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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/signal.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];
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
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
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
133static struct 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 int err;
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 err = vexpress_config_get_topo(dev->of_node, &site,
159 &position, &dcc);
160 if (err)
161 return ERR_PTR(err);
162
163 prop = of_find_property(dev->of_node,
164 "arm,vexpress-sysreg,func", NULL);
165 if (!prop)
166 return ERR_PTR(-EINVAL);
167
168 num = prop->length / sizeof(u32) / 2;
169 val = prop->value;
170
171
172
173
174
175 if (num == 1 && of_device_is_compatible(dev->of_node,
176 "arm,vexpress-energy")) {
177 num = 2;
178 energy_quirk[0] = *val;
179 energy_quirk[2] = *val++;
180 energy_quirk[1] = *val;
181 energy_quirk[3] = cpu_to_be32(be32_to_cpup(val) + 1);
182 val = energy_quirk;
183 }
184
185 func = kzalloc(struct_size(func, template, num), GFP_KERNEL);
186 if (!func)
187 return ERR_PTR(-ENOMEM);
188
189 func->syscfg = syscfg;
190 func->num_templates = num;
191
192 for (i = 0; i < num; i++) {
193 u32 function, device;
194
195 function = be32_to_cpup(val++);
196 device = be32_to_cpup(val++);
197
198 dev_dbg(dev, "func %p: %u/%u/%u/%u/%u\n",
199 func, site, position, dcc,
200 function, device);
201
202 func->template[i] = SYS_CFGCTRL_DCC(dcc);
203 func->template[i] |= SYS_CFGCTRL_SITE(site);
204 func->template[i] |= SYS_CFGCTRL_POSITION(position);
205 func->template[i] |= SYS_CFGCTRL_FUNC(function);
206 func->template[i] |= SYS_CFGCTRL_DEVICE(device);
207 }
208
209 vexpress_syscfg_regmap_config.max_register = num - 1;
210
211 func->regmap = regmap_init(dev, NULL, func,
212 &vexpress_syscfg_regmap_config);
213
214 if (IS_ERR(func->regmap)) {
215 void *err = func->regmap;
216
217 kfree(func);
218 return err;
219 }
220
221 list_add(&func->list, &syscfg->funcs);
222
223 return func->regmap;
224}
225
226static void vexpress_syscfg_regmap_exit(struct regmap *regmap, void *context)
227{
228 struct vexpress_syscfg *syscfg = context;
229 struct vexpress_syscfg_func *func, *tmp;
230
231 regmap_exit(regmap);
232
233 list_for_each_entry_safe(func, tmp, &syscfg->funcs, list) {
234 if (func->regmap == regmap) {
235 list_del(&syscfg->funcs);
236 kfree(func);
237 break;
238 }
239 }
240}
241
242static struct vexpress_config_bridge_ops vexpress_syscfg_bridge_ops = {
243 .regmap_init = vexpress_syscfg_regmap_init,
244 .regmap_exit = vexpress_syscfg_regmap_exit,
245};
246
247
248static int vexpress_syscfg_probe(struct platform_device *pdev)
249{
250 struct vexpress_syscfg *syscfg;
251 struct resource *res;
252 struct device *bridge;
253
254 syscfg = devm_kzalloc(&pdev->dev, sizeof(*syscfg), GFP_KERNEL);
255 if (!syscfg)
256 return -ENOMEM;
257 syscfg->dev = &pdev->dev;
258 INIT_LIST_HEAD(&syscfg->funcs);
259
260 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
261 if (!devm_request_mem_region(&pdev->dev, res->start,
262 resource_size(res), pdev->name))
263 return -EBUSY;
264
265 syscfg->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
266 if (!syscfg->base)
267 return -EFAULT;
268
269
270 bridge = vexpress_config_bridge_register(pdev->dev.parent,
271 &vexpress_syscfg_bridge_ops, syscfg);
272
273 return PTR_ERR_OR_ZERO(bridge);
274}
275
276static const struct platform_device_id vexpress_syscfg_id_table[] = {
277 { "vexpress-syscfg", },
278 {},
279};
280
281static struct platform_driver vexpress_syscfg_driver = {
282 .driver.name = "vexpress-syscfg",
283 .id_table = vexpress_syscfg_id_table,
284 .probe = vexpress_syscfg_probe,
285};
286
287static int __init vexpress_syscfg_init(void)
288{
289 return platform_driver_register(&vexpress_syscfg_driver);
290}
291core_initcall(vexpress_syscfg_init);
292
