xref: /openbmc/linux/drivers/mfd/vexpress-sysreg.c (revision 82e6fdd6)
1 /*
2  * This program is free software; you can redistribute it and/or modify
3  * it under the terms of the GNU General Public License version 2 as
4  * published by the Free Software Foundation.
5  *
6  * This program is distributed in the hope that it will be useful,
7  * but WITHOUT ANY WARRANTY; without even the implied warranty of
8  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
9  * GNU General Public License for more details.
10  *
11  * Copyright (C) 2012 ARM Limited
12  */
13 
14 #include <linux/gpio/driver.h>
15 #include <linux/err.h>
16 #include <linux/io.h>
17 #include <linux/mfd/core.h>
18 #include <linux/of_address.h>
19 #include <linux/of_platform.h>
20 #include <linux/platform_data/syscon.h>
21 #include <linux/platform_device.h>
22 #include <linux/slab.h>
23 #include <linux/stat.h>
24 #include <linux/vexpress.h>
25 
26 #define SYS_ID			0x000
27 #define SYS_SW			0x004
28 #define SYS_LED			0x008
29 #define SYS_100HZ		0x024
30 #define SYS_FLAGSSET		0x030
31 #define SYS_FLAGSCLR		0x034
32 #define SYS_NVFLAGS		0x038
33 #define SYS_NVFLAGSSET		0x038
34 #define SYS_NVFLAGSCLR		0x03c
35 #define SYS_MCI			0x048
36 #define SYS_FLASH		0x04c
37 #define SYS_CFGSW		0x058
38 #define SYS_24MHZ		0x05c
39 #define SYS_MISC		0x060
40 #define SYS_DMA			0x064
41 #define SYS_PROCID0		0x084
42 #define SYS_PROCID1		0x088
43 #define SYS_CFGDATA		0x0a0
44 #define SYS_CFGCTRL		0x0a4
45 #define SYS_CFGSTAT		0x0a8
46 
47 #define SYS_HBI_MASK		0xfff
48 #define SYS_PROCIDx_HBI_SHIFT	0
49 
50 #define SYS_MISC_MASTERSITE	(1 << 14)
51 
52 void vexpress_flags_set(u32 data)
53 {
54 	static void __iomem *base;
55 
56 	if (!base) {
57 		struct device_node *node = of_find_compatible_node(NULL, NULL,
58 				"arm,vexpress-sysreg");
59 
60 		base = of_iomap(node, 0);
61 	}
62 
63 	if (WARN_ON(!base))
64 		return;
65 
66 	writel(~0, base + SYS_FLAGSCLR);
67 	writel(data, base + SYS_FLAGSSET);
68 }
69 
70 /* The sysreg block is just a random collection of various functions... */
71 
72 static struct syscon_platform_data vexpress_sysreg_sys_id_pdata = {
73 	.label = "sys_id",
74 };
75 
76 static struct bgpio_pdata vexpress_sysreg_sys_led_pdata = {
77 	.label = "sys_led",
78 	.base = -1,
79 	.ngpio = 8,
80 };
81 
82 static struct bgpio_pdata vexpress_sysreg_sys_mci_pdata = {
83 	.label = "sys_mci",
84 	.base = -1,
85 	.ngpio = 2,
86 };
87 
88 static struct bgpio_pdata vexpress_sysreg_sys_flash_pdata = {
89 	.label = "sys_flash",
90 	.base = -1,
91 	.ngpio = 1,
92 };
93 
94 static struct syscon_platform_data vexpress_sysreg_sys_misc_pdata = {
95 	.label = "sys_misc",
96 };
97 
98 static struct syscon_platform_data vexpress_sysreg_sys_procid_pdata = {
99 	.label = "sys_procid",
100 };
101 
102 static struct mfd_cell vexpress_sysreg_cells[] = {
103 	{
104 		.name = "syscon",
105 		.num_resources = 1,
106 		.resources = (struct resource []) {
107 			DEFINE_RES_MEM(SYS_ID, 0x4),
108 		},
109 		.platform_data = &vexpress_sysreg_sys_id_pdata,
110 		.pdata_size = sizeof(vexpress_sysreg_sys_id_pdata),
111 	}, {
112 		.name = "basic-mmio-gpio",
113 		.of_compatible = "arm,vexpress-sysreg,sys_led",
114 		.num_resources = 1,
115 		.resources = (struct resource []) {
116 			DEFINE_RES_MEM_NAMED(SYS_LED, 0x4, "dat"),
117 		},
118 		.platform_data = &vexpress_sysreg_sys_led_pdata,
119 		.pdata_size = sizeof(vexpress_sysreg_sys_led_pdata),
120 	}, {
121 		.name = "basic-mmio-gpio",
122 		.of_compatible = "arm,vexpress-sysreg,sys_mci",
123 		.num_resources = 1,
124 		.resources = (struct resource []) {
125 			DEFINE_RES_MEM_NAMED(SYS_MCI, 0x4, "dat"),
126 		},
127 		.platform_data = &vexpress_sysreg_sys_mci_pdata,
128 		.pdata_size = sizeof(vexpress_sysreg_sys_mci_pdata),
129 	}, {
130 		.name = "basic-mmio-gpio",
131 		.of_compatible = "arm,vexpress-sysreg,sys_flash",
132 		.num_resources = 1,
133 		.resources = (struct resource []) {
134 			DEFINE_RES_MEM_NAMED(SYS_FLASH, 0x4, "dat"),
135 		},
136 		.platform_data = &vexpress_sysreg_sys_flash_pdata,
137 		.pdata_size = sizeof(vexpress_sysreg_sys_flash_pdata),
138 	}, {
139 		.name = "syscon",
140 		.num_resources = 1,
141 		.resources = (struct resource []) {
142 			DEFINE_RES_MEM(SYS_MISC, 0x4),
143 		},
144 		.platform_data = &vexpress_sysreg_sys_misc_pdata,
145 		.pdata_size = sizeof(vexpress_sysreg_sys_misc_pdata),
146 	}, {
147 		.name = "syscon",
148 		.num_resources = 1,
149 		.resources = (struct resource []) {
150 			DEFINE_RES_MEM(SYS_PROCID0, 0x8),
151 		},
152 		.platform_data = &vexpress_sysreg_sys_procid_pdata,
153 		.pdata_size = sizeof(vexpress_sysreg_sys_procid_pdata),
154 	}, {
155 		.name = "vexpress-syscfg",
156 		.num_resources = 1,
157 		.resources = (struct resource []) {
158 			DEFINE_RES_MEM(SYS_CFGDATA, 0xc),
159 		},
160 	}
161 };
162 
163 static int vexpress_sysreg_probe(struct platform_device *pdev)
164 {
165 	struct resource *mem;
166 	void __iomem *base;
167 	struct gpio_chip *mmc_gpio_chip;
168 	int master;
169 	u32 dt_hbi;
170 
171 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
172 	if (!mem)
173 		return -EINVAL;
174 
175 	base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
176 	if (!base)
177 		return -ENOMEM;
178 
179 	master = readl(base + SYS_MISC) & SYS_MISC_MASTERSITE ?
180 			VEXPRESS_SITE_DB2 : VEXPRESS_SITE_DB1;
181 	vexpress_config_set_master(master);
182 
183 	/* Confirm board type against DT property, if available */
184 	if (of_property_read_u32(of_root, "arm,hbi", &dt_hbi) == 0) {
185 		u32 id = readl(base + (master == VEXPRESS_SITE_DB1 ?
186 				 SYS_PROCID0 : SYS_PROCID1));
187 		u32 hbi = (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
188 
189 		if (WARN_ON(dt_hbi != hbi))
190 			dev_warn(&pdev->dev, "DT HBI (%x) is not matching hardware (%x)!\n",
191 					dt_hbi, hbi);
192 	}
193 
194 	/*
195 	 * Duplicated SYS_MCI pseudo-GPIO controller for compatibility with
196 	 * older trees using sysreg node for MMC control lines.
197 	 */
198 	mmc_gpio_chip = devm_kzalloc(&pdev->dev, sizeof(*mmc_gpio_chip),
199 			GFP_KERNEL);
200 	if (!mmc_gpio_chip)
201 		return -ENOMEM;
202 	bgpio_init(mmc_gpio_chip, &pdev->dev, 0x4, base + SYS_MCI,
203 			NULL, NULL, NULL, NULL, 0);
204 	mmc_gpio_chip->ngpio = 2;
205 	gpiochip_add_data(mmc_gpio_chip, NULL);
206 
207 	return mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
208 			vexpress_sysreg_cells,
209 			ARRAY_SIZE(vexpress_sysreg_cells), mem, 0, NULL);
210 }
211 
212 static const struct of_device_id vexpress_sysreg_match[] = {
213 	{ .compatible = "arm,vexpress-sysreg", },
214 	{},
215 };
216 
217 static struct platform_driver vexpress_sysreg_driver = {
218 	.driver = {
219 		.name = "vexpress-sysreg",
220 		.of_match_table = vexpress_sysreg_match,
221 	},
222 	.probe = vexpress_sysreg_probe,
223 };
224 
225 static int __init vexpress_sysreg_init(void)
226 {
227 	struct device_node *node;
228 
229 	/* Need the sysreg early, before any other device... */
230 	for_each_matching_node(node, vexpress_sysreg_match)
231 		of_platform_device_create(node, NULL, NULL);
232 
233 	return platform_driver_register(&vexpress_sysreg_driver);
234 }
235 core_initcall(vexpress_sysreg_init);
236