1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Support for SDHCI on STMicroelectronics SoCs
4 *
5 * Copyright (C) 2014 STMicroelectronics Ltd
6 * Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>
7 * Contributors: Peter Griffin <peter.griffin@linaro.org>
8 *
9 * Based on sdhci-cns3xxx.c
10 */
11
12 #include <linux/io.h>
13 #include <linux/of.h>
14 #include <linux/module.h>
15 #include <linux/err.h>
16 #include <linux/mmc/host.h>
17 #include <linux/reset.h>
18 #include "sdhci-pltfm.h"
19
20 struct st_mmc_platform_data {
21 struct reset_control *rstc;
22 struct clk *icnclk;
23 void __iomem *top_ioaddr;
24 };
25
26 /* MMCSS glue logic to setup the HC on some ST SoCs (e.g. STiH407 family) */
27
28 #define ST_MMC_CCONFIG_REG_1 0x400
29 #define ST_MMC_CCONFIG_TIMEOUT_CLK_UNIT BIT(24)
30 #define ST_MMC_CCONFIG_TIMEOUT_CLK_FREQ BIT(12)
31 #define ST_MMC_CCONFIG_TUNING_COUNT_DEFAULT BIT(8)
32 #define ST_MMC_CCONFIG_ASYNC_WAKEUP BIT(0)
33 #define ST_MMC_CCONFIG_1_DEFAULT \
34 ((ST_MMC_CCONFIG_TIMEOUT_CLK_UNIT) | \
35 (ST_MMC_CCONFIG_TIMEOUT_CLK_FREQ) | \
36 (ST_MMC_CCONFIG_TUNING_COUNT_DEFAULT))
37
38 #define ST_MMC_CCONFIG_REG_2 0x404
39 #define ST_MMC_CCONFIG_HIGH_SPEED BIT(28)
40 #define ST_MMC_CCONFIG_ADMA2 BIT(24)
41 #define ST_MMC_CCONFIG_8BIT BIT(20)
42 #define ST_MMC_CCONFIG_MAX_BLK_LEN 16
43 #define MAX_BLK_LEN_1024 1
44 #define MAX_BLK_LEN_2048 2
45 #define BASE_CLK_FREQ_200 0xc8
46 #define BASE_CLK_FREQ_100 0x64
47 #define BASE_CLK_FREQ_50 0x32
48 #define ST_MMC_CCONFIG_2_DEFAULT \
49 (ST_MMC_CCONFIG_HIGH_SPEED | ST_MMC_CCONFIG_ADMA2 | \
50 ST_MMC_CCONFIG_8BIT | \
51 (MAX_BLK_LEN_1024 << ST_MMC_CCONFIG_MAX_BLK_LEN))
52
53 #define ST_MMC_CCONFIG_REG_3 0x408
54 #define ST_MMC_CCONFIG_EMMC_SLOT_TYPE BIT(28)
55 #define ST_MMC_CCONFIG_64BIT BIT(24)
56 #define ST_MMC_CCONFIG_ASYNCH_INTR_SUPPORT BIT(20)
57 #define ST_MMC_CCONFIG_1P8_VOLT BIT(16)
58 #define ST_MMC_CCONFIG_3P0_VOLT BIT(12)
59 #define ST_MMC_CCONFIG_3P3_VOLT BIT(8)
60 #define ST_MMC_CCONFIG_SUSP_RES_SUPPORT BIT(4)
61 #define ST_MMC_CCONFIG_SDMA BIT(0)
62 #define ST_MMC_CCONFIG_3_DEFAULT \
63 (ST_MMC_CCONFIG_ASYNCH_INTR_SUPPORT | \
64 ST_MMC_CCONFIG_3P3_VOLT | \
65 ST_MMC_CCONFIG_SUSP_RES_SUPPORT | \
66 ST_MMC_CCONFIG_SDMA)
67
68 #define ST_MMC_CCONFIG_REG_4 0x40c
69 #define ST_MMC_CCONFIG_D_DRIVER BIT(20)
70 #define ST_MMC_CCONFIG_C_DRIVER BIT(16)
71 #define ST_MMC_CCONFIG_A_DRIVER BIT(12)
72 #define ST_MMC_CCONFIG_DDR50 BIT(8)
73 #define ST_MMC_CCONFIG_SDR104 BIT(4)
74 #define ST_MMC_CCONFIG_SDR50 BIT(0)
75 #define ST_MMC_CCONFIG_4_DEFAULT 0
76
77 #define ST_MMC_CCONFIG_REG_5 0x410
78 #define ST_MMC_CCONFIG_TUNING_FOR_SDR50 BIT(8)
79 #define RETUNING_TIMER_CNT_MAX 0xf
80 #define ST_MMC_CCONFIG_5_DEFAULT 0
81
82 /* I/O configuration for Arasan IP */
83 #define ST_MMC_GP_OUTPUT 0x450
84 #define ST_MMC_GP_OUTPUT_CD BIT(12)
85
86 #define ST_MMC_STATUS_R 0x460
87
88 #define ST_TOP_MMC_DLY_FIX_OFF(x) (x - 0x8)
89
90 /* TOP config registers to manage static and dynamic delay */
91 #define ST_TOP_MMC_TX_CLK_DLY ST_TOP_MMC_DLY_FIX_OFF(0x8)
92 #define ST_TOP_MMC_RX_CLK_DLY ST_TOP_MMC_DLY_FIX_OFF(0xc)
93 /* MMC delay control register */
94 #define ST_TOP_MMC_DLY_CTRL ST_TOP_MMC_DLY_FIX_OFF(0x18)
95 #define ST_TOP_MMC_DLY_CTRL_DLL_BYPASS_CMD BIT(0)
96 #define ST_TOP_MMC_DLY_CTRL_DLL_BYPASS_PH_SEL BIT(1)
97 #define ST_TOP_MMC_DLY_CTRL_TX_DLL_ENABLE BIT(8)
98 #define ST_TOP_MMC_DLY_CTRL_RX_DLL_ENABLE BIT(9)
99 #define ST_TOP_MMC_DLY_CTRL_ATUNE_NOT_CFG_DLY BIT(10)
100 #define ST_TOP_MMC_START_DLL_LOCK BIT(11)
101
102 /* register to provide the phase-shift value for DLL */
103 #define ST_TOP_MMC_TX_DLL_STEP_DLY ST_TOP_MMC_DLY_FIX_OFF(0x1c)
104 #define ST_TOP_MMC_RX_DLL_STEP_DLY ST_TOP_MMC_DLY_FIX_OFF(0x20)
105 #define ST_TOP_MMC_RX_CMD_STEP_DLY ST_TOP_MMC_DLY_FIX_OFF(0x24)
106
107 /* phase shift delay on the tx clk 2.188ns */
108 #define ST_TOP_MMC_TX_DLL_STEP_DLY_VALID 0x6
109
110 #define ST_TOP_MMC_DLY_MAX 0xf
111
112 #define ST_TOP_MMC_DYN_DLY_CONF \
113 (ST_TOP_MMC_DLY_CTRL_TX_DLL_ENABLE | \
114 ST_TOP_MMC_DLY_CTRL_ATUNE_NOT_CFG_DLY | \
115 ST_TOP_MMC_START_DLL_LOCK)
116
117 /*
118 * For clock speeds greater than 90MHz, we need to check that the
119 * DLL procedure has finished before switching to ultra-speed modes.
120 */
121 #define CLK_TO_CHECK_DLL_LOCK 90000000
122
st_mmcss_set_static_delay(void __iomem * ioaddr)123 static inline void st_mmcss_set_static_delay(void __iomem *ioaddr)
124 {
125 if (!ioaddr)
126 return;
127
128 writel_relaxed(0x0, ioaddr + ST_TOP_MMC_DLY_CTRL);
129 writel_relaxed(ST_TOP_MMC_DLY_MAX,
130 ioaddr + ST_TOP_MMC_TX_CLK_DLY);
131 }
132
133 /**
134 * st_mmcss_cconfig: configure the Arasan HC inside the flashSS.
135 * @np: dt device node.
136 * @host: sdhci host
137 * Description: this function is to configure the Arasan host controller.
138 * On some ST SoCs, i.e. STiH407 family, the MMC devices inside a dedicated
139 * flashSS sub-system which needs to be configured to be compliant to eMMC 4.5
140 * or eMMC4.3. This has to be done before registering the sdhci host.
141 */
st_mmcss_cconfig(struct device_node * np,struct sdhci_host * host)142 static void st_mmcss_cconfig(struct device_node *np, struct sdhci_host *host)
143 {
144 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
145 struct mmc_host *mhost = host->mmc;
146 u32 cconf2, cconf3, cconf4, cconf5;
147
148 if (!of_device_is_compatible(np, "st,sdhci-stih407"))
149 return;
150
151 cconf2 = ST_MMC_CCONFIG_2_DEFAULT;
152 cconf3 = ST_MMC_CCONFIG_3_DEFAULT;
153 cconf4 = ST_MMC_CCONFIG_4_DEFAULT;
154 cconf5 = ST_MMC_CCONFIG_5_DEFAULT;
155
156 writel_relaxed(ST_MMC_CCONFIG_1_DEFAULT,
157 host->ioaddr + ST_MMC_CCONFIG_REG_1);
158
159 /* Set clock frequency, default to 50MHz if max-frequency is not
160 * provided */
161
162 switch (mhost->f_max) {
163 case 200000000:
164 clk_set_rate(pltfm_host->clk, mhost->f_max);
165 cconf2 |= BASE_CLK_FREQ_200;
166 break;
167 case 100000000:
168 clk_set_rate(pltfm_host->clk, mhost->f_max);
169 cconf2 |= BASE_CLK_FREQ_100;
170 break;
171 default:
172 clk_set_rate(pltfm_host->clk, 50000000);
173 cconf2 |= BASE_CLK_FREQ_50;
174 }
175
176 writel_relaxed(cconf2, host->ioaddr + ST_MMC_CCONFIG_REG_2);
177
178 if (!mmc_card_is_removable(mhost))
179 cconf3 |= ST_MMC_CCONFIG_EMMC_SLOT_TYPE;
180 else
181 /* CARD _D ET_CTRL */
182 writel_relaxed(ST_MMC_GP_OUTPUT_CD,
183 host->ioaddr + ST_MMC_GP_OUTPUT);
184
185 if (mhost->caps & MMC_CAP_UHS_SDR50) {
186 /* use 1.8V */
187 cconf3 |= ST_MMC_CCONFIG_1P8_VOLT;
188 cconf4 |= ST_MMC_CCONFIG_SDR50;
189 /* Use tuning */
190 cconf5 |= ST_MMC_CCONFIG_TUNING_FOR_SDR50;
191 /* Max timeout for retuning */
192 cconf5 |= RETUNING_TIMER_CNT_MAX;
193 }
194
195 if (mhost->caps & MMC_CAP_UHS_SDR104) {
196 /*
197 * SDR104 implies the HC can support HS200 mode, so
198 * it's mandatory to use 1.8V
199 */
200 cconf3 |= ST_MMC_CCONFIG_1P8_VOLT;
201 cconf4 |= ST_MMC_CCONFIG_SDR104;
202 /* Max timeout for retuning */
203 cconf5 |= RETUNING_TIMER_CNT_MAX;
204 }
205
206 if (mhost->caps & MMC_CAP_UHS_DDR50)
207 cconf4 |= ST_MMC_CCONFIG_DDR50;
208
209 writel_relaxed(cconf3, host->ioaddr + ST_MMC_CCONFIG_REG_3);
210 writel_relaxed(cconf4, host->ioaddr + ST_MMC_CCONFIG_REG_4);
211 writel_relaxed(cconf5, host->ioaddr + ST_MMC_CCONFIG_REG_5);
212 }
213
st_mmcss_set_dll(void __iomem * ioaddr)214 static inline void st_mmcss_set_dll(void __iomem *ioaddr)
215 {
216 if (!ioaddr)
217 return;
218
219 writel_relaxed(ST_TOP_MMC_DYN_DLY_CONF, ioaddr + ST_TOP_MMC_DLY_CTRL);
220 writel_relaxed(ST_TOP_MMC_TX_DLL_STEP_DLY_VALID,
221 ioaddr + ST_TOP_MMC_TX_DLL_STEP_DLY);
222 }
223
st_mmcss_lock_dll(void __iomem * ioaddr)224 static int st_mmcss_lock_dll(void __iomem *ioaddr)
225 {
226 unsigned long curr, value;
227 unsigned long finish = jiffies + HZ;
228
229 /* Checks if the DLL procedure is finished */
230 do {
231 curr = jiffies;
232 value = readl(ioaddr + ST_MMC_STATUS_R);
233 if (value & 0x1)
234 return 0;
235
236 cpu_relax();
237 } while (!time_after_eq(curr, finish));
238
239 return -EBUSY;
240 }
241
sdhci_st_set_dll_for_clock(struct sdhci_host * host)242 static int sdhci_st_set_dll_for_clock(struct sdhci_host *host)
243 {
244 int ret = 0;
245 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
246 struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
247
248 if (host->clock > CLK_TO_CHECK_DLL_LOCK) {
249 st_mmcss_set_dll(pdata->top_ioaddr);
250 ret = st_mmcss_lock_dll(host->ioaddr);
251 }
252
253 return ret;
254 }
255
sdhci_st_set_uhs_signaling(struct sdhci_host * host,unsigned int uhs)256 static void sdhci_st_set_uhs_signaling(struct sdhci_host *host,
257 unsigned int uhs)
258 {
259 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
260 struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
261 u16 ctrl_2 = sdhci_readw(host, SDHCI_HOST_CONTROL2);
262 int ret = 0;
263
264 /* Select Bus Speed Mode for host */
265 ctrl_2 &= ~SDHCI_CTRL_UHS_MASK;
266 switch (uhs) {
267 /*
268 * Set V18_EN -- UHS modes do not work without this.
269 * does not change signaling voltage
270 */
271
272 case MMC_TIMING_UHS_SDR12:
273 st_mmcss_set_static_delay(pdata->top_ioaddr);
274 ctrl_2 |= SDHCI_CTRL_UHS_SDR12 | SDHCI_CTRL_VDD_180;
275 break;
276 case MMC_TIMING_UHS_SDR25:
277 st_mmcss_set_static_delay(pdata->top_ioaddr);
278 ctrl_2 |= SDHCI_CTRL_UHS_SDR25 | SDHCI_CTRL_VDD_180;
279 break;
280 case MMC_TIMING_UHS_SDR50:
281 st_mmcss_set_static_delay(pdata->top_ioaddr);
282 ctrl_2 |= SDHCI_CTRL_UHS_SDR50 | SDHCI_CTRL_VDD_180;
283 ret = sdhci_st_set_dll_for_clock(host);
284 break;
285 case MMC_TIMING_UHS_SDR104:
286 case MMC_TIMING_MMC_HS200:
287 st_mmcss_set_static_delay(pdata->top_ioaddr);
288 ctrl_2 |= SDHCI_CTRL_UHS_SDR104 | SDHCI_CTRL_VDD_180;
289 ret = sdhci_st_set_dll_for_clock(host);
290 break;
291 case MMC_TIMING_UHS_DDR50:
292 case MMC_TIMING_MMC_DDR52:
293 st_mmcss_set_static_delay(pdata->top_ioaddr);
294 ctrl_2 |= SDHCI_CTRL_UHS_DDR50 | SDHCI_CTRL_VDD_180;
295 break;
296 }
297
298 if (ret)
299 dev_warn(mmc_dev(host->mmc), "Error setting dll for clock "
300 "(uhs %d)\n", uhs);
301
302 dev_dbg(mmc_dev(host->mmc), "uhs %d, ctrl_2 %04X\n", uhs, ctrl_2);
303
304 sdhci_writew(host, ctrl_2, SDHCI_HOST_CONTROL2);
305 }
306
sdhci_st_readl(struct sdhci_host * host,int reg)307 static u32 sdhci_st_readl(struct sdhci_host *host, int reg)
308 {
309 u32 ret;
310
311 switch (reg) {
312 case SDHCI_CAPABILITIES:
313 ret = readl_relaxed(host->ioaddr + reg);
314 /* Support 3.3V and 1.8V */
315 ret &= ~SDHCI_CAN_VDD_300;
316 break;
317 default:
318 ret = readl_relaxed(host->ioaddr + reg);
319 }
320 return ret;
321 }
322
323 static const struct sdhci_ops sdhci_st_ops = {
324 .get_max_clock = sdhci_pltfm_clk_get_max_clock,
325 .set_clock = sdhci_set_clock,
326 .set_bus_width = sdhci_set_bus_width,
327 .read_l = sdhci_st_readl,
328 .reset = sdhci_reset,
329 .set_uhs_signaling = sdhci_st_set_uhs_signaling,
330 };
331
332 static const struct sdhci_pltfm_data sdhci_st_pdata = {
333 .ops = &sdhci_st_ops,
334 .quirks = SDHCI_QUIRK_NO_ENDATTR_IN_NOPDESC |
335 SDHCI_QUIRK_CAP_CLOCK_BASE_BROKEN |
336 SDHCI_QUIRK_NO_HISPD_BIT,
337 .quirks2 = SDHCI_QUIRK2_PRESET_VALUE_BROKEN |
338 SDHCI_QUIRK2_STOP_WITH_TC,
339 };
340
341
sdhci_st_probe(struct platform_device * pdev)342 static int sdhci_st_probe(struct platform_device *pdev)
343 {
344 struct device_node *np = pdev->dev.of_node;
345 struct sdhci_host *host;
346 struct st_mmc_platform_data *pdata;
347 struct sdhci_pltfm_host *pltfm_host;
348 struct clk *clk, *icnclk;
349 int ret = 0;
350 u16 host_version;
351 struct reset_control *rstc;
352
353 clk = devm_clk_get(&pdev->dev, "mmc");
354 if (IS_ERR(clk)) {
355 dev_err(&pdev->dev, "Peripheral clk not found\n");
356 return PTR_ERR(clk);
357 }
358
359 /* ICN clock isn't compulsory, but use it if it's provided. */
360 icnclk = devm_clk_get(&pdev->dev, "icn");
361 if (IS_ERR(icnclk))
362 icnclk = NULL;
363
364 rstc = devm_reset_control_get_optional_exclusive(&pdev->dev, NULL);
365 if (IS_ERR(rstc))
366 return PTR_ERR(rstc);
367 reset_control_deassert(rstc);
368
369 host = sdhci_pltfm_init(pdev, &sdhci_st_pdata, sizeof(*pdata));
370 if (IS_ERR(host)) {
371 dev_err(&pdev->dev, "Failed sdhci_pltfm_init\n");
372 ret = PTR_ERR(host);
373 goto err_pltfm_init;
374 }
375
376 pltfm_host = sdhci_priv(host);
377 pdata = sdhci_pltfm_priv(pltfm_host);
378 pdata->rstc = rstc;
379
380 ret = mmc_of_parse(host->mmc);
381 if (ret) {
382 dev_err(&pdev->dev, "Failed mmc_of_parse\n");
383 goto err_of;
384 }
385
386 ret = clk_prepare_enable(clk);
387 if (ret) {
388 dev_err(&pdev->dev, "Failed to prepare clock\n");
389 goto err_of;
390 }
391
392 ret = clk_prepare_enable(icnclk);
393 if (ret) {
394 dev_err(&pdev->dev, "Failed to prepare icn clock\n");
395 goto err_icnclk;
396 }
397
398 /* Configure the FlashSS Top registers for setting eMMC TX/RX delay */
399 pdata->top_ioaddr = devm_platform_ioremap_resource_byname(pdev, "top-mmc-delay");
400 if (IS_ERR(pdata->top_ioaddr))
401 pdata->top_ioaddr = NULL;
402
403 pltfm_host->clk = clk;
404 pdata->icnclk = icnclk;
405
406 /* Configure the Arasan HC inside the flashSS */
407 st_mmcss_cconfig(np, host);
408
409 ret = sdhci_add_host(host);
410 if (ret)
411 goto err_out;
412
413 host_version = readw_relaxed((host->ioaddr + SDHCI_HOST_VERSION));
414
415 dev_info(&pdev->dev, "SDHCI ST Initialised: Host Version: 0x%x Vendor Version 0x%x\n",
416 ((host_version & SDHCI_SPEC_VER_MASK) >> SDHCI_SPEC_VER_SHIFT),
417 ((host_version & SDHCI_VENDOR_VER_MASK) >>
418 SDHCI_VENDOR_VER_SHIFT));
419
420 return 0;
421
422 err_out:
423 clk_disable_unprepare(icnclk);
424 err_icnclk:
425 clk_disable_unprepare(clk);
426 err_of:
427 sdhci_pltfm_free(pdev);
428 err_pltfm_init:
429 reset_control_assert(rstc);
430
431 return ret;
432 }
433
sdhci_st_remove(struct platform_device * pdev)434 static void sdhci_st_remove(struct platform_device *pdev)
435 {
436 struct sdhci_host *host = platform_get_drvdata(pdev);
437 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
438 struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
439 struct reset_control *rstc = pdata->rstc;
440 struct clk *clk = pltfm_host->clk;
441
442 sdhci_pltfm_remove(pdev);
443
444 clk_disable_unprepare(pdata->icnclk);
445 clk_disable_unprepare(clk);
446
447 reset_control_assert(rstc);
448 }
449
450 #ifdef CONFIG_PM_SLEEP
sdhci_st_suspend(struct device * dev)451 static int sdhci_st_suspend(struct device *dev)
452 {
453 struct sdhci_host *host = dev_get_drvdata(dev);
454 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
455 struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
456 int ret;
457
458 if (host->tuning_mode != SDHCI_TUNING_MODE_3)
459 mmc_retune_needed(host->mmc);
460
461 ret = sdhci_suspend_host(host);
462 if (ret)
463 goto out;
464
465 reset_control_assert(pdata->rstc);
466
467 clk_disable_unprepare(pdata->icnclk);
468 clk_disable_unprepare(pltfm_host->clk);
469 out:
470 return ret;
471 }
472
sdhci_st_resume(struct device * dev)473 static int sdhci_st_resume(struct device *dev)
474 {
475 struct sdhci_host *host = dev_get_drvdata(dev);
476 struct sdhci_pltfm_host *pltfm_host = sdhci_priv(host);
477 struct st_mmc_platform_data *pdata = sdhci_pltfm_priv(pltfm_host);
478 struct device_node *np = dev->of_node;
479 int ret;
480
481 ret = clk_prepare_enable(pltfm_host->clk);
482 if (ret)
483 return ret;
484
485 ret = clk_prepare_enable(pdata->icnclk);
486 if (ret) {
487 clk_disable_unprepare(pltfm_host->clk);
488 return ret;
489 }
490
491 reset_control_deassert(pdata->rstc);
492
493 st_mmcss_cconfig(np, host);
494
495 return sdhci_resume_host(host);
496 }
497 #endif
498
499 static SIMPLE_DEV_PM_OPS(sdhci_st_pmops, sdhci_st_suspend, sdhci_st_resume);
500
501 static const struct of_device_id st_sdhci_match[] = {
502 { .compatible = "st,sdhci" },
503 {},
504 };
505
506 MODULE_DEVICE_TABLE(of, st_sdhci_match);
507
508 static struct platform_driver sdhci_st_driver = {
509 .probe = sdhci_st_probe,
510 .remove_new = sdhci_st_remove,
511 .driver = {
512 .name = "sdhci-st",
513 .probe_type = PROBE_PREFER_ASYNCHRONOUS,
514 .pm = &sdhci_st_pmops,
515 .of_match_table = st_sdhci_match,
516 },
517 };
518
519 module_platform_driver(sdhci_st_driver);
520
521 MODULE_DESCRIPTION("SDHCI driver for STMicroelectronics SoCs");
522 MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
523 MODULE_LICENSE("GPL v2");
524 MODULE_ALIAS("platform:sdhci-st");
525