1 // SPDX-License-Identifier: GPL-2.0
2 //
3 // Copyright (C) 2017-2018 Socionext Inc.
4 //   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
5 
6 #include <linux/bitfield.h>
7 #include <linux/bitops.h>
8 #include <linux/clk.h>
9 #include <linux/delay.h>
10 #include <linux/dma-mapping.h>
11 #include <linux/mfd/syscon.h>
12 #include <linux/mfd/tmio.h>
13 #include <linux/mmc/host.h>
14 #include <linux/module.h>
15 #include <linux/of.h>
16 #include <linux/pinctrl/consumer.h>
17 #include <linux/platform_device.h>
18 #include <linux/regmap.h>
19 #include <linux/reset.h>
20 
21 #include "tmio_mmc.h"
22 
23 #define   UNIPHIER_SD_CLK_CTL_DIV1024		BIT(16)
24 #define   UNIPHIER_SD_CLK_CTL_DIV1		BIT(10)
25 #define   UNIPHIER_SD_CLKCTL_OFFEN		BIT(9)  // auto SDCLK stop
26 #define UNIPHIER_SD_CC_EXT_MODE		0x1b0
27 #define   UNIPHIER_SD_CC_EXT_MODE_DMA		BIT(1)
28 #define UNIPHIER_SD_HOST_MODE		0x1c8
29 #define UNIPHIER_SD_VOLT		0x1e4
30 #define   UNIPHIER_SD_VOLT_MASK			GENMASK(1, 0)
31 #define   UNIPHIER_SD_VOLT_OFF			0
32 #define   UNIPHIER_SD_VOLT_330			1	// 3.3V signal
33 #define   UNIPHIER_SD_VOLT_180			2	// 1.8V signal
34 #define UNIPHIER_SD_DMA_MODE		0x410
35 #define   UNIPHIER_SD_DMA_MODE_DIR_MASK		GENMASK(17, 16)
36 #define   UNIPHIER_SD_DMA_MODE_DIR_TO_DEV	0
37 #define   UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV	1
38 #define   UNIPHIER_SD_DMA_MODE_WIDTH_MASK	GENMASK(5, 4)
39 #define   UNIPHIER_SD_DMA_MODE_WIDTH_8		0
40 #define   UNIPHIER_SD_DMA_MODE_WIDTH_16		1
41 #define   UNIPHIER_SD_DMA_MODE_WIDTH_32		2
42 #define   UNIPHIER_SD_DMA_MODE_WIDTH_64		3
43 #define   UNIPHIER_SD_DMA_MODE_ADDR_INC		BIT(0)	// 1: inc, 0: fixed
44 #define UNIPHIER_SD_DMA_CTL		0x414
45 #define   UNIPHIER_SD_DMA_CTL_START	BIT(0)	// start DMA (auto cleared)
46 #define UNIPHIER_SD_DMA_RST		0x418
47 #define   UNIPHIER_SD_DMA_RST_CH1	BIT(9)
48 #define   UNIPHIER_SD_DMA_RST_CH0	BIT(8)
49 #define UNIPHIER_SD_DMA_ADDR_L		0x440
50 #define UNIPHIER_SD_DMA_ADDR_H		0x444
51 
52 /* SD control */
53 #define UNIPHIER_SDCTRL_CHOFFSET	0x200
54 #define UNIPHIER_SDCTRL_MODE		0x30
55 #define   UNIPHIER_SDCTRL_MODE_UHS1MOD		BIT(15)
56 #define   UNIPHIER_SDCTRL_MODE_SDRSEL		BIT(14)
57 
58 /*
59  * IP is extended to support various features: built-in DMA engine,
60  * 1/1024 divisor, etc.
61  */
62 #define UNIPHIER_SD_CAP_EXTENDED_IP		BIT(0)
63 /* RX channel of the built-in DMA controller is broken (Pro5) */
64 #define UNIPHIER_SD_CAP_BROKEN_DMA_RX		BIT(1)
65 
66 struct uniphier_sd_priv {
67 	struct tmio_mmc_data tmio_data;
68 	struct pinctrl *pinctrl;
69 	struct pinctrl_state *pinstate_uhs;
70 	struct clk *clk;
71 	struct reset_control *rst;
72 	struct reset_control *rst_br;
73 	struct reset_control *rst_hw;
74 	struct dma_chan *chan;
75 	enum dma_data_direction dma_dir;
76 	struct regmap *sdctrl_regmap;
77 	u32 sdctrl_ch;
78 	unsigned long clk_rate;
79 	unsigned long caps;
80 };
81 
uniphier_sd_priv(struct tmio_mmc_host * host)82 static void *uniphier_sd_priv(struct tmio_mmc_host *host)
83 {
84 	return container_of(host->pdata, struct uniphier_sd_priv, tmio_data);
85 }
86 
uniphier_sd_dma_endisable(struct tmio_mmc_host * host,int enable)87 static void uniphier_sd_dma_endisable(struct tmio_mmc_host *host, int enable)
88 {
89 	sd_ctrl_write16(host, CTL_DMA_ENABLE, enable ? DMA_ENABLE_DMASDRW : 0);
90 }
91 
92 /* external DMA engine */
uniphier_sd_external_dma_issue(struct tasklet_struct * t)93 static void uniphier_sd_external_dma_issue(struct tasklet_struct *t)
94 {
95 	struct tmio_mmc_host *host = from_tasklet(host, t, dma_issue);
96 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
97 
98 	uniphier_sd_dma_endisable(host, 1);
99 	dma_async_issue_pending(priv->chan);
100 }
101 
uniphier_sd_external_dma_callback(void * param,const struct dmaengine_result * result)102 static void uniphier_sd_external_dma_callback(void *param,
103 					const struct dmaengine_result *result)
104 {
105 	struct tmio_mmc_host *host = param;
106 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
107 	unsigned long flags;
108 
109 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
110 		     priv->dma_dir);
111 
112 	spin_lock_irqsave(&host->lock, flags);
113 
114 	if (result->result == DMA_TRANS_NOERROR) {
115 		/*
116 		 * When the external DMA engine is enabled, strangely enough,
117 		 * the DATAEND flag can be asserted even if the DMA engine has
118 		 * not been kicked yet.  Enable the TMIO_STAT_DATAEND irq only
119 		 * after we make sure the DMA engine finishes the transfer,
120 		 * hence, in this callback.
121 		 */
122 		tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
123 	} else {
124 		host->data->error = -ETIMEDOUT;
125 		tmio_mmc_do_data_irq(host);
126 	}
127 
128 	spin_unlock_irqrestore(&host->lock, flags);
129 }
130 
uniphier_sd_external_dma_start(struct tmio_mmc_host * host,struct mmc_data * data)131 static void uniphier_sd_external_dma_start(struct tmio_mmc_host *host,
132 					   struct mmc_data *data)
133 {
134 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
135 	enum dma_transfer_direction dma_tx_dir;
136 	struct dma_async_tx_descriptor *desc;
137 	dma_cookie_t cookie;
138 	int sg_len;
139 
140 	if (!priv->chan)
141 		goto force_pio;
142 
143 	if (data->flags & MMC_DATA_READ) {
144 		priv->dma_dir = DMA_FROM_DEVICE;
145 		dma_tx_dir = DMA_DEV_TO_MEM;
146 	} else {
147 		priv->dma_dir = DMA_TO_DEVICE;
148 		dma_tx_dir = DMA_MEM_TO_DEV;
149 	}
150 
151 	sg_len = dma_map_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
152 			    priv->dma_dir);
153 	if (sg_len == 0)
154 		goto force_pio;
155 
156 	desc = dmaengine_prep_slave_sg(priv->chan, host->sg_ptr, sg_len,
157 				       dma_tx_dir, DMA_CTRL_ACK);
158 	if (!desc)
159 		goto unmap_sg;
160 
161 	desc->callback_result = uniphier_sd_external_dma_callback;
162 	desc->callback_param = host;
163 
164 	cookie = dmaengine_submit(desc);
165 	if (cookie < 0)
166 		goto unmap_sg;
167 
168 	host->dma_on = true;
169 
170 	return;
171 
172 unmap_sg:
173 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, host->sg_len,
174 		     priv->dma_dir);
175 force_pio:
176 	uniphier_sd_dma_endisable(host, 0);
177 }
178 
uniphier_sd_external_dma_enable(struct tmio_mmc_host * host,bool enable)179 static void uniphier_sd_external_dma_enable(struct tmio_mmc_host *host,
180 					    bool enable)
181 {
182 }
183 
uniphier_sd_external_dma_request(struct tmio_mmc_host * host,struct tmio_mmc_data * pdata)184 static void uniphier_sd_external_dma_request(struct tmio_mmc_host *host,
185 					     struct tmio_mmc_data *pdata)
186 {
187 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
188 	struct dma_chan *chan;
189 
190 	chan = dma_request_chan(mmc_dev(host->mmc), "rx-tx");
191 	if (IS_ERR(chan)) {
192 		dev_warn(mmc_dev(host->mmc),
193 			 "failed to request DMA channel. falling back to PIO\n");
194 		return;	/* just use PIO even for -EPROBE_DEFER */
195 	}
196 
197 	/* this driver uses a single channel for both RX an TX */
198 	priv->chan = chan;
199 	host->chan_rx = chan;
200 	host->chan_tx = chan;
201 
202 	tasklet_setup(&host->dma_issue, uniphier_sd_external_dma_issue);
203 }
204 
uniphier_sd_external_dma_release(struct tmio_mmc_host * host)205 static void uniphier_sd_external_dma_release(struct tmio_mmc_host *host)
206 {
207 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
208 
209 	if (priv->chan)
210 		dma_release_channel(priv->chan);
211 }
212 
uniphier_sd_external_dma_abort(struct tmio_mmc_host * host)213 static void uniphier_sd_external_dma_abort(struct tmio_mmc_host *host)
214 {
215 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
216 
217 	uniphier_sd_dma_endisable(host, 0);
218 
219 	if (priv->chan)
220 		dmaengine_terminate_sync(priv->chan);
221 }
222 
uniphier_sd_external_dma_dataend(struct tmio_mmc_host * host)223 static void uniphier_sd_external_dma_dataend(struct tmio_mmc_host *host)
224 {
225 	uniphier_sd_dma_endisable(host, 0);
226 
227 	tmio_mmc_do_data_irq(host);
228 }
229 
230 static const struct tmio_mmc_dma_ops uniphier_sd_external_dma_ops = {
231 	.start = uniphier_sd_external_dma_start,
232 	.enable = uniphier_sd_external_dma_enable,
233 	.request = uniphier_sd_external_dma_request,
234 	.release = uniphier_sd_external_dma_release,
235 	.abort = uniphier_sd_external_dma_abort,
236 	.dataend = uniphier_sd_external_dma_dataend,
237 };
238 
uniphier_sd_internal_dma_issue(struct tasklet_struct * t)239 static void uniphier_sd_internal_dma_issue(struct tasklet_struct *t)
240 {
241 	struct tmio_mmc_host *host = from_tasklet(host, t, dma_issue);
242 	unsigned long flags;
243 
244 	spin_lock_irqsave(&host->lock, flags);
245 	tmio_mmc_enable_mmc_irqs(host, TMIO_STAT_DATAEND);
246 	spin_unlock_irqrestore(&host->lock, flags);
247 
248 	uniphier_sd_dma_endisable(host, 1);
249 	writel(UNIPHIER_SD_DMA_CTL_START, host->ctl + UNIPHIER_SD_DMA_CTL);
250 }
251 
uniphier_sd_internal_dma_start(struct tmio_mmc_host * host,struct mmc_data * data)252 static void uniphier_sd_internal_dma_start(struct tmio_mmc_host *host,
253 					   struct mmc_data *data)
254 {
255 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
256 	struct scatterlist *sg = host->sg_ptr;
257 	dma_addr_t dma_addr;
258 	unsigned int dma_mode_dir;
259 	u32 dma_mode;
260 	int sg_len;
261 
262 	if ((data->flags & MMC_DATA_READ) && !host->chan_rx)
263 		goto force_pio;
264 
265 	if (WARN_ON(host->sg_len != 1))
266 		goto force_pio;
267 
268 	if (!IS_ALIGNED(sg->offset, 8))
269 		goto force_pio;
270 
271 	if (data->flags & MMC_DATA_READ) {
272 		priv->dma_dir = DMA_FROM_DEVICE;
273 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_FROM_DEV;
274 	} else {
275 		priv->dma_dir = DMA_TO_DEVICE;
276 		dma_mode_dir = UNIPHIER_SD_DMA_MODE_DIR_TO_DEV;
277 	}
278 
279 	sg_len = dma_map_sg(mmc_dev(host->mmc), sg, 1, priv->dma_dir);
280 	if (sg_len == 0)
281 		goto force_pio;
282 
283 	dma_mode = FIELD_PREP(UNIPHIER_SD_DMA_MODE_DIR_MASK, dma_mode_dir);
284 	dma_mode |= FIELD_PREP(UNIPHIER_SD_DMA_MODE_WIDTH_MASK,
285 			       UNIPHIER_SD_DMA_MODE_WIDTH_64);
286 	dma_mode |= UNIPHIER_SD_DMA_MODE_ADDR_INC;
287 
288 	writel(dma_mode, host->ctl + UNIPHIER_SD_DMA_MODE);
289 
290 	dma_addr = sg_dma_address(data->sg);
291 	writel(lower_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_L);
292 	writel(upper_32_bits(dma_addr), host->ctl + UNIPHIER_SD_DMA_ADDR_H);
293 
294 	host->dma_on = true;
295 
296 	return;
297 force_pio:
298 	uniphier_sd_dma_endisable(host, 0);
299 }
300 
uniphier_sd_internal_dma_enable(struct tmio_mmc_host * host,bool enable)301 static void uniphier_sd_internal_dma_enable(struct tmio_mmc_host *host,
302 					    bool enable)
303 {
304 }
305 
uniphier_sd_internal_dma_request(struct tmio_mmc_host * host,struct tmio_mmc_data * pdata)306 static void uniphier_sd_internal_dma_request(struct tmio_mmc_host *host,
307 					     struct tmio_mmc_data *pdata)
308 {
309 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
310 
311 	/*
312 	 * Due to a hardware bug, Pro5 cannot use DMA for RX.
313 	 * We can still use DMA for TX, but PIO for RX.
314 	 */
315 	if (!(priv->caps & UNIPHIER_SD_CAP_BROKEN_DMA_RX))
316 		host->chan_rx = (void *)0xdeadbeaf;
317 
318 	host->chan_tx = (void *)0xdeadbeaf;
319 
320 	tasklet_setup(&host->dma_issue, uniphier_sd_internal_dma_issue);
321 }
322 
uniphier_sd_internal_dma_release(struct tmio_mmc_host * host)323 static void uniphier_sd_internal_dma_release(struct tmio_mmc_host *host)
324 {
325 	/* Each value is set to zero to assume "disabling" each DMA */
326 	host->chan_rx = NULL;
327 	host->chan_tx = NULL;
328 }
329 
uniphier_sd_internal_dma_abort(struct tmio_mmc_host * host)330 static void uniphier_sd_internal_dma_abort(struct tmio_mmc_host *host)
331 {
332 	u32 tmp;
333 
334 	uniphier_sd_dma_endisable(host, 0);
335 
336 	tmp = readl(host->ctl + UNIPHIER_SD_DMA_RST);
337 	tmp &= ~(UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0);
338 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
339 
340 	tmp |= UNIPHIER_SD_DMA_RST_CH1 | UNIPHIER_SD_DMA_RST_CH0;
341 	writel(tmp, host->ctl + UNIPHIER_SD_DMA_RST);
342 }
343 
uniphier_sd_internal_dma_dataend(struct tmio_mmc_host * host)344 static void uniphier_sd_internal_dma_dataend(struct tmio_mmc_host *host)
345 {
346 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
347 
348 	uniphier_sd_dma_endisable(host, 0);
349 	dma_unmap_sg(mmc_dev(host->mmc), host->sg_ptr, 1, priv->dma_dir);
350 
351 	tmio_mmc_do_data_irq(host);
352 }
353 
354 static const struct tmio_mmc_dma_ops uniphier_sd_internal_dma_ops = {
355 	.start = uniphier_sd_internal_dma_start,
356 	.enable = uniphier_sd_internal_dma_enable,
357 	.request = uniphier_sd_internal_dma_request,
358 	.release = uniphier_sd_internal_dma_release,
359 	.abort = uniphier_sd_internal_dma_abort,
360 	.dataend = uniphier_sd_internal_dma_dataend,
361 };
362 
uniphier_sd_clk_enable(struct tmio_mmc_host * host)363 static int uniphier_sd_clk_enable(struct tmio_mmc_host *host)
364 {
365 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
366 	struct mmc_host *mmc = host->mmc;
367 	int ret;
368 
369 	ret = clk_prepare_enable(priv->clk);
370 	if (ret)
371 		return ret;
372 
373 	ret = clk_set_rate(priv->clk, ULONG_MAX);
374 	if (ret)
375 		goto disable_clk;
376 
377 	priv->clk_rate = clk_get_rate(priv->clk);
378 
379 	/* If max-frequency property is set, use it. */
380 	if (!mmc->f_max)
381 		mmc->f_max = priv->clk_rate;
382 
383 	/*
384 	 * 1/512 is the finest divisor in the original IP.  Newer versions
385 	 * also supports 1/1024 divisor. (UniPhier-specific extension)
386 	 */
387 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
388 		mmc->f_min = priv->clk_rate / 1024;
389 	else
390 		mmc->f_min = priv->clk_rate / 512;
391 
392 	ret = reset_control_deassert(priv->rst);
393 	if (ret)
394 		goto disable_clk;
395 
396 	ret = reset_control_deassert(priv->rst_br);
397 	if (ret)
398 		goto assert_rst;
399 
400 	return 0;
401 
402 assert_rst:
403 	reset_control_assert(priv->rst);
404 disable_clk:
405 	clk_disable_unprepare(priv->clk);
406 
407 	return ret;
408 }
409 
uniphier_sd_clk_disable(struct tmio_mmc_host * host)410 static void uniphier_sd_clk_disable(struct tmio_mmc_host *host)
411 {
412 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
413 
414 	reset_control_assert(priv->rst_br);
415 	reset_control_assert(priv->rst);
416 	clk_disable_unprepare(priv->clk);
417 }
418 
uniphier_sd_hw_reset(struct mmc_host * mmc)419 static void uniphier_sd_hw_reset(struct mmc_host *mmc)
420 {
421 	struct tmio_mmc_host *host = mmc_priv(mmc);
422 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
423 
424 	reset_control_assert(priv->rst_hw);
425 	/* For eMMC, minimum is 1us but give it 9us for good measure */
426 	udelay(9);
427 	reset_control_deassert(priv->rst_hw);
428 	/* For eMMC, minimum is 200us but give it 300us for good measure */
429 	usleep_range(300, 1000);
430 }
431 
uniphier_sd_speed_switch(struct tmio_mmc_host * host)432 static void uniphier_sd_speed_switch(struct tmio_mmc_host *host)
433 {
434 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
435 	unsigned int offset;
436 	u32 val = 0;
437 
438 	if (!(host->mmc->caps & MMC_CAP_UHS))
439 		return;
440 
441 	if (host->mmc->ios.timing == MMC_TIMING_UHS_SDR50 ||
442 	    host->mmc->ios.timing == MMC_TIMING_UHS_SDR104)
443 		val = UNIPHIER_SDCTRL_MODE_SDRSEL;
444 
445 	offset = UNIPHIER_SDCTRL_CHOFFSET * priv->sdctrl_ch
446 		+ UNIPHIER_SDCTRL_MODE;
447 	regmap_write_bits(priv->sdctrl_regmap, offset,
448 			  UNIPHIER_SDCTRL_MODE_SDRSEL, val);
449 }
450 
uniphier_sd_uhs_enable(struct tmio_mmc_host * host,bool uhs_en)451 static void uniphier_sd_uhs_enable(struct tmio_mmc_host *host, bool uhs_en)
452 {
453 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
454 	unsigned int offset;
455 	u32 val;
456 
457 	if (!(host->mmc->caps & MMC_CAP_UHS))
458 		return;
459 
460 	val = (uhs_en) ? UNIPHIER_SDCTRL_MODE_UHS1MOD : 0;
461 
462 	offset = UNIPHIER_SDCTRL_CHOFFSET * priv->sdctrl_ch
463 		+ UNIPHIER_SDCTRL_MODE;
464 	regmap_write_bits(priv->sdctrl_regmap, offset,
465 			  UNIPHIER_SDCTRL_MODE_UHS1MOD, val);
466 }
467 
uniphier_sd_set_clock(struct tmio_mmc_host * host,unsigned int clock)468 static void uniphier_sd_set_clock(struct tmio_mmc_host *host,
469 				  unsigned int clock)
470 {
471 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
472 	unsigned long divisor;
473 	u32 tmp;
474 
475 	tmp = readl(host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
476 
477 	/* stop the clock before changing its rate to avoid a glitch signal */
478 	tmp &= ~CLK_CTL_SCLKEN;
479 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
480 
481 	uniphier_sd_speed_switch(host);
482 
483 	if (clock == 0)
484 		return;
485 
486 	tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1024;
487 	tmp &= ~UNIPHIER_SD_CLK_CTL_DIV1;
488 	tmp &= ~CLK_CTL_DIV_MASK;
489 
490 	divisor = priv->clk_rate / clock;
491 
492 	/*
493 	 * In the original IP, bit[7:0] represents the divisor.
494 	 * bit7 set: 1/512, ... bit0 set:1/4, all bits clear: 1/2
495 	 *
496 	 * The IP does not define a way to achieve 1/1.  For UniPhier variants,
497 	 * bit10 is used for 1/1.  Newer versions of UniPhier variants use
498 	 * bit16 for 1/1024.
499 	 */
500 	if (divisor <= 1)
501 		tmp |= UNIPHIER_SD_CLK_CTL_DIV1;
502 	else if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP && divisor > 512)
503 		tmp |= UNIPHIER_SD_CLK_CTL_DIV1024;
504 	else
505 		tmp |= roundup_pow_of_two(divisor) >> 2;
506 
507 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
508 
509 	tmp |= CLK_CTL_SCLKEN;
510 	writel(tmp, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
511 }
512 
uniphier_sd_host_init(struct tmio_mmc_host * host)513 static void uniphier_sd_host_init(struct tmio_mmc_host *host)
514 {
515 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
516 	u32 val;
517 
518 	/*
519 	 * Connected to 32bit AXI.
520 	 * This register holds settings for SoC-specific internal bus
521 	 * connection.  What is worse, the register spec was changed,
522 	 * breaking the backward compatibility.  Write an appropriate
523 	 * value depending on a flag associated with a compatible string.
524 	 */
525 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
526 		val = 0x00000101;
527 	else
528 		val = 0x00000000;
529 
530 	writel(val, host->ctl + UNIPHIER_SD_HOST_MODE);
531 
532 	val = 0;
533 	/*
534 	 * If supported, the controller can automatically
535 	 * enable/disable the clock line to the card.
536 	 */
537 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
538 		val |= UNIPHIER_SD_CLKCTL_OFFEN;
539 
540 	writel(val, host->ctl + (CTL_SD_CARD_CLK_CTL << 1));
541 }
542 
uniphier_sd_start_signal_voltage_switch(struct mmc_host * mmc,struct mmc_ios * ios)543 static int uniphier_sd_start_signal_voltage_switch(struct mmc_host *mmc,
544 						   struct mmc_ios *ios)
545 {
546 	struct tmio_mmc_host *host = mmc_priv(mmc);
547 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
548 	struct pinctrl_state *pinstate = NULL;
549 	u32 val, tmp;
550 	bool uhs_en;
551 
552 	switch (ios->signal_voltage) {
553 	case MMC_SIGNAL_VOLTAGE_330:
554 		val = UNIPHIER_SD_VOLT_330;
555 		uhs_en = false;
556 		break;
557 	case MMC_SIGNAL_VOLTAGE_180:
558 		val = UNIPHIER_SD_VOLT_180;
559 		pinstate = priv->pinstate_uhs;
560 		uhs_en = true;
561 		break;
562 	default:
563 		return -ENOTSUPP;
564 	}
565 
566 	tmp = readl(host->ctl + UNIPHIER_SD_VOLT);
567 	tmp &= ~UNIPHIER_SD_VOLT_MASK;
568 	tmp |= FIELD_PREP(UNIPHIER_SD_VOLT_MASK, val);
569 	writel(tmp, host->ctl + UNIPHIER_SD_VOLT);
570 
571 	if (pinstate)
572 		pinctrl_select_state(priv->pinctrl, pinstate);
573 	else
574 		pinctrl_select_default_state(mmc_dev(mmc));
575 
576 	uniphier_sd_uhs_enable(host, uhs_en);
577 
578 	return 0;
579 }
580 
uniphier_sd_uhs_init(struct tmio_mmc_host * host)581 static int uniphier_sd_uhs_init(struct tmio_mmc_host *host)
582 {
583 	struct uniphier_sd_priv *priv = uniphier_sd_priv(host);
584 	struct device *dev = &host->pdev->dev;
585 	struct device_node *np = dev->of_node;
586 	struct of_phandle_args args;
587 	int ret;
588 
589 	priv->pinctrl = devm_pinctrl_get(mmc_dev(host->mmc));
590 	if (IS_ERR(priv->pinctrl))
591 		return PTR_ERR(priv->pinctrl);
592 
593 	priv->pinstate_uhs = pinctrl_lookup_state(priv->pinctrl, "uhs");
594 	if (IS_ERR(priv->pinstate_uhs))
595 		return PTR_ERR(priv->pinstate_uhs);
596 
597 	ret = of_parse_phandle_with_fixed_args(np,
598 					       "socionext,syscon-uhs-mode",
599 					       1, 0, &args);
600 	if (ret) {
601 		dev_err(dev, "Can't get syscon-uhs-mode property\n");
602 		return ret;
603 	}
604 	priv->sdctrl_regmap = syscon_node_to_regmap(args.np);
605 	of_node_put(args.np);
606 	if (IS_ERR(priv->sdctrl_regmap)) {
607 		dev_err(dev, "Can't map syscon-uhs-mode\n");
608 		return PTR_ERR(priv->sdctrl_regmap);
609 	}
610 	priv->sdctrl_ch = args.args[0];
611 
612 	return 0;
613 }
614 
uniphier_sd_probe(struct platform_device * pdev)615 static int uniphier_sd_probe(struct platform_device *pdev)
616 {
617 	struct device *dev = &pdev->dev;
618 	struct uniphier_sd_priv *priv;
619 	struct tmio_mmc_data *tmio_data;
620 	struct tmio_mmc_host *host;
621 	int irq, ret;
622 
623 	irq = platform_get_irq(pdev, 0);
624 	if (irq < 0)
625 		return irq;
626 
627 	priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
628 	if (!priv)
629 		return -ENOMEM;
630 
631 	priv->caps = (unsigned long)of_device_get_match_data(dev);
632 
633 	priv->clk = devm_clk_get(dev, NULL);
634 	if (IS_ERR(priv->clk)) {
635 		dev_err(dev, "failed to get clock\n");
636 		return PTR_ERR(priv->clk);
637 	}
638 
639 	priv->rst = devm_reset_control_get_shared(dev, "host");
640 	if (IS_ERR(priv->rst)) {
641 		dev_err(dev, "failed to get host reset\n");
642 		return PTR_ERR(priv->rst);
643 	}
644 
645 	/* old version has one more reset */
646 	if (!(priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)) {
647 		priv->rst_br = devm_reset_control_get_shared(dev, "bridge");
648 		if (IS_ERR(priv->rst_br)) {
649 			dev_err(dev, "failed to get bridge reset\n");
650 			return PTR_ERR(priv->rst_br);
651 		}
652 	}
653 
654 	tmio_data = &priv->tmio_data;
655 	tmio_data->flags |= TMIO_MMC_32BIT_DATA_PORT;
656 	tmio_data->flags |= TMIO_MMC_USE_BUSY_TIMEOUT;
657 
658 	host = tmio_mmc_host_alloc(pdev, tmio_data);
659 	if (IS_ERR(host))
660 		return PTR_ERR(host);
661 
662 	if (host->mmc->caps & MMC_CAP_HW_RESET) {
663 		priv->rst_hw = devm_reset_control_get_exclusive(dev, "hw");
664 		if (IS_ERR(priv->rst_hw)) {
665 			dev_err(dev, "failed to get hw reset\n");
666 			ret = PTR_ERR(priv->rst_hw);
667 			goto free_host;
668 		}
669 		host->ops.card_hw_reset = uniphier_sd_hw_reset;
670 	}
671 
672 	if (host->mmc->caps & MMC_CAP_UHS) {
673 		ret = uniphier_sd_uhs_init(host);
674 		if (ret) {
675 			dev_warn(dev,
676 				 "failed to setup UHS (error %d).  Disabling UHS.",
677 				 ret);
678 			host->mmc->caps &= ~MMC_CAP_UHS;
679 		} else {
680 			host->ops.start_signal_voltage_switch =
681 				uniphier_sd_start_signal_voltage_switch;
682 		}
683 	}
684 
685 	if (priv->caps & UNIPHIER_SD_CAP_EXTENDED_IP)
686 		host->dma_ops = &uniphier_sd_internal_dma_ops;
687 	else
688 		host->dma_ops = &uniphier_sd_external_dma_ops;
689 
690 	host->bus_shift = 1;
691 	host->clk_enable = uniphier_sd_clk_enable;
692 	host->clk_disable = uniphier_sd_clk_disable;
693 	host->set_clock = uniphier_sd_set_clock;
694 
695 	ret = uniphier_sd_clk_enable(host);
696 	if (ret)
697 		goto free_host;
698 
699 	uniphier_sd_host_init(host);
700 
701 	tmio_data->ocr_mask = MMC_VDD_32_33 | MMC_VDD_33_34;
702 	if (host->mmc->caps & MMC_CAP_UHS)
703 		tmio_data->ocr_mask |= MMC_VDD_165_195;
704 
705 	tmio_data->max_segs = 1;
706 	tmio_data->max_blk_count = U16_MAX;
707 
708 	sd_ctrl_write32_as_16_and_16(host, CTL_IRQ_MASK, TMIO_MASK_ALL);
709 
710 	ret = devm_request_irq(dev, irq, tmio_mmc_irq, IRQF_SHARED,
711 			       dev_name(dev), host);
712 	if (ret)
713 		goto disable_clk;
714 
715 	ret = tmio_mmc_host_probe(host);
716 	if (ret)
717 		goto disable_clk;
718 
719 	return 0;
720 
721 disable_clk:
722 	uniphier_sd_clk_disable(host);
723 free_host:
724 	tmio_mmc_host_free(host);
725 
726 	return ret;
727 }
728 
uniphier_sd_remove(struct platform_device * pdev)729 static void uniphier_sd_remove(struct platform_device *pdev)
730 {
731 	struct tmio_mmc_host *host = platform_get_drvdata(pdev);
732 
733 	tmio_mmc_host_remove(host);
734 	uniphier_sd_clk_disable(host);
735 	tmio_mmc_host_free(host);
736 }
737 
738 static const struct of_device_id uniphier_sd_match[] = {
739 	{
740 		.compatible = "socionext,uniphier-sd-v2.91",
741 	},
742 	{
743 		.compatible = "socionext,uniphier-sd-v3.1",
744 		.data = (void *)(UNIPHIER_SD_CAP_EXTENDED_IP |
745 				 UNIPHIER_SD_CAP_BROKEN_DMA_RX),
746 	},
747 	{
748 		.compatible = "socionext,uniphier-sd-v3.1.1",
749 		.data = (void *)UNIPHIER_SD_CAP_EXTENDED_IP,
750 	},
751 	{ /* sentinel */ }
752 };
753 MODULE_DEVICE_TABLE(of, uniphier_sd_match);
754 
755 static struct platform_driver uniphier_sd_driver = {
756 	.probe = uniphier_sd_probe,
757 	.remove_new = uniphier_sd_remove,
758 	.driver = {
759 		.name = "uniphier-sd",
760 		.probe_type = PROBE_PREFER_ASYNCHRONOUS,
761 		.of_match_table = uniphier_sd_match,
762 	},
763 };
764 module_platform_driver(uniphier_sd_driver);
765 
766 MODULE_AUTHOR("Masahiro Yamada <yamada.masahiro@socionext.com>");
767 MODULE_DESCRIPTION("UniPhier SD/eMMC host controller driver");
768 MODULE_LICENSE("GPL v2");
769