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_platform.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[] __counted_by(num_templates); /* 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(lock: &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(np: node, propname: name, out_value: 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, name: "arm,vexpress,site" , val: 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, name: "arm,vexpress,position" , val: position); |
116 | vexpress_config_find_prop(node, name: "arm,vexpress,dcc" , val: 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: 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: dev->parent); |
137 | if (WARN_ON(!bridge)) |
138 | return ERR_PTR(error: -EINVAL); |
139 | |
140 | res = devres_alloc(vexpress_config_devres_release, sizeof(*res), |
141 | GFP_KERNEL); |
142 | if (!res) |
143 | return ERR_PTR(error: -ENOMEM); |
144 | |
145 | regmap = (bridge->ops->regmap_init)(dev, bridge->context); |
146 | if (IS_ERR(ptr: 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(addr: 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(val: *data, addr: syscfg->base + SYS_CFGDATA); |
184 | writel(val: 0, addr: syscfg->base + SYS_CFGSTAT); |
185 | writel(val: command, addr: 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(timeout: usecs_to_jiffies(u: timeout)); |
195 | if (signal_pending(current)) |
196 | return -EINTR; |
197 | } else { |
198 | udelay(timeout); |
199 | } |
200 | |
201 | status = readl(addr: 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(addr: 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, write: false, data: 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, write: true, data: &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(node: dev->of_node, site: &site, |
261 | position: &position, dcc: &dcc); |
262 | if (err) |
263 | return ERR_PTR(error: err); |
264 | |
265 | prop = of_find_property(np: dev->of_node, |
266 | name: "arm,vexpress-sysreg,func" , NULL); |
267 | if (!prop) |
268 | return ERR_PTR(error: -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(device: 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(error: -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(p: val++); |
298 | device = be32_to_cpup(p: 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(ptr: func->regmap)) { |
317 | void *err = func->regmap; |
318 | |
319 | kfree(objp: func); |
320 | return err; |
321 | } |
322 | |
323 | list_add(new: &func->list, head: &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(map: regmap); |
334 | |
335 | list_for_each_entry_safe(func, tmp, &syscfg->funcs, list) { |
336 | if (func->regmap == regmap) { |
337 | list_del(entry: &syscfg->funcs); |
338 | kfree(objp: 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 vexpress_config_bridge *bridge; |
354 | struct device_node *node; |
355 | int master; |
356 | u32 dt_hbi; |
357 | |
358 | syscfg = devm_kzalloc(dev: &pdev->dev, size: sizeof(*syscfg), GFP_KERNEL); |
359 | if (!syscfg) |
360 | return -ENOMEM; |
361 | syscfg->dev = &pdev->dev; |
362 | INIT_LIST_HEAD(list: &syscfg->funcs); |
363 | |
364 | syscfg->base = devm_platform_ioremap_resource(pdev, index: 0); |
365 | if (IS_ERR(ptr: syscfg->base)) |
366 | return PTR_ERR(ptr: syscfg->base); |
367 | |
368 | bridge = devm_kmalloc(dev: &pdev->dev, size: sizeof(*bridge), GFP_KERNEL); |
369 | if (!bridge) |
370 | return -ENOMEM; |
371 | |
372 | bridge->ops = &vexpress_syscfg_bridge_ops; |
373 | bridge->context = syscfg; |
374 | |
375 | dev_set_drvdata(dev: &pdev->dev, data: bridge); |
376 | |
377 | master = readl(addr: syscfg->base + SYS_MISC) & SYS_MISC_MASTERSITE ? |
378 | VEXPRESS_SITE_DB2 : VEXPRESS_SITE_DB1; |
379 | vexpress_config_set_master(site: master); |
380 | |
381 | /* Confirm board type against DT property, if available */ |
382 | if (of_property_read_u32(np: of_root, propname: "arm,hbi" , out_value: &dt_hbi) == 0) { |
383 | u32 id = readl(addr: syscfg->base + (master == VEXPRESS_SITE_DB1 ? |
384 | SYS_PROCID0 : SYS_PROCID1)); |
385 | u32 hbi = (id >> SYS_PROCIDx_HBI_SHIFT) & SYS_HBI_MASK; |
386 | |
387 | if (WARN_ON(dt_hbi != hbi)) |
388 | dev_warn(&pdev->dev, "DT HBI (%x) is not matching hardware (%x)!\n" , |
389 | dt_hbi, hbi); |
390 | } |
391 | |
392 | for_each_compatible_node(node, NULL, "arm,vexpress,config-bus" ) { |
393 | struct device_node *bridge_np; |
394 | |
395 | bridge_np = of_parse_phandle(np: node, phandle_name: "arm,vexpress,config-bridge" , index: 0); |
396 | if (bridge_np != pdev->dev.parent->of_node) |
397 | continue; |
398 | |
399 | of_platform_populate(root: node, NULL, NULL, parent: &pdev->dev); |
400 | } |
401 | |
402 | return 0; |
403 | } |
404 | |
405 | static const struct platform_device_id vexpress_syscfg_id_table[] = { |
406 | { "vexpress-syscfg" , }, |
407 | {}, |
408 | }; |
409 | MODULE_DEVICE_TABLE(platform, vexpress_syscfg_id_table); |
410 | |
411 | static struct platform_driver vexpress_syscfg_driver = { |
412 | .driver.name = "vexpress-syscfg" , |
413 | .id_table = vexpress_syscfg_id_table, |
414 | .probe = vexpress_syscfg_probe, |
415 | }; |
416 | module_platform_driver(vexpress_syscfg_driver); |
417 | MODULE_LICENSE("GPL v2" ); |
418 | |