Merge tag 'v5.10-rc1' into kvmarm-master/next
[linux-2.6-microblaze.git] / drivers / bus / vexpress-config.c
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  *
4  * Copyright (C) 2014 ARM Limited
5  */
6
7 #include <linux/err.h>
8 #include <linux/init.h>
9 #include <linux/io.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/platform_device.h>
13 #include <linux/of_device.h>
14 #include <linux/sched/signal.h>
15 #include <linux/slab.h>
16 #include <linux/vexpress.h>
17
18 #define SYS_MISC                0x0
19 #define SYS_MISC_MASTERSITE     (1 << 14)
20
21 #define SYS_PROCID0             0x24
22 #define SYS_PROCID1             0x28
23 #define SYS_HBI_MASK            0xfff
24 #define SYS_PROCIDx_HBI_SHIFT   0
25
26 #define SYS_CFGDATA             0x40
27
28 #define SYS_CFGCTRL             0x44
29 #define SYS_CFGCTRL_START       (1 << 31)
30 #define SYS_CFGCTRL_WRITE       (1 << 30)
31 #define SYS_CFGCTRL_DCC(n)      (((n) & 0xf) << 26)
32 #define SYS_CFGCTRL_FUNC(n)     (((n) & 0x3f) << 20)
33 #define SYS_CFGCTRL_SITE(n)     (((n) & 0x3) << 16)
34 #define SYS_CFGCTRL_POSITION(n) (((n) & 0xf) << 12)
35 #define SYS_CFGCTRL_DEVICE(n)   (((n) & 0xfff) << 0)
36
37 #define SYS_CFGSTAT             0x48
38 #define SYS_CFGSTAT_ERR         (1 << 1)
39 #define SYS_CFGSTAT_COMPLETE    (1 << 0)
40
41 #define VEXPRESS_SITE_MB                0
42 #define VEXPRESS_SITE_DB1               1
43 #define VEXPRESS_SITE_DB2               2
44 #define VEXPRESS_SITE_MASTER            0xf
45
46 struct vexpress_syscfg {
47         struct device *dev;
48         void __iomem *base;
49         struct list_head funcs;
50 };
51
52 struct vexpress_syscfg_func {
53         struct list_head list;
54         struct vexpress_syscfg *syscfg;
55         struct regmap *regmap;
56         int num_templates;
57         u32 template[]; /* Keep it last! */
58 };
59
60 struct vexpress_config_bridge_ops {
61         struct regmap * (*regmap_init)(struct device *dev, void *context);
62         void (*regmap_exit)(struct regmap *regmap, void *context);
63 };
64
65 struct vexpress_config_bridge {
66         struct vexpress_config_bridge_ops *ops;
67         void *context;
68 };
69
70
71 static DEFINE_MUTEX(vexpress_config_mutex);
72 static u32 vexpress_config_site_master = VEXPRESS_SITE_MASTER;
73
74
75 static void vexpress_config_set_master(u32 site)
76 {
77         vexpress_config_site_master = site;
78 }
79
80 static void vexpress_config_lock(void *arg)
81 {
82         mutex_lock(&vexpress_config_mutex);
83 }
84
85 static void vexpress_config_unlock(void *arg)
86 {
87         mutex_unlock(&vexpress_config_mutex);
88 }
89
90
91 static void vexpress_config_find_prop(struct device_node *node,
92                 const char *name, u32 *val)
93 {
94         /* Default value */
95         *val = 0;
96
97         of_node_get(node);
98         while (node) {
99                 if (of_property_read_u32(node, name, val) == 0) {
100                         of_node_put(node);
101                         return;
102                 }
103                 node = of_get_next_parent(node);
104         }
105 }
106
107 static int vexpress_config_get_topo(struct device_node *node, u32 *site,
108                 u32 *position, u32 *dcc)
109 {
110         vexpress_config_find_prop(node, "arm,vexpress,site", site);
111         if (*site == VEXPRESS_SITE_MASTER)
112                 *site = vexpress_config_site_master;
113         if (WARN_ON(vexpress_config_site_master == VEXPRESS_SITE_MASTER))
114                 return -EINVAL;
115         vexpress_config_find_prop(node, "arm,vexpress,position", position);
116         vexpress_config_find_prop(node, "arm,vexpress,dcc", dcc);
117
118         return 0;
119 }
120
121
122 static void vexpress_config_devres_release(struct device *dev, void *res)
123 {
124         struct vexpress_config_bridge *bridge = dev_get_drvdata(dev->parent);
125         struct regmap *regmap = res;
126
127         bridge->ops->regmap_exit(regmap, bridge->context);
128 }
129
130 struct regmap *devm_regmap_init_vexpress_config(struct device *dev)
131 {
132         struct vexpress_config_bridge *bridge;
133         struct regmap *regmap;
134         struct regmap **res;
135
136         bridge = dev_get_drvdata(dev->parent);
137         if (WARN_ON(!bridge))
138                 return ERR_PTR(-EINVAL);
139
140         res = devres_alloc(vexpress_config_devres_release, sizeof(*res),
141                         GFP_KERNEL);
142         if (!res)
143                 return ERR_PTR(-ENOMEM);
144
145         regmap = (bridge->ops->regmap_init)(dev, bridge->context);
146         if (IS_ERR(regmap)) {
147                 devres_free(res);
148                 return regmap;
149         }
150
151         *res = regmap;
152         devres_add(dev, res);
153
154         return regmap;
155 }
156 EXPORT_SYMBOL_GPL(devm_regmap_init_vexpress_config);
157
158 static int vexpress_syscfg_exec(struct vexpress_syscfg_func *func,
159                 int index, bool write, u32 *data)
160 {
161         struct vexpress_syscfg *syscfg = func->syscfg;
162         u32 command, status;
163         int tries;
164         long timeout;
165
166         if (WARN_ON(index >= func->num_templates))
167                 return -EINVAL;
168
169         command = readl(syscfg->base + SYS_CFGCTRL);
170         if (WARN_ON(command & SYS_CFGCTRL_START))
171                 return -EBUSY;
172
173         command = func->template[index];
174         command |= SYS_CFGCTRL_START;
175         command |= write ? SYS_CFGCTRL_WRITE : 0;
176
177         /* Use a canary for reads */
178         if (!write)
179                 *data = 0xdeadbeef;
180
181         dev_dbg(syscfg->dev, "func %p, command %x, data %x\n",
182                         func, command, *data);
183         writel(*data, syscfg->base + SYS_CFGDATA);
184         writel(0, syscfg->base + SYS_CFGSTAT);
185         writel(command, syscfg->base + SYS_CFGCTRL);
186         mb();
187
188         /* The operation can take ages... Go to sleep, 100us initially */
189         tries = 100;
190         timeout = 100;
191         do {
192                 if (!irqs_disabled()) {
193                         set_current_state(TASK_INTERRUPTIBLE);
194                         schedule_timeout(usecs_to_jiffies(timeout));
195                         if (signal_pending(current))
196                                 return -EINTR;
197                 } else {
198                         udelay(timeout);
199                 }
200
201                 status = readl(syscfg->base + SYS_CFGSTAT);
202                 if (status & SYS_CFGSTAT_ERR)
203                         return -EFAULT;
204
205                 if (timeout > 20)
206                         timeout -= 20;
207         } while (--tries && !(status & SYS_CFGSTAT_COMPLETE));
208         if (WARN_ON_ONCE(!tries))
209                 return -ETIMEDOUT;
210
211         if (!write) {
212                 *data = readl(syscfg->base + SYS_CFGDATA);
213                 dev_dbg(syscfg->dev, "func %p, read data %x\n", func, *data);
214         }
215
216         return 0;
217 }
218
219 static int vexpress_syscfg_read(void *context, unsigned int index,
220                 unsigned int *val)
221 {
222         struct vexpress_syscfg_func *func = context;
223
224         return vexpress_syscfg_exec(func, index, false, val);
225 }
226
227 static int vexpress_syscfg_write(void *context, unsigned int index,
228                 unsigned int val)
229 {
230         struct vexpress_syscfg_func *func = context;
231
232         return vexpress_syscfg_exec(func, index, true, &val);
233 }
234
235 static struct regmap_config vexpress_syscfg_regmap_config = {
236         .lock = vexpress_config_lock,
237         .unlock = vexpress_config_unlock,
238         .reg_bits = 32,
239         .val_bits = 32,
240         .reg_read = vexpress_syscfg_read,
241         .reg_write = vexpress_syscfg_write,
242         .reg_format_endian = REGMAP_ENDIAN_LITTLE,
243         .val_format_endian = REGMAP_ENDIAN_LITTLE,
244 };
245
246
247 static struct regmap *vexpress_syscfg_regmap_init(struct device *dev,
248                 void *context)
249 {
250         int err;
251         struct vexpress_syscfg *syscfg = context;
252         struct vexpress_syscfg_func *func;
253         struct property *prop;
254         const __be32 *val = NULL;
255         __be32 energy_quirk[4];
256         int num;
257         u32 site, position, dcc;
258         int i;
259
260         err = vexpress_config_get_topo(dev->of_node, &site,
261                                 &position, &dcc);
262         if (err)
263                 return ERR_PTR(err);
264
265         prop = of_find_property(dev->of_node,
266                         "arm,vexpress-sysreg,func", NULL);
267         if (!prop)
268                 return ERR_PTR(-EINVAL);
269
270         num = prop->length / sizeof(u32) / 2;
271         val = prop->value;
272
273         /*
274          * "arm,vexpress-energy" function used to be described
275          * by its first device only, now it requires both
276          */
277         if (num == 1 && of_device_is_compatible(dev->of_node,
278                         "arm,vexpress-energy")) {
279                 num = 2;
280                 energy_quirk[0] = *val;
281                 energy_quirk[2] = *val++;
282                 energy_quirk[1] = *val;
283                 energy_quirk[3] = cpu_to_be32(be32_to_cpup(val) + 1);
284                 val = energy_quirk;
285         }
286
287         func = kzalloc(struct_size(func, template, num), GFP_KERNEL);
288         if (!func)
289                 return ERR_PTR(-ENOMEM);
290
291         func->syscfg = syscfg;
292         func->num_templates = num;
293
294         for (i = 0; i < num; i++) {
295                 u32 function, device;
296
297                 function = be32_to_cpup(val++);
298                 device = be32_to_cpup(val++);
299
300                 dev_dbg(dev, "func %p: %u/%u/%u/%u/%u\n",
301                                 func, site, position, dcc,
302                                 function, device);
303
304                 func->template[i] = SYS_CFGCTRL_DCC(dcc);
305                 func->template[i] |= SYS_CFGCTRL_SITE(site);
306                 func->template[i] |= SYS_CFGCTRL_POSITION(position);
307                 func->template[i] |= SYS_CFGCTRL_FUNC(function);
308                 func->template[i] |= SYS_CFGCTRL_DEVICE(device);
309         }
310
311         vexpress_syscfg_regmap_config.max_register = num - 1;
312
313         func->regmap = regmap_init(dev, NULL, func,
314                         &vexpress_syscfg_regmap_config);
315
316         if (IS_ERR(func->regmap)) {
317                 void *err = func->regmap;
318
319                 kfree(func);
320                 return err;
321         }
322
323         list_add(&func->list, &syscfg->funcs);
324
325         return func->regmap;
326 }
327
328 static void vexpress_syscfg_regmap_exit(struct regmap *regmap, void *context)
329 {
330         struct vexpress_syscfg *syscfg = context;
331         struct vexpress_syscfg_func *func, *tmp;
332
333         regmap_exit(regmap);
334
335         list_for_each_entry_safe(func, tmp, &syscfg->funcs, list) {
336                 if (func->regmap == regmap) {
337                         list_del(&syscfg->funcs);
338                         kfree(func);
339                         break;
340                 }
341         }
342 }
343
344 static struct vexpress_config_bridge_ops vexpress_syscfg_bridge_ops = {
345         .regmap_init = vexpress_syscfg_regmap_init,
346         .regmap_exit = vexpress_syscfg_regmap_exit,
347 };
348
349
350 static int vexpress_syscfg_probe(struct platform_device *pdev)
351 {
352         struct vexpress_syscfg *syscfg;
353         struct resource *res;
354         struct vexpress_config_bridge *bridge;
355         struct device_node *node;
356         int master;
357         u32 dt_hbi;
358
359         syscfg = devm_kzalloc(&pdev->dev, sizeof(*syscfg), GFP_KERNEL);
360         if (!syscfg)
361                 return -ENOMEM;
362         syscfg->dev = &pdev->dev;
363         INIT_LIST_HEAD(&syscfg->funcs);
364
365         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
366         syscfg->base = devm_ioremap_resource(&pdev->dev, res);
367         if (IS_ERR(syscfg->base))
368                 return PTR_ERR(syscfg->base);
369
370         bridge = devm_kmalloc(&pdev->dev, sizeof(*bridge), GFP_KERNEL);
371         if (!bridge)
372                 return -ENOMEM;
373
374         bridge->ops = &vexpress_syscfg_bridge_ops;
375         bridge->context = syscfg;
376
377         dev_set_drvdata(&pdev->dev, bridge);
378
379         master = readl(syscfg->base + SYS_MISC) & SYS_MISC_MASTERSITE ?
380                         VEXPRESS_SITE_DB2 : VEXPRESS_SITE_DB1;
381         vexpress_config_set_master(master);
382
383         /* Confirm board type against DT property, if available */
384         if (of_property_read_u32(of_root, "arm,hbi", &dt_hbi) == 0) {
385                 u32 id = readl(syscfg->base + (master == VEXPRESS_SITE_DB1 ?
386                                  SYS_PROCID0 : SYS_PROCID1));
387                 u32 hbi = (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK;
388
389                 if (WARN_ON(dt_hbi != hbi))
390                         dev_warn(&pdev->dev, "DT HBI (%x) is not matching hardware (%x)!\n",
391                                         dt_hbi, hbi);
392         }
393
394         for_each_compatible_node(node, NULL, "arm,vexpress,config-bus") {
395                 struct device_node *bridge_np;
396
397                 bridge_np = of_parse_phandle(node, "arm,vexpress,config-bridge", 0);
398                 if (bridge_np != pdev->dev.parent->of_node)
399                         continue;
400
401                 of_platform_populate(node, NULL, NULL, &pdev->dev);
402         }
403
404         return 0;
405 }
406
407 static const struct platform_device_id vexpress_syscfg_id_table[] = {
408         { "vexpress-syscfg", },
409         {},
410 };
411 MODULE_DEVICE_TABLE(platform, vexpress_syscfg_id_table);
412
413 static struct platform_driver vexpress_syscfg_driver = {
414         .driver.name = "vexpress-syscfg",
415         .id_table = vexpress_syscfg_id_table,
416         .probe = vexpress_syscfg_probe,
417 };
418 module_platform_driver(vexpress_syscfg_driver);
419 MODULE_LICENSE("GPL v2");