xref: /openbmc/linux/drivers/mmc/host/meson-mx-sdio.c (revision cbdf59ad)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * meson-mx-sdio.c - Meson6, Meson8 and Meson8b SDIO/MMC Host Controller
4  *
5  * Copyright (C) 2015 Endless Mobile, Inc.
6  * Author: Carlo Caione <carlo@endlessm.com>
7  * Copyright (C) 2017 Martin Blumenstingl <martin.blumenstingl@googlemail.com>
8  */
9 
10 #include <linux/bitfield.h>
11 #include <linux/clk.h>
12 #include <linux/clk-provider.h>
13 #include <linux/delay.h>
14 #include <linux/device.h>
15 #include <linux/dma-mapping.h>
16 #include <linux/module.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/ioport.h>
20 #include <linux/platform_device.h>
21 #include <linux/of_platform.h>
22 #include <linux/timer.h>
23 #include <linux/types.h>
24 
25 #include <linux/mmc/host.h>
26 #include <linux/mmc/mmc.h>
27 #include <linux/mmc/sdio.h>
28 #include <linux/mmc/slot-gpio.h>
29 
30 #define MESON_MX_SDIO_ARGU					0x00
31 
32 #define MESON_MX_SDIO_SEND					0x04
33 	#define MESON_MX_SDIO_SEND_COMMAND_INDEX_MASK		GENMASK(7, 0)
34 	#define MESON_MX_SDIO_SEND_CMD_RESP_BITS_MASK		GENMASK(15, 8)
35 	#define MESON_MX_SDIO_SEND_RESP_WITHOUT_CRC7		BIT(16)
36 	#define MESON_MX_SDIO_SEND_RESP_HAS_DATA		BIT(17)
37 	#define MESON_MX_SDIO_SEND_RESP_CRC7_FROM_8		BIT(18)
38 	#define MESON_MX_SDIO_SEND_CHECK_DAT0_BUSY		BIT(19)
39 	#define MESON_MX_SDIO_SEND_DATA				BIT(20)
40 	#define MESON_MX_SDIO_SEND_USE_INT_WINDOW		BIT(21)
41 	#define MESON_MX_SDIO_SEND_REPEAT_PACKAGE_TIMES_MASK	GENMASK(31, 24)
42 
43 #define MESON_MX_SDIO_CONF					0x08
44 	#define MESON_MX_SDIO_CONF_CMD_CLK_DIV_SHIFT		0
45 	#define MESON_MX_SDIO_CONF_CMD_CLK_DIV_WIDTH		10
46 	#define MESON_MX_SDIO_CONF_CMD_DISABLE_CRC		BIT(10)
47 	#define MESON_MX_SDIO_CONF_CMD_OUT_AT_POSITIVE_EDGE	BIT(11)
48 	#define MESON_MX_SDIO_CONF_CMD_ARGUMENT_BITS_MASK	GENMASK(17, 12)
49 	#define MESON_MX_SDIO_CONF_RESP_LATCH_AT_NEGATIVE_EDGE	BIT(18)
50 	#define MESON_MX_SDIO_CONF_DATA_LATCH_AT_NEGATIVE_EDGE	BIT(19)
51 	#define MESON_MX_SDIO_CONF_BUS_WIDTH			BIT(20)
52 	#define MESON_MX_SDIO_CONF_M_ENDIAN_MASK		GENMASK(22, 21)
53 	#define MESON_MX_SDIO_CONF_WRITE_NWR_MASK		GENMASK(28, 23)
54 	#define MESON_MX_SDIO_CONF_WRITE_CRC_OK_STATUS_MASK	GENMASK(31, 29)
55 
56 #define MESON_MX_SDIO_IRQS					0x0c
57 	#define MESON_MX_SDIO_IRQS_STATUS_STATE_MACHINE_MASK	GENMASK(3, 0)
58 	#define MESON_MX_SDIO_IRQS_CMD_BUSY			BIT(4)
59 	#define MESON_MX_SDIO_IRQS_RESP_CRC7_OK			BIT(5)
60 	#define MESON_MX_SDIO_IRQS_DATA_READ_CRC16_OK		BIT(6)
61 	#define MESON_MX_SDIO_IRQS_DATA_WRITE_CRC16_OK		BIT(7)
62 	#define MESON_MX_SDIO_IRQS_IF_INT			BIT(8)
63 	#define MESON_MX_SDIO_IRQS_CMD_INT			BIT(9)
64 	#define MESON_MX_SDIO_IRQS_STATUS_INFO_MASK		GENMASK(15, 12)
65 	#define MESON_MX_SDIO_IRQS_TIMING_OUT_INT		BIT(16)
66 	#define MESON_MX_SDIO_IRQS_AMRISC_TIMING_OUT_INT_EN	BIT(17)
67 	#define MESON_MX_SDIO_IRQS_ARC_TIMING_OUT_INT_EN	BIT(18)
68 	#define MESON_MX_SDIO_IRQS_TIMING_OUT_COUNT_MASK	GENMASK(31, 19)
69 
70 #define MESON_MX_SDIO_IRQC					0x10
71 	#define MESON_MX_SDIO_IRQC_ARC_IF_INT_EN		BIT(3)
72 	#define MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN		BIT(4)
73 	#define MESON_MX_SDIO_IRQC_IF_CONFIG_MASK		GENMASK(7, 6)
74 	#define MESON_MX_SDIO_IRQC_FORCE_DATA_CLK		BIT(8)
75 	#define MESON_MX_SDIO_IRQC_FORCE_DATA_CMD		BIT(9)
76 	#define MESON_MX_SDIO_IRQC_FORCE_DATA_DAT_MASK		GENMASK(13, 10)
77 	#define MESON_MX_SDIO_IRQC_SOFT_RESET			BIT(15)
78 	#define MESON_MX_SDIO_IRQC_FORCE_HALT			BIT(30)
79 	#define MESON_MX_SDIO_IRQC_HALT_HOLE			BIT(31)
80 
81 #define MESON_MX_SDIO_MULT					0x14
82 	#define MESON_MX_SDIO_MULT_PORT_SEL_MASK		GENMASK(1, 0)
83 	#define MESON_MX_SDIO_MULT_MEMORY_STICK_ENABLE		BIT(2)
84 	#define MESON_MX_SDIO_MULT_MEMORY_STICK_SCLK_ALWAYS	BIT(3)
85 	#define MESON_MX_SDIO_MULT_STREAM_ENABLE		BIT(4)
86 	#define MESON_MX_SDIO_MULT_STREAM_8BITS_MODE		BIT(5)
87 	#define MESON_MX_SDIO_MULT_WR_RD_OUT_INDEX		BIT(8)
88 	#define MESON_MX_SDIO_MULT_DAT0_DAT1_SWAPPED		BIT(10)
89 	#define MESON_MX_SDIO_MULT_DAT1_DAT0_SWAPPED		BIT(11)
90 	#define MESON_MX_SDIO_MULT_RESP_READ_INDEX_MASK		GENMASK(15, 12)
91 
92 #define MESON_MX_SDIO_ADDR					0x18
93 
94 #define MESON_MX_SDIO_EXT					0x1c
95 	#define MESON_MX_SDIO_EXT_DATA_RW_NUMBER_MASK		GENMASK(29, 16)
96 
97 #define MESON_MX_SDIO_BOUNCE_REQ_SIZE				(128 * 1024)
98 #define MESON_MX_SDIO_RESPONSE_CRC16_BITS			(16 - 1)
99 #define MESON_MX_SDIO_MAX_SLOTS					3
100 
101 struct meson_mx_mmc_host {
102 	struct device			*controller_dev;
103 
104 	struct clk			*parent_clk;
105 	struct clk			*core_clk;
106 	struct clk_divider		cfg_div;
107 	struct clk			*cfg_div_clk;
108 	struct clk_fixed_factor		fixed_factor;
109 	struct clk			*fixed_factor_clk;
110 
111 	void __iomem			*base;
112 	int				irq;
113 	spinlock_t			irq_lock;
114 
115 	struct timer_list		cmd_timeout;
116 
117 	unsigned int			slot_id;
118 	struct mmc_host			*mmc;
119 
120 	struct mmc_request		*mrq;
121 	struct mmc_command		*cmd;
122 	int				error;
123 };
124 
125 static void meson_mx_mmc_mask_bits(struct mmc_host *mmc, char reg, u32 mask,
126 				   u32 val)
127 {
128 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
129 	u32 regval;
130 
131 	regval = readl(host->base + reg);
132 	regval &= ~mask;
133 	regval |= (val & mask);
134 
135 	writel(regval, host->base + reg);
136 }
137 
138 static void meson_mx_mmc_soft_reset(struct meson_mx_mmc_host *host)
139 {
140 	writel(MESON_MX_SDIO_IRQC_SOFT_RESET, host->base + MESON_MX_SDIO_IRQC);
141 	udelay(2);
142 }
143 
144 static struct mmc_command *meson_mx_mmc_get_next_cmd(struct mmc_command *cmd)
145 {
146 	if (cmd->opcode == MMC_SET_BLOCK_COUNT && !cmd->error)
147 		return cmd->mrq->cmd;
148 	else if (mmc_op_multi(cmd->opcode) &&
149 		 (!cmd->mrq->sbc || cmd->error || cmd->data->error))
150 		return cmd->mrq->stop;
151 	else
152 		return NULL;
153 }
154 
155 static void meson_mx_mmc_start_cmd(struct mmc_host *mmc,
156 				   struct mmc_command *cmd)
157 {
158 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
159 	unsigned int pack_size;
160 	unsigned long irqflags, timeout;
161 	u32 mult, send = 0, ext = 0;
162 
163 	host->cmd = cmd;
164 
165 	if (cmd->busy_timeout)
166 		timeout = msecs_to_jiffies(cmd->busy_timeout);
167 	else
168 		timeout = msecs_to_jiffies(1000);
169 
170 	switch (mmc_resp_type(cmd)) {
171 	case MMC_RSP_R1:
172 	case MMC_RSP_R1B:
173 	case MMC_RSP_R3:
174 		/* 7 (CMD) + 32 (response) + 7 (CRC) -1 */
175 		send |= FIELD_PREP(MESON_MX_SDIO_SEND_CMD_RESP_BITS_MASK, 45);
176 		break;
177 	case MMC_RSP_R2:
178 		/* 7 (CMD) + 120 (response) + 7 (CRC) -1 */
179 		send |= FIELD_PREP(MESON_MX_SDIO_SEND_CMD_RESP_BITS_MASK, 133);
180 		send |= MESON_MX_SDIO_SEND_RESP_CRC7_FROM_8;
181 		break;
182 	default:
183 		break;
184 	}
185 
186 	if (!(cmd->flags & MMC_RSP_CRC))
187 		send |= MESON_MX_SDIO_SEND_RESP_WITHOUT_CRC7;
188 
189 	if (cmd->flags & MMC_RSP_BUSY)
190 		send |= MESON_MX_SDIO_SEND_CHECK_DAT0_BUSY;
191 
192 	if (cmd->data) {
193 		send |= FIELD_PREP(MESON_MX_SDIO_SEND_REPEAT_PACKAGE_TIMES_MASK,
194 				   (cmd->data->blocks - 1));
195 
196 		pack_size = cmd->data->blksz * BITS_PER_BYTE;
197 		if (mmc->ios.bus_width == MMC_BUS_WIDTH_4)
198 			pack_size += MESON_MX_SDIO_RESPONSE_CRC16_BITS * 4;
199 		else
200 			pack_size += MESON_MX_SDIO_RESPONSE_CRC16_BITS * 1;
201 
202 		ext |= FIELD_PREP(MESON_MX_SDIO_EXT_DATA_RW_NUMBER_MASK,
203 				  pack_size);
204 
205 		if (cmd->data->flags & MMC_DATA_WRITE)
206 			send |= MESON_MX_SDIO_SEND_DATA;
207 		else
208 			send |= MESON_MX_SDIO_SEND_RESP_HAS_DATA;
209 
210 		cmd->data->bytes_xfered = 0;
211 	}
212 
213 	send |= FIELD_PREP(MESON_MX_SDIO_SEND_COMMAND_INDEX_MASK,
214 			   (0x40 | cmd->opcode));
215 
216 	spin_lock_irqsave(&host->irq_lock, irqflags);
217 
218 	mult = readl(host->base + MESON_MX_SDIO_MULT);
219 	mult &= ~MESON_MX_SDIO_MULT_PORT_SEL_MASK;
220 	mult |= FIELD_PREP(MESON_MX_SDIO_MULT_PORT_SEL_MASK, host->slot_id);
221 	mult |= BIT(31);
222 	writel(mult, host->base + MESON_MX_SDIO_MULT);
223 
224 	/* enable the CMD done interrupt */
225 	meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_IRQC,
226 			       MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN,
227 			       MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN);
228 
229 	/* clear pending interrupts */
230 	meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_IRQS,
231 			       MESON_MX_SDIO_IRQS_CMD_INT,
232 			       MESON_MX_SDIO_IRQS_CMD_INT);
233 
234 	writel(cmd->arg, host->base + MESON_MX_SDIO_ARGU);
235 	writel(ext, host->base + MESON_MX_SDIO_EXT);
236 	writel(send, host->base + MESON_MX_SDIO_SEND);
237 
238 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
239 
240 	mod_timer(&host->cmd_timeout, jiffies + timeout);
241 }
242 
243 static void meson_mx_mmc_request_done(struct meson_mx_mmc_host *host)
244 {
245 	struct mmc_request *mrq;
246 
247 	mrq = host->mrq;
248 
249 	host->mrq = NULL;
250 	host->cmd = NULL;
251 
252 	mmc_request_done(host->mmc, mrq);
253 }
254 
255 static void meson_mx_mmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
256 {
257 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
258 	unsigned short vdd = ios->vdd;
259 	unsigned long clk_rate = ios->clock;
260 
261 	switch (ios->bus_width) {
262 	case MMC_BUS_WIDTH_1:
263 		meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_CONF,
264 				       MESON_MX_SDIO_CONF_BUS_WIDTH, 0);
265 		break;
266 
267 	case MMC_BUS_WIDTH_4:
268 		meson_mx_mmc_mask_bits(mmc, MESON_MX_SDIO_CONF,
269 				       MESON_MX_SDIO_CONF_BUS_WIDTH,
270 				       MESON_MX_SDIO_CONF_BUS_WIDTH);
271 		break;
272 
273 	case MMC_BUS_WIDTH_8:
274 	default:
275 		dev_err(mmc_dev(mmc), "unsupported bus width: %d\n",
276 			ios->bus_width);
277 		host->error = -EINVAL;
278 		return;
279 	}
280 
281 	host->error = clk_set_rate(host->cfg_div_clk, ios->clock);
282 	if (host->error) {
283 		dev_warn(mmc_dev(mmc),
284 				"failed to set MMC clock to %lu: %d\n",
285 				clk_rate, host->error);
286 		return;
287 	}
288 
289 	mmc->actual_clock = clk_get_rate(host->cfg_div_clk);
290 
291 	switch (ios->power_mode) {
292 	case MMC_POWER_OFF:
293 		vdd = 0;
294 		/* fall through */
295 	case MMC_POWER_UP:
296 		if (!IS_ERR(mmc->supply.vmmc)) {
297 			host->error = mmc_regulator_set_ocr(mmc,
298 							    mmc->supply.vmmc,
299 							    vdd);
300 			if (host->error)
301 				return;
302 		}
303 		break;
304 	}
305 }
306 
307 static int meson_mx_mmc_map_dma(struct mmc_host *mmc, struct mmc_request *mrq)
308 {
309 	struct mmc_data *data = mrq->data;
310 	int dma_len;
311 	struct scatterlist *sg;
312 
313 	if (!data)
314 		return 0;
315 
316 	sg = data->sg;
317 	if (sg->offset & 3 || sg->length & 3) {
318 		dev_err(mmc_dev(mmc),
319 			"unaligned scatterlist: offset %x length %d\n",
320 			sg->offset, sg->length);
321 		return -EINVAL;
322 	}
323 
324 	dma_len = dma_map_sg(mmc_dev(mmc), data->sg, data->sg_len,
325 			     mmc_get_dma_dir(data));
326 	if (dma_len <= 0) {
327 		dev_err(mmc_dev(mmc), "dma_map_sg failed\n");
328 		return -ENOMEM;
329 	}
330 
331 	return 0;
332 }
333 
334 static void meson_mx_mmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
335 {
336 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
337 	struct mmc_command *cmd = mrq->cmd;
338 
339 	if (!host->error)
340 		host->error = meson_mx_mmc_map_dma(mmc, mrq);
341 
342 	if (host->error) {
343 		cmd->error = host->error;
344 		mmc_request_done(mmc, mrq);
345 		return;
346 	}
347 
348 	host->mrq = mrq;
349 
350 	if (mrq->data)
351 		writel(sg_dma_address(mrq->data->sg),
352 		       host->base + MESON_MX_SDIO_ADDR);
353 
354 	if (mrq->sbc)
355 		meson_mx_mmc_start_cmd(mmc, mrq->sbc);
356 	else
357 		meson_mx_mmc_start_cmd(mmc, mrq->cmd);
358 }
359 
360 static int meson_mx_mmc_card_busy(struct mmc_host *mmc)
361 {
362 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
363 	u32 irqc = readl(host->base + MESON_MX_SDIO_IRQC);
364 
365 	return !!(irqc & MESON_MX_SDIO_IRQC_FORCE_DATA_DAT_MASK);
366 }
367 
368 static void meson_mx_mmc_read_response(struct mmc_host *mmc,
369 				       struct mmc_command *cmd)
370 {
371 	struct meson_mx_mmc_host *host = mmc_priv(mmc);
372 	u32 mult;
373 	int i, resp[4];
374 
375 	mult = readl(host->base + MESON_MX_SDIO_MULT);
376 	mult |= MESON_MX_SDIO_MULT_WR_RD_OUT_INDEX;
377 	mult &= ~MESON_MX_SDIO_MULT_RESP_READ_INDEX_MASK;
378 	mult |= FIELD_PREP(MESON_MX_SDIO_MULT_RESP_READ_INDEX_MASK, 0);
379 	writel(mult, host->base + MESON_MX_SDIO_MULT);
380 
381 	if (cmd->flags & MMC_RSP_136) {
382 		for (i = 0; i <= 3; i++)
383 			resp[3 - i] = readl(host->base + MESON_MX_SDIO_ARGU);
384 		cmd->resp[0] = (resp[0] << 8) | ((resp[1] >> 24) & 0xff);
385 		cmd->resp[1] = (resp[1] << 8) | ((resp[2] >> 24) & 0xff);
386 		cmd->resp[2] = (resp[2] << 8) | ((resp[3] >> 24) & 0xff);
387 		cmd->resp[3] = (resp[3] << 8);
388 	} else if (cmd->flags & MMC_RSP_PRESENT) {
389 		cmd->resp[0] = readl(host->base + MESON_MX_SDIO_ARGU);
390 	}
391 }
392 
393 static irqreturn_t meson_mx_mmc_process_cmd_irq(struct meson_mx_mmc_host *host,
394 						u32 irqs, u32 send)
395 {
396 	struct mmc_command *cmd = host->cmd;
397 
398 	/*
399 	 * NOTE: even though it shouldn't happen we sometimes get command
400 	 * interrupts twice (at least this is what it looks like). Ideally
401 	 * we find out why this happens and warn here as soon as it occurs.
402 	 */
403 	if (!cmd)
404 		return IRQ_HANDLED;
405 
406 	cmd->error = 0;
407 	meson_mx_mmc_read_response(host->mmc, cmd);
408 
409 	if (cmd->data) {
410 		if (!((irqs & MESON_MX_SDIO_IRQS_DATA_READ_CRC16_OK) ||
411 		      (irqs & MESON_MX_SDIO_IRQS_DATA_WRITE_CRC16_OK)))
412 			cmd->error = -EILSEQ;
413 	} else {
414 		if (!((irqs & MESON_MX_SDIO_IRQS_RESP_CRC7_OK) ||
415 		      (send & MESON_MX_SDIO_SEND_RESP_WITHOUT_CRC7)))
416 			cmd->error = -EILSEQ;
417 	}
418 
419 	return IRQ_WAKE_THREAD;
420 }
421 
422 static irqreturn_t meson_mx_mmc_irq(int irq, void *data)
423 {
424 	struct meson_mx_mmc_host *host = (void *) data;
425 	u32 irqs, send;
426 	unsigned long irqflags;
427 	irqreturn_t ret;
428 
429 	spin_lock_irqsave(&host->irq_lock, irqflags);
430 
431 	irqs = readl(host->base + MESON_MX_SDIO_IRQS);
432 	send = readl(host->base + MESON_MX_SDIO_SEND);
433 
434 	if (irqs & MESON_MX_SDIO_IRQS_CMD_INT)
435 		ret = meson_mx_mmc_process_cmd_irq(host, irqs, send);
436 	else
437 		ret = IRQ_HANDLED;
438 
439 	/* finally ACK all pending interrupts */
440 	writel(irqs, host->base + MESON_MX_SDIO_IRQS);
441 
442 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
443 
444 	return ret;
445 }
446 
447 static irqreturn_t meson_mx_mmc_irq_thread(int irq, void *irq_data)
448 {
449 	struct meson_mx_mmc_host *host = (void *) irq_data;
450 	struct mmc_command *cmd = host->cmd, *next_cmd;
451 
452 	if (WARN_ON(!cmd))
453 		return IRQ_HANDLED;
454 
455 	del_timer_sync(&host->cmd_timeout);
456 
457 	if (cmd->data) {
458 		dma_unmap_sg(mmc_dev(host->mmc), cmd->data->sg,
459 				cmd->data->sg_len,
460 				mmc_get_dma_dir(cmd->data));
461 
462 		cmd->data->bytes_xfered = cmd->data->blksz * cmd->data->blocks;
463 	}
464 
465 	next_cmd = meson_mx_mmc_get_next_cmd(cmd);
466 	if (next_cmd)
467 		meson_mx_mmc_start_cmd(host->mmc, next_cmd);
468 	else
469 		meson_mx_mmc_request_done(host);
470 
471 	return IRQ_HANDLED;
472 }
473 
474 static void meson_mx_mmc_timeout(struct timer_list *t)
475 {
476 	struct meson_mx_mmc_host *host = from_timer(host, t, cmd_timeout);
477 	unsigned long irqflags;
478 	u32 irqc;
479 
480 	spin_lock_irqsave(&host->irq_lock, irqflags);
481 
482 	/* disable the CMD interrupt */
483 	irqc = readl(host->base + MESON_MX_SDIO_IRQC);
484 	irqc &= ~MESON_MX_SDIO_IRQC_ARC_CMD_INT_EN;
485 	writel(irqc, host->base + MESON_MX_SDIO_IRQC);
486 
487 	spin_unlock_irqrestore(&host->irq_lock, irqflags);
488 
489 	/*
490 	 * skip the timeout handling if the interrupt handler already processed
491 	 * the command.
492 	 */
493 	if (!host->cmd)
494 		return;
495 
496 	dev_dbg(mmc_dev(host->mmc),
497 		"Timeout on CMD%u (IRQS = 0x%08x, ARGU = 0x%08x)\n",
498 		host->cmd->opcode, readl(host->base + MESON_MX_SDIO_IRQS),
499 		readl(host->base + MESON_MX_SDIO_ARGU));
500 
501 	host->cmd->error = -ETIMEDOUT;
502 
503 	meson_mx_mmc_request_done(host);
504 }
505 
506 static struct mmc_host_ops meson_mx_mmc_ops = {
507 	.request		= meson_mx_mmc_request,
508 	.set_ios		= meson_mx_mmc_set_ios,
509 	.card_busy		= meson_mx_mmc_card_busy,
510 	.get_cd			= mmc_gpio_get_cd,
511 	.get_ro			= mmc_gpio_get_ro,
512 };
513 
514 static struct platform_device *meson_mx_mmc_slot_pdev(struct device *parent)
515 {
516 	struct device_node *slot_node;
517 	struct platform_device *pdev;
518 
519 	/*
520 	 * TODO: the MMC core framework currently does not support
521 	 * controllers with multiple slots properly. So we only register
522 	 * the first slot for now
523 	 */
524 	slot_node = of_get_compatible_child(parent->of_node, "mmc-slot");
525 	if (!slot_node) {
526 		dev_warn(parent, "no 'mmc-slot' sub-node found\n");
527 		return ERR_PTR(-ENOENT);
528 	}
529 
530 	pdev = of_platform_device_create(slot_node, NULL, parent);
531 	of_node_put(slot_node);
532 
533 	return pdev;
534 }
535 
536 static int meson_mx_mmc_add_host(struct meson_mx_mmc_host *host)
537 {
538 	struct mmc_host *mmc = host->mmc;
539 	struct device *slot_dev = mmc_dev(mmc);
540 	int ret;
541 
542 	if (of_property_read_u32(slot_dev->of_node, "reg", &host->slot_id)) {
543 		dev_err(slot_dev, "missing 'reg' property\n");
544 		return -EINVAL;
545 	}
546 
547 	if (host->slot_id >= MESON_MX_SDIO_MAX_SLOTS) {
548 		dev_err(slot_dev, "invalid 'reg' property value %d\n",
549 			host->slot_id);
550 		return -EINVAL;
551 	}
552 
553 	/* Get regulators and the supported OCR mask */
554 	ret = mmc_regulator_get_supply(mmc);
555 	if (ret)
556 		return ret;
557 
558 	mmc->max_req_size = MESON_MX_SDIO_BOUNCE_REQ_SIZE;
559 	mmc->max_seg_size = mmc->max_req_size;
560 	mmc->max_blk_count =
561 		FIELD_GET(MESON_MX_SDIO_SEND_REPEAT_PACKAGE_TIMES_MASK,
562 			  0xffffffff);
563 	mmc->max_blk_size = FIELD_GET(MESON_MX_SDIO_EXT_DATA_RW_NUMBER_MASK,
564 				      0xffffffff);
565 	mmc->max_blk_size -= (4 * MESON_MX_SDIO_RESPONSE_CRC16_BITS);
566 	mmc->max_blk_size /= BITS_PER_BYTE;
567 
568 	/* Get the min and max supported clock rates */
569 	mmc->f_min = clk_round_rate(host->cfg_div_clk, 1);
570 	mmc->f_max = clk_round_rate(host->cfg_div_clk,
571 				    clk_get_rate(host->parent_clk));
572 
573 	mmc->caps |= MMC_CAP_ERASE | MMC_CAP_CMD23;
574 	mmc->ops = &meson_mx_mmc_ops;
575 
576 	ret = mmc_of_parse(mmc);
577 	if (ret)
578 		return ret;
579 
580 	ret = mmc_add_host(mmc);
581 	if (ret)
582 		return ret;
583 
584 	return 0;
585 }
586 
587 static int meson_mx_mmc_register_clks(struct meson_mx_mmc_host *host)
588 {
589 	struct clk_init_data init;
590 	const char *clk_div_parent, *clk_fixed_factor_parent;
591 
592 	clk_fixed_factor_parent = __clk_get_name(host->parent_clk);
593 	init.name = devm_kasprintf(host->controller_dev, GFP_KERNEL,
594 				   "%s#fixed_factor",
595 				   dev_name(host->controller_dev));
596 	if (!init.name)
597 		return -ENOMEM;
598 
599 	init.ops = &clk_fixed_factor_ops;
600 	init.flags = 0;
601 	init.parent_names = &clk_fixed_factor_parent;
602 	init.num_parents = 1;
603 	host->fixed_factor.div = 2;
604 	host->fixed_factor.mult = 1;
605 	host->fixed_factor.hw.init = &init;
606 
607 	host->fixed_factor_clk = devm_clk_register(host->controller_dev,
608 						 &host->fixed_factor.hw);
609 	if (WARN_ON(IS_ERR(host->fixed_factor_clk)))
610 		return PTR_ERR(host->fixed_factor_clk);
611 
612 	clk_div_parent = __clk_get_name(host->fixed_factor_clk);
613 	init.name = devm_kasprintf(host->controller_dev, GFP_KERNEL,
614 				   "%s#div", dev_name(host->controller_dev));
615 	if (!init.name)
616 		return -ENOMEM;
617 
618 	init.ops = &clk_divider_ops;
619 	init.flags = CLK_SET_RATE_PARENT;
620 	init.parent_names = &clk_div_parent;
621 	init.num_parents = 1;
622 	host->cfg_div.reg = host->base + MESON_MX_SDIO_CONF;
623 	host->cfg_div.shift = MESON_MX_SDIO_CONF_CMD_CLK_DIV_SHIFT;
624 	host->cfg_div.width = MESON_MX_SDIO_CONF_CMD_CLK_DIV_WIDTH;
625 	host->cfg_div.hw.init = &init;
626 	host->cfg_div.flags = CLK_DIVIDER_ALLOW_ZERO;
627 
628 	host->cfg_div_clk = devm_clk_register(host->controller_dev,
629 					      &host->cfg_div.hw);
630 	if (WARN_ON(IS_ERR(host->cfg_div_clk)))
631 		return PTR_ERR(host->cfg_div_clk);
632 
633 	return 0;
634 }
635 
636 static int meson_mx_mmc_probe(struct platform_device *pdev)
637 {
638 	struct platform_device *slot_pdev;
639 	struct mmc_host *mmc;
640 	struct meson_mx_mmc_host *host;
641 	struct resource *res;
642 	int ret, irq;
643 	u32 conf;
644 
645 	slot_pdev = meson_mx_mmc_slot_pdev(&pdev->dev);
646 	if (!slot_pdev)
647 		return -ENODEV;
648 	else if (IS_ERR(slot_pdev))
649 		return PTR_ERR(slot_pdev);
650 
651 	mmc = mmc_alloc_host(sizeof(*host), &slot_pdev->dev);
652 	if (!mmc) {
653 		ret = -ENOMEM;
654 		goto error_unregister_slot_pdev;
655 	}
656 
657 	host = mmc_priv(mmc);
658 	host->mmc = mmc;
659 	host->controller_dev = &pdev->dev;
660 
661 	spin_lock_init(&host->irq_lock);
662 	timer_setup(&host->cmd_timeout, meson_mx_mmc_timeout, 0);
663 
664 	platform_set_drvdata(pdev, host);
665 
666 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
667 	host->base = devm_ioremap_resource(host->controller_dev, res);
668 	if (IS_ERR(host->base)) {
669 		ret = PTR_ERR(host->base);
670 		goto error_free_mmc;
671 	}
672 
673 	irq = platform_get_irq(pdev, 0);
674 	ret = devm_request_threaded_irq(host->controller_dev, irq,
675 					meson_mx_mmc_irq,
676 					meson_mx_mmc_irq_thread, IRQF_ONESHOT,
677 					NULL, host);
678 	if (ret)
679 		goto error_free_mmc;
680 
681 	host->core_clk = devm_clk_get(host->controller_dev, "core");
682 	if (IS_ERR(host->core_clk)) {
683 		ret = PTR_ERR(host->core_clk);
684 		goto error_free_mmc;
685 	}
686 
687 	host->parent_clk = devm_clk_get(host->controller_dev, "clkin");
688 	if (IS_ERR(host->parent_clk)) {
689 		ret = PTR_ERR(host->parent_clk);
690 		goto error_free_mmc;
691 	}
692 
693 	ret = meson_mx_mmc_register_clks(host);
694 	if (ret)
695 		goto error_free_mmc;
696 
697 	ret = clk_prepare_enable(host->core_clk);
698 	if (ret) {
699 		dev_err(host->controller_dev, "Failed to enable core clock\n");
700 		goto error_free_mmc;
701 	}
702 
703 	ret = clk_prepare_enable(host->cfg_div_clk);
704 	if (ret) {
705 		dev_err(host->controller_dev, "Failed to enable MMC clock\n");
706 		goto error_disable_core_clk;
707 	}
708 
709 	conf = 0;
710 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_CMD_ARGUMENT_BITS_MASK, 39);
711 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_M_ENDIAN_MASK, 0x3);
712 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_WRITE_NWR_MASK, 0x2);
713 	conf |= FIELD_PREP(MESON_MX_SDIO_CONF_WRITE_CRC_OK_STATUS_MASK, 0x2);
714 	writel(conf, host->base + MESON_MX_SDIO_CONF);
715 
716 	meson_mx_mmc_soft_reset(host);
717 
718 	ret = meson_mx_mmc_add_host(host);
719 	if (ret)
720 		goto error_disable_clks;
721 
722 	return 0;
723 
724 error_disable_clks:
725 	clk_disable_unprepare(host->cfg_div_clk);
726 error_disable_core_clk:
727 	clk_disable_unprepare(host->core_clk);
728 error_free_mmc:
729 	mmc_free_host(mmc);
730 error_unregister_slot_pdev:
731 	of_platform_device_destroy(&slot_pdev->dev, NULL);
732 	return ret;
733 }
734 
735 static int meson_mx_mmc_remove(struct platform_device *pdev)
736 {
737 	struct meson_mx_mmc_host *host = platform_get_drvdata(pdev);
738 	struct device *slot_dev = mmc_dev(host->mmc);
739 
740 	del_timer_sync(&host->cmd_timeout);
741 
742 	mmc_remove_host(host->mmc);
743 
744 	of_platform_device_destroy(slot_dev, NULL);
745 
746 	clk_disable_unprepare(host->cfg_div_clk);
747 	clk_disable_unprepare(host->core_clk);
748 
749 	mmc_free_host(host->mmc);
750 
751 	return 0;
752 }
753 
754 static const struct of_device_id meson_mx_mmc_of_match[] = {
755 	{ .compatible = "amlogic,meson8-sdio", },
756 	{ .compatible = "amlogic,meson8b-sdio", },
757 	{ /* sentinel */ }
758 };
759 MODULE_DEVICE_TABLE(of, meson_mx_mmc_of_match);
760 
761 static struct platform_driver meson_mx_mmc_driver = {
762 	.probe   = meson_mx_mmc_probe,
763 	.remove  = meson_mx_mmc_remove,
764 	.driver  = {
765 		.name = "meson-mx-sdio",
766 		.of_match_table = of_match_ptr(meson_mx_mmc_of_match),
767 	},
768 };
769 
770 module_platform_driver(meson_mx_mmc_driver);
771 
772 MODULE_DESCRIPTION("Meson6, Meson8 and Meson8b SDIO/MMC Host Driver");
773 MODULE_AUTHOR("Carlo Caione <carlo@endlessm.com>");
774 MODULE_AUTHOR("Martin Blumenstingl <martin.blumenstingl@googlemail.com>");
775 MODULE_LICENSE("GPL v2");
776