xref: /openbmc/u-boot/drivers/ram/bmips_ram.c (revision 72719d2f)
1 /*
2  * Copyright (C) 2017 Álvaro Fernández Rojas <noltari@gmail.com>
3  *
4  * Derived from linux/arch/mips/bcm63xx/cpu.c:
5  *	Copyright (C) 2008 Maxime Bizon <mbizon@freebox.fr>
6  *	Copyright (C) 2009 Florian Fainelli <florian@openwrt.org>
7  *
8  * SPDX-License-Identifier:	GPL-2.0+
9  */
10 
11 #include <common.h>
12 #include <dm.h>
13 #include <errno.h>
14 #include <ram.h>
15 #include <asm/io.h>
16 
17 #define SDRAM_CFG_REG		0x0
18 #define SDRAM_CFG_COL_SHIFT	4
19 #define SDRAM_CFG_COL_MASK	(0x3 << SDRAM_CFG_COL_SHIFT)
20 #define SDRAM_CFG_ROW_SHIFT	6
21 #define SDRAM_CFG_ROW_MASK	(0x3 << SDRAM_CFG_ROW_SHIFT)
22 #define SDRAM_CFG_32B_SHIFT	10
23 #define SDRAM_CFG_32B_MASK	(1 << SDRAM_CFG_32B_SHIFT)
24 #define SDRAM_CFG_BANK_SHIFT	13
25 #define SDRAM_CFG_BANK_MASK	(1 << SDRAM_CFG_BANK_SHIFT)
26 
27 #define MEMC_CFG_REG		0x4
28 #define MEMC_CFG_32B_SHIFT	1
29 #define MEMC_CFG_32B_MASK	(1 << MEMC_CFG_32B_SHIFT)
30 #define MEMC_CFG_COL_SHIFT	3
31 #define MEMC_CFG_COL_MASK	(0x3 << MEMC_CFG_COL_SHIFT)
32 #define MEMC_CFG_ROW_SHIFT	6
33 #define MEMC_CFG_ROW_MASK	(0x3 << MEMC_CFG_ROW_SHIFT)
34 
35 #define DDR_CSEND_REG		0x8
36 
37 struct bmips_ram_priv;
38 
39 struct bmips_ram_hw {
40 	ulong (*get_ram_size)(struct bmips_ram_priv *);
41 };
42 
43 struct bmips_ram_priv {
44 	void __iomem *regs;
45 	const struct bmips_ram_hw *hw;
46 };
47 
48 static ulong bcm6328_get_ram_size(struct bmips_ram_priv *priv)
49 {
50 	return readl_be(priv->regs + DDR_CSEND_REG) << 24;
51 }
52 
53 static ulong bmips_dram_size(unsigned int cols, unsigned int rows,
54 			     unsigned int is_32b, unsigned int banks)
55 {
56 	rows += 11; /* 0 => 11 address bits ... 2 => 13 address bits */
57 	cols += 8; /* 0 => 8 address bits ... 2 => 10 address bits */
58 	is_32b += 1;
59 
60 	return 1 << (cols + rows + is_32b + banks);
61 }
62 
63 static ulong bcm6338_get_ram_size(struct bmips_ram_priv *priv)
64 {
65 	unsigned int cols = 0, rows = 0, is_32b = 0, banks = 0;
66 	u32 val;
67 
68 	val = readl_be(priv->regs + SDRAM_CFG_REG);
69 	rows = (val & SDRAM_CFG_ROW_MASK) >> SDRAM_CFG_ROW_SHIFT;
70 	cols = (val & SDRAM_CFG_COL_MASK) >> SDRAM_CFG_COL_SHIFT;
71 	is_32b = (val & SDRAM_CFG_32B_MASK) ? 1 : 0;
72 	banks = (val & SDRAM_CFG_BANK_MASK) ? 2 : 1;
73 
74 	return bmips_dram_size(cols, rows, is_32b, banks);
75 }
76 
77 static ulong bcm6358_get_ram_size(struct bmips_ram_priv *priv)
78 {
79 	unsigned int cols = 0, rows = 0, is_32b = 0;
80 	u32 val;
81 
82 	val = readl_be(priv->regs + MEMC_CFG_REG);
83 	rows = (val & MEMC_CFG_ROW_MASK) >> MEMC_CFG_ROW_SHIFT;
84 	cols = (val & MEMC_CFG_COL_MASK) >> MEMC_CFG_COL_SHIFT;
85 	is_32b = (val & MEMC_CFG_32B_MASK) ? 0 : 1;
86 
87 	return bmips_dram_size(cols, rows, is_32b, 2);
88 }
89 
90 static int bmips_ram_get_info(struct udevice *dev, struct ram_info *info)
91 {
92 	struct bmips_ram_priv *priv = dev_get_priv(dev);
93 	const struct bmips_ram_hw *hw = priv->hw;
94 
95 	info->base = 0x80000000;
96 	info->size = hw->get_ram_size(priv);
97 
98 	return 0;
99 }
100 
101 static const struct ram_ops bmips_ram_ops = {
102 	.get_info = bmips_ram_get_info,
103 };
104 
105 static const struct bmips_ram_hw bmips_ram_bcm6328 = {
106 	.get_ram_size = bcm6328_get_ram_size,
107 };
108 
109 static const struct bmips_ram_hw bmips_ram_bcm6338 = {
110 	.get_ram_size = bcm6338_get_ram_size,
111 };
112 
113 static const struct bmips_ram_hw bmips_ram_bcm6358 = {
114 	.get_ram_size = bcm6358_get_ram_size,
115 };
116 
117 static const struct udevice_id bmips_ram_ids[] = {
118 	{
119 		.compatible = "brcm,bcm6328-mc",
120 		.data = (ulong)&bmips_ram_bcm6328,
121 	}, {
122 		.compatible = "brcm,bcm6338-mc",
123 		.data = (ulong)&bmips_ram_bcm6338,
124 	}, {
125 		.compatible = "brcm,bcm6358-mc",
126 		.data = (ulong)&bmips_ram_bcm6358,
127 	}, { /* sentinel */ }
128 };
129 
130 static int bmips_ram_probe(struct udevice *dev)
131 {
132 	struct bmips_ram_priv *priv = dev_get_priv(dev);
133 	const struct bmips_ram_hw *hw =
134 		(const struct bmips_ram_hw *)dev_get_driver_data(dev);
135 	fdt_addr_t addr;
136 	fdt_size_t size;
137 
138 	addr = devfdt_get_addr_size_index(dev, 0, &size);
139 	if (addr == FDT_ADDR_T_NONE)
140 		return -EINVAL;
141 
142 	priv->regs = ioremap(addr, size);
143 	priv->hw = hw;
144 
145 	return 0;
146 }
147 
148 U_BOOT_DRIVER(bmips_ram) = {
149 	.name = "bmips-mc",
150 	.id = UCLASS_RAM,
151 	.of_match = bmips_ram_ids,
152 	.probe = bmips_ram_probe,
153 	.priv_auto_alloc_size = sizeof(struct bmips_ram_priv),
154 	.ops = &bmips_ram_ops,
155 	.flags = DM_FLAG_PRE_RELOC,
156 };
157