forked from torvalds/linux
-
Notifications
You must be signed in to change notification settings - Fork 0
/
vexpress-config.c
419 lines (334 loc) · 9.96 KB
/
vexpress-config.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
// SPDX-License-Identifier: GPL-2.0-only
/*
*
* Copyright (C) 2014 ARM Limited
*/
#include <linux/err.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/of_device.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
#include <linux/vexpress.h>
#define SYS_MISC 0x0
#define SYS_MISC_MASTERSITE (1 << 14)
#define SYS_PROCID0 0x24
#define SYS_PROCID1 0x28
#define SYS_HBI_MASK 0xfff
#define SYS_PROCIDx_HBI_SHIFT 0
#define SYS_CFGDATA 0x40
#define SYS_CFGCTRL 0x44
#define SYS_CFGCTRL_START (1 << 31)
#define SYS_CFGCTRL_WRITE (1 << 30)
#define SYS_CFGCTRL_DCC(n) (((n) & 0xf) << 26)
#define SYS_CFGCTRL_FUNC(n) (((n) & 0x3f) << 20)
#define SYS_CFGCTRL_SITE(n) (((n) & 0x3) << 16)
#define SYS_CFGCTRL_POSITION(n) (((n) & 0xf) << 12)
#define SYS_CFGCTRL_DEVICE(n) (((n) & 0xfff) << 0)
#define SYS_CFGSTAT 0x48
#define SYS_CFGSTAT_ERR (1 << 1)
#define SYS_CFGSTAT_COMPLETE (1 << 0)
#define VEXPRESS_SITE_MB 0
#define VEXPRESS_SITE_DB1 1
#define VEXPRESS_SITE_DB2 2
#define VEXPRESS_SITE_MASTER 0xf
struct vexpress_syscfg {
struct device *dev;
void __iomem *base;
struct list_head funcs;
};
struct vexpress_syscfg_func {
struct list_head list;
struct vexpress_syscfg *syscfg;
struct regmap *regmap;
int num_templates;
u32 template[]; /* Keep it last! */
};
struct vexpress_config_bridge_ops {
struct regmap * (*regmap_init)(struct device *dev, void *context);
void (*regmap_exit)(struct regmap *regmap, void *context);
};
struct vexpress_config_bridge {
struct vexpress_config_bridge_ops *ops;
void *context;
};
static DEFINE_MUTEX(vexpress_config_mutex);
static u32 vexpress_config_site_master = VEXPRESS_SITE_MASTER;
static void vexpress_config_set_master(u32 site)
{
vexpress_config_site_master = site;
}
static void vexpress_config_lock(void *arg)
{
mutex_lock(&vexpress_config_mutex);
}
static void vexpress_config_unlock(void *arg)
{
mutex_unlock(&vexpress_config_mutex);
}
static void vexpress_config_find_prop(struct device_node *node,
const char *name, u32 *val)
{
/* Default value */
*val = 0;
of_node_get(node);
while (node) {
if (of_property_read_u32(node, name, val) == 0) {
of_node_put(node);
return;
}
node = of_get_next_parent(node);
}
}
static int vexpress_config_get_topo(struct device_node *node, u32 *site,
u32 *position, u32 *dcc)
{
vexpress_config_find_prop(node, "arm,vexpress,site", site);
if (*site == VEXPRESS_SITE_MASTER)
*site = vexpress_config_site_master;
if (WARN_ON(vexpress_config_site_master == VEXPRESS_SITE_MASTER))
return -EINVAL;
vexpress_config_find_prop(node, "arm,vexpress,position", position);
vexpress_config_find_prop(node, "arm,vexpress,dcc", dcc);
return 0;
}
static void vexpress_config_devres_release(struct device *dev, void *res)
{
struct vexpress_config_bridge *bridge = dev_get_drvdata(dev->parent);
struct regmap *regmap = res;
bridge->ops->regmap_exit(regmap, bridge->context);
}
struct regmap *devm_regmap_init_vexpress_config(struct device *dev)
{
struct vexpress_config_bridge *bridge;
struct regmap *regmap;
struct regmap **res;
bridge = dev_get_drvdata(dev->parent);
if (WARN_ON(!bridge))
return ERR_PTR(-EINVAL);
res = devres_alloc(vexpress_config_devres_release, sizeof(*res),
GFP_KERNEL);
if (!res)
return ERR_PTR(-ENOMEM);
regmap = (bridge->ops->regmap_init)(dev, bridge->context);
if (IS_ERR(regmap)) {
devres_free(res);
return regmap;
}
*res = regmap;
devres_add(dev, res);
return regmap;
}
EXPORT_SYMBOL_GPL(devm_regmap_init_vexpress_config);
static int vexpress_syscfg_exec(struct vexpress_syscfg_func *func,
int index, bool write, u32 *data)
{
struct vexpress_syscfg *syscfg = func->syscfg;
u32 command, status;
int tries;
long timeout;
if (WARN_ON(index >= func->num_templates))
return -EINVAL;
command = readl(syscfg->base + SYS_CFGCTRL);
if (WARN_ON(command & SYS_CFGCTRL_START))
return -EBUSY;
command = func->template[index];
command |= SYS_CFGCTRL_START;
command |= write ? SYS_CFGCTRL_WRITE : 0;
/* Use a canary for reads */
if (!write)
*data = 0xdeadbeef;
dev_dbg(syscfg->dev, "func %p, command %x, data %x\n",
func, command, *data);
writel(*data, syscfg->base + SYS_CFGDATA);
writel(0, syscfg->base + SYS_CFGSTAT);
writel(command, syscfg->base + SYS_CFGCTRL);
mb();
/* The operation can take ages... Go to sleep, 100us initially */
tries = 100;
timeout = 100;
do {
if (!irqs_disabled()) {
set_current_state(TASK_INTERRUPTIBLE);
schedule_timeout(usecs_to_jiffies(timeout));
if (signal_pending(current))
return -EINTR;
} else {
udelay(timeout);
}
status = readl(syscfg->base + SYS_CFGSTAT);
if (status & SYS_CFGSTAT_ERR)
return -EFAULT;
if (timeout > 20)
timeout -= 20;
} while (--tries && !(status & SYS_CFGSTAT_COMPLETE));
if (WARN_ON_ONCE(!tries))
return -ETIMEDOUT;
if (!write) {
*data = readl(syscfg->base + SYS_CFGDATA);
dev_dbg(syscfg->dev, "func %p, read data %x\n", func, *data);
}
return 0;
}
static int vexpress_syscfg_read(void *context, unsigned int index,
unsigned int *val)
{
struct vexpress_syscfg_func *func = context;
return vexpress_syscfg_exec(func, index, false, val);
}
static int vexpress_syscfg_write(void *context, unsigned int index,
unsigned int val)
{
struct vexpress_syscfg_func *func = context;
return vexpress_syscfg_exec(func, index, true, &val);
}
static struct regmap_config vexpress_syscfg_regmap_config = {
.lock = vexpress_config_lock,
.unlock = vexpress_config_unlock,
.reg_bits = 32,
.val_bits = 32,
.reg_read = vexpress_syscfg_read,
.reg_write = vexpress_syscfg_write,
.reg_format_endian = REGMAP_ENDIAN_LITTLE,
.val_format_endian = REGMAP_ENDIAN_LITTLE,
};
static struct regmap *vexpress_syscfg_regmap_init(struct device *dev,
void *context)
{
int err;
struct vexpress_syscfg *syscfg = context;
struct vexpress_syscfg_func *func;
struct property *prop;
const __be32 *val = NULL;
__be32 energy_quirk[4];
int num;
u32 site, position, dcc;
int i;
err = vexpress_config_get_topo(dev->of_node, &site,
&position, &dcc);
if (err)
return ERR_PTR(err);
prop = of_find_property(dev->of_node,
"arm,vexpress-sysreg,func", NULL);
if (!prop)
return ERR_PTR(-EINVAL);
num = prop->length / sizeof(u32) / 2;
val = prop->value;
/*
* "arm,vexpress-energy" function used to be described
* by its first device only, now it requires both
*/
if (num == 1 && of_device_is_compatible(dev->of_node,
"arm,vexpress-energy")) {
num = 2;
energy_quirk[0] = *val;
energy_quirk[2] = *val++;
energy_quirk[1] = *val;
energy_quirk[3] = cpu_to_be32(be32_to_cpup(val) + 1);
val = energy_quirk;
}
func = kzalloc(struct_size(func, template, num), GFP_KERNEL);
if (!func)
return ERR_PTR(-ENOMEM);
func->syscfg = syscfg;
func->num_templates = num;
for (i = 0; i < num; i++) {
u32 function, device;
function = be32_to_cpup(val++);
device = be32_to_cpup(val++);
dev_dbg(dev, "func %p: %u/%u/%u/%u/%u\n",
func, site, position, dcc,
function, device);
func->template[i] = SYS_CFGCTRL_DCC(dcc);
func->template[i] |= SYS_CFGCTRL_SITE(site);
func->template[i] |= SYS_CFGCTRL_POSITION(position);
func->template[i] |= SYS_CFGCTRL_FUNC(function);
func->template[i] |= SYS_CFGCTRL_DEVICE(device);
}
vexpress_syscfg_regmap_config.max_register = num - 1;
func->regmap = regmap_init(dev, NULL, func,
&vexpress_syscfg_regmap_config);
if (IS_ERR(func->regmap)) {
void *err = func->regmap;
kfree(func);
return err;
}
list_add(&func->list, &syscfg->funcs);
return func->regmap;
}
static void vexpress_syscfg_regmap_exit(struct regmap *regmap, void *context)
{
struct vexpress_syscfg *syscfg = context;
struct vexpress_syscfg_func *func, *tmp;
regmap_exit(regmap);
list_for_each_entry_safe(func, tmp, &syscfg->funcs, list) {
if (func->regmap == regmap) {
list_del(&syscfg->funcs);
kfree(func);
break;
}
}
}
static struct vexpress_config_bridge_ops vexpress_syscfg_bridge_ops = {
.regmap_init = vexpress_syscfg_regmap_init,
.regmap_exit = vexpress_syscfg_regmap_exit,
};
static int vexpress_syscfg_probe(struct platform_device *pdev)
{
struct vexpress_syscfg *syscfg;
struct resource *res;
struct vexpress_config_bridge *bridge;
struct device_node *node;
int master;
u32 dt_hbi;
syscfg = devm_kzalloc(&pdev->dev, sizeof(*syscfg), GFP_KERNEL);
if (!syscfg)
return -ENOMEM;
syscfg->dev = &pdev->dev;
INIT_LIST_HEAD(&syscfg->funcs);
res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
syscfg->base = devm_ioremap_resource(&pdev->dev, res);
if (IS_ERR(syscfg->base))
return PTR_ERR(syscfg->base);
bridge = devm_kmalloc(&pdev->dev, sizeof(*bridge), GFP_KERNEL);
if (!bridge)
return -ENOMEM;
bridge->ops = &vexpress_syscfg_bridge_ops;
bridge->context = syscfg;
dev_set_drvdata(&pdev->dev, bridge);
master = readl(syscfg->base + SYS_MISC) & SYS_MISC_MASTERSITE ?
VEXPRESS_SITE_DB2 : VEXPRESS_SITE_DB1;
vexpress_config_set_master(master);
/* Confirm board type against DT property, if available */
if (of_property_read_u32(of_root, "arm,hbi", &dt_hbi) == 0) {
u32 id = readl(syscfg->base + (master == VEXPRESS_SITE_DB1 ?
SYS_PROCID0 : SYS_PROCID1));
u32 hbi = (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
if (WARN_ON(dt_hbi != hbi))
dev_warn(&pdev->dev, "DT HBI (%x) is not matching hardware (%x)!\n",
dt_hbi, hbi);
}
for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") {
struct device_node *bridge_np;
bridge_np = of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
if (bridge_np != pdev->dev.parent->of_node)
continue;
of_platform_populate(node, NULL, NULL, &pdev->dev);
}
return 0;
}
static const struct platform_device_id vexpress_syscfg_id_table[] = {
{ "vexpress-syscfg", },
{},
};
MODULE_DEVICE_TABLE(platform, vexpress_syscfg_id_table);
static struct platform_driver vexpress_syscfg_driver = {
.driver.name = "vexpress-syscfg",
.id_table = vexpress_syscfg_id_table,
.probe = vexpress_syscfg_probe,
};
module_platform_driver(vexpress_syscfg_driver);
MODULE_LICENSE("GPL v2");