xref: /openbmc/linux/drivers/mfd/vexpress-sysreg.c (revision 6c33a6f4)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  * Copyright (C) 2012 ARM Limited
5  */
6 
7 #include <linux/gpio/driver.h>
8 #include <linux/err.h>
9 #include <linux/io.h>
10 #include <linux/mfd/core.h>
11 #include <linux/of_address.h>
12 #include <linux/of_platform.h>
13 #include <linux/platform_data/syscon.h>
14 #include <linux/platform_device.h>
15 #include <linux/slab.h>
16 #include <linux/stat.h>
17 #include <linux/vexpress.h>
18 
19 #define SYS_ID			0x000
20 #define SYS_SW			0x004
21 #define SYS_LED			0x008
22 #define SYS_100HZ		0x024
23 #define SYS_FLAGSSET		0x030
24 #define SYS_FLAGSCLR		0x034
25 #define SYS_NVFLAGS		0x038
26 #define SYS_NVFLAGSSET		0x038
27 #define SYS_NVFLAGSCLR		0x03c
28 #define SYS_MCI			0x048
29 #define SYS_FLASH		0x04c
30 #define SYS_CFGSW		0x058
31 #define SYS_24MHZ		0x05c
32 #define SYS_MISC		0x060
33 #define SYS_DMA			0x064
34 #define SYS_PROCID0		0x084
35 #define SYS_PROCID1		0x088
36 #define SYS_CFGDATA		0x0a0
37 #define SYS_CFGCTRL		0x0a4
38 #define SYS_CFGSTAT		0x0a8
39 
40 #define SYS_HBI_MASK		0xfff
41 #define SYS_PROCIDx_HBI_SHIFT	0
42 
43 #define SYS_MISC_MASTERSITE	(1 << 14)
44 
45 void vexpress_flags_set(u32 data)
46 {
47 	static void __iomem *base;
48 
49 	if (!base) {
50 		struct device_node *node = of_find_compatible_node(NULL, NULL,
51 				"arm,vexpress-sysreg");
52 
53 		base = of_iomap(node, 0);
54 	}
55 
56 	if (WARN_ON(!base))
57 		return;
58 
59 	writel(~0, base + SYS_FLAGSCLR);
60 	writel(data, base + SYS_FLAGSSET);
61 }
62 
63 /* The sysreg block is just a random collection of various functions... */
64 
65 static struct syscon_platform_data vexpress_sysreg_sys_id_pdata = {
66 	.label = "sys_id",
67 };
68 
69 static struct bgpio_pdata vexpress_sysreg_sys_led_pdata = {
70 	.label = "sys_led",
71 	.base = -1,
72 	.ngpio = 8,
73 };
74 
75 static struct bgpio_pdata vexpress_sysreg_sys_mci_pdata = {
76 	.label = "sys_mci",
77 	.base = -1,
78 	.ngpio = 2,
79 };
80 
81 static struct bgpio_pdata vexpress_sysreg_sys_flash_pdata = {
82 	.label = "sys_flash",
83 	.base = -1,
84 	.ngpio = 1,
85 };
86 
87 static struct syscon_platform_data vexpress_sysreg_sys_misc_pdata = {
88 	.label = "sys_misc",
89 };
90 
91 static struct syscon_platform_data vexpress_sysreg_sys_procid_pdata = {
92 	.label = "sys_procid",
93 };
94 
95 static struct mfd_cell vexpress_sysreg_cells[] = {
96 	{
97 		.name = "syscon",
98 		.num_resources = 1,
99 		.resources = (struct resource []) {
100 			DEFINE_RES_MEM(SYS_ID, 0x4),
101 		},
102 		.platform_data = &vexpress_sysreg_sys_id_pdata,
103 		.pdata_size = sizeof(vexpress_sysreg_sys_id_pdata),
104 	}, {
105 		.name = "basic-mmio-gpio",
106 		.of_compatible = "arm,vexpress-sysreg,sys_led",
107 		.num_resources = 1,
108 		.resources = (struct resource []) {
109 			DEFINE_RES_MEM_NAMED(SYS_LED, 0x4, "dat"),
110 		},
111 		.platform_data = &vexpress_sysreg_sys_led_pdata,
112 		.pdata_size = sizeof(vexpress_sysreg_sys_led_pdata),
113 	}, {
114 		.name = "basic-mmio-gpio",
115 		.of_compatible = "arm,vexpress-sysreg,sys_mci",
116 		.num_resources = 1,
117 		.resources = (struct resource []) {
118 			DEFINE_RES_MEM_NAMED(SYS_MCI, 0x4, "dat"),
119 		},
120 		.platform_data = &vexpress_sysreg_sys_mci_pdata,
121 		.pdata_size = sizeof(vexpress_sysreg_sys_mci_pdata),
122 	}, {
123 		.name = "basic-mmio-gpio",
124 		.of_compatible = "arm,vexpress-sysreg,sys_flash",
125 		.num_resources = 1,
126 		.resources = (struct resource []) {
127 			DEFINE_RES_MEM_NAMED(SYS_FLASH, 0x4, "dat"),
128 		},
129 		.platform_data = &vexpress_sysreg_sys_flash_pdata,
130 		.pdata_size = sizeof(vexpress_sysreg_sys_flash_pdata),
131 	}, {
132 		.name = "syscon",
133 		.num_resources = 1,
134 		.resources = (struct resource []) {
135 			DEFINE_RES_MEM(SYS_MISC, 0x4),
136 		},
137 		.platform_data = &vexpress_sysreg_sys_misc_pdata,
138 		.pdata_size = sizeof(vexpress_sysreg_sys_misc_pdata),
139 	}, {
140 		.name = "syscon",
141 		.num_resources = 1,
142 		.resources = (struct resource []) {
143 			DEFINE_RES_MEM(SYS_PROCID0, 0x8),
144 		},
145 		.platform_data = &vexpress_sysreg_sys_procid_pdata,
146 		.pdata_size = sizeof(vexpress_sysreg_sys_procid_pdata),
147 	}, {
148 		.name = "vexpress-syscfg",
149 		.num_resources = 1,
150 		.resources = (struct resource []) {
151 			DEFINE_RES_MEM(SYS_CFGDATA, 0xc),
152 		},
153 	}
154 };
155 
156 static int vexpress_sysreg_probe(struct platform_device *pdev)
157 {
158 	struct resource *mem;
159 	void __iomem *base;
160 	struct gpio_chip *mmc_gpio_chip;
161 	int master;
162 	u32 dt_hbi;
163 
164 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
165 	if (!mem)
166 		return -EINVAL;
167 
168 	base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
169 	if (!base)
170 		return -ENOMEM;
171 
172 	master = readl(base + SYS_MISC) & SYS_MISC_MASTERSITE ?
173 			VEXPRESS_SITE_DB2 : VEXPRESS_SITE_DB1;
174 	vexpress_config_set_master(master);
175 
176 	/* Confirm board type against DT property, if available */
177 	if (of_property_read_u32(of_root, "arm,hbi", &dt_hbi) == 0) {
178 		u32 id = readl(base + (master == VEXPRESS_SITE_DB1 ?
179 				 SYS_PROCID0 : SYS_PROCID1));
180 		u32 hbi = (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
181 
182 		if (WARN_ON(dt_hbi != hbi))
183 			dev_warn(&pdev->dev, "DT HBI (%x) is not matching hardware (%x)!\n",
184 					dt_hbi, hbi);
185 	}
186 
187 	/*
188 	 * Duplicated SYS_MCI pseudo-GPIO controller for compatibility with
189 	 * older trees using sysreg node for MMC control lines.
190 	 */
191 	mmc_gpio_chip = devm_kzalloc(&pdev->dev, sizeof(*mmc_gpio_chip),
192 			GFP_KERNEL);
193 	if (!mmc_gpio_chip)
194 		return -ENOMEM;
195 	bgpio_init(mmc_gpio_chip, &pdev->dev, 0x4, base + SYS_MCI,
196 			NULL, NULL, NULL, NULL, 0);
197 	mmc_gpio_chip->ngpio = 2;
198 	gpiochip_add_data(mmc_gpio_chip, NULL);
199 
200 	return mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
201 			vexpress_sysreg_cells,
202 			ARRAY_SIZE(vexpress_sysreg_cells), mem, 0, NULL);
203 }
204 
205 static const struct of_device_id vexpress_sysreg_match[] = {
206 	{ .compatible = "arm,vexpress-sysreg", },
207 	{},
208 };
209 
210 static struct platform_driver vexpress_sysreg_driver = {
211 	.driver = {
212 		.name = "vexpress-sysreg",
213 		.of_match_table = vexpress_sysreg_match,
214 	},
215 	.probe = vexpress_sysreg_probe,
216 };
217 
218 static int __init vexpress_sysreg_init(void)
219 {
220 	struct device_node *node;
221 
222 	/* Need the sysreg early, before any other device... */
223 	for_each_matching_node(node, vexpress_sysreg_match)
224 		of_platform_device_create(node, NULL, NULL);
225 
226 	return platform_driver_register(&vexpress_sysreg_driver);
227 }
228 core_initcall(vexpress_sysreg_init);
229