xref: /openbmc/u-boot/drivers/mmc/socfpga_dw_mmc.c (revision fea7f3aa)
1 /*
2  * (C) Copyright 2013 Altera Corporation <www.altera.com>
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <common.h>
8 #include <malloc.h>
9 #include <fdtdec.h>
10 #include <libfdt.h>
11 #include <dwmmc.h>
12 #include <errno.h>
13 #include <asm/arch/dwmmc.h>
14 #include <asm/arch/clock_manager.h>
15 #include <asm/arch/system_manager.h>
16 
17 static const struct socfpga_clock_manager *clock_manager_base =
18 		(void *)SOCFPGA_CLKMGR_ADDRESS;
19 static const struct socfpga_system_manager *system_manager_base =
20 		(void *)SOCFPGA_SYSMGR_ADDRESS;
21 
22 static void socfpga_dwmci_clksel(struct dwmci_host *host)
23 {
24 	unsigned int drvsel;
25 	unsigned int smplsel;
26 
27 	/* Disable SDMMC clock. */
28 	clrbits_le32(&clock_manager_base->per_pll.en,
29 		CLKMGR_PERPLLGRP_EN_SDMMCCLK_MASK);
30 
31 	/* Configures drv_sel and smpl_sel */
32 	drvsel = CONFIG_SOCFPGA_DWMMC_DRVSEL;
33 	smplsel = CONFIG_SOCFPGA_DWMMC_SMPSEL;
34 
35 	debug("%s: drvsel %d smplsel %d\n", __func__, drvsel, smplsel);
36 	writel(SYSMGR_SDMMC_CTRL_SET(smplsel, drvsel),
37 		&system_manager_base->sdmmcgrp_ctrl);
38 
39 	debug("%s: SYSMGR_SDMMCGRP_CTRL_REG = 0x%x\n", __func__,
40 		readl(&system_manager_base->sdmmcgrp_ctrl));
41 
42 	/* Enable SDMMC clock */
43 	setbits_le32(&clock_manager_base->per_pll.en,
44 		CLKMGR_PERPLLGRP_EN_SDMMCCLK_MASK);
45 }
46 
47 static int socfpga_dwmci_of_probe(const void *blob, int node, const int idx)
48 {
49 	/* FIXME: probe from DT eventually too/ */
50 	const unsigned long clk = cm_get_mmc_controller_clk_hz();
51 
52 	struct dwmci_host *host;
53 	fdt_addr_t reg_base;
54 	int bus_width, fifo_depth;
55 
56 	if (clk == 0) {
57 		printf("DWMMC%d: MMC clock is zero!", idx);
58 		return -EINVAL;
59 	}
60 
61 	/* Get the register address from the device node */
62 	reg_base = fdtdec_get_addr(blob, node, "reg");
63 	if (!reg_base) {
64 		printf("DWMMC%d: Can't get base address\n", idx);
65 		return -EINVAL;
66 	}
67 
68 	/* Get the bus width from the device node */
69 	bus_width = fdtdec_get_int(blob, node, "bus-width", 0);
70 	if (bus_width <= 0) {
71 		printf("DWMMC%d: Can't get bus-width\n", idx);
72 		return -EINVAL;
73 	}
74 
75 	fifo_depth = fdtdec_get_int(blob, node, "fifo-depth", 0);
76 	if (fifo_depth < 0) {
77 		printf("DWMMC%d: Can't get FIFO depth\n", idx);
78 		return -EINVAL;
79 	}
80 
81 	/* Allocate the host */
82 	host = calloc(1, sizeof(*host));
83 	if (!host)
84 		return -ENOMEM;
85 
86 	host->name = "SOCFPGA DWMMC";
87 	host->ioaddr = (void *)reg_base;
88 	host->buswidth = bus_width;
89 	host->clksel = socfpga_dwmci_clksel;
90 	host->dev_index = idx;
91 	/* Fixed clock divide by 4 which due to the SDMMC wrapper */
92 	host->bus_hz = clk;
93 	host->fifoth_val = MSIZE(0x2) |
94 		RX_WMARK(fifo_depth / 2 - 1) | TX_WMARK(fifo_depth / 2);
95 
96 	return add_dwmci(host, host->bus_hz, 400000);
97 }
98 
99 static int socfpga_dwmci_process_node(const void *blob, int nodes[],
100 				      int count)
101 {
102 	int i, node, ret;
103 
104 	for (i = 0; i < count; i++) {
105 		node = nodes[i];
106 		if (node <= 0)
107 			continue;
108 
109 		ret = socfpga_dwmci_of_probe(blob, node, i);
110 		if (ret) {
111 			printf("%s: failed to decode dev %d\n", __func__, i);
112 			return ret;
113 		}
114 	}
115 	return 0;
116 }
117 
118 int socfpga_dwmmc_init(const void *blob)
119 {
120 	int nodes[2];	/* Max. two controllers. */
121 	int ret, count;
122 
123 	count = fdtdec_find_aliases_for_id(blob, "mmc",
124 					   COMPAT_ALTERA_SOCFPGA_DWMMC,
125 					   nodes, ARRAY_SIZE(nodes));
126 
127 	ret = socfpga_dwmci_process_node(blob, nodes, count);
128 
129 	return ret;
130 }
131