xref: /openbmc/u-boot/drivers/mmc/exynos_dw_mmc.c (revision 965de8b9)
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 
17 #define	DWMMC_MAX_CH_NUM		4
18 #define	DWMMC_MAX_FREQ			52000000
19 #define	DWMMC_MIN_FREQ			400000
20 #define	DWMMC_MMC0_CLKSEL_VAL		0x03030001
21 #define	DWMMC_MMC2_CLKSEL_VAL		0x03020001
22 
23 /*
24  * Function used as callback function to initialise the
25  * CLKSEL register for every mmc channel.
26  */
27 static void exynos_dwmci_clksel(struct dwmci_host *host)
28 {
29 	dwmci_writel(host, DWMCI_CLKSEL, host->clksel_val);
30 }
31 
32 unsigned int exynos_dwmci_get_clk(int dev_index)
33 {
34 	return get_mmc_clk(dev_index);
35 }
36 
37 static void exynos_dwmci_board_init(struct dwmci_host *host)
38 {
39 	if (host->quirks & DWMCI_QUIRK_DISABLE_SMU) {
40 		dwmci_writel(host, EMMCP_MPSBEGIN0, 0);
41 		dwmci_writel(host, EMMCP_SEND0, 0);
42 		dwmci_writel(host, EMMCP_CTRL0,
43 			     MPSCTRL_SECURE_READ_BIT |
44 			     MPSCTRL_SECURE_WRITE_BIT |
45 			     MPSCTRL_NON_SECURE_READ_BIT |
46 			     MPSCTRL_NON_SECURE_WRITE_BIT | MPSCTRL_VALID);
47 	}
48 }
49 
50 /*
51  * This function adds the mmc channel to be registered with mmc core.
52  * index -	mmc channel number.
53  * regbase -	register base address of mmc channel specified in 'index'.
54  * bus_width -	operating bus width of mmc channel specified in 'index'.
55  * clksel -	value to be written into CLKSEL register in case of FDT.
56  *		NULL in case od non-FDT.
57  */
58 int exynos_dwmci_add_port(int index, u32 regbase, int bus_width, u32 clksel)
59 {
60 	struct dwmci_host *host = NULL;
61 	unsigned int div;
62 	unsigned long freq, sclk;
63 	host = malloc(sizeof(struct dwmci_host));
64 	if (!host) {
65 		printf("dwmci_host malloc fail!\n");
66 		return 1;
67 	}
68 	/* request mmc clock vlaue of 52MHz.  */
69 	freq = 52000000;
70 	sclk = get_mmc_clk(index);
71 	div = DIV_ROUND_UP(sclk, freq);
72 	/* set the clock divisor for mmc */
73 	set_mmc_clk(index, div);
74 
75 	host->name = "EXYNOS DWMMC";
76 	host->ioaddr = (void *)regbase;
77 	host->buswidth = bus_width;
78 #ifdef CONFIG_EXYNOS5420
79 	host->quirks = DWMCI_QUIRK_DISABLE_SMU;
80 #endif
81 	host->board_init = exynos_dwmci_board_init;
82 
83 	if (clksel) {
84 		host->clksel_val = clksel;
85 	} else {
86 		if (0 == index)
87 			host->clksel_val = DWMMC_MMC0_CLKSEL_VAL;
88 		if (2 == index)
89 			host->clksel_val = DWMMC_MMC2_CLKSEL_VAL;
90 	}
91 
92 	host->clksel = exynos_dwmci_clksel;
93 	host->dev_index = index;
94 	host->get_mmc_clk = exynos_dwmci_get_clk;
95 	/* Add the mmc channel to be registered with mmc core */
96 	if (add_dwmci(host, DWMMC_MAX_FREQ, DWMMC_MIN_FREQ)) {
97 		debug("dwmmc%d registration failed\n", index);
98 		return -1;
99 	}
100 	return 0;
101 }
102 
103 #ifdef CONFIG_OF_CONTROL
104 int exynos_dwmmc_init(const void *blob)
105 {
106 	int index, bus_width;
107 	int node_list[DWMMC_MAX_CH_NUM];
108 	int err = 0, dev_id, flag, count, i;
109 	u32 clksel_val, base, timing[3];
110 
111 	count = fdtdec_find_aliases_for_id(blob, "mmc",
112 				COMPAT_SAMSUNG_EXYNOS5_DWMMC, node_list,
113 				DWMMC_MAX_CH_NUM);
114 
115 	for (i = 0; i < count; i++) {
116 		int node = node_list[i];
117 
118 		if (node <= 0)
119 			continue;
120 
121 		/* Extract device id for each mmc channel */
122 		dev_id = pinmux_decode_periph_id(blob, node);
123 
124 		/* Get the bus width from the device node */
125 		bus_width = fdtdec_get_int(blob, node, "samsung,bus-width", 0);
126 		if (bus_width <= 0) {
127 			debug("DWMMC: Can't get bus-width\n");
128 			return -1;
129 		}
130 		if (8 == bus_width)
131 			flag = PINMUX_FLAG_8BIT_MODE;
132 		else
133 			flag = PINMUX_FLAG_NONE;
134 
135 		/* config pinmux for each mmc channel */
136 		err = exynos_pinmux_config(dev_id, flag);
137 		if (err) {
138 			debug("DWMMC not configured\n");
139 			return err;
140 		}
141 
142 		index = dev_id - PERIPH_ID_SDMMC0;
143 
144 		/* Get the base address from the device node */
145 		base = fdtdec_get_addr(blob, node, "reg");
146 		if (!base) {
147 			debug("DWMMC: Can't get base address\n");
148 			return -1;
149 		}
150 		/* Extract the timing info from the node */
151 		err = fdtdec_get_int_array(blob, node, "samsung,timing",
152 					timing, 3);
153 		if (err) {
154 			debug("Can't get sdr-timings for divider\n");
155 			return -1;
156 		}
157 
158 		clksel_val = (DWMCI_SET_SAMPLE_CLK(timing[0]) |
159 				DWMCI_SET_DRV_CLK(timing[1]) |
160 				DWMCI_SET_DIV_RATIO(timing[2]));
161 		/* Initialise each mmc channel */
162 		err = exynos_dwmci_add_port(index, base, bus_width, clksel_val);
163 		if (err)
164 			debug("dwmmc Channel-%d init failed\n", index);
165 	}
166 	return 0;
167 }
168 #endif
169