* clear pending interrupts */
233 	meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_IRQS,
234 			       MESON_MX_SDIO_IRQS_CMD_INT,
235 			       MESON_MX_SDIO_IRQS_CMD_INT);
236 
237 	writel(cmd->arg, host->base + MESON_MX_SDIO_ARGU);
238 	writel(ext, host->base + MESON_MX_SDIO_EXT);
239 	writel(send, host->base + MESON_MX_SDIO_SEND);
240 
241 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
242 
243 	mod_timer(&host->cmd_timeout, jiffies + timeout);
244 }
245 
246 static void meson_mx_mmc_request_done(struct meson_mx_mmc_host *host)
247 {
248 	struct mmc_request *mrq;
249 
250 	mrq = host->mrq;
251 
252 	host->mrq = NULL;
253 	host->cmd = NULL;
254 
255 	mmc_request_done(host->mmc, mrq);
256 }
257 
258 static void meson_mx_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
259 {
260 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
261 	unsigned short vdd = ios->vdd;
262 	unsigned long clk_rate = ios->clock;
263 
264 	switch (ios->bus_width) {
265 	case MMC_BUS_WIDTH_1:
266 		meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_CONF,
267 				       MESON_MX_SDIO_CONF_BUS_WIDTH, 0);
268 		break;
269 
270 	case MMC_BUS_WIDTH_4:
271 		meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_CONF,
272 				       MESON_MX_SDIO_CONF_BUS_WIDTH,
273 				       MESON_MX_SDIO_CONF_BUS_WIDTH);
274 		break;
275 
276 	case MMC_BUS_WIDTH_8:
277 	default:
278 		dev_err(mmc_dev(mmc), "unsupported bus width: %d\n",
279 			ios->bus_width);
280 		host->error = -EINVAL;
281 		return;
282 	}
283 
284 	host->error = clk_set_rate(host->cfg_div_clk, ios->clock);
285 	if (host->error) {
286 		dev_warn(mmc_dev(mmc),
287 				"failed to set MMC clock to %lu: %d\n",
288 				clk_rate, host->error);
289 		return;
290 	}
291 
292 	mmc->actual_clock = clk_get_rate(host->cfg_div_clk);
293 
294 	switch (ios->power_mode) {
295 	case MMC_POWER_OFF:
296 		vdd = 0;
297 		/* fall-through: */
298 	case MMC_POWER_UP:
299 		if (!IS_ERR(mmc->supply.vmmc)) {
300 			host->error = mmc_regulator_set_ocr(mmc,
301 							    mmc->supply.vmmc,
302 							    vdd);
303 			if (host->error)
304 				return;
305 		}
306 		break;
307 	}
308 }
309 
310 static int meson_mx_mmc_map_dma(struct mmc_host *mmc, struct mmc_request *mrq)
311 {
312 	struct mmc_data *data = mrq->data;
313 	int dma_len;
314 	struct scatterlist *sg;
315 
316 	if (!data)
317 		return 0;
318 
319 	sg = data->sg;
320 	if (sg->offset & 3 || sg->length & 3) {
321 		dev_err(mmc_dev(mmc),
322 			"unaligned scatterlist: offset %x length %d\n",
323 			sg->offset, sg->length);
324 		return -EINVAL;
325 	}
326 
327 	dma_len = dma_map_sg(mmc_dev(mmc), data->sg, data->sg_len,
328 			     mmc_get_dma_dir(data));
329 	if (dma_len <= 0) {
330 		dev_err(mmc_dev(mmc), "dma_map_sg failed\n");
331 		return -ENOMEM;
332 	}
333 
334 	return 0;
335 }
336 
337 static void meson_mx_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
338 {
339 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
340 	struct mmc_command *cmd = mrq->cmd;
341 
342 	if (!host->error)
343 		host->error = meson_mx_mmc_map_dma(mmc, mrq);
344 
345 	if (host->error) {
346 		cmd->error = host->error;
347 		mmc_request_done(mmc, mrq);
348 		return;
349 	}
350 
351 	host->mrq = mrq;
352 
353 	if (mrq->data)
354 		writel(sg_dma_address(mrq->data->sg),
355 		       host->base + MESON_MX_SDIO_ADDR);
356 
357 	if (mrq->sbc)
358 		meson_mx_mmc_start_cmd(mmc, mrq->sbc);
359 	else
360 		meson_mx_mmc_start_cmd(mmc, mrq->cmd);
361 }
362 
363 static int meson_mx_mmc_card_busy(struct mmc_host *mmc)
364 {
365 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
366 	u32 irqc = readl(host->base + MESON_MX_SDIO_IRQC);
367 
368 	return !!(irqc & MESON_MX_SDIO_IRQC_FORCE_DATA_DAT_MASK);
369 }
370 
371 static void meson_mx_mmc_read_response(struct mmc_host *mmc,
372 				       struct mmc_command *cmd)
373 {
374 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
375 	u32 mult;
376 	int i, resp[4];
377 
378 	mult = readl(host->base + MESON_MX_SDIO_MULT);
379 	mult |= MESON_MX_SDIO_MULT_WR_RD_OUT_INDEX;
380 	mult &= ~MESON_MX_SDIO_MULT_RESP_READ_INDEX_MASK;
381 	mult |= FIELD_PREP(MESON_MX_SDIO_MULT_RESP_READ_INDEX_MASK, 0);
382 	writel(mult, host->base + MESON_MX_SDIO_MULT);
383 
384 	if (cmd->flags & MMC_RSP_136) {
385 		for (i = 0; i <= 3; i++)
386 			resp[3 - i] = readl(host->base + MESON_MX_SDIO_ARGU);
387 		cmd->resp[0] = (resp[0] << 8) | ((resp[1] >> 24) & 0xff);
388 		cmd->resp[1] = (resp[1] << 8) | ((resp[2] >> 24) & 0xff);
389 		cmd->resp[2] = (resp[2] << 8) | ((resp[3] >> 24) & 0xff);
390 		cmd->resp[3] = (resp[3] << 8);
391 	} else if (cmd->flags & MMC_RSP_PRESENT) {
392 		cmd->resp[0] = readl(host->base + MESON_MX_SDIO_ARGU);
393 	}
394 }
395 
396 static irqreturn_t meson_mx_mmc_process_cmd_irq(struct meson_mx_mmc_host *host,
397 						u32 irqs, u32 send)
398 {
399 	struct mmc_command *cmd = host->cmd;
400 
401 	/*
402 	 * NOTE: even though it shouldn't happen we sometimes get command
403 	 * interrupts twice (at least this is what it looks like). Ideally
404 	 * we find out why this happens and warn here as soon as it occurs.
405 	 */
406 	if (!cmd)
407 		return IRQ_HANDLED;
408 
409 	cmd->error = 0;
410 	meson_mx_mmc_read_response(host->mmc, cmd);
411 
412 	if (cmd->data) {
413 		if (!((irqs & MESON_MX_SDIO_IRQS_DATA_READ_CRC16_OK) ||
414 		      (irqs & MESON_MX_SDIO_IRQS_DATA_WRITE_CRC16_OK)))
415 			cmd->error = -EILSEQ;
416 	} else {
417 		if (!((irqs & MESON_MX_SDIO_IRQS_RESP_CRC7_OK) ||
418 		      (send & MESON_MX_SDIO_SEND_RESP_WITHOUT_CRC7)))
419 			cmd->error = -EILSEQ;
420 	}
421 
422 	return IRQ_WAKE_THREAD;
423 }
424 
425 static irqreturn_t meson_mx_mmc_irq(int irq, void *data)
426 {
427 	struct meson_mx_mmc_host *host = (void *) data;
428 	u32 irqs, send;
429 	unsigned long irqflags;
430 	irqreturn_t ret;
431 
432 	spin_lock_irqsave(&host->irq_lock, irqflags);
433 
434 	irqs = readl(host->base + MESON_MX_SDIO_IRQS);
435 	send = readl(host->base + MESON_MX_SDIO_SEND);
436 
437 	if (irqs & MESON_MX_SDIO_IRQS_CMD_INT)
438 		ret = meson_mx_mmc_process_cmd_irq(host, irqs, send);
439 	else
440 		ret = IRQ_HANDLED;
441 
442 	/* finally ACK all pending interrupts */
443 	writel(irqs, host->base + MESON_MX_SDIO_IRQS);
444 
445 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
446 
447 	return ret;
448 }
449 
450 static irqreturn_t meson_mx_mmc_irq_thread(int irq, void *irq_data)
451 {
452 	struct meson_mx_mmc_host *host = (void *) irq_data;
453 	struct mmc_command *cmd = host->cmd, *next_cmd;
454 
455 	if (WARN_ON(!cmd))
456 		return IRQ_HANDLED;
457 
458 	del_timer_sync(&host->cmd_timeout);
459 
460 	if (cmd->data) {
461 		dma_unmap_sg(mmc_dev(host->mmc), cmd->data->sg,
462 				cmd->data->sg_len,
463 				mmc_get_dma_dir(cmd->data));
464 
465 		cmd->data->bytes_xfered = cmd->data->blksz * cmd->data->blocks;
466 	}
467 
468 	next_cmd = meson_mx_mmc_get_next_cmd(cmd);
469 	if (next_cmd)
470 		meson_mx_mmc_start_cmd(host->mmc, next_cmd);
471 	else
472 		meson_mx_mmc_request_done(host);
473 
474 	return IRQ_HANDLED;
475 }
476 
477 static void meson_mx_mmc_timeout(struct timer_list *t)
478 {
479 	struct meson_mx_mmc_host *host = from_timer(host, t, cmd_timeout);
480 	unsigned long irqflags;
481 	u32 irqc;
482 
483 	spin_lock_irqsave(&host->irq_lock, irqflags);
484 
485 	/* disable the CMD interrupt */
486 	irqc = readl(host->base + MESON_MX_SDIO_IRQC);
487 	irqc &= ~MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN;
488 	writel(irqc, host->base + MESON_MX_SDIO_IRQC);
489 
490 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
491 
492 	/*
493 	 * skip the timeout handling if the interrupt handler already processed
494 	 * the command.
495 	 */
496 	if (!host->cmd)
497 		return;
498 
499 	dev_dbg(mmc_dev(host->mmc),
500 		"Timeout on CMD%u (IRQS = 0x%08x, ARGU = 0x%08x)\n",
501 		host->cmd->opcode, readl(host->base + MESON_MX_SDIO_IRQS),
502 		readl(host->base + MESON_MX_SDIO_ARGU));
503 
504 	host->cmd->error = -ETIMEDOUT;
505 
506 	meson_mx_mmc_request_done(host);
507 }
508 
509 static struct mmc_host_ops meson_mx_mmc_ops = {
510 	.request		= meson_mx_mmc_request,
511 	.set_ios		= meson_mx_mmc_set_ios,
512 	.card_busy		= meson_mx_mmc_card_busy,
513 	.get_cd			= mmc_gpio_get_cd,
514 	.get_ro			= mmc_gpio_get_ro,
515 };
516 
517 static struct platform_device *meson_mx_mmc_slot_pdev(struct device *parent)
518 {
519 	struct device_node *slot_node;
520 
521 	/*
522 	 * TODO: the MMC core framework currently does not support
523 	 * controllers with multiple slots properly. So we only register
524 	 * the first slot for now
525 	 */
526 	slot_node = of_find_compatible_node(parent->of_node, NULL, "mmc-slot");
527 	if (!slot_node) {
528 		dev_warn(parent, "no 'mmc-slot' sub-node found\n");
529 		return ERR_PTR(-ENOENT);
530 	}
531 
532 	return of_platform_device_create(slot_node, NULL, parent);
533 }
534 
535 static int meson_mx_mmc_add_host(struct meson_mx_mmc_host *host)
536 {
537 	struct mmc_host *mmc = host->mmc;
538 	struct device *slot_dev = mmc_dev(mmc);
539 	int ret;
540 
541 	if (of_property_read_u32(slot_dev->of_node, "reg", &host->slot_id)) {
542 		dev_err(slot_dev, "missing 'reg' property\n");
543 		return -EINVAL;
544 	}
545 
546 	if (host->slot_id >= MESON_MX_SDIO_MAX_SLOTS) {
547 		dev_err(slot_dev, "invalid 'reg' property value %d\n",
548 			host->slot_id);
549 		return -EINVAL;
550 	}
551 
552 	/* Get regulators and the supported OCR mask */
553 	ret = mmc_regulator_get_supply(mmc);
554 	if (ret)
555 		return ret;
556 
557 	mmc->max_req_size = MESON_MX_SDIO_BOUNCE_REQ_SIZE;
558 	mmc->max_seg_size = mmc->max_req_size;
559 	mmc->max_blk_count =
560 		FIELD_GET(MESON_MX_SDIO_SEND_REPEAT_PACKAGE_TIMES_MASK,
561 			  0xffffffff);
562 	mmc->max_blk_size = FIELD_GET(MESON_MX_SDIO_EXT_DATA_RW_NUMBER_MASK,
563 				      0xffffffff);
564 	mmc->max_blk_size -= (4 * MESON_MX_SDIO_RESPONSE_CRC16_BITS);
565 	mmc->max_blk_size /= BITS_PER_BYTE;
566 
567 	/* Get the min and max supported clock rates */
568 	mmc->f_min = clk_round_rate(host->cfg_div_clk, 1);
569 	mmc->f_max = clk_round_rate(host->cfg_div_clk,
570 				    clk_get_rate(host->parent_clk));
571 
572 	mmc->caps |= MMC_CAP_ERASE | MMC_CAP_CMD23;
573 	mmc->ops = &meson_mx_mmc_ops;
574 
575 	ret = mmc_of_parse(mmc);
576 	if (ret)
577 		return ret;
578 
579 	ret = mmc_add_host(mmc);
580 	if (ret)
581 		return ret;
582 
583 	return 0;
584 }
585 
586 static int meson_mx_mmc_register_clks(struct meson_mx_mmc_host *host)
587 {
588 	struct clk_init_data init;
589 	const char *clk_div_parent, *clk_fixed_factor_parent;
590 
591 	clk_fixed_factor_parent = __clk_get_name(host->parent_clk);
592 	init.name = devm_kasprintf(host->controller_dev, GFP_KERNEL,
593 				   "%s#fixed_factor",
594 				   dev_name(host->controller_dev));
595 	init.ops = &clk_fixed_factor_ops;
596 	init.flags = 0;
597 	init.parent_names = &clk_fixed_factor_parent;
598 	init.num_parents = 1;
599 	host->fixed_factor.div = 2;
600 	host->fixed_factor.mult = 1;
601 	host->fixed_factor.hw.init = &init;
602 
603 	host->fixed_factor_clk = devm_clk_register(host->controller_dev,
604 						 &host->fixed_factor.hw);
605 	if (WARN_ON(IS_ERR(host->fixed_factor_clk)))
606 		return PTR_ERR(host->fixed_factor_clk);
607 
608 	clk_div_parent = __clk_get_name(host->fixed_factor_clk);
609 	init.name = devm_kasprintf(host->controller_dev, GFP_KERNEL,
610 				   "%s#div", dev_name(host->controller_dev));
611 	init.ops = &clk_divider_ops;
612 	init.flags = CLK_SET_RATE_PARENT;
613 	init.parent_names = &clk_div_parent;
614 	init.num_parents = 1;
615 	host->cfg_div.reg = host->base + MESON_MX_SDIO_CONF;
616 	host->cfg_div.shift = MESON_MX_SDIO_CONF_CMD_CLK_DIV_SHIFT;
617 	host->cfg_div.width = MESON_MX_SDIO_CONF_CMD_CLK_DIV_WIDTH;
618 	host->cfg_div.hw.init = &init;
619 	host->cfg_div.flags = CLK_DIVIDER_ALLOW_ZERO;
620 
621 	host->cfg_div_clk = devm_clk_register(host->controller_dev,
622 					      &host->cfg_div.hw);
623 	if (WARN_ON(IS_ERR(host->cfg_div_clk)))
624 		return PTR_ERR(host->cfg_div_clk);
625 
626 	return 0;
627 }
628 
629 static int meson_mx_mmc_probe(struct platform_device *pdev)
630 {
631 	struct platform_device *slot_pdev;
632 	struct mmc_host *mmc;
633 	struct meson_mx_mmc_host *host;
634 	struct resource *res;
635 	int ret, irq;
636 	u32 conf;
637 
638 	slot_pdev = meson_mx_mmc_slot_pdev(&pdev->dev);
639 	if (!slot_pdev)
640 		return -ENODEV;
641 	else if (IS_ERR(slot_pdev))
642 		return PTR_ERR(slot_pdev);
643 
644 	mmc = mmc_alloc_host(sizeof(*host), &slot_pdev->dev);
645 	if (!mmc) {
646 		ret = -ENOMEM;
647 		goto error_unregister_slot_pdev;
648 	}
649 
650 	host = mmc_priv(mmc);
651 	host->mmc = mmc;
652 	host->controller_dev = &pdev->dev;
653 
654 	spin_lock_init(&host->irq_lock);
655 	timer_setup(&host->cmd_timeout, meson_mx_mmc_timeout, 0);
656 
657 	platform_set_drvdata(pdev, host);
658 
659 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
660 	host->base = devm_ioremap_resource(host->controller_dev, res);
661 	if (IS_ERR(host->base)) {
662 		ret = PTR_ERR(host->base);
663 		goto error_free_mmc;
664 	}
665 
666 	irq = platform_get_irq(pdev, 0);
667 	ret = devm_request_threaded_irq(host->controller_dev, irq,
668 					meson_mx_mmc_irq,
669 					meson_mx_mmc_irq_thread, IRQF_ONESHOT,
670 					NULL, host);
671 	if (ret)
672 		goto error_free_mmc;
673 
674 	host->core_clk = devm_clk_get(host->controller_dev, "core");
675 	if (IS_ERR(host->core_clk)) {
676 		ret = PTR_ERR(host->core_clk);
677 		goto error_free_mmc;
678 	}
679 
680 	host->parent_clk = devm_clk_get(host->controller_dev, "clkin");
681 	if (IS_ERR(host->parent_clk)) {
682 		ret = PTR_ERR(host->parent_clk);
683 		goto error_free_mmc;
684 	}
685 
686 	ret = meson_mx_mmc_register_clks(host);
687 	if (ret)
688 		goto error_free_mmc;
689 
690 	ret = clk_prepare_enable(host->core_clk);
691 	if (ret) {
692 		dev_err(host->controller_dev, "Failed to enable core clock\n");
693 		goto error_free_mmc;
694 	}
695 
696 	ret = clk_prepare_enable(host->cfg_div_clk);
697 	if (ret) {
698 		dev_err(host->controller_dev, "Failed to enable MMC clock\n");
699 		goto error_disable_core_clk;
700 	}
701 
702 	conf = 0;
703 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_CMD_ARGUMENT_BITS_MASK, 39);
704 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_M_ENDIAN_MASK, 0x3);
705 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_WRITE_NWR_MASK, 0x2);
706 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_WRITE_CRC_OK_STATUS_MASK, 0x2);
707 	writel(conf, host->base + MESON_MX_SDIO_CONF);
708 
709 	meson_mx_mmc_soft_reset(host);
710 
711 	ret = meson_mx_mmc_add_host(host);
712 	if (ret)
713 		goto error_disable_clks;
714 
715 	return 0;
716 
717 error_disable_clks:
718 	clk_disable_unprepare(host->cfg_div_clk);
719 error_disable_core_clk:
720 	clk_disable_unprepare(host->core_clk);
721 error_free_mmc:
722 	mmc_free_host(mmc);
723 error_unregister_slot_pdev:
724 	of_platform_device_destroy(&slot_pdev->dev, NULL);
725 	return ret;
726 }
727 
728 static int meson_mx_mmc_remove(struct platform_device *pdev)
729 {
730 	struct meson_mx_mmc_host *host = platform_get_drvdata(pdev);
731 	struct device *slot_dev = mmc_dev(host->mmc);
732 
733 	del_timer_sync(&host->cmd_timeout);
734 
735 	mmc_remove_host(host->mmc);
736 
737 	of_platform_device_destroy(slot_dev, NULL);
738 
739 	clk_disable_unprepare(host->cfg_div_clk);
740 	clk_disable_unprepare(host->core_clk);
741 
742 	mmc_free_host(host->mmc);
743 
744 	return 0;
745 }
746 
747 static const struct of_device_id meson_mx_mmc_of_match[] = {
748 	{ .compatible = "amlogic,meson8-sdio", },
749 	{ .compatible = "amlogic,meson8b-sdio", },
750 	{ /* sentinel */ }
751 };
752 MODULE_DEVICE_TABLE(of, meson_mx_mmc_of_match);
753 
754 static struct platform_driver meson_mx_mmc_driver = {
755 	.probe   = meson_mx_mmc_probe,
756 	.remove  = meson_mx_mmc_remove,
757 	.driver  = {
758 		.name = "meson-mx-sdio",
759 		.of_match_table = of_match_ptr(meson_mx_mmc_of_match),
760 	},
761 };
762 
763 module_platform_driver(meson_mx_mmc_driver);
764 
765 MODULE_DESCRIPTION("Meson6, Meson8 and Meson8b SDIO/MMC Host Driver");
766 MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
767 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
768 MODULE_LICENSE("GPL v2");
769