xref: /openbmc/linux/drivers/mfd/vexpress-sysreg.c (revision c819e2cf)
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/basic_mmio_gpio.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_MCI_CARDIN		(1 << 0)
51 #define SYS_MCI_WPROT		(1 << 1)
52 
53 #define SYS_MISC_MASTERSITE	(1 << 14)
54 
55 
56 static void __iomem *__vexpress_sysreg_base;
57 
58 static void __iomem *vexpress_sysreg_base(void)
59 {
60 	if (!__vexpress_sysreg_base) {
61 		struct device_node *node = of_find_compatible_node(NULL, NULL,
62 				"arm,vexpress-sysreg");
63 
64 		__vexpress_sysreg_base = of_iomap(node, 0);
65 	}
66 
67 	WARN_ON(!__vexpress_sysreg_base);
68 
69 	return __vexpress_sysreg_base;
70 }
71 
72 
73 static int vexpress_sysreg_get_master(void)
74 {
75 	if (readl(vexpress_sysreg_base() + SYS_MISC) & SYS_MISC_MASTERSITE)
76 		return VEXPRESS_SITE_DB2;
77 
78 	return VEXPRESS_SITE_DB1;
79 }
80 
81 void vexpress_flags_set(u32 data)
82 {
83 	writel(~0, vexpress_sysreg_base() + SYS_FLAGSCLR);
84 	writel(data, vexpress_sysreg_base() + SYS_FLAGSSET);
85 }
86 
87 unsigned int vexpress_get_mci_cardin(struct device *dev)
88 {
89 	return readl(vexpress_sysreg_base() + SYS_MCI) & SYS_MCI_CARDIN;
90 }
91 
92 u32 vexpress_get_procid(int site)
93 {
94 	if (site == VEXPRESS_SITE_MASTER)
95 		site = vexpress_sysreg_get_master();
96 
97 	return readl(vexpress_sysreg_base() + (site == VEXPRESS_SITE_DB1 ?
98 			SYS_PROCID0 : SYS_PROCID1));
99 }
100 
101 void __iomem *vexpress_get_24mhz_clock_base(void)
102 {
103 	return vexpress_sysreg_base() + SYS_24MHZ;
104 }
105 
106 
107 void __init vexpress_sysreg_early_init(void __iomem *base)
108 {
109 	__vexpress_sysreg_base = base;
110 
111 	vexpress_config_set_master(vexpress_sysreg_get_master());
112 }
113 
114 
115 /* The sysreg block is just a random collection of various functions... */
116 
117 static struct syscon_platform_data vexpress_sysreg_sys_id_pdata = {
118 	.label = "sys_id",
119 };
120 
121 static struct bgpio_pdata vexpress_sysreg_sys_led_pdata = {
122 	.label = "sys_led",
123 	.base = -1,
124 	.ngpio = 8,
125 };
126 
127 static struct bgpio_pdata vexpress_sysreg_sys_mci_pdata = {
128 	.label = "sys_mci",
129 	.base = -1,
130 	.ngpio = 2,
131 };
132 
133 static struct bgpio_pdata vexpress_sysreg_sys_flash_pdata = {
134 	.label = "sys_flash",
135 	.base = -1,
136 	.ngpio = 1,
137 };
138 
139 static struct syscon_platform_data vexpress_sysreg_sys_misc_pdata = {
140 	.label = "sys_misc",
141 };
142 
143 static struct syscon_platform_data vexpress_sysreg_sys_procid_pdata = {
144 	.label = "sys_procid",
145 };
146 
147 static struct mfd_cell vexpress_sysreg_cells[] = {
148 	{
149 		.name = "syscon",
150 		.num_resources = 1,
151 		.resources = (struct resource []) {
152 			DEFINE_RES_MEM(SYS_ID, 0x4),
153 		},
154 		.platform_data = &vexpress_sysreg_sys_id_pdata,
155 		.pdata_size = sizeof(vexpress_sysreg_sys_id_pdata),
156 	}, {
157 		.name = "basic-mmio-gpio",
158 		.of_compatible = "arm,vexpress-sysreg,sys_led",
159 		.num_resources = 1,
160 		.resources = (struct resource []) {
161 			DEFINE_RES_MEM_NAMED(SYS_LED, 0x4, "dat"),
162 		},
163 		.platform_data = &vexpress_sysreg_sys_led_pdata,
164 		.pdata_size = sizeof(vexpress_sysreg_sys_led_pdata),
165 	}, {
166 		.name = "basic-mmio-gpio",
167 		.of_compatible = "arm,vexpress-sysreg,sys_mci",
168 		.num_resources = 1,
169 		.resources = (struct resource []) {
170 			DEFINE_RES_MEM_NAMED(SYS_MCI, 0x4, "dat"),
171 		},
172 		.platform_data = &vexpress_sysreg_sys_mci_pdata,
173 		.pdata_size = sizeof(vexpress_sysreg_sys_mci_pdata),
174 	}, {
175 		.name = "basic-mmio-gpio",
176 		.of_compatible = "arm,vexpress-sysreg,sys_flash",
177 		.num_resources = 1,
178 		.resources = (struct resource []) {
179 			DEFINE_RES_MEM_NAMED(SYS_FLASH, 0x4, "dat"),
180 		},
181 		.platform_data = &vexpress_sysreg_sys_flash_pdata,
182 		.pdata_size = sizeof(vexpress_sysreg_sys_flash_pdata),
183 	}, {
184 		.name = "syscon",
185 		.num_resources = 1,
186 		.resources = (struct resource []) {
187 			DEFINE_RES_MEM(SYS_MISC, 0x4),
188 		},
189 		.platform_data = &vexpress_sysreg_sys_misc_pdata,
190 		.pdata_size = sizeof(vexpress_sysreg_sys_misc_pdata),
191 	}, {
192 		.name = "syscon",
193 		.num_resources = 1,
194 		.resources = (struct resource []) {
195 			DEFINE_RES_MEM(SYS_PROCID0, 0x8),
196 		},
197 		.platform_data = &vexpress_sysreg_sys_procid_pdata,
198 		.pdata_size = sizeof(vexpress_sysreg_sys_procid_pdata),
199 	}, {
200 		.name = "vexpress-syscfg",
201 		.num_resources = 1,
202 		.resources = (struct resource []) {
203 			DEFINE_RES_MEM(SYS_CFGDATA, 0xc),
204 		},
205 	}
206 };
207 
208 static int vexpress_sysreg_probe(struct platform_device *pdev)
209 {
210 	struct resource *mem;
211 	void __iomem *base;
212 	struct bgpio_chip *mmc_gpio_chip;
213 	u32 dt_hbi;
214 
215 	mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
216 	if (!mem)
217 		return -EINVAL;
218 
219 	base = devm_ioremap(&pdev->dev, mem->start, resource_size(mem));
220 	if (!base)
221 		return -ENOMEM;
222 
223 	vexpress_config_set_master(vexpress_sysreg_get_master());
224 
225 	/* Confirm board type against DT property, if available */
226 	if (of_property_read_u32(of_root, "arm,hbi", &dt_hbi) == 0) {
227 		u32 id = vexpress_get_procid(VEXPRESS_SITE_MASTER);
228 		u32 hbi = (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
229 
230 		if (WARN_ON(dt_hbi != hbi))
231 			dev_warn(&pdev->dev, "DT HBI (%x) is not matching hardware (%x)!\n",
232 					dt_hbi, hbi);
233 	}
234 
235 	/*
236 	 * Duplicated SYS_MCI pseudo-GPIO controller for compatibility with
237 	 * older trees using sysreg node for MMC control lines.
238 	 */
239 	mmc_gpio_chip = devm_kzalloc(&pdev->dev, sizeof(*mmc_gpio_chip),
240 			GFP_KERNEL);
241 	if (!mmc_gpio_chip)
242 		return -ENOMEM;
243 	bgpio_init(mmc_gpio_chip, &pdev->dev, 0x4, base + SYS_MCI,
244 			NULL, NULL, NULL, NULL, 0);
245 	mmc_gpio_chip->gc.ngpio = 2;
246 	gpiochip_add(&mmc_gpio_chip->gc);
247 
248 	return mfd_add_devices(&pdev->dev, PLATFORM_DEVID_AUTO,
249 			vexpress_sysreg_cells,
250 			ARRAY_SIZE(vexpress_sysreg_cells), mem, 0, NULL);
251 }
252 
253 static const struct of_device_id vexpress_sysreg_match[] = {
254 	{ .compatible = "arm,vexpress-sysreg", },
255 	{},
256 };
257 
258 static struct platform_driver vexpress_sysreg_driver = {
259 	.driver = {
260 		.name = "vexpress-sysreg",
261 		.of_match_table = vexpress_sysreg_match,
262 	},
263 	.probe = vexpress_sysreg_probe,
264 };
265 
266 static int __init vexpress_sysreg_init(void)
267 {
268 	struct device_node *node;
269 
270 	/* Need the sysreg early, before any other device... */
271 	for_each_matching_node(node, vexpress_sysreg_match)
272 		of_platform_device_create(node, NULL, NULL);
273 
274 	return platform_driver_register(&vexpress_sysreg_driver);
275 }
276 core_initcall(vexpress_sysreg_init);
277