blob: 3250fc1df0aa35416d5dad4d59e90003ad224169 [file] [log] [blame]
Pawel Moll974cc7b2014-04-23 10:49:31 +01001/*
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) 2014 ARM Limited
12 */
13
14#include <linux/delay.h>
15#include <linux/err.h>
16#include <linux/io.h>
17#include <linux/of.h>
18#include <linux/platform_device.h>
19#include <linux/sched.h>
20#include <linux/slab.h>
21#include <linux/syscore_ops.h>
22#include <linux/vexpress.h>
23
24
25#define SYS_CFGDATA 0x0
26
27#define SYS_CFGCTRL 0x4
28#define SYS_CFGCTRL_START (1 << 31)
29#define SYS_CFGCTRL_WRITE (1 << 30)
30#define SYS_CFGCTRL_DCC(n) (((n) & 0xf) << 26)
31#define SYS_CFGCTRL_FUNC(n) (((n) & 0x3f) << 20)
32#define SYS_CFGCTRL_SITE(n) (((n) & 0x3) << 16)
33#define SYS_CFGCTRL_POSITION(n) (((n) & 0xf) << 12)
34#define SYS_CFGCTRL_DEVICE(n) (((n) & 0xfff) << 0)
35
36#define SYS_CFGSTAT 0x8
37#define SYS_CFGSTAT_ERR (1 << 1)
38#define SYS_CFGSTAT_COMPLETE (1 << 0)
39
40
41struct vexpress_syscfg {
42 struct device *dev;
43 void __iomem *base;
44 struct list_head funcs;
45};
46
47struct vexpress_syscfg_func {
48 struct list_head list;
49 struct vexpress_syscfg *syscfg;
50 struct regmap *regmap;
51 int num_templates;
52 u32 template[0]; /* Keep it last! */
53};
54
55
56static int vexpress_syscfg_exec(struct vexpress_syscfg_func *func,
57 int index, bool write, u32 *data)
58{
59 struct vexpress_syscfg *syscfg = func->syscfg;
60 u32 command, status;
61 int tries;
62 long timeout;
63
64 if (WARN_ON(index > func->num_templates))
65 return -EINVAL;
66
67 command = readl(syscfg->base + SYS_CFGCTRL);
68 if (WARN_ON(command & SYS_CFGCTRL_START))
69 return -EBUSY;
70
71 command = func->template[index];
72 command |= SYS_CFGCTRL_START;
73 command |= write ? SYS_CFGCTRL_WRITE : 0;
74
75 /* Use a canary for reads */
76 if (!write)
77 *data = 0xdeadbeef;
78
79 dev_dbg(syscfg->dev, "func %p, command %x, data %x\n",
80 func, command, *data);
81 writel(*data, syscfg->base + SYS_CFGDATA);
82 writel(0, syscfg->base + SYS_CFGSTAT);
83 writel(command, syscfg->base + SYS_CFGCTRL);
84 mb();
85
86 /* The operation can take ages... Go to sleep, 100us initially */
87 tries = 100;
88 timeout = 100;
89 do {
90 if (!irqs_disabled()) {
91 set_current_state(TASK_INTERRUPTIBLE);
92 schedule_timeout(usecs_to_jiffies(timeout));
93 if (signal_pending(current))
94 return -EINTR;
95 } else {
96 udelay(timeout);
97 }
98
99 status = readl(syscfg->base + SYS_CFGSTAT);
100 if (status & SYS_CFGSTAT_ERR)
101 return -EFAULT;
102
103 if (timeout > 20)
104 timeout -= 20;
105 } while (--tries && !(status & SYS_CFGSTAT_COMPLETE));
106 if (WARN_ON_ONCE(!tries))
107 return -ETIMEDOUT;
108
109 if (!write) {
110 *data = readl(syscfg->base + SYS_CFGDATA);
111 dev_dbg(syscfg->dev, "func %p, read data %x\n", func, *data);
112 }
113
114 return 0;
115}
116
117static int vexpress_syscfg_read(void *context, unsigned int index,
118 unsigned int *val)
119{
120 struct vexpress_syscfg_func *func = context;
121
122 return vexpress_syscfg_exec(func, index, false, val);
123}
124
125static int vexpress_syscfg_write(void *context, unsigned int index,
126 unsigned int val)
127{
128 struct vexpress_syscfg_func *func = context;
129
130 return vexpress_syscfg_exec(func, index, true, &val);
131}
132
133struct regmap_config vexpress_syscfg_regmap_config = {
134 .lock = vexpress_config_lock,
135 .unlock = vexpress_config_unlock,
136 .reg_bits = 32,
137 .val_bits = 32,
138 .reg_read = vexpress_syscfg_read,
139 .reg_write = vexpress_syscfg_write,
140 .reg_format_endian = REGMAP_ENDIAN_LITTLE,
141 .val_format_endian = REGMAP_ENDIAN_LITTLE,
142};
143
144
145static struct regmap *vexpress_syscfg_regmap_init(struct device *dev,
146 void *context)
147{
148 struct platform_device *pdev = to_platform_device(dev);
149 struct vexpress_syscfg *syscfg = context;
150 struct vexpress_syscfg_func *func;
151 struct property *prop;
152 const __be32 *val = NULL;
153 __be32 energy_quirk[4];
154 int num;
155 u32 site, position, dcc;
156 int i;
157
158 if (dev->of_node) {
159 int err = vexpress_config_get_topo(dev->of_node, &site,
160 &position, &dcc);
161
162 if (err)
163 return ERR_PTR(err);
164
165 prop = of_find_property(dev->of_node,
166 "arm,vexpress-sysreg,func", NULL);
167 if (!prop)
168 return ERR_PTR(-EINVAL);
169
170 num = prop->length / sizeof(u32) / 2;
171 val = prop->value;
172 } else {
173 if (pdev->num_resources != 1 ||
174 pdev->resource[0].flags != IORESOURCE_BUS)
175 return ERR_PTR(-EFAULT);
176
177 site = pdev->resource[0].start;
178 if (site == VEXPRESS_SITE_MASTER)
179 site = vexpress_config_get_master();
180 position = 0;
181 dcc = 0;
182 num = 1;
183 }
184
185 /*
186 * "arm,vexpress-energy" function used to be described
187 * by its first device only, now it requires both
188 */
189 if (num == 1 && of_device_is_compatible(dev->of_node,
190 "arm,vexpress-energy")) {
191 num = 2;
192 energy_quirk[0] = *val;
193 energy_quirk[2] = *val++;
194 energy_quirk[1] = *val;
195 energy_quirk[3] = cpu_to_be32(be32_to_cpup(val) + 1);
196 val = energy_quirk;
197 }
198
199 func = kzalloc(sizeof(*func) + sizeof(*func->template) * num,
200 GFP_KERNEL);
201 if (!func)
Dan Carpenterfc96e662014-06-11 13:17:41 +0300202 return ERR_PTR(-ENOMEM);
Pawel Moll974cc7b2014-04-23 10:49:31 +0100203
204 func->syscfg = syscfg;
205 func->num_templates = num;
206
207 for (i = 0; i < num; i++) {
208 u32 function, device;
209
210 if (dev->of_node) {
211 function = be32_to_cpup(val++);
212 device = be32_to_cpup(val++);
213 } else {
214 function = pdev->resource[0].end;
215 device = pdev->id;
216 }
217
218 dev_dbg(dev, "func %p: %u/%u/%u/%u/%u\n",
219 func, site, position, dcc,
220 function, device);
221
222 func->template[i] = SYS_CFGCTRL_DCC(dcc);
223 func->template[i] |= SYS_CFGCTRL_SITE(site);
224 func->template[i] |= SYS_CFGCTRL_POSITION(position);
225 func->template[i] |= SYS_CFGCTRL_FUNC(function);
226 func->template[i] |= SYS_CFGCTRL_DEVICE(device);
227 }
228
229 vexpress_syscfg_regmap_config.max_register = num - 1;
230
231 func->regmap = regmap_init(dev, NULL, func,
232 &vexpress_syscfg_regmap_config);
233
Dan Carpenterfc96e662014-06-11 13:17:41 +0300234 if (IS_ERR(func->regmap)) {
235 void *err = func->regmap;
236
Pawel Moll974cc7b2014-04-23 10:49:31 +0100237 kfree(func);
Dan Carpenterfc96e662014-06-11 13:17:41 +0300238 return err;
239 }
240
241 list_add(&func->list, &syscfg->funcs);
Pawel Moll974cc7b2014-04-23 10:49:31 +0100242
243 return func->regmap;
244}
245
246static void vexpress_syscfg_regmap_exit(struct regmap *regmap, void *context)
247{
248 struct vexpress_syscfg *syscfg = context;
249 struct vexpress_syscfg_func *func, *tmp;
250
251 regmap_exit(regmap);
252
253 list_for_each_entry_safe(func, tmp, &syscfg->funcs, list) {
254 if (func->regmap == regmap) {
255 list_del(&syscfg->funcs);
256 kfree(func);
257 break;
258 }
259 }
260}
261
262static struct vexpress_config_bridge_ops vexpress_syscfg_bridge_ops = {
263 .regmap_init = vexpress_syscfg_regmap_init,
264 .regmap_exit = vexpress_syscfg_regmap_exit,
265};
266
267
268/* Non-DT hack, to be gone... */
269static struct device *vexpress_syscfg_bridge;
270
271int vexpress_syscfg_device_register(struct platform_device *pdev)
272{
273 pdev->dev.parent = vexpress_syscfg_bridge;
274
275 return platform_device_register(pdev);
276}
277
278
279int vexpress_syscfg_probe(struct platform_device *pdev)
280{
281 struct vexpress_syscfg *syscfg;
282 struct resource *res;
283 struct device *bridge;
284
285 syscfg = devm_kzalloc(&pdev->dev, sizeof(*syscfg), GFP_KERNEL);
286 if (!syscfg)
287 return -ENOMEM;
288 syscfg->dev = &pdev->dev;
289 INIT_LIST_HEAD(&syscfg->funcs);
290
291 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
292 if (!devm_request_mem_region(&pdev->dev, res->start,
293 resource_size(res), pdev->name))
294 return -EBUSY;
295
296 syscfg->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
297 if (!syscfg->base)
298 return -EFAULT;
299
300 /* Must use dev.parent (MFD), as that's where DT phandle points at... */
301 bridge = vexpress_config_bridge_register(pdev->dev.parent,
302 &vexpress_syscfg_bridge_ops, syscfg);
303 if (IS_ERR(bridge))
304 return PTR_ERR(bridge);
305
306 /* Non-DT case */
307 if (!pdev->dev.of_node)
308 vexpress_syscfg_bridge = bridge;
309
310 return 0;
311}
312
313static const struct platform_device_id vexpress_syscfg_id_table[] = {
314 { "vexpress-syscfg", },
315 {},
316};
317
318static struct platform_driver vexpress_syscfg_driver = {
319 .driver.name = "vexpress-syscfg",
320 .id_table = vexpress_syscfg_id_table,
321 .probe = vexpress_syscfg_probe,
322};
323
324static int __init vexpress_syscfg_init(void)
325{
326 return platform_driver_register(&vexpress_syscfg_driver);
327}
328core_initcall(vexpress_syscfg_init);