xref: /openbmc/u-boot/drivers/mmc/sdhci-cadence.c (revision d66ff4ba)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2016 Socionext Inc.
4  *   Author: Masahiro Yamada <yamada.masahiro@socionext.com>
5  */
6 
7 #include <common.h>
8 #include <dm.h>
9 #include <linux/bitfield.h>
10 #include <linux/io.h>
11 #include <linux/iopoll.h>
12 #include <linux/sizes.h>
13 #include <linux/libfdt.h>
14 #include <mmc.h>
15 #include <sdhci.h>
16 
17 /* HRS - Host Register Set (specific to Cadence) */
18 #define SDHCI_CDNS_HRS04		0x10		/* PHY access port */
19 #define   SDHCI_CDNS_HRS04_ACK			BIT(26)
20 #define   SDHCI_CDNS_HRS04_RD			BIT(25)
21 #define   SDHCI_CDNS_HRS04_WR			BIT(24)
22 #define   SDHCI_CDNS_HRS04_RDATA		GENMASK(23, 16)
23 #define   SDHCI_CDNS_HRS04_WDATA		GENMASK(15, 8)
24 #define   SDHCI_CDNS_HRS04_ADDR			GENMASK(5, 0)
25 
26 #define SDHCI_CDNS_HRS06		0x18		/* eMMC control */
27 #define   SDHCI_CDNS_HRS06_TUNE_UP		BIT(15)
28 #define   SDHCI_CDNS_HRS06_TUNE			GENMASK(13, 8)
29 #define   SDHCI_CDNS_HRS06_MODE			GENMASK(2, 0)
30 #define   SDHCI_CDNS_HRS06_MODE_SD		0x0
31 #define   SDHCI_CDNS_HRS06_MODE_MMC_SDR		0x2
32 #define   SDHCI_CDNS_HRS06_MODE_MMC_DDR		0x3
33 #define   SDHCI_CDNS_HRS06_MODE_MMC_HS200	0x4
34 #define   SDHCI_CDNS_HRS06_MODE_MMC_HS400	0x5
35 #define   SDHCI_CDNS_HRS06_MODE_MMC_HS400ES	0x6
36 
37 /* SRS - Slot Register Set (SDHCI-compatible) */
38 #define SDHCI_CDNS_SRS_BASE		0x200
39 
40 /* PHY */
41 #define SDHCI_CDNS_PHY_DLY_SD_HS	0x00
42 #define SDHCI_CDNS_PHY_DLY_SD_DEFAULT	0x01
43 #define SDHCI_CDNS_PHY_DLY_UHS_SDR12	0x02
44 #define SDHCI_CDNS_PHY_DLY_UHS_SDR25	0x03
45 #define SDHCI_CDNS_PHY_DLY_UHS_SDR50	0x04
46 #define SDHCI_CDNS_PHY_DLY_UHS_DDR50	0x05
47 #define SDHCI_CDNS_PHY_DLY_EMMC_LEGACY	0x06
48 #define SDHCI_CDNS_PHY_DLY_EMMC_SDR	0x07
49 #define SDHCI_CDNS_PHY_DLY_EMMC_DDR	0x08
50 #define SDHCI_CDNS_PHY_DLY_SDCLK	0x0b
51 #define SDHCI_CDNS_PHY_DLY_HSMMC	0x0c
52 #define SDHCI_CDNS_PHY_DLY_STROBE	0x0d
53 
54 /*
55  * The tuned val register is 6 bit-wide, but not the whole of the range is
56  * available.  The range 0-42 seems to be available (then 43 wraps around to 0)
57  * but I am not quite sure if it is official.  Use only 0 to 39 for safety.
58  */
59 #define SDHCI_CDNS_MAX_TUNING_LOOP	40
60 
61 struct sdhci_cdns_plat {
62 	struct mmc_config cfg;
63 	struct mmc mmc;
64 	void __iomem *hrs_addr;
65 };
66 
67 struct sdhci_cdns_phy_cfg {
68 	const char *property;
69 	u8 addr;
70 };
71 
72 static const struct sdhci_cdns_phy_cfg sdhci_cdns_phy_cfgs[] = {
73 	{ "cdns,phy-input-delay-sd-highspeed", SDHCI_CDNS_PHY_DLY_SD_HS, },
74 	{ "cdns,phy-input-delay-legacy", SDHCI_CDNS_PHY_DLY_SD_DEFAULT, },
75 	{ "cdns,phy-input-delay-sd-uhs-sdr12", SDHCI_CDNS_PHY_DLY_UHS_SDR12, },
76 	{ "cdns,phy-input-delay-sd-uhs-sdr25", SDHCI_CDNS_PHY_DLY_UHS_SDR25, },
77 	{ "cdns,phy-input-delay-sd-uhs-sdr50", SDHCI_CDNS_PHY_DLY_UHS_SDR50, },
78 	{ "cdns,phy-input-delay-sd-uhs-ddr50", SDHCI_CDNS_PHY_DLY_UHS_DDR50, },
79 	{ "cdns,phy-input-delay-mmc-highspeed", SDHCI_CDNS_PHY_DLY_EMMC_SDR, },
80 	{ "cdns,phy-input-delay-mmc-ddr", SDHCI_CDNS_PHY_DLY_EMMC_DDR, },
81 	{ "cdns,phy-dll-delay-sdclk", SDHCI_CDNS_PHY_DLY_SDCLK, },
82 	{ "cdns,phy-dll-delay-sdclk-hsmmc", SDHCI_CDNS_PHY_DLY_HSMMC, },
83 	{ "cdns,phy-dll-delay-strobe", SDHCI_CDNS_PHY_DLY_STROBE, },
84 };
85 
86 static int sdhci_cdns_write_phy_reg(struct sdhci_cdns_plat *plat,
87 				    u8 addr, u8 data)
88 {
89 	void __iomem *reg = plat->hrs_addr + SDHCI_CDNS_HRS04;
90 	u32 tmp;
91 	int ret;
92 
93 	tmp = FIELD_PREP(SDHCI_CDNS_HRS04_WDATA, data) |
94 	      FIELD_PREP(SDHCI_CDNS_HRS04_ADDR, addr);
95 	writel(tmp, reg);
96 
97 	tmp |= SDHCI_CDNS_HRS04_WR;
98 	writel(tmp, reg);
99 
100 	ret = readl_poll_timeout(reg, tmp, tmp & SDHCI_CDNS_HRS04_ACK, 10);
101 	if (ret)
102 		return ret;
103 
104 	tmp &= ~SDHCI_CDNS_HRS04_WR;
105 	writel(tmp, reg);
106 
107 	return 0;
108 }
109 
110 static int sdhci_cdns_phy_init(struct sdhci_cdns_plat *plat,
111 				const void *fdt, int nodeoffset)
112 {
113 	const fdt32_t *prop;
114 	int ret, i;
115 
116 	for (i = 0; i < ARRAY_SIZE(sdhci_cdns_phy_cfgs); i++) {
117 		prop = fdt_getprop(fdt, nodeoffset,
118 				   sdhci_cdns_phy_cfgs[i].property, NULL);
119 		if (!prop)
120 			continue;
121 
122 		ret = sdhci_cdns_write_phy_reg(plat,
123 					       sdhci_cdns_phy_cfgs[i].addr,
124 					       fdt32_to_cpu(*prop));
125 		if (ret)
126 			return ret;
127 	}
128 
129 	return 0;
130 }
131 
132 static void sdhci_cdns_set_control_reg(struct sdhci_host *host)
133 {
134 	struct mmc *mmc = host->mmc;
135 	struct sdhci_cdns_plat *plat = dev_get_platdata(mmc->dev);
136 	unsigned int clock = mmc->clock;
137 	u32 mode, tmp;
138 
139 	/*
140 	 * REVISIT:
141 	 * The mode should be decided by MMC_TIMING_* like Linux, but
142 	 * U-Boot does not support timing.  Use the clock frequency instead.
143 	 */
144 	if (clock <= 26000000) {
145 		mode = SDHCI_CDNS_HRS06_MODE_SD; /* use this for Legacy */
146 	} else if (clock <= 52000000) {
147 		if (mmc->ddr_mode)
148 			mode = SDHCI_CDNS_HRS06_MODE_MMC_DDR;
149 		else
150 			mode = SDHCI_CDNS_HRS06_MODE_MMC_SDR;
151 	} else {
152 		if (mmc->ddr_mode)
153 			mode = SDHCI_CDNS_HRS06_MODE_MMC_HS400;
154 		else
155 			mode = SDHCI_CDNS_HRS06_MODE_MMC_HS200;
156 	}
157 
158 	tmp = readl(plat->hrs_addr + SDHCI_CDNS_HRS06);
159 	tmp &= ~SDHCI_CDNS_HRS06_MODE;
160 	tmp |= FIELD_PREP(SDHCI_CDNS_HRS06_MODE, mode);
161 	writel(tmp, plat->hrs_addr + SDHCI_CDNS_HRS06);
162 }
163 
164 static const struct sdhci_ops sdhci_cdns_ops = {
165 	.set_control_reg = sdhci_cdns_set_control_reg,
166 };
167 
168 static int sdhci_cdns_set_tune_val(struct sdhci_cdns_plat *plat,
169 				   unsigned int val)
170 {
171 	void __iomem *reg = plat->hrs_addr + SDHCI_CDNS_HRS06;
172 	u32 tmp;
173 
174 	if (WARN_ON(!FIELD_FIT(SDHCI_CDNS_HRS06_TUNE, val)))
175 		return -EINVAL;
176 
177 	tmp = readl(reg);
178 	tmp &= ~SDHCI_CDNS_HRS06_TUNE;
179 	tmp |= FIELD_PREP(SDHCI_CDNS_HRS06_TUNE, val);
180 	tmp |= SDHCI_CDNS_HRS06_TUNE_UP;
181 	writel(tmp, reg);
182 
183 	return readl_poll_timeout(reg, tmp, !(tmp & SDHCI_CDNS_HRS06_TUNE_UP),
184 				  1);
185 }
186 
187 static int __maybe_unused sdhci_cdns_execute_tuning(struct udevice *dev,
188 						    unsigned int opcode)
189 {
190 	struct sdhci_cdns_plat *plat = dev_get_platdata(dev);
191 	struct mmc *mmc = &plat->mmc;
192 	int cur_streak = 0;
193 	int max_streak = 0;
194 	int end_of_streak = 0;
195 	int i;
196 
197 	/*
198 	 * This handler only implements the eMMC tuning that is specific to
199 	 * this controller.  The tuning for SD timing should be handled by the
200 	 * SDHCI core.
201 	 */
202 	if (!IS_MMC(mmc))
203 		return -ENOTSUPP;
204 
205 	if (WARN_ON(opcode != MMC_CMD_SEND_TUNING_BLOCK_HS200))
206 		return -EINVAL;
207 
208 	for (i = 0; i < SDHCI_CDNS_MAX_TUNING_LOOP; i++) {
209 		if (sdhci_cdns_set_tune_val(plat, i) ||
210 		    mmc_send_tuning(mmc, opcode, NULL)) { /* bad */
211 			cur_streak = 0;
212 		} else { /* good */
213 			cur_streak++;
214 			if (cur_streak > max_streak) {
215 				max_streak = cur_streak;
216 				end_of_streak = i;
217 			}
218 		}
219 	}
220 
221 	if (!max_streak) {
222 		dev_err(dev, "no tuning point found\n");
223 		return -EIO;
224 	}
225 
226 	return sdhci_cdns_set_tune_val(plat, end_of_streak - max_streak / 2);
227 }
228 
229 static struct dm_mmc_ops sdhci_cdns_mmc_ops;
230 
231 static int sdhci_cdns_bind(struct udevice *dev)
232 {
233 	struct sdhci_cdns_plat *plat = dev_get_platdata(dev);
234 
235 	return sdhci_bind(dev, &plat->mmc, &plat->cfg);
236 }
237 
238 static int sdhci_cdns_probe(struct udevice *dev)
239 {
240 	DECLARE_GLOBAL_DATA_PTR;
241 	struct mmc_uclass_priv *upriv = dev_get_uclass_priv(dev);
242 	struct sdhci_cdns_plat *plat = dev_get_platdata(dev);
243 	struct sdhci_host *host = dev_get_priv(dev);
244 	fdt_addr_t base;
245 	int ret;
246 
247 	base = devfdt_get_addr(dev);
248 	if (base == FDT_ADDR_T_NONE)
249 		return -EINVAL;
250 
251 	plat->hrs_addr = devm_ioremap(dev, base, SZ_1K);
252 	if (!plat->hrs_addr)
253 		return -ENOMEM;
254 
255 	host->name = dev->name;
256 	host->ioaddr = plat->hrs_addr + SDHCI_CDNS_SRS_BASE;
257 	host->ops = &sdhci_cdns_ops;
258 	host->quirks |= SDHCI_QUIRK_WAIT_SEND_CMD;
259 	sdhci_cdns_mmc_ops = sdhci_ops;
260 #ifdef MMC_SUPPORTS_TUNING
261 	sdhci_cdns_mmc_ops.execute_tuning = sdhci_cdns_execute_tuning;
262 #endif
263 
264 	ret = mmc_of_parse(dev, &plat->cfg);
265 	if (ret)
266 		return ret;
267 
268 	ret = sdhci_cdns_phy_init(plat, gd->fdt_blob, dev_of_offset(dev));
269 	if (ret)
270 		return ret;
271 
272 	ret = sdhci_setup_cfg(&plat->cfg, host, 0, 0);
273 	if (ret)
274 		return ret;
275 
276 	upriv->mmc = &plat->mmc;
277 	host->mmc = &plat->mmc;
278 	host->mmc->priv = host;
279 
280 	return sdhci_probe(dev);
281 }
282 
283 static const struct udevice_id sdhci_cdns_match[] = {
284 	{ .compatible = "socionext,uniphier-sd4hc" },
285 	{ .compatible = "cdns,sd4hc" },
286 	{ /* sentinel */ }
287 };
288 
289 U_BOOT_DRIVER(sdhci_cdns) = {
290 	.name = "sdhci-cdns",
291 	.id = UCLASS_MMC,
292 	.of_match = sdhci_cdns_match,
293 	.bind = sdhci_cdns_bind,
294 	.probe = sdhci_cdns_probe,
295 	.priv_auto_alloc_size = sizeof(struct sdhci_host),
296 	.platdata_auto_alloc_size = sizeof(struct sdhci_cdns_plat),
297 	.ops = &sdhci_cdns_mmc_ops,
298 };
299