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502b431c | 1 | // SPDX-License-Identifier: GPL-2.0 |
4e3d6065 | 2 | /* |
60aa8782 | 3 | * Defines interfaces for interacting with the Raspberry Pi firmware's |
4e3d6065 EA |
4 | * property channel. |
5 | * | |
6 | * Copyright © 2015 Broadcom | |
4e3d6065 EA |
7 | */ |
8 | ||
9 | #include <linux/dma-mapping.h> | |
1e7c5735 | 10 | #include <linux/kref.h> |
4e3d6065 EA |
11 | #include <linux/mailbox_client.h> |
12 | #include <linux/module.h> | |
5b45759c | 13 | #include <linux/of.h> |
4e3d6065 EA |
14 | #include <linux/of_platform.h> |
15 | #include <linux/platform_device.h> | |
91c6ada6 | 16 | #include <linux/slab.h> |
4e3d6065 EA |
17 | #include <soc/bcm2835/raspberrypi-firmware.h> |
18 | ||
19 | #define MBOX_MSG(chan, data28) (((data28) & ~0xf) | ((chan) & 0xf)) | |
20 | #define MBOX_CHAN(msg) ((msg) & 0xf) | |
21 | #define MBOX_DATA28(msg) ((msg) & ~0xf) | |
22 | #define MBOX_CHAN_PROPERTY 8 | |
23 | ||
70eea1bb | 24 | static struct platform_device *rpi_hwmon; |
91f2cf4a | 25 | static struct platform_device *rpi_clk; |
70eea1bb | 26 | |
4e3d6065 EA |
27 | struct rpi_firmware { |
28 | struct mbox_client cl; | |
29 | struct mbox_chan *chan; /* The property channel. */ | |
30 | struct completion c; | |
31 | u32 enabled; | |
1e7c5735 NSJ |
32 | |
33 | struct kref consumers; | |
4e3d6065 EA |
34 | }; |
35 | ||
36 | static DEFINE_MUTEX(transaction_lock); | |
37 | ||
38 | static void response_callback(struct mbox_client *cl, void *msg) | |
39 | { | |
40 | struct rpi_firmware *fw = container_of(cl, struct rpi_firmware, cl); | |
41 | complete(&fw->c); | |
42 | } | |
43 | ||
44 | /* | |
45 | * Sends a request to the firmware through the BCM2835 mailbox driver, | |
46 | * and synchronously waits for the reply. | |
47 | */ | |
48 | static int | |
49 | rpi_firmware_transaction(struct rpi_firmware *fw, u32 chan, u32 data) | |
50 | { | |
51 | u32 message = MBOX_MSG(chan, data); | |
52 | int ret; | |
53 | ||
54 | WARN_ON(data & 0xf); | |
55 | ||
56 | mutex_lock(&transaction_lock); | |
57 | reinit_completion(&fw->c); | |
58 | ret = mbox_send_message(fw->chan, &message); | |
59 | if (ret >= 0) { | |
0829187b SW |
60 | if (wait_for_completion_timeout(&fw->c, HZ)) { |
61 | ret = 0; | |
62 | } else { | |
63 | ret = -ETIMEDOUT; | |
64 | WARN_ONCE(1, "Firmware transaction timeout"); | |
65 | } | |
4e3d6065 EA |
66 | } else { |
67 | dev_err(fw->cl.dev, "mbox_send_message returned %d\n", ret); | |
68 | } | |
69 | mutex_unlock(&transaction_lock); | |
70 | ||
71 | return ret; | |
72 | } | |
73 | ||
74 | /** | |
75 | * rpi_firmware_property_list - Submit firmware property list | |
76 | * @fw: Pointer to firmware structure from rpi_firmware_get(). | |
77 | * @data: Buffer holding tags. | |
78 | * @tag_size: Size of tags buffer. | |
79 | * | |
80 | * Submits a set of concatenated tags to the VPU firmware through the | |
81 | * mailbox property interface. | |
82 | * | |
83 | * The buffer header and the ending tag are added by this function and | |
84 | * don't need to be supplied, just the actual tags for your operation. | |
85 | * See struct rpi_firmware_property_tag_header for the per-tag | |
86 | * structure. | |
87 | */ | |
88 | int rpi_firmware_property_list(struct rpi_firmware *fw, | |
89 | void *data, size_t tag_size) | |
90 | { | |
91 | size_t size = tag_size + 12; | |
92 | u32 *buf; | |
93 | dma_addr_t bus_addr; | |
94 | int ret; | |
95 | ||
96 | /* Packets are processed a dword at a time. */ | |
97 | if (size & 3) | |
98 | return -EINVAL; | |
99 | ||
100 | buf = dma_alloc_coherent(fw->cl.dev, PAGE_ALIGN(size), &bus_addr, | |
101 | GFP_ATOMIC); | |
102 | if (!buf) | |
103 | return -ENOMEM; | |
104 | ||
105 | /* The firmware will error out without parsing in this case. */ | |
106 | WARN_ON(size >= 1024 * 1024); | |
107 | ||
108 | buf[0] = size; | |
109 | buf[1] = RPI_FIRMWARE_STATUS_REQUEST; | |
110 | memcpy(&buf[2], data, tag_size); | |
111 | buf[size / 4 - 1] = RPI_FIRMWARE_PROPERTY_END; | |
112 | wmb(); | |
113 | ||
114 | ret = rpi_firmware_transaction(fw, MBOX_CHAN_PROPERTY, bus_addr); | |
115 | ||
116 | rmb(); | |
117 | memcpy(data, &buf[2], tag_size); | |
118 | if (ret == 0 && buf[1] != RPI_FIRMWARE_STATUS_SUCCESS) { | |
119 | /* | |
120 | * The tag name here might not be the one causing the | |
121 | * error, if there were multiple tags in the request. | |
122 | * But single-tag is the most common, so go with it. | |
123 | */ | |
124 | dev_err(fw->cl.dev, "Request 0x%08x returned status 0x%08x\n", | |
125 | buf[2], buf[1]); | |
126 | ret = -EINVAL; | |
127 | } | |
128 | ||
129 | dma_free_coherent(fw->cl.dev, PAGE_ALIGN(size), buf, bus_addr); | |
130 | ||
131 | return ret; | |
132 | } | |
133 | EXPORT_SYMBOL_GPL(rpi_firmware_property_list); | |
134 | ||
135 | /** | |
136 | * rpi_firmware_property - Submit single firmware property | |
137 | * @fw: Pointer to firmware structure from rpi_firmware_get(). | |
138 | * @tag: One of enum_mbox_property_tag. | |
139 | * @tag_data: Tag data buffer. | |
140 | * @buf_size: Buffer size. | |
141 | * | |
142 | * Submits a single tag to the VPU firmware through the mailbox | |
143 | * property interface. | |
144 | * | |
145 | * This is a convenience wrapper around | |
146 | * rpi_firmware_property_list() to avoid some of the | |
147 | * boilerplate in property calls. | |
148 | */ | |
149 | int rpi_firmware_property(struct rpi_firmware *fw, | |
150 | u32 tag, void *tag_data, size_t buf_size) | |
151 | { | |
91c6ada6 | 152 | struct rpi_firmware_property_tag_header *header; |
4e3d6065 EA |
153 | int ret; |
154 | ||
91c6ada6 JH |
155 | /* Some mailboxes can use over 1k bytes. Rather than checking |
156 | * size and using stack or kmalloc depending on requirements, | |
157 | * just use kmalloc. Mailboxes don't get called enough to worry | |
158 | * too much about the time taken in the allocation. | |
159 | */ | |
160 | void *data = kmalloc(sizeof(*header) + buf_size, GFP_KERNEL); | |
a1547e0b | 161 | |
91c6ada6 JH |
162 | if (!data) |
163 | return -ENOMEM; | |
164 | ||
165 | header = data; | |
4e3d6065 EA |
166 | header->tag = tag; |
167 | header->buf_size = buf_size; | |
168 | header->req_resp_size = 0; | |
91c6ada6 JH |
169 | memcpy(data + sizeof(*header), tag_data, buf_size); |
170 | ||
171 | ret = rpi_firmware_property_list(fw, data, buf_size + sizeof(*header)); | |
172 | ||
173 | memcpy(tag_data, data + sizeof(*header), buf_size); | |
4e3d6065 | 174 | |
91c6ada6 | 175 | kfree(data); |
4e3d6065 EA |
176 | |
177 | return ret; | |
178 | } | |
179 | EXPORT_SYMBOL_GPL(rpi_firmware_property); | |
180 | ||
181 | static void | |
182 | rpi_firmware_print_firmware_revision(struct rpi_firmware *fw) | |
183 | { | |
da785a87 | 184 | time64_t date_and_time; |
4e3d6065 EA |
185 | u32 packet; |
186 | int ret = rpi_firmware_property(fw, | |
187 | RPI_FIRMWARE_GET_FIRMWARE_REVISION, | |
188 | &packet, sizeof(packet)); | |
189 | ||
4a60f58e AS |
190 | if (ret) |
191 | return; | |
4e3d6065 | 192 | |
da785a87 AS |
193 | /* This is not compatible with y2038 */ |
194 | date_and_time = packet; | |
195 | dev_info(fw->cl.dev, "Attached to firmware from %ptT\n", &date_and_time); | |
4e3d6065 EA |
196 | } |
197 | ||
70eea1bb SW |
198 | static void |
199 | rpi_register_hwmon_driver(struct device *dev, struct rpi_firmware *fw) | |
200 | { | |
201 | u32 packet; | |
202 | int ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_THROTTLED, | |
203 | &packet, sizeof(packet)); | |
204 | ||
205 | if (ret) | |
206 | return; | |
207 | ||
208 | rpi_hwmon = platform_device_register_data(dev, "raspberrypi-hwmon", | |
209 | -1, NULL, 0); | |
210 | } | |
211 | ||
91f2cf4a NSJ |
212 | static void rpi_register_clk_driver(struct device *dev) |
213 | { | |
511aba09 MR |
214 | struct device_node *firmware; |
215 | ||
216 | /* | |
217 | * Earlier DTs don't have a node for the firmware clocks but | |
218 | * rely on us creating a platform device by hand. If we do | |
219 | * have a node for the firmware clocks, just bail out here. | |
220 | */ | |
221 | firmware = of_get_compatible_child(dev->of_node, | |
222 | "raspberrypi,firmware-clocks"); | |
223 | if (firmware) { | |
224 | of_node_put(firmware); | |
225 | return; | |
226 | } | |
227 | ||
91f2cf4a NSJ |
228 | rpi_clk = platform_device_register_data(dev, "raspberrypi-clk", |
229 | -1, NULL, 0); | |
230 | } | |
231 | ||
40c31955 MR |
232 | unsigned int rpi_firmware_clk_get_max_rate(struct rpi_firmware *fw, unsigned int id) |
233 | { | |
234 | struct rpi_firmware_clk_rate_request msg = | |
235 | RPI_FIRMWARE_CLK_RATE_REQUEST(id); | |
236 | int ret; | |
237 | ||
238 | ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_MAX_CLOCK_RATE, | |
239 | &msg, sizeof(msg)); | |
240 | if (ret) | |
241 | /* | |
242 | * If our firmware doesn't support that operation, or fails, we | |
243 | * assume the maximum clock rate is absolute maximum we can | |
244 | * store over our type. | |
245 | */ | |
246 | return UINT_MAX; | |
247 | ||
248 | return le32_to_cpu(msg.rate); | |
249 | } | |
250 | EXPORT_SYMBOL_GPL(rpi_firmware_clk_get_max_rate); | |
251 | ||
1e7c5735 NSJ |
252 | static void rpi_firmware_delete(struct kref *kref) |
253 | { | |
254 | struct rpi_firmware *fw = container_of(kref, struct rpi_firmware, | |
255 | consumers); | |
256 | ||
257 | mbox_free_channel(fw->chan); | |
258 | kfree(fw); | |
259 | } | |
260 | ||
261 | void rpi_firmware_put(struct rpi_firmware *fw) | |
262 | { | |
263 | kref_put(&fw->consumers, rpi_firmware_delete); | |
264 | } | |
265 | EXPORT_SYMBOL_GPL(rpi_firmware_put); | |
266 | ||
f663204c NSJ |
267 | static void devm_rpi_firmware_put(void *data) |
268 | { | |
269 | struct rpi_firmware *fw = data; | |
270 | ||
271 | rpi_firmware_put(fw); | |
272 | } | |
273 | ||
4e3d6065 EA |
274 | static int rpi_firmware_probe(struct platform_device *pdev) |
275 | { | |
276 | struct device *dev = &pdev->dev; | |
277 | struct rpi_firmware *fw; | |
278 | ||
1e7c5735 NSJ |
279 | /* |
280 | * Memory will be freed by rpi_firmware_delete() once all users have | |
281 | * released their firmware handles. Don't use devm_kzalloc() here. | |
282 | */ | |
283 | fw = kzalloc(sizeof(*fw), GFP_KERNEL); | |
4e3d6065 EA |
284 | if (!fw) |
285 | return -ENOMEM; | |
286 | ||
287 | fw->cl.dev = dev; | |
288 | fw->cl.rx_callback = response_callback; | |
289 | fw->cl.tx_block = true; | |
290 | ||
291 | fw->chan = mbox_request_channel(&fw->cl, 0); | |
292 | if (IS_ERR(fw->chan)) { | |
293 | int ret = PTR_ERR(fw->chan); | |
7b511616 | 294 | kfree(fw); |
ba54ff1f | 295 | return dev_err_probe(dev, ret, "Failed to get mbox channel\n"); |
4e3d6065 EA |
296 | } |
297 | ||
298 | init_completion(&fw->c); | |
1e7c5735 | 299 | kref_init(&fw->consumers); |
4e3d6065 EA |
300 | |
301 | platform_set_drvdata(pdev, fw); | |
302 | ||
303 | rpi_firmware_print_firmware_revision(fw); | |
70eea1bb | 304 | rpi_register_hwmon_driver(dev, fw); |
91f2cf4a | 305 | rpi_register_clk_driver(dev); |
4e3d6065 EA |
306 | |
307 | return 0; | |
308 | } | |
309 | ||
b80ec7c0 SW |
310 | static void rpi_firmware_shutdown(struct platform_device *pdev) |
311 | { | |
312 | struct rpi_firmware *fw = platform_get_drvdata(pdev); | |
313 | ||
314 | if (!fw) | |
315 | return; | |
316 | ||
317 | rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0); | |
318 | } | |
319 | ||
ffc3c929 | 320 | static void rpi_firmware_remove(struct platform_device *pdev) |
4e3d6065 EA |
321 | { |
322 | struct rpi_firmware *fw = platform_get_drvdata(pdev); | |
323 | ||
70eea1bb SW |
324 | platform_device_unregister(rpi_hwmon); |
325 | rpi_hwmon = NULL; | |
91f2cf4a NSJ |
326 | platform_device_unregister(rpi_clk); |
327 | rpi_clk = NULL; | |
1e7c5735 NSJ |
328 | |
329 | rpi_firmware_put(fw); | |
4e3d6065 EA |
330 | } |
331 | ||
bc63897b MR |
332 | static const struct of_device_id rpi_firmware_of_match[] = { |
333 | { .compatible = "raspberrypi,bcm2835-firmware", }, | |
334 | {}, | |
335 | }; | |
336 | MODULE_DEVICE_TABLE(of, rpi_firmware_of_match); | |
337 | ||
338 | struct device_node *rpi_firmware_find_node(void) | |
339 | { | |
340 | return of_find_matching_node(NULL, rpi_firmware_of_match); | |
341 | } | |
342 | EXPORT_SYMBOL_GPL(rpi_firmware_find_node); | |
343 | ||
4e3d6065 EA |
344 | /** |
345 | * rpi_firmware_get - Get pointer to rpi_firmware structure. | |
346 | * @firmware_node: Pointer to the firmware Device Tree node. | |
347 | * | |
1e7c5735 NSJ |
348 | * The reference to rpi_firmware has to be released with rpi_firmware_put(). |
349 | * | |
4e3d6065 EA |
350 | * Returns NULL is the firmware device is not ready. |
351 | */ | |
352 | struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node) | |
353 | { | |
354 | struct platform_device *pdev = of_find_device_by_node(firmware_node); | |
1e7c5735 | 355 | struct rpi_firmware *fw; |
4e3d6065 EA |
356 | |
357 | if (!pdev) | |
358 | return NULL; | |
359 | ||
1e7c5735 NSJ |
360 | fw = platform_get_drvdata(pdev); |
361 | if (!fw) | |
09cbd1df | 362 | goto err_put_device; |
1e7c5735 NSJ |
363 | |
364 | if (!kref_get_unless_zero(&fw->consumers)) | |
09cbd1df CJ |
365 | goto err_put_device; |
366 | ||
367 | put_device(&pdev->dev); | |
1e7c5735 NSJ |
368 | |
369 | return fw; | |
09cbd1df CJ |
370 | |
371 | err_put_device: | |
372 | put_device(&pdev->dev); | |
373 | return NULL; | |
4e3d6065 EA |
374 | } |
375 | EXPORT_SYMBOL_GPL(rpi_firmware_get); | |
376 | ||
f663204c NSJ |
377 | /** |
378 | * devm_rpi_firmware_get - Get pointer to rpi_firmware structure. | |
a21ecc52 | 379 | * @dev: The firmware device structure |
f663204c NSJ |
380 | * @firmware_node: Pointer to the firmware Device Tree node. |
381 | * | |
382 | * Returns NULL is the firmware device is not ready. | |
383 | */ | |
384 | struct rpi_firmware *devm_rpi_firmware_get(struct device *dev, | |
385 | struct device_node *firmware_node) | |
386 | { | |
387 | struct rpi_firmware *fw; | |
388 | ||
389 | fw = rpi_firmware_get(firmware_node); | |
390 | if (!fw) | |
391 | return NULL; | |
392 | ||
393 | if (devm_add_action_or_reset(dev, devm_rpi_firmware_put, fw)) | |
394 | return NULL; | |
395 | ||
396 | return fw; | |
397 | } | |
398 | EXPORT_SYMBOL_GPL(devm_rpi_firmware_get); | |
399 | ||
4e3d6065 EA |
400 | static struct platform_driver rpi_firmware_driver = { |
401 | .driver = { | |
402 | .name = "raspberrypi-firmware", | |
403 | .of_match_table = rpi_firmware_of_match, | |
404 | }, | |
405 | .probe = rpi_firmware_probe, | |
b80ec7c0 | 406 | .shutdown = rpi_firmware_shutdown, |
ffc3c929 | 407 | .remove_new = rpi_firmware_remove, |
4e3d6065 EA |
408 | }; |
409 | module_platform_driver(rpi_firmware_driver); | |
410 | ||
411 | MODULE_AUTHOR("Eric Anholt <eric@anholt.net>"); | |
412 | MODULE_DESCRIPTION("Raspberry Pi firmware driver"); | |
413 | MODULE_LICENSE("GPL v2"); |