xref: /openbmc/u-boot/drivers/ram/bmips_ram.c (revision fbe44dd1)
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 <errno.h>
13 #include <ram.h>
14 #include <asm/io.h>
15 #include <dm/device.h>
16 
17 #define MEMC_CFG_REG		0x4
18 #define MEMC_CFG_32B_SHIFT	1
19 #define MEMC_CFG_32B_MASK	(1 << MEMC_CFG_32B_SHIFT)
20 #define MEMC_CFG_COL_SHIFT	3
21 #define MEMC_CFG_COL_MASK	(0x3 << MEMC_CFG_COL_SHIFT)
22 #define MEMC_CFG_ROW_SHIFT	6
23 #define MEMC_CFG_ROW_MASK	(0x3 << MEMC_CFG_ROW_SHIFT)
24 
25 #define DDR_CSEND_REG		0x8
26 
27 struct bmips_ram_priv;
28 
29 struct bmips_ram_hw {
30 	ulong (*get_ram_size)(struct bmips_ram_priv *);
31 };
32 
33 struct bmips_ram_priv {
34 	void __iomem *regs;
35 	const struct bmips_ram_hw *hw;
36 };
37 
38 static ulong bcm6328_get_ram_size(struct bmips_ram_priv *priv)
39 {
40 	return readl_be(priv->regs + DDR_CSEND_REG) << 24;
41 }
42 
43 static ulong bcm6358_get_ram_size(struct bmips_ram_priv *priv)
44 {
45 	unsigned int cols = 0, rows = 0, is_32bits = 0, banks = 0;
46 	u32 val;
47 
48 	val = readl_be(priv->regs + MEMC_CFG_REG);
49 	rows = (val & MEMC_CFG_ROW_MASK) >> MEMC_CFG_ROW_SHIFT;
50 	cols = (val & MEMC_CFG_COL_MASK) >> MEMC_CFG_COL_SHIFT;
51 	is_32bits = (val & MEMC_CFG_32B_MASK) ? 0 : 1;
52 	banks = 2;
53 
54 	/* 0 => 11 address bits ... 2 => 13 address bits */
55 	rows += 11;
56 
57 	/* 0 => 8 address bits ... 2 => 10 address bits */
58 	cols += 8;
59 
60 	return 1 << (cols + rows + (is_32bits + 1) + banks);
61 }
62 
63 static int bmips_ram_get_info(struct udevice *dev, struct ram_info *info)
64 {
65 	struct bmips_ram_priv *priv = dev_get_priv(dev);
66 	const struct bmips_ram_hw *hw = priv->hw;
67 
68 	info->base = 0x80000000;
69 	info->size = hw->get_ram_size(priv);
70 
71 	return 0;
72 }
73 
74 static const struct ram_ops bmips_ram_ops = {
75 	.get_info = bmips_ram_get_info,
76 };
77 
78 static const struct bmips_ram_hw bmips_ram_bcm6328 = {
79 	.get_ram_size = bcm6328_get_ram_size,
80 };
81 
82 static const struct bmips_ram_hw bmips_ram_bcm6358 = {
83 	.get_ram_size = bcm6358_get_ram_size,
84 };
85 
86 static const struct udevice_id bmips_ram_ids[] = {
87 	{
88 		.compatible = "brcm,bcm6328-mc",
89 		.data = (ulong)&bmips_ram_bcm6328,
90 	}, {
91 		.compatible = "brcm,bcm6358-mc",
92 		.data = (ulong)&bmips_ram_bcm6358,
93 	}, { /* sentinel */ }
94 };
95 
96 static int bmips_ram_probe(struct udevice *dev)
97 {
98 	struct bmips_ram_priv *priv = dev_get_priv(dev);
99 	const struct bmips_ram_hw *hw =
100 		(const struct bmips_ram_hw *)dev_get_driver_data(dev);
101 	fdt_addr_t addr;
102 	fdt_size_t size;
103 
104 	addr = dev_get_addr_size_index(dev, 0, &size);
105 	if (addr == FDT_ADDR_T_NONE)
106 		return -EINVAL;
107 
108 	priv->regs = ioremap(addr, size);
109 	priv->hw = hw;
110 
111 	return 0;
112 }
113 
114 U_BOOT_DRIVER(bmips_ram) = {
115 	.name = "bmips-mc",
116 	.id = UCLASS_RAM,
117 	.of_match = bmips_ram_ids,
118 	.probe = bmips_ram_probe,
119 	.priv_auto_alloc_size = sizeof(struct bmips_ram_priv),
120 	.ops = &bmips_ram_ops,
121 	.flags = DM_FLAG_PRE_RELOC,
122 };
123