xref: /openbmc/u-boot/drivers/mmc/exynos_dw_mmc.c (revision 4d93617d)
1 /*
2  * (C) Copyright 2012 SAMSUNG Electronics
3  * Jaehoon Chung <jh80.chung@samsung.com>
4  *
5  * SPDX-License-Identifier:	GPL-2.0+
6  */
7 
8 #include <common.h>
9 #include <dwmmc.h>
10 #include <fdtdec.h>
11 #include <libfdt.h>
12 #include <malloc.h>
13 #include <asm/arch/dwmmc.h>
14 #include <asm/arch/clk.h>
15 #include <asm/arch/pinmux.h>
16 #include <asm/arch/power.h>
17 #include <asm/gpio.h>
18 #include <asm-generic/errno.h>
19 
20 #define	DWMMC_MAX_CH_NUM		4
21 #define	DWMMC_MAX_FREQ			52000000
22 #define	DWMMC_MIN_FREQ			400000
23 #define	DWMMC_MMC0_SDR_TIMING_VAL	0x03030001
24 #define	DWMMC_MMC2_SDR_TIMING_VAL	0x03020001
25 
26 /* Exynos implmentation specific drver private data */
27 struct dwmci_exynos_priv_data {
28 	u32 sdr_timing;
29 };
30 
31 /*
32  * Function used as callback function to initialise the
33  * CLKSEL register for every mmc channel.
34  */
35 static void exynos_dwmci_clksel(struct dwmci_host *host)
36 {
37 	struct dwmci_exynos_priv_data *priv = host->priv;
38 
39 	dwmci_writel(host, DWMCI_CLKSEL, priv->sdr_timing);
40 }
41 
42 unsigned int exynos_dwmci_get_clk(struct dwmci_host *host)
43 {
44 	unsigned long sclk;
45 	int8_t clk_div;
46 
47 	/*
48 	 * Since SDCLKIN is divided inside controller by the DIVRATIO
49 	 * value set in the CLKSEL register, we need to use the same output
50 	 * clock value to calculate the CLKDIV value.
51 	 * as per user manual:cclk_in = SDCLKIN / (DIVRATIO + 1)
52 	 */
53 	clk_div = ((dwmci_readl(host, DWMCI_CLKSEL) >> DWMCI_DIVRATIO_BIT)
54 			& DWMCI_DIVRATIO_MASK) + 1;
55 	sclk = get_mmc_clk(host->dev_index);
56 
57 	/*
58 	 * Assume to know divider value.
59 	 * When clock unit is broken, need to set "host->div"
60 	 */
61 	return sclk / clk_div / (host->div + 1);
62 }
63 
64 static void exynos_dwmci_board_init(struct dwmci_host *host)
65 {
66 	struct dwmci_exynos_priv_data *priv = host->priv;
67 
68 	if (host->quirks & DWMCI_QUIRK_DISABLE_SMU) {
69 		dwmci_writel(host, EMMCP_MPSBEGIN0, 0);
70 		dwmci_writel(host, EMMCP_SEND0, 0);
71 		dwmci_writel(host, EMMCP_CTRL0,
72 			     MPSCTRL_SECURE_READ_BIT |
73 			     MPSCTRL_SECURE_WRITE_BIT |
74 			     MPSCTRL_NON_SECURE_READ_BIT |
75 			     MPSCTRL_NON_SECURE_WRITE_BIT | MPSCTRL_VALID);
76 	}
77 
78 	/* Set to timing value at initial time */
79 	if (priv->sdr_timing)
80 		exynos_dwmci_clksel(host);
81 }
82 
83 static int exynos_dwmci_core_init(struct dwmci_host *host, int index)
84 {
85 	unsigned int div;
86 	unsigned long freq, sclk;
87 	struct dwmci_exynos_priv_data *priv = host->priv;
88 
89 	if (host->bus_hz)
90 		freq = host->bus_hz;
91 	else
92 		freq = DWMMC_MAX_FREQ;
93 
94 	/* request mmc clock vlaue of 52MHz.  */
95 	sclk = get_mmc_clk(index);
96 	div = DIV_ROUND_UP(sclk, freq);
97 	/* set the clock divisor for mmc */
98 	set_mmc_clk(index, div);
99 
100 	host->name = "EXYNOS DWMMC";
101 #ifdef CONFIG_EXYNOS5420
102 	host->quirks = DWMCI_QUIRK_DISABLE_SMU;
103 #endif
104 	host->board_init = exynos_dwmci_board_init;
105 
106 	if (!priv->sdr_timing) {
107 		if (index == 0)
108 			priv->sdr_timing = DWMMC_MMC0_SDR_TIMING_VAL;
109 		else if (index == 2)
110 			priv->sdr_timing = DWMMC_MMC2_SDR_TIMING_VAL;
111 	}
112 
113 	host->caps = MMC_MODE_DDR_52MHz;
114 	host->clksel = exynos_dwmci_clksel;
115 	host->dev_index = index;
116 	host->get_mmc_clk = exynos_dwmci_get_clk;
117 	/* Add the mmc channel to be registered with mmc core */
118 	if (add_dwmci(host, DWMMC_MAX_FREQ, DWMMC_MIN_FREQ)) {
119 		printf("DWMMC%d registration failed\n", index);
120 		return -1;
121 	}
122 	return 0;
123 }
124 
125 /*
126  * This function adds the mmc channel to be registered with mmc core.
127  * index -	mmc channel number.
128  * regbase -	register base address of mmc channel specified in 'index'.
129  * bus_width -	operating bus width of mmc channel specified in 'index'.
130  * clksel -	value to be written into CLKSEL register in case of FDT.
131  *		NULL in case od non-FDT.
132  */
133 int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32 clksel)
134 {
135 	struct dwmci_host *host = NULL;
136 	struct dwmci_exynos_priv_data *priv;
137 
138 	host = malloc(sizeof(struct dwmci_host));
139 	if (!host) {
140 		error("dwmci_host malloc fail!\n");
141 		return -ENOMEM;
142 	}
143 
144 	priv = malloc(sizeof(struct dwmci_exynos_priv_data));
145 	if (!priv) {
146 		error("dwmci_exynos_priv_data malloc fail!\n");
147 		return -ENOMEM;
148 	}
149 
150 	host->ioaddr = (void *)regbase;
151 	host->buswidth = bus_width;
152 
153 	if (clksel)
154 		priv->sdr_timing = clksel;
155 
156 	host->priv = priv;
157 
158 	return exynos_dwmci_core_init(host, index);
159 }
160 
161 #ifdef CONFIG_OF_CONTROL
162 static struct dwmci_host dwmci_host[DWMMC_MAX_CH_NUM];
163 
164 static int do_dwmci_init(struct dwmci_host *host)
165 {
166 	int index, flag, err;
167 
168 	index = host->dev_index;
169 
170 	flag = host->buswidth == 8 ? PINMUX_FLAG_8BIT_MODE : PINMUX_FLAG_NONE;
171 	err = exynos_pinmux_config(host->dev_id, flag);
172 	if (err) {
173 		printf("DWMMC%d not configure\n", index);
174 		return err;
175 	}
176 
177 	return exynos_dwmci_core_init(host, index);
178 }
179 
180 static int exynos_dwmci_get_config(const void *blob, int node,
181 					struct dwmci_host *host)
182 {
183 	int err = 0;
184 	u32 base, timing[3];
185 	struct dwmci_exynos_priv_data *priv;
186 
187 	priv = malloc(sizeof(struct dwmci_exynos_priv_data));
188 	if (!priv) {
189 		error("dwmci_exynos_priv_data malloc fail!\n");
190 		return -ENOMEM;
191 	}
192 
193 	/* Extract device id for each mmc channel */
194 	host->dev_id = pinmux_decode_periph_id(blob, node);
195 
196 	host->dev_index = fdtdec_get_int(blob, node, "index", host->dev_id);
197 	if (host->dev_index == host->dev_id)
198 		host->dev_index = host->dev_id - PERIPH_ID_SDMMC0;
199 
200 	/* Get the bus width from the device node */
201 	host->buswidth = fdtdec_get_int(blob, node, "samsung,bus-width", 0);
202 	if (host->buswidth <= 0) {
203 		printf("DWMMC%d: Can't get bus-width\n", host->dev_index);
204 		return -EINVAL;
205 	}
206 
207 	/* Set the base address from the device node */
208 	base = fdtdec_get_addr(blob, node, "reg");
209 	if (!base) {
210 		printf("DWMMC%d: Can't get base address\n", host->dev_index);
211 		return -EINVAL;
212 	}
213 	host->ioaddr = (void *)base;
214 
215 	/* Extract the timing info from the node */
216 	err =  fdtdec_get_int_array(blob, node, "samsung,timing", timing, 3);
217 	if (err) {
218 		printf("DWMMC%d: Can't get sdr-timings for devider\n",
219 				host->dev_index);
220 		return -EINVAL;
221 	}
222 
223 	priv->sdr_timing = (DWMCI_SET_SAMPLE_CLK(timing[0]) |
224 			DWMCI_SET_DRV_CLK(timing[1]) |
225 			DWMCI_SET_DIV_RATIO(timing[2]));
226 
227 	/* sdr_timing didn't assigned anything, use the default value */
228 	if (!priv->sdr_timing) {
229 		if (host->dev_index == 0)
230 			priv->sdr_timing = DWMMC_MMC0_SDR_TIMING_VAL;
231 		else if (host->dev_index == 2)
232 			priv->sdr_timing = DWMMC_MMC2_SDR_TIMING_VAL;
233 	}
234 
235 	host->fifoth_val = fdtdec_get_int(blob, node, "fifoth_val", 0);
236 	host->bus_hz = fdtdec_get_int(blob, node, "bus_hz", 0);
237 	host->div = fdtdec_get_int(blob, node, "div", 0);
238 
239 	host->priv = priv;
240 
241 	return 0;
242 }
243 
244 static int exynos_dwmci_process_node(const void *blob,
245 					int node_list[], int count)
246 {
247 	struct dwmci_host *host;
248 	int i, node, err;
249 
250 	for (i = 0; i < count; i++) {
251 		node = node_list[i];
252 		if (node <= 0)
253 			continue;
254 		host = &dwmci_host[i];
255 		err = exynos_dwmci_get_config(blob, node, host);
256 		if (err) {
257 			printf("%s: failed to decode dev %d\n", __func__, i);
258 			return err;
259 		}
260 
261 		do_dwmci_init(host);
262 	}
263 	return 0;
264 }
265 
266 int exynos_dwmmc_init(const void *blob)
267 {
268 	int compat_id;
269 	int node_list[DWMMC_MAX_CH_NUM];
270 	int boot_dev_node;
271 	int err = 0, count;
272 
273 	compat_id = COMPAT_SAMSUNG_EXYNOS_DWMMC;
274 
275 	count = fdtdec_find_aliases_for_id(blob, "mmc",
276 				compat_id, node_list, DWMMC_MAX_CH_NUM);
277 
278 	/* For DWMMC always set boot device as mmc 0 */
279 	if (count >= 3 && get_boot_mode() == BOOT_MODE_SD) {
280 		boot_dev_node = node_list[2];
281 		node_list[2] = node_list[0];
282 		node_list[0] = boot_dev_node;
283 	}
284 
285 	err = exynos_dwmci_process_node(blob, node_list, count);
286 
287 	return err;
288 }
289 #endif
290