xref: /openbmc/u-boot/drivers/mmc/exynos_dw_mmc.c (revision 5ff10aa7)
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/gpio.h>
17 #include <asm-generic/errno.h>
18 
19 #define	DWMMC_MAX_CH_NUM		4
20 #define	DWMMC_MAX_FREQ			52000000
21 #define	DWMMC_MIN_FREQ			400000
22 #define	DWMMC_MMC0_CLKSEL_VAL		0x03030001
23 #define	DWMMC_MMC2_CLKSEL_VAL		0x03020001
24 
25 /*
26  * Function used as callback function to initialise the
27  * CLKSEL register for every mmc channel.
28  */
29 static void exynos_dwmci_clksel(struct dwmci_host *host)
30 {
31 	dwmci_writel(host, DWMCI_CLKSEL, host->clksel_val);
32 }
33 
34 unsigned int exynos_dwmci_get_clk(struct dwmci_host *host)
35 {
36 	unsigned long sclk;
37 	int8_t clk_div;
38 
39 	/*
40 	 * Since SDCLKIN is divided inside controller by the DIVRATIO
41 	 * value set in the CLKSEL register, we need to use the same output
42 	 * clock value to calculate the CLKDIV value.
43 	 * as per user manual:cclk_in = SDCLKIN / (DIVRATIO + 1)
44 	 */
45 	clk_div = ((dwmci_readl(host, DWMCI_CLKSEL) >> DWMCI_DIVRATIO_BIT)
46 			& DWMCI_DIVRATIO_MASK) + 1;
47 	sclk = get_mmc_clk(host->dev_index);
48 
49 	/*
50 	 * Assume to know divider value.
51 	 * When clock unit is broken, need to set "host->div"
52 	 */
53 	return sclk / clk_div / (host->div + 1);
54 }
55 
56 static void exynos_dwmci_board_init(struct dwmci_host *host)
57 {
58 	if (host->quirks & DWMCI_QUIRK_DISABLE_SMU) {
59 		dwmci_writel(host, EMMCP_MPSBEGIN0, 0);
60 		dwmci_writel(host, EMMCP_SEND0, 0);
61 		dwmci_writel(host, EMMCP_CTRL0,
62 			     MPSCTRL_SECURE_READ_BIT |
63 			     MPSCTRL_SECURE_WRITE_BIT |
64 			     MPSCTRL_NON_SECURE_READ_BIT |
65 			     MPSCTRL_NON_SECURE_WRITE_BIT | MPSCTRL_VALID);
66 	}
67 }
68 
69 static int exynos_dwmci_core_init(struct dwmci_host *host, int index)
70 {
71 	unsigned int div;
72 	unsigned long freq, sclk;
73 
74 	if (host->bus_hz)
75 		freq = host->bus_hz;
76 	else
77 		freq = DWMMC_MAX_FREQ;
78 
79 	/* request mmc clock vlaue of 52MHz.  */
80 	sclk = get_mmc_clk(index);
81 	div = DIV_ROUND_UP(sclk, freq);
82 	/* set the clock divisor for mmc */
83 	set_mmc_clk(index, div);
84 
85 	host->name = "EXYNOS DWMMC";
86 #ifdef CONFIG_EXYNOS5420
87 	host->quirks = DWMCI_QUIRK_DISABLE_SMU;
88 #endif
89 	host->board_init = exynos_dwmci_board_init;
90 
91 	if (!host->clksel_val) {
92 		if (index == 0)
93 			host->clksel_val = DWMMC_MMC0_CLKSEL_VAL;
94 		else if (index == 2)
95 			host->clksel_val = DWMMC_MMC2_CLKSEL_VAL;
96 	}
97 
98 	host->caps = MMC_MODE_DDR_52MHz;
99 	host->clksel = exynos_dwmci_clksel;
100 	host->dev_index = index;
101 	host->get_mmc_clk = exynos_dwmci_get_clk;
102 	/* Add the mmc channel to be registered with mmc core */
103 	if (add_dwmci(host, DWMMC_MAX_FREQ, DWMMC_MIN_FREQ)) {
104 		debug("dwmmc%d registration failed\n", index);
105 		return -1;
106 	}
107 	return 0;
108 }
109 
110 /*
111  * This function adds the mmc channel to be registered with mmc core.
112  * index -	mmc channel number.
113  * regbase -	register base address of mmc channel specified in 'index'.
114  * bus_width -	operating bus width of mmc channel specified in 'index'.
115  * clksel -	value to be written into CLKSEL register in case of FDT.
116  *		NULL in case od non-FDT.
117  */
118 int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32 clksel)
119 {
120 	struct dwmci_host *host = NULL;
121 
122 	host = malloc(sizeof(struct dwmci_host));
123 	if (!host) {
124 		error("dwmci_host malloc fail!\n");
125 		return -ENOMEM;
126 	}
127 
128 	host->ioaddr = (void *)regbase;
129 	host->buswidth = bus_width;
130 
131 	if (clksel)
132 		host->clksel_val = clksel;
133 
134 	return exynos_dwmci_core_init(host, index);
135 }
136 
137 #ifdef CONFIG_OF_CONTROL
138 static struct dwmci_host dwmci_host[DWMMC_MAX_CH_NUM];
139 
140 static int do_dwmci_init(struct dwmci_host *host)
141 {
142 	int index, flag, err;
143 
144 	index = host->dev_index;
145 
146 	flag = host->buswidth == 8 ? PINMUX_FLAG_8BIT_MODE : PINMUX_FLAG_NONE;
147 	err = exynos_pinmux_config(host->dev_id, flag);
148 	if (err) {
149 		debug("DWMMC not configure\n");
150 		return err;
151 	}
152 
153 	return exynos_dwmci_core_init(host, index);
154 }
155 
156 static int exynos_dwmci_get_config(const void *blob, int node,
157 					struct dwmci_host *host)
158 {
159 	int err = 0;
160 	u32 base, clksel_val, timing[3];
161 
162 	/* Extract device id for each mmc channel */
163 	host->dev_id = pinmux_decode_periph_id(blob, node);
164 
165 	/* Get the bus width from the device node */
166 	host->buswidth = fdtdec_get_int(blob, node, "samsung,bus-width", 0);
167 	if (host->buswidth <= 0) {
168 		debug("DWMMC: Can't get bus-width\n");
169 		return -EINVAL;
170 	}
171 
172 	host->dev_index = fdtdec_get_int(blob, node, "index", host->dev_id);
173 	if (host->dev_index == host->dev_id)
174 		host->dev_index = host->dev_id - PERIPH_ID_SDMMC0;
175 
176 	/* Set the base address from the device node */
177 	base = fdtdec_get_addr(blob, node, "reg");
178 	if (!base) {
179 		debug("DWMMC: Can't get base address\n");
180 		return -EINVAL;
181 	}
182 	host->ioaddr = (void *)base;
183 
184 	/* Extract the timing info from the node */
185 	err =  fdtdec_get_int_array(blob, node, "samsung,timing", timing, 3);
186 	if (err) {
187 		debug("Can't get sdr-timings for devider\n");
188 		return -EINVAL;
189 	}
190 
191 	clksel_val = (DWMCI_SET_SAMPLE_CLK(timing[0]) |
192 			DWMCI_SET_DRV_CLK(timing[1]) |
193 			DWMCI_SET_DIV_RATIO(timing[2]));
194 	if (clksel_val)
195 		host->clksel_val = clksel_val;
196 
197 	host->fifoth_val = fdtdec_get_int(blob, node, "fifoth_val", 0);
198 	host->bus_hz = fdtdec_get_int(blob, node, "bus_hz", 0);
199 	host->div = fdtdec_get_int(blob, node, "div", 0);
200 
201 	return 0;
202 }
203 
204 static int exynos_dwmci_process_node(const void *blob,
205 					int node_list[], int count)
206 {
207 	struct dwmci_host *host;
208 	int i, node, err;
209 
210 	for (i = 0; i < count; i++) {
211 		node = node_list[i];
212 		if (node <= 0)
213 			continue;
214 		host = &dwmci_host[i];
215 		err = exynos_dwmci_get_config(blob, node, host);
216 		if (err) {
217 			debug("%s: failed to decode dev %d\n", __func__, i);
218 			return err;
219 		}
220 
221 		do_dwmci_init(host);
222 	}
223 	return 0;
224 }
225 
226 int exynos_dwmmc_init(const void *blob)
227 {
228 	int compat_id;
229 	int node_list[DWMMC_MAX_CH_NUM];
230 	int err = 0, count;
231 
232 	compat_id = COMPAT_SAMSUNG_EXYNOS_DWMMC;
233 
234 	count = fdtdec_find_aliases_for_id(blob, "mmc",
235 				compat_id, node_list, DWMMC_MAX_CH_NUM);
236 	err = exynos_dwmci_process_node(blob, node_list, count);
237 
238 	return err;
239 }
240 #endif
241