xref: /linux/drivers/mmc/host/sunplus-mmc.c (revision 24168c5e6dfbdd5b414f048f47f75d64533296ca)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (c) Sunplus Inc.
4  * Author: Tony Huang <tonyhuang.sunplus@gmail.com>
5  * Author: Li-hao Kuo <lhjeff911@gmail.com>
6  */
7 
8 #include <linux/bitfield.h>
9 #include <linux/clk.h>
10 #include <linux/delay.h>
11 #include <linux/dma-mapping.h>
12 #include <linux/interrupt.h>
13 #include <linux/iopoll.h>
14 #include <linux/mmc/core.h>
15 #include <linux/mmc/host.h>
16 #include <linux/mmc/mmc.h>
17 #include <linux/mmc/sdio.h>
18 #include <linux/mmc/slot-gpio.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm.h>
23 #include <linux/pm_runtime.h>
24 #include <linux/reset.h>
25 
26 #define SPMMC_MIN_CLK			400000
27 #define SPMMC_MAX_CLK			52000000
28 #define SPMMC_MAX_BLK_COUNT		65536
29 #define SPMMC_MAX_TUNABLE_DLY	7
30 #define SPMMC_TIMEOUT_US		500000
31 #define SPMMC_POLL_DELAY_US		10
32 
33 #define SPMMC_CARD_MEDIATYPE_SRCDST_REG 0x0000
34 #define SPMMC_MEDIA_TYPE		GENMASK(2, 0)
35 #define SPMMC_DMA_SOURCE		GENMASK(6, 4)
36 #define SPMMC_DMA_DESTINATION		GENMASK(10, 8)
37 #define SPMMC_MEDIA_NONE	0
38 #define SPMMC_MEDIA_SD		6
39 #define SPMMC_MEDIA_MS		7
40 
41 #define SPMMC_SDRAM_SECTOR_0_SIZE_REG	0x0008
42 #define SPMMC_DMA_BASE_ADDR_REG		0x000C
43 #define SPMMC_HW_DMA_CTRL_REG		0x0010
44 #define SPMMC_HW_DMA_RST	BIT(9)
45 #define SPMMC_DMAIDLE		BIT(10)
46 
47 #define SPMMC_MAX_DMA_MEMORY_SECTORS	8
48 
49 #define SPMMC_SDRAM_SECTOR_1_ADDR_REG 0x0018
50 #define SPMMC_SDRAM_SECTOR_1_LENG_REG 0x001C
51 #define SPMMC_SDRAM_SECTOR_2_ADDR_REG 0x0020
52 #define SPMMC_SDRAM_SECTOR_2_LENG_REG 0x0024
53 #define SPMMC_SDRAM_SECTOR_3_ADDR_REG 0x0028
54 #define SPMMC_SDRAM_SECTOR_3_LENG_REG 0x002C
55 #define SPMMC_SDRAM_SECTOR_4_ADDR_REG 0x0030
56 #define SPMMC_SDRAM_SECTOR_4_LENG_REG 0x0034
57 #define SPMMC_SDRAM_SECTOR_5_ADDR_REG 0x0038
58 #define SPMMC_SDRAM_SECTOR_5_LENG_REG 0x003C
59 #define SPMMC_SDRAM_SECTOR_6_ADDR_REG 0x0040
60 #define SPMMC_SDRAM_SECTOR_6_LENG_REG 0x0044
61 #define SPMMC_SDRAM_SECTOR_7_ADDR_REG 0x0048
62 #define SPMMC_SDRAM_SECTOR_7_LENG_REG 0x004C
63 
64 #define SPMMC_SD_INT_REG	0x0088
65 #define SPMMC_SDINT_SDCMPEN	BIT(0)
66 #define SPMMC_SDINT_SDCMP	BIT(1)
67 #define SPMMC_SDINT_SDCMPCLR	BIT(2)
68 #define SPMMC_SDINT_SDIOEN	BIT(3)
69 #define SPMMC_SDINT_SDIO	BIT(4)
70 #define SPMMC_SDINT_SDIOCLR	BIT(5)
71 
72 #define SPMMC_SD_PAGE_NUM_REG	0x008C
73 
74 #define SPMMC_SD_CONFIG0_REG	0x0090
75 #define SPMMC_SD_PIO_MODE	BIT(0)
76 #define SPMMC_SD_DDR_MODE	BIT(1)
77 #define SPMMC_SD_LEN_MODE	BIT(2)
78 #define SPMMC_SD_TRANS_MODE	GENMASK(5, 4)
79 #define SPMMC_SD_AUTO_RESPONSE	BIT(6)
80 #define SPMMC_SD_CMD_DUMMY	BIT(7)
81 #define SPMMC_SD_RSP_CHK_EN	BIT(8)
82 #define SPMMC_SDIO_MODE		BIT(9)
83 #define SPMMC_SD_MMC_MODE	BIT(10)
84 #define SPMMC_SD_DATA_WD	BIT(11)
85 #define SPMMC_RX4_EN		BIT(14)
86 #define SPMMC_SD_RSP_TYPE	BIT(15)
87 #define SPMMC_MMC8_EN		BIT(18)
88 #define SPMMC_CLOCK_DIVISION	GENMASK(31, 20)
89 
90 #define SPMMC_SDIO_CTRL_REG		0x0094
91 #define SPMMC_INT_MULTI_TRIG		BIT(6)
92 
93 #define SPMMC_SD_RST_REG		0x0098
94 #define SPMMC_SD_CTRL_REG		0x009C
95 #define SPMMC_NEW_COMMAND_TRIGGER	BIT(0)
96 #define SPMMC_DUMMY_CLOCK_TRIGGER	BIT(1)
97 
98 #define SPMMC_SD_STATUS_REG						0x00A0
99 #define SPMMC_SDSTATUS_DUMMY_READY				BIT(0)
100 #define SPMMC_SDSTATUS_RSP_BUF_FULL				BIT(1)
101 #define SPMMC_SDSTATUS_TX_DATA_BUF_EMPTY		BIT(2)
102 #define SPMMC_SDSTATUS_RX_DATA_BUF_FULL			BIT(3)
103 #define SPMMC_SDSTATUS_CMD_PIN_STATUS			BIT(4)
104 #define SPMMC_SDSTATUS_DAT0_PIN_STATUS			BIT(5)
105 #define SPMMC_SDSTATUS_RSP_TIMEOUT				BIT(6)
106 #define SPMMC_SDSTATUS_CARD_CRC_CHECK_TIMEOUT	BIT(7)
107 #define SPMMC_SDSTATUS_STB_TIMEOUT				BIT(8)
108 #define SPMMC_SDSTATUS_RSP_CRC7_ERROR			BIT(9)
109 #define SPMMC_SDSTATUS_CRC_TOKEN_CHECK_ERROR	BIT(10)
110 #define SPMMC_SDSTATUS_RDATA_CRC16_ERROR		BIT(11)
111 #define SPMMC_SDSTATUS_SUSPEND_STATE_READY		BIT(12)
112 #define SPMMC_SDSTATUS_BUSY_CYCLE				BIT(13)
113 #define SPMMC_SDSTATUS_DAT1_PIN_STATUS			BIT(14)
114 #define SPMMC_SDSTATUS_SD_SENSE_STATUS			BIT(15)
115 #define SPMMC_SDSTATUS_BOOT_ACK_TIMEOUT			BIT(16)
116 #define SPMMC_SDSTATUS_BOOT_DATA_TIMEOUT		BIT(17)
117 #define SPMMC_SDSTATUS_BOOT_ACK_ERROR			BIT(18)
118 
119 #define SPMMC_SD_STATE_REG		0x00A4
120 #define SPMMC_CRCTOKEN_CHECK_RESULT	GENMASK(6, 4)
121 #define SPMMC_SDSTATE_ERROR		BIT(13)
122 #define SPMMC_SDSTATE_FINISH	BIT(14)
123 
124 #define SPMMC_SD_HW_STATE_REG		0x00A8
125 #define SPMMC_SD_BLOCKSIZE_REG		0x00AC
126 
127 #define SPMMC_SD_CONFIG1_REG		0x00B0
128 #define SPMMC_TX_DUMMY_NUM		GENMASK(8, 0)
129 #define SPMMC_SD_HIGH_SPEED_EN		BIT(31)
130 
131 #define SPMMC_SD_TIMING_CONFIG0_REG 0x00B4
132 #define SPMMC_SD_CLOCK_DELAY	GENMASK(2, 0)
133 #define SPMMC_SD_WRITE_DATA_DELAY	GENMASK(6, 4)
134 #define SPMMC_SD_WRITE_COMMAND_DELAY	GENMASK(10, 8)
135 #define SPMMC_SD_READ_RESPONSE_DELAY	GENMASK(14, 12)
136 #define SPMMC_SD_READ_DATA_DELAY	GENMASK(18, 16)
137 #define SPMMC_SD_READ_CRC_DELAY	GENMASK(22, 20)
138 
139 #define SPMMC_SD_PIODATATX_REG		0x00BC
140 #define SPMMC_SD_PIODATARX_REG		0x00C0
141 #define SPMMC_SD_CMDBUF0_3_REG		0x00C4
142 #define SPMMC_SD_CMDBUF4_REG		0x00C8
143 #define SPMMC_SD_RSPBUF0_3_REG		0x00CC
144 #define SPMMC_SD_RSPBUF4_5_REG		0x00D0
145 
146 #define SPMMC_MAX_RETRIES (8 * 8)
147 
148 struct spmmc_tuning_info {
149 	int enable_tuning;
150 	int need_tuning;
151 	int retried; /* how many times has been retried */
152 	u32 rd_crc_dly:3;
153 	u32 rd_dat_dly:3;
154 	u32 rd_rsp_dly:3;
155 	u32 wr_cmd_dly:3;
156 	u32 wr_dat_dly:3;
157 	u32 clk_dly:3;
158 };
159 
160 #define SPMMC_DMA_MODE 0
161 #define	SPMMC_PIO_MODE 1
162 
163 struct spmmc_host {
164 	void __iomem *base;
165 	struct clk *clk;
166 	struct reset_control *rstc;
167 	struct mmc_host *mmc;
168 	struct mmc_request *mrq; /* current mrq */
169 	int irq;
170 	int dmapio_mode;
171 	struct spmmc_tuning_info tuning_info;
172 	int dma_int_threshold;
173 	int dma_use_int;
174 };
175 
176 static inline int spmmc_wait_finish(struct spmmc_host *host)
177 {
178 	u32 state;
179 
180 	return readl_poll_timeout(host->base + SPMMC_SD_STATE_REG, state,
181 					(state & SPMMC_SDSTATE_FINISH),
182 					SPMMC_POLL_DELAY_US, SPMMC_TIMEOUT_US);
183 }
184 
185 static inline int spmmc_wait_sdstatus(struct spmmc_host *host, unsigned int status_bit)
186 {
187 	u32 status;
188 
189 	return readl_poll_timeout(host->base + SPMMC_SD_STATUS_REG, status,
190 					(status & status_bit),
191 					SPMMC_POLL_DELAY_US, SPMMC_TIMEOUT_US);
192 }
193 
194 #define spmmc_wait_rspbuf_full(host) spmmc_wait_sdstatus(host, SPMMC_SDSTATUS_RSP_BUF_FULL)
195 #define spmmc_wait_rxbuf_full(host) spmmc_wait_sdstatus(host, SPMMC_SDSTATUS_RX_DATA_BUF_FULL)
196 #define spmmc_wait_txbuf_empty(host) spmmc_wait_sdstatus(host, SPMMC_SDSTATUS_TX_DATA_BUF_EMPTY)
197 
198 static void spmmc_get_rsp(struct spmmc_host *host, struct mmc_command *cmd)
199 {
200 	u32 value0_3, value4_5;
201 
202 	if (!(cmd->flags & MMC_RSP_PRESENT))
203 		return;
204 	if (cmd->flags & MMC_RSP_136) {
205 		if (spmmc_wait_rspbuf_full(host))
206 			return;
207 		value0_3 = readl(host->base + SPMMC_SD_RSPBUF0_3_REG);
208 		value4_5 = readl(host->base + SPMMC_SD_RSPBUF4_5_REG) & 0xffff;
209 		cmd->resp[0] = (value0_3 << 8) | (value4_5 >> 8);
210 		cmd->resp[1] = value4_5 << 24;
211 		value0_3 = readl(host->base + SPMMC_SD_RSPBUF0_3_REG);
212 		value4_5 = readl(host->base + SPMMC_SD_RSPBUF4_5_REG) & 0xffff;
213 		cmd->resp[1] |= value0_3 >> 8;
214 		cmd->resp[2] = value0_3 << 24;
215 		cmd->resp[2] |= value4_5 << 8;
216 		value0_3 = readl(host->base + SPMMC_SD_RSPBUF0_3_REG);
217 		value4_5 = readl(host->base + SPMMC_SD_RSPBUF4_5_REG) & 0xffff;
218 		cmd->resp[2] |= value0_3 >> 24;
219 		cmd->resp[3] = value0_3 << 8;
220 		cmd->resp[3] |= value4_5 >> 8;
221 	} else {
222 		if (spmmc_wait_rspbuf_full(host))
223 			return;
224 		value0_3 = readl(host->base + SPMMC_SD_RSPBUF0_3_REG);
225 		value4_5 = readl(host->base + SPMMC_SD_RSPBUF4_5_REG) & 0xffff;
226 		cmd->resp[0] = (value0_3 << 8) | (value4_5 >> 8);
227 		cmd->resp[1] = value4_5 << 24;
228 	}
229 }
230 
231 static void spmmc_set_bus_clk(struct spmmc_host *host, int clk)
232 {
233 	unsigned int clkdiv;
234 	int f_min = host->mmc->f_min;
235 	int f_max = host->mmc->f_max;
236 	u32 value = readl(host->base + SPMMC_SD_CONFIG0_REG);
237 
238 	if (clk < f_min)
239 		clk = f_min;
240 	if (clk > f_max)
241 		clk = f_max;
242 
243 	clkdiv = (clk_get_rate(host->clk) + clk) / clk - 1;
244 	if (clkdiv > 0xfff)
245 		clkdiv = 0xfff;
246 	value &= ~SPMMC_CLOCK_DIVISION;
247 	value |= FIELD_PREP(SPMMC_CLOCK_DIVISION, clkdiv);
248 	writel(value, host->base + SPMMC_SD_CONFIG0_REG);
249 }
250 
251 static void spmmc_set_bus_timing(struct spmmc_host *host, unsigned int timing)
252 {
253 	u32 value = readl(host->base + SPMMC_SD_CONFIG1_REG);
254 	int clkdiv = FIELD_GET(SPMMC_CLOCK_DIVISION, readl(host->base + SPMMC_SD_CONFIG0_REG));
255 	int delay = clkdiv / 2 < 7 ? clkdiv / 2 : 7;
256 	int hs_en = 1, ddr_enabled = 0;
257 
258 	switch (timing) {
259 	case MMC_TIMING_LEGACY:
260 		hs_en = 0;
261 		break;
262 	case MMC_TIMING_MMC_HS:
263 	case MMC_TIMING_SD_HS:
264 	case MMC_TIMING_UHS_SDR50:
265 	case MMC_TIMING_UHS_SDR104:
266 	case MMC_TIMING_MMC_HS200:
267 		hs_en = 1;
268 		break;
269 	case MMC_TIMING_UHS_DDR50:
270 		ddr_enabled = 1;
271 		break;
272 	case MMC_TIMING_MMC_DDR52:
273 		ddr_enabled = 1;
274 		break;
275 	default:
276 		hs_en = 0;
277 		break;
278 	}
279 
280 	if (hs_en) {
281 		value |= SPMMC_SD_HIGH_SPEED_EN;
282 		writel(value, host->base + SPMMC_SD_CONFIG1_REG);
283 		value = readl(host->base + SPMMC_SD_TIMING_CONFIG0_REG);
284 		value &= ~SPMMC_SD_WRITE_DATA_DELAY;
285 		value |= FIELD_PREP(SPMMC_SD_WRITE_DATA_DELAY, delay);
286 		value &= ~SPMMC_SD_WRITE_COMMAND_DELAY;
287 		value |= FIELD_PREP(SPMMC_SD_WRITE_COMMAND_DELAY, delay);
288 		writel(value, host->base + SPMMC_SD_TIMING_CONFIG0_REG);
289 	} else {
290 		value &= ~SPMMC_SD_HIGH_SPEED_EN;
291 		writel(value, host->base + SPMMC_SD_CONFIG1_REG);
292 	}
293 	if (ddr_enabled) {
294 		value = readl(host->base + SPMMC_SD_CONFIG0_REG);
295 		value |= SPMMC_SD_DDR_MODE;
296 		writel(value, host->base + SPMMC_SD_CONFIG0_REG);
297 	} else {
298 		value = readl(host->base + SPMMC_SD_CONFIG0_REG);
299 		value &= ~SPMMC_SD_DDR_MODE;
300 		writel(value, host->base + SPMMC_SD_CONFIG0_REG);
301 	}
302 }
303 
304 static void spmmc_set_bus_width(struct spmmc_host *host, int width)
305 {
306 	u32 value = readl(host->base + SPMMC_SD_CONFIG0_REG);
307 
308 	switch (width) {
309 	case MMC_BUS_WIDTH_8:
310 		value &= ~SPMMC_SD_DATA_WD;
311 		value |= SPMMC_MMC8_EN;
312 		break;
313 	case MMC_BUS_WIDTH_4:
314 		value |= SPMMC_SD_DATA_WD;
315 		value &= ~SPMMC_MMC8_EN;
316 		break;
317 	default:
318 		value &= ~SPMMC_SD_DATA_WD;
319 		value &= ~SPMMC_MMC8_EN;
320 		break;
321 	}
322 	writel(value, host->base + SPMMC_SD_CONFIG0_REG);
323 }
324 
325 /*
326  * select the working mode of controller: sd/sdio/emmc
327  */
328 static void spmmc_set_sdmmc_mode(struct spmmc_host *host)
329 {
330 	u32 value = readl(host->base + SPMMC_SD_CONFIG0_REG);
331 
332 	value |= SPMMC_SD_MMC_MODE;
333 	value &= ~SPMMC_SDIO_MODE;
334 	writel(value, host->base + SPMMC_SD_CONFIG0_REG);
335 }
336 
337 static void spmmc_sw_reset(struct spmmc_host *host)
338 {
339 	u32 value;
340 
341 	/*
342 	 * Must reset dma operation first, or it will
343 	 * be stuck on sd_state == 0x1c00 because of
344 	 * a controller software reset bug
345 	 */
346 	value = readl(host->base + SPMMC_HW_DMA_CTRL_REG);
347 	value |= SPMMC_DMAIDLE;
348 	writel(value, host->base + SPMMC_HW_DMA_CTRL_REG);
349 	value &= ~SPMMC_DMAIDLE;
350 	writel(value, host->base + SPMMC_HW_DMA_CTRL_REG);
351 	value = readl(host->base + SPMMC_HW_DMA_CTRL_REG);
352 	value |= SPMMC_HW_DMA_RST;
353 	writel(value, host->base + SPMMC_HW_DMA_CTRL_REG);
354 	writel(0x7, host->base + SPMMC_SD_RST_REG);
355 	readl_poll_timeout_atomic(host->base + SPMMC_SD_HW_STATE_REG, value,
356 				  !(value & BIT(6)), 1, SPMMC_TIMEOUT_US);
357 }
358 
359 static void spmmc_prepare_cmd(struct spmmc_host *host, struct mmc_command *cmd)
360 {
361 	u32 value;
362 
363 	/* add start bit, according to spec, command format */
364 	value = ((cmd->opcode | 0x40) << 24) | (cmd->arg >> 8);
365 	writel(value, host->base + SPMMC_SD_CMDBUF0_3_REG);
366 	writeb(cmd->arg & 0xff, host->base + SPMMC_SD_CMDBUF4_REG);
367 
368 	/* disable interrupt if needed */
369 	value = readl(host->base + SPMMC_SD_INT_REG);
370 	value |= SPMMC_SDINT_SDCMPCLR;
371 	value &= ~SPMMC_SDINT_SDCMPEN;
372 	writel(value, host->base + SPMMC_SD_INT_REG);
373 
374 	value = readl(host->base + SPMMC_SD_CONFIG0_REG);
375 	value &= ~SPMMC_SD_TRANS_MODE;
376 	value |= SPMMC_SD_CMD_DUMMY;
377 	if (cmd->flags & MMC_RSP_PRESENT) {
378 		value |= SPMMC_SD_AUTO_RESPONSE;
379 	} else {
380 		value &= ~SPMMC_SD_AUTO_RESPONSE;
381 		writel(value, host->base + SPMMC_SD_CONFIG0_REG);
382 
383 		return;
384 	}
385 	/*
386 	 * Currently, host is not capable of checking R2's CRC7,
387 	 * thus, enable crc7 check only for 48 bit response commands
388 	 */
389 	if (cmd->flags & MMC_RSP_CRC && !(cmd->flags & MMC_RSP_136))
390 		value |= SPMMC_SD_RSP_CHK_EN;
391 	else
392 		value &= ~SPMMC_SD_RSP_CHK_EN;
393 
394 	if (cmd->flags & MMC_RSP_136)
395 		value |= SPMMC_SD_RSP_TYPE;
396 	else
397 		value &= ~SPMMC_SD_RSP_TYPE;
398 	writel(value, host->base + SPMMC_SD_CONFIG0_REG);
399 }
400 
401 static void spmmc_prepare_data(struct spmmc_host *host, struct mmc_data *data)
402 {
403 	u32 value, srcdst;
404 
405 	writel(data->blocks - 1, host->base + SPMMC_SD_PAGE_NUM_REG);
406 	writel(data->blksz - 1, host->base + SPMMC_SD_BLOCKSIZE_REG);
407 	value = readl(host->base + SPMMC_SD_CONFIG0_REG);
408 	if (data->flags & MMC_DATA_READ) {
409 		value &= ~SPMMC_SD_TRANS_MODE;
410 		value |= FIELD_PREP(SPMMC_SD_TRANS_MODE, 2);
411 		value &= ~SPMMC_SD_AUTO_RESPONSE;
412 		value &= ~SPMMC_SD_CMD_DUMMY;
413 		srcdst = readl(host->base + SPMMC_CARD_MEDIATYPE_SRCDST_REG);
414 		srcdst &= ~SPMMC_DMA_SOURCE;
415 		srcdst |= FIELD_PREP(SPMMC_DMA_SOURCE, 0x2);
416 		srcdst &= ~SPMMC_DMA_DESTINATION;
417 		srcdst |= FIELD_PREP(SPMMC_DMA_DESTINATION, 0x1);
418 		writel(srcdst, host->base + SPMMC_CARD_MEDIATYPE_SRCDST_REG);
419 	} else {
420 		value &= ~SPMMC_SD_TRANS_MODE;
421 		value |= FIELD_PREP(SPMMC_SD_TRANS_MODE, 1);
422 		srcdst = readl(host->base + SPMMC_CARD_MEDIATYPE_SRCDST_REG);
423 		srcdst &= ~SPMMC_DMA_SOURCE;
424 		srcdst |= FIELD_PREP(SPMMC_DMA_SOURCE, 0x1);
425 		srcdst &= ~SPMMC_DMA_DESTINATION;
426 		srcdst |= FIELD_PREP(SPMMC_DMA_DESTINATION, 0x2);
427 		writel(srcdst, host->base + SPMMC_CARD_MEDIATYPE_SRCDST_REG);
428 	}
429 
430 	value |= SPMMC_SD_LEN_MODE;
431 	if (host->dmapio_mode == SPMMC_DMA_MODE) {
432 		struct scatterlist *sg;
433 		dma_addr_t dma_addr;
434 		unsigned int dma_size;
435 		int i, count = 1;
436 
437 		count = dma_map_sg(host->mmc->parent, data->sg, data->sg_len,
438 				   mmc_get_dma_dir(data));
439 		if (!count || count > SPMMC_MAX_DMA_MEMORY_SECTORS) {
440 			data->error = -EINVAL;
441 
442 			return;
443 		}
444 		for_each_sg(data->sg, sg, count, i) {
445 			dma_addr = sg_dma_address(sg);
446 			dma_size = sg_dma_len(sg) / data->blksz - 1;
447 			if (i == 0) {
448 				writel(dma_addr, host->base + SPMMC_DMA_BASE_ADDR_REG);
449 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_0_SIZE_REG);
450 			} else if (i == 1) {
451 				writel(dma_addr, host->base + SPMMC_SDRAM_SECTOR_1_ADDR_REG);
452 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_1_LENG_REG);
453 			} else if (i == 2) {
454 				writel(dma_addr, host->base + SPMMC_SDRAM_SECTOR_2_ADDR_REG);
455 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_2_LENG_REG);
456 			} else if (i == 3) {
457 				writel(dma_addr, host->base + SPMMC_SDRAM_SECTOR_3_ADDR_REG);
458 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_3_LENG_REG);
459 			} else if (i == 4) {
460 				writel(dma_addr, host->base + SPMMC_SDRAM_SECTOR_4_ADDR_REG);
461 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_4_LENG_REG);
462 			} else if (i == 5) {
463 				writel(dma_addr, host->base + SPMMC_SDRAM_SECTOR_5_ADDR_REG);
464 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_5_LENG_REG);
465 			} else if (i == 6) {
466 				writel(dma_addr, host->base + SPMMC_SDRAM_SECTOR_6_ADDR_REG);
467 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_6_LENG_REG);
468 			} else if (i == 7) {
469 				writel(dma_addr, host->base + SPMMC_SDRAM_SECTOR_7_ADDR_REG);
470 				writel(dma_size, host->base + SPMMC_SDRAM_SECTOR_7_LENG_REG);
471 			}
472 		}
473 		value &= ~SPMMC_SD_PIO_MODE;
474 		writel(value, host->base + SPMMC_SD_CONFIG0_REG);
475 		/* enable interrupt if needed */
476 		if (data->blksz * data->blocks > host->dma_int_threshold) {
477 			host->dma_use_int = 1;
478 			value = readl(host->base + SPMMC_SD_INT_REG);
479 			value &= ~SPMMC_SDINT_SDCMPEN;
480 			value |= FIELD_PREP(SPMMC_SDINT_SDCMPEN, 1); /* sdcmpen */
481 			writel(value, host->base + SPMMC_SD_INT_REG);
482 		}
483 	} else {
484 		value |= SPMMC_SD_PIO_MODE;
485 		value |= SPMMC_RX4_EN;
486 		writel(value, host->base + SPMMC_SD_CONFIG0_REG);
487 	}
488 }
489 
490 static inline void spmmc_trigger_transaction(struct spmmc_host *host)
491 {
492 	u32 value = readl(host->base + SPMMC_SD_CTRL_REG);
493 
494 	value |= SPMMC_NEW_COMMAND_TRIGGER;
495 	writel(value, host->base + SPMMC_SD_CTRL_REG);
496 }
497 
498 static void spmmc_send_stop_cmd(struct spmmc_host *host)
499 {
500 	struct mmc_command stop = {};
501 	u32 value;
502 
503 	stop.opcode = MMC_STOP_TRANSMISSION;
504 	stop.arg = 0;
505 	stop.flags = MMC_RSP_R1B;
506 	spmmc_prepare_cmd(host, &stop);
507 	value = readl(host->base + SPMMC_SD_INT_REG);
508 	value &= ~SPMMC_SDINT_SDCMPEN;
509 	value |= FIELD_PREP(SPMMC_SDINT_SDCMPEN, 0);
510 	writel(value, host->base + SPMMC_SD_INT_REG);
511 	spmmc_trigger_transaction(host);
512 	readl_poll_timeout(host->base + SPMMC_SD_STATE_REG, value,
513 			   (value & SPMMC_SDSTATE_FINISH), 1, SPMMC_TIMEOUT_US);
514 }
515 
516 static int spmmc_check_error(struct spmmc_host *host, struct mmc_request *mrq)
517 {
518 	int ret = 0;
519 	struct mmc_command *cmd = mrq->cmd;
520 	struct mmc_data *data = mrq->data;
521 
522 	u32 value = readl(host->base + SPMMC_SD_STATE_REG);
523 	u32 crc_token = FIELD_GET(SPMMC_CRCTOKEN_CHECK_RESULT, value);
524 
525 	if (value & SPMMC_SDSTATE_ERROR) {
526 		u32 timing_cfg0 = 0;
527 
528 		value = readl(host->base + SPMMC_SD_STATUS_REG);
529 
530 		if (host->tuning_info.enable_tuning) {
531 			timing_cfg0 = readl(host->base + SPMMC_SD_TIMING_CONFIG0_REG);
532 			host->tuning_info.rd_crc_dly = FIELD_GET(SPMMC_SD_READ_CRC_DELAY,
533 								 timing_cfg0);
534 			host->tuning_info.rd_dat_dly = FIELD_GET(SPMMC_SD_READ_DATA_DELAY,
535 								 timing_cfg0);
536 			host->tuning_info.rd_rsp_dly = FIELD_GET(SPMMC_SD_READ_RESPONSE_DELAY,
537 								 timing_cfg0);
538 			host->tuning_info.wr_cmd_dly = FIELD_GET(SPMMC_SD_WRITE_COMMAND_DELAY,
539 								 timing_cfg0);
540 			host->tuning_info.wr_dat_dly = FIELD_GET(SPMMC_SD_WRITE_DATA_DELAY,
541 								 timing_cfg0);
542 		}
543 
544 		if (value & SPMMC_SDSTATUS_RSP_TIMEOUT) {
545 			ret = -ETIMEDOUT;
546 			host->tuning_info.wr_cmd_dly++;
547 		} else if (value & SPMMC_SDSTATUS_RSP_CRC7_ERROR) {
548 			ret = -EILSEQ;
549 			host->tuning_info.rd_rsp_dly++;
550 		} else if (data) {
551 			if ((value & SPMMC_SDSTATUS_STB_TIMEOUT)) {
552 				ret = -ETIMEDOUT;
553 				host->tuning_info.rd_dat_dly++;
554 			} else if (value & SPMMC_SDSTATUS_RDATA_CRC16_ERROR) {
555 				ret = -EILSEQ;
556 				host->tuning_info.rd_dat_dly++;
557 			} else if (value & SPMMC_SDSTATUS_CARD_CRC_CHECK_TIMEOUT) {
558 				ret = -ETIMEDOUT;
559 				host->tuning_info.rd_crc_dly++;
560 			} else if (value & SPMMC_SDSTATUS_CRC_TOKEN_CHECK_ERROR) {
561 				ret = -EILSEQ;
562 				if (crc_token == 0x5)
563 					host->tuning_info.wr_dat_dly++;
564 				else
565 					host->tuning_info.rd_crc_dly++;
566 			}
567 		}
568 		cmd->error = ret;
569 		if (data) {
570 			data->error = ret;
571 			data->bytes_xfered = 0;
572 		}
573 		if (!host->tuning_info.need_tuning && host->tuning_info.enable_tuning)
574 			cmd->retries = SPMMC_MAX_RETRIES;
575 		spmmc_sw_reset(host);
576 
577 		if (host->tuning_info.enable_tuning) {
578 			timing_cfg0 &= ~SPMMC_SD_READ_CRC_DELAY;
579 			timing_cfg0 |= FIELD_PREP(SPMMC_SD_READ_CRC_DELAY,
580 						       host->tuning_info.rd_crc_dly);
581 			timing_cfg0 &= ~SPMMC_SD_READ_DATA_DELAY;
582 			timing_cfg0 |= FIELD_PREP(SPMMC_SD_READ_DATA_DELAY,
583 						       host->tuning_info.rd_dat_dly);
584 			timing_cfg0 &= ~SPMMC_SD_READ_RESPONSE_DELAY;
585 			timing_cfg0 |= FIELD_PREP(SPMMC_SD_READ_RESPONSE_DELAY,
586 						       host->tuning_info.rd_rsp_dly);
587 			timing_cfg0 &= ~SPMMC_SD_WRITE_COMMAND_DELAY;
588 			timing_cfg0 |= FIELD_PREP(SPMMC_SD_WRITE_COMMAND_DELAY,
589 						       host->tuning_info.wr_cmd_dly);
590 			timing_cfg0 &= ~SPMMC_SD_WRITE_DATA_DELAY;
591 			timing_cfg0 |= FIELD_PREP(SPMMC_SD_WRITE_DATA_DELAY,
592 						       host->tuning_info.wr_dat_dly);
593 			writel(timing_cfg0, host->base + SPMMC_SD_TIMING_CONFIG0_REG);
594 		}
595 	} else if (data) {
596 		data->error = 0;
597 		data->bytes_xfered = data->blocks * data->blksz;
598 	}
599 	host->tuning_info.need_tuning = ret;
600 
601 	return ret;
602 }
603 
604 /*
605  * the strategy is:
606  * 1. if several continuous delays are acceptable, we choose a middle one;
607  * 2. otherwise, we choose the first one.
608  */
609 static inline int spmmc_find_best_delay(u8 candidate_dly)
610 {
611 	int f, w, value;
612 
613 	if (!candidate_dly)
614 		return 0;
615 	f = ffs(candidate_dly) - 1;
616 	w = hweight8(candidate_dly);
617 	value = ((1 << w) - 1) << f;
618 	if (0xff == (value & ~candidate_dly))
619 		return (f + w / 2);
620 	else
621 		return (f);
622 }
623 
624 static void spmmc_xfer_data_pio(struct spmmc_host *host, struct mmc_data *data)
625 {
626 	u32 *buf;
627 	int data_left = data->blocks * data->blksz;
628 	int consumed, remain;
629 
630 	struct sg_mapping_iter sg_miter;
631 	unsigned int flags = 0;
632 
633 	if (data->flags & MMC_DATA_WRITE)
634 		flags |= SG_MITER_FROM_SG;
635 	else
636 		flags |= SG_MITER_TO_SG;
637 	sg_miter_start(&sg_miter, data->sg, data->sg_len, flags);
638 	while (data_left > 0) {
639 		consumed = 0;
640 		if (!sg_miter_next(&sg_miter))
641 			break;
642 		buf = sg_miter.addr;
643 		remain = sg_miter.length;
644 		do {
645 			if (data->flags & MMC_DATA_WRITE) {
646 				if (spmmc_wait_txbuf_empty(host))
647 					goto done;
648 				writel(*buf, host->base + SPMMC_SD_PIODATATX_REG);
649 			} else {
650 				if (spmmc_wait_rxbuf_full(host))
651 					goto done;
652 				*buf = readl(host->base + SPMMC_SD_PIODATARX_REG);
653 			}
654 			buf++;
655 			/* tx/rx 4 bytes one time in pio mode */
656 			consumed += 4;
657 			remain -= 4;
658 		} while (remain);
659 		sg_miter.consumed = consumed;
660 		data_left -= consumed;
661 	}
662 done:
663 	sg_miter_stop(&sg_miter);
664 }
665 
666 static void spmmc_controller_init(struct spmmc_host *host)
667 {
668 	u32 value;
669 	int ret = reset_control_assert(host->rstc);
670 
671 	if (!ret) {
672 		usleep_range(1000, 1250);
673 		ret = reset_control_deassert(host->rstc);
674 	}
675 
676 	value = readl(host->base + SPMMC_CARD_MEDIATYPE_SRCDST_REG);
677 	value &= ~SPMMC_MEDIA_TYPE;
678 	value |= FIELD_PREP(SPMMC_MEDIA_TYPE, SPMMC_MEDIA_SD);
679 	writel(value, host->base + SPMMC_CARD_MEDIATYPE_SRCDST_REG);
680 }
681 
682 /*
683  * 1. unmap scatterlist if needed;
684  * 2. get response & check error conditions;
685  * 3. notify mmc layer the request is done
686  */
687 static void spmmc_finish_request(struct spmmc_host *host, struct mmc_request *mrq)
688 {
689 	struct mmc_command *cmd;
690 	struct mmc_data *data;
691 
692 	if (!mrq)
693 		return;
694 
695 	cmd = mrq->cmd;
696 	data = mrq->data;
697 
698 	if (data && SPMMC_DMA_MODE == host->dmapio_mode) {
699 		dma_unmap_sg(host->mmc->parent, data->sg, data->sg_len, mmc_get_dma_dir(data));
700 		host->dma_use_int = 0;
701 	}
702 
703 	spmmc_get_rsp(host, cmd);
704 	spmmc_check_error(host, mrq);
705 	if (mrq->stop)
706 		spmmc_send_stop_cmd(host);
707 
708 	host->mrq = NULL;
709 	mmc_request_done(host->mmc, mrq);
710 }
711 
712 /* Interrupt Service Routine */
713 static irqreturn_t spmmc_irq(int irq, void *dev_id)
714 {
715 	struct spmmc_host *host = dev_id;
716 	u32 value = readl(host->base + SPMMC_SD_INT_REG);
717 
718 	if ((value & SPMMC_SDINT_SDCMP) && (value & SPMMC_SDINT_SDCMPEN)) {
719 		value &= ~SPMMC_SDINT_SDCMPEN;
720 		value |= SPMMC_SDINT_SDCMPCLR;
721 		writel(value, host->base + SPMMC_SD_INT_REG);
722 		return IRQ_WAKE_THREAD;
723 	}
724 	return IRQ_HANDLED;
725 }
726 
727 static void spmmc_request(struct mmc_host *mmc, struct mmc_request *mrq)
728 {
729 	struct spmmc_host *host = mmc_priv(mmc);
730 	struct mmc_data *data;
731 	struct mmc_command *cmd;
732 
733 	host->mrq = mrq;
734 	data = mrq->data;
735 	cmd = mrq->cmd;
736 
737 	spmmc_prepare_cmd(host, cmd);
738 	/* we need manually read response R2. */
739 	if (cmd->flags & MMC_RSP_136) {
740 		spmmc_trigger_transaction(host);
741 		spmmc_get_rsp(host, cmd);
742 		spmmc_wait_finish(host);
743 		spmmc_check_error(host, mrq);
744 		host->mrq = NULL;
745 		mmc_request_done(host->mmc, mrq);
746 	} else {
747 		if (data)
748 			spmmc_prepare_data(host, data);
749 
750 		if (host->dmapio_mode == SPMMC_PIO_MODE && data) {
751 			u32 value;
752 			/* pio data transfer do not use interrupt */
753 			value = readl(host->base + SPMMC_SD_INT_REG);
754 			value &= ~SPMMC_SDINT_SDCMPEN;
755 			writel(value, host->base + SPMMC_SD_INT_REG);
756 			spmmc_trigger_transaction(host);
757 			spmmc_xfer_data_pio(host, data);
758 			spmmc_wait_finish(host);
759 			spmmc_finish_request(host, mrq);
760 		} else {
761 			if (host->dma_use_int) {
762 				spmmc_trigger_transaction(host);
763 			} else {
764 				spmmc_trigger_transaction(host);
765 				spmmc_wait_finish(host);
766 				spmmc_finish_request(host, mrq);
767 			}
768 		}
769 	}
770 }
771 
772 static void spmmc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
773 {
774 	struct spmmc_host *host = (struct spmmc_host *)mmc_priv(mmc);
775 
776 	spmmc_set_bus_clk(host, ios->clock);
777 	spmmc_set_bus_timing(host, ios->timing);
778 	spmmc_set_bus_width(host, ios->bus_width);
779 	/* ensure mode is correct, because we might have hw reset the controller */
780 	spmmc_set_sdmmc_mode(host);
781 }
782 
783 /*
784  * Return values for the get_cd callback should be:
785  *   0 for a absent card
786  *   1 for a present card
787  *   -ENOSYS when not supported (equal to NULL callback)
788  *   or a negative errno value when something bad happened
789  */
790 static int spmmc_get_cd(struct mmc_host *mmc)
791 {
792 	int ret = 0;
793 
794 	if (mmc_can_gpio_cd(mmc))
795 		ret = mmc_gpio_get_cd(mmc);
796 
797 	if (ret < 0)
798 		ret = 0;
799 
800 	return ret;
801 }
802 
803 static int spmmc_execute_tuning(struct mmc_host *mmc, u32 opcode)
804 {
805 	struct spmmc_host *host = mmc_priv(mmc);
806 	u8 smpl_dly = 0, candidate_dly = 0;
807 	u32 value;
808 
809 	host->tuning_info.enable_tuning = 0;
810 	do {
811 		value = readl(host->base + SPMMC_SD_TIMING_CONFIG0_REG);
812 		value &= ~SPMMC_SD_READ_RESPONSE_DELAY;
813 		value |= FIELD_PREP(SPMMC_SD_READ_RESPONSE_DELAY, smpl_dly);
814 		value &= ~SPMMC_SD_READ_DATA_DELAY;
815 		value |= FIELD_PREP(SPMMC_SD_READ_DATA_DELAY, smpl_dly);
816 		value &= ~SPMMC_SD_READ_CRC_DELAY;
817 		value |= FIELD_PREP(SPMMC_SD_READ_CRC_DELAY, smpl_dly);
818 		writel(value, host->base + SPMMC_SD_TIMING_CONFIG0_REG);
819 
820 		if (!mmc_send_tuning(mmc, opcode, NULL)) {
821 			candidate_dly |= (1 << smpl_dly);
822 			break;
823 		}
824 	} while (smpl_dly++ <= SPMMC_MAX_TUNABLE_DLY);
825 	host->tuning_info.enable_tuning = 1;
826 
827 	if (candidate_dly) {
828 		smpl_dly = spmmc_find_best_delay(candidate_dly);
829 		value = readl(host->base + SPMMC_SD_TIMING_CONFIG0_REG);
830 		value &= ~SPMMC_SD_READ_RESPONSE_DELAY;
831 		value |= FIELD_PREP(SPMMC_SD_READ_RESPONSE_DELAY, smpl_dly);
832 		value &= ~SPMMC_SD_READ_DATA_DELAY;
833 		value |= FIELD_PREP(SPMMC_SD_READ_DATA_DELAY, smpl_dly);
834 		value &= ~SPMMC_SD_READ_CRC_DELAY;
835 		value |= FIELD_PREP(SPMMC_SD_READ_CRC_DELAY, smpl_dly);
836 		writel(value, host->base + SPMMC_SD_TIMING_CONFIG0_REG);
837 		return 0;
838 	}
839 
840 	return -EIO;
841 }
842 
843 static const struct mmc_host_ops spmmc_ops = {
844 	.request = spmmc_request,
845 	.set_ios = spmmc_set_ios,
846 	.get_cd = spmmc_get_cd,
847 	.execute_tuning = spmmc_execute_tuning,
848 };
849 
850 static irqreturn_t spmmc_func_finish_req(int irq, void *dev_id)
851 {
852 	struct spmmc_host *host = dev_id;
853 
854 	spmmc_finish_request(host, host->mrq);
855 
856 	return IRQ_HANDLED;
857 }
858 
859 static int spmmc_drv_probe(struct platform_device *pdev)
860 {
861 	struct mmc_host *mmc;
862 	struct resource *res;
863 	struct spmmc_host *host;
864 	int ret = 0;
865 
866 	mmc = devm_mmc_alloc_host(&pdev->dev, sizeof(struct spmmc_host));
867 	if (!mmc)
868 		return -ENOMEM;
869 
870 	host = mmc_priv(mmc);
871 	host->mmc = mmc;
872 	host->dmapio_mode = SPMMC_DMA_MODE;
873 	host->dma_int_threshold = 1024;
874 
875 	host->base = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
876 	if (IS_ERR(host->base))
877 		return PTR_ERR(host->base);
878 
879 	host->clk = devm_clk_get(&pdev->dev, NULL);
880 	if (IS_ERR(host->clk))
881 		return dev_err_probe(&pdev->dev, PTR_ERR(host->clk), "clk get fail\n");
882 
883 	host->rstc = devm_reset_control_get_exclusive(&pdev->dev, NULL);
884 	if (IS_ERR(host->rstc))
885 		return dev_err_probe(&pdev->dev, PTR_ERR(host->rstc), "rst get fail\n");
886 
887 	host->irq = platform_get_irq(pdev, 0);
888 	if (host->irq < 0)
889 		return host->irq;
890 
891 	ret = devm_request_threaded_irq(&pdev->dev, host->irq,
892 					spmmc_irq, spmmc_func_finish_req, IRQF_SHARED,
893 			NULL, host);
894 	if (ret)
895 		return ret;
896 
897 	ret = clk_prepare_enable(host->clk);
898 	if (ret)
899 		return dev_err_probe(&pdev->dev, ret, "failed to enable clk\n");
900 
901 	ret = mmc_of_parse(mmc);
902 	if (ret)
903 		goto clk_disable;
904 
905 	mmc->ops = &spmmc_ops;
906 	mmc->f_min = SPMMC_MIN_CLK;
907 	if (mmc->f_max > SPMMC_MAX_CLK)
908 		mmc->f_max = SPMMC_MAX_CLK;
909 
910 	ret = mmc_regulator_get_supply(mmc);
911 	if (ret)
912 		goto clk_disable;
913 
914 	if (!mmc->ocr_avail)
915 		mmc->ocr_avail = MMC_VDD_32_33 | MMC_VDD_33_34;
916 	mmc->max_seg_size = SPMMC_MAX_BLK_COUNT * 512;
917 	mmc->max_segs = SPMMC_MAX_DMA_MEMORY_SECTORS;
918 	mmc->max_req_size = SPMMC_MAX_BLK_COUNT * 512;
919 	mmc->max_blk_size = 512;
920 	mmc->max_blk_count = SPMMC_MAX_BLK_COUNT;
921 
922 	dev_set_drvdata(&pdev->dev, host);
923 	spmmc_controller_init(host);
924 	spmmc_set_sdmmc_mode(host);
925 	host->tuning_info.enable_tuning = 1;
926 	pm_runtime_set_active(&pdev->dev);
927 	pm_runtime_enable(&pdev->dev);
928 	ret = mmc_add_host(mmc);
929 	if (ret)
930 		goto pm_disable;
931 
932 	return 0;
933 
934 pm_disable:
935 	pm_runtime_disable(&pdev->dev);
936 
937 clk_disable:
938 	clk_disable_unprepare(host->clk);
939 	return ret;
940 }
941 
942 static void spmmc_drv_remove(struct platform_device *dev)
943 {
944 	struct spmmc_host *host = platform_get_drvdata(dev);
945 
946 	mmc_remove_host(host->mmc);
947 	pm_runtime_get_sync(&dev->dev);
948 	clk_disable_unprepare(host->clk);
949 	pm_runtime_put_noidle(&dev->dev);
950 	pm_runtime_disable(&dev->dev);
951 }
952 
953 static int spmmc_pm_runtime_suspend(struct device *dev)
954 {
955 	struct spmmc_host *host;
956 
957 	host = dev_get_drvdata(dev);
958 	clk_disable_unprepare(host->clk);
959 
960 	return 0;
961 }
962 
963 static int spmmc_pm_runtime_resume(struct device *dev)
964 {
965 	struct spmmc_host *host;
966 
967 	host = dev_get_drvdata(dev);
968 
969 	return clk_prepare_enable(host->clk);
970 }
971 
972 static DEFINE_RUNTIME_DEV_PM_OPS(spmmc_pm_ops, spmmc_pm_runtime_suspend,
973 							spmmc_pm_runtime_resume, NULL);
974 
975 static const struct of_device_id spmmc_of_table[] = {
976 	{
977 		.compatible = "sunplus,sp7021-mmc",
978 	},
979 	{/* sentinel */}
980 };
981 MODULE_DEVICE_TABLE(of, spmmc_of_table);
982 
983 static struct platform_driver spmmc_driver = {
984 	.probe = spmmc_drv_probe,
985 	.remove_new = spmmc_drv_remove,
986 	.driver = {
987 		.name = "spmmc",
988 		.pm = pm_ptr(&spmmc_pm_ops),
989 		.of_match_table = spmmc_of_table,
990 	},
991 };
992 module_platform_driver(spmmc_driver);
993 
994 MODULE_AUTHOR("Tony Huang <tonyhuang.sunplus@gmail.com>");
995 MODULE_AUTHOR("Li-hao Kuo <lhjeff911@gmail.com>");
996 MODULE_DESCRIPTION("Sunplus MMC controller driver");
997 MODULE_LICENSE("GPL");
998