Loading...
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Defines interfaces for interacting wtih the Raspberry Pi firmware's
4 * property channel.
5 *
6 * Copyright © 2015 Broadcom
7 */
8
9#include <linux/dma-mapping.h>
10#include <linux/mailbox_client.h>
11#include <linux/module.h>
12#include <linux/of_platform.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15#include <linux/pci.h>
16#include <linux/delay.h>
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
24#define VL805_PCI_CONFIG_VERSION_OFFSET 0x50
25
26static struct platform_device *rpi_hwmon;
27static struct platform_device *rpi_clk;
28
29struct rpi_firmware {
30 struct mbox_client cl;
31 struct mbox_chan *chan; /* The property channel. */
32 struct completion c;
33 u32 enabled;
34};
35
36static DEFINE_MUTEX(transaction_lock);
37
38static 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 */
48static int
49rpi_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) {
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 }
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 */
88int 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}
133EXPORT_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 */
149int rpi_firmware_property(struct rpi_firmware *fw,
150 u32 tag, void *tag_data, size_t buf_size)
151{
152 struct rpi_firmware_property_tag_header *header;
153 int ret;
154
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);
161
162 if (!data)
163 return -ENOMEM;
164
165 header = data;
166 header->tag = tag;
167 header->buf_size = buf_size;
168 header->req_resp_size = 0;
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);
174
175 kfree(data);
176
177 return ret;
178}
179EXPORT_SYMBOL_GPL(rpi_firmware_property);
180
181static void
182rpi_firmware_print_firmware_revision(struct rpi_firmware *fw)
183{
184 time64_t date_and_time;
185 u32 packet;
186 int ret = rpi_firmware_property(fw,
187 RPI_FIRMWARE_GET_FIRMWARE_REVISION,
188 &packet, sizeof(packet));
189
190 if (ret)
191 return;
192
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);
196}
197
198static void
199rpi_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
212static void rpi_register_clk_driver(struct device *dev)
213{
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
228 rpi_clk = platform_device_register_data(dev, "raspberrypi-clk",
229 -1, NULL, 0);
230}
231
232static int rpi_firmware_probe(struct platform_device *pdev)
233{
234 struct device *dev = &pdev->dev;
235 struct rpi_firmware *fw;
236
237 fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL);
238 if (!fw)
239 return -ENOMEM;
240
241 fw->cl.dev = dev;
242 fw->cl.rx_callback = response_callback;
243 fw->cl.tx_block = true;
244
245 fw->chan = mbox_request_channel(&fw->cl, 0);
246 if (IS_ERR(fw->chan)) {
247 int ret = PTR_ERR(fw->chan);
248 if (ret != -EPROBE_DEFER)
249 dev_err(dev, "Failed to get mbox channel: %d\n", ret);
250 return ret;
251 }
252
253 init_completion(&fw->c);
254
255 platform_set_drvdata(pdev, fw);
256
257 rpi_firmware_print_firmware_revision(fw);
258 rpi_register_hwmon_driver(dev, fw);
259 rpi_register_clk_driver(dev);
260
261 return 0;
262}
263
264static void rpi_firmware_shutdown(struct platform_device *pdev)
265{
266 struct rpi_firmware *fw = platform_get_drvdata(pdev);
267
268 if (!fw)
269 return;
270
271 rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0);
272}
273
274static int rpi_firmware_remove(struct platform_device *pdev)
275{
276 struct rpi_firmware *fw = platform_get_drvdata(pdev);
277
278 platform_device_unregister(rpi_hwmon);
279 rpi_hwmon = NULL;
280 platform_device_unregister(rpi_clk);
281 rpi_clk = NULL;
282 mbox_free_channel(fw->chan);
283
284 return 0;
285}
286
287/**
288 * rpi_firmware_get - Get pointer to rpi_firmware structure.
289 * @firmware_node: Pointer to the firmware Device Tree node.
290 *
291 * Returns NULL is the firmware device is not ready.
292 */
293struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node)
294{
295 struct platform_device *pdev = of_find_device_by_node(firmware_node);
296
297 if (!pdev)
298 return NULL;
299
300 return platform_get_drvdata(pdev);
301}
302EXPORT_SYMBOL_GPL(rpi_firmware_get);
303
304/*
305 * The Raspberry Pi 4 gets its USB functionality from VL805, a PCIe chip that
306 * implements xHCI. After a PCI reset, VL805's firmware may either be loaded
307 * directly from an EEPROM or, if not present, by the SoC's co-processor,
308 * VideoCore. RPi4's VideoCore OS contains both the non public firmware load
309 * logic and the VL805 firmware blob. This function triggers the aforementioned
310 * process.
311 */
312int rpi_firmware_init_vl805(struct pci_dev *pdev)
313{
314 struct device_node *fw_np;
315 struct rpi_firmware *fw;
316 u32 dev_addr, version;
317 int ret;
318
319 fw_np = of_find_compatible_node(NULL, NULL,
320 "raspberrypi,bcm2835-firmware");
321 if (!fw_np)
322 return 0;
323
324 fw = rpi_firmware_get(fw_np);
325 of_node_put(fw_np);
326 if (!fw)
327 return -ENODEV;
328
329 /*
330 * Make sure we don't trigger a firmware load unnecessarily.
331 *
332 * If something went wrong with PCI, this whole exercise would be
333 * futile as VideoCore expects from us a configured PCI bus. Just take
334 * the faulty version (likely ~0) and let xHCI's registration fail
335 * further down the line.
336 */
337 pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET, &version);
338 if (version)
339 goto exit;
340
341 dev_addr = pdev->bus->number << 20 | PCI_SLOT(pdev->devfn) << 15 |
342 PCI_FUNC(pdev->devfn) << 12;
343
344 ret = rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_XHCI_RESET,
345 &dev_addr, sizeof(dev_addr));
346 if (ret)
347 return ret;
348
349 /* Wait for vl805 to startup */
350 usleep_range(200, 1000);
351
352 pci_read_config_dword(pdev, VL805_PCI_CONFIG_VERSION_OFFSET,
353 &version);
354exit:
355 pci_info(pdev, "VL805 firmware version %08x\n", version);
356
357 return 0;
358}
359EXPORT_SYMBOL_GPL(rpi_firmware_init_vl805);
360
361static const struct of_device_id rpi_firmware_of_match[] = {
362 { .compatible = "raspberrypi,bcm2835-firmware", },
363 {},
364};
365MODULE_DEVICE_TABLE(of, rpi_firmware_of_match);
366
367static struct platform_driver rpi_firmware_driver = {
368 .driver = {
369 .name = "raspberrypi-firmware",
370 .of_match_table = rpi_firmware_of_match,
371 },
372 .probe = rpi_firmware_probe,
373 .shutdown = rpi_firmware_shutdown,
374 .remove = rpi_firmware_remove,
375};
376module_platform_driver(rpi_firmware_driver);
377
378MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
379MODULE_DESCRIPTION("Raspberry Pi firmware driver");
380MODULE_LICENSE("GPL v2");
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Defines interfaces for interacting wtih the Raspberry Pi firmware's
4 * property channel.
5 *
6 * Copyright © 2015 Broadcom
7 */
8
9#include <linux/dma-mapping.h>
10#include <linux/mailbox_client.h>
11#include <linux/module.h>
12#include <linux/of_platform.h>
13#include <linux/platform_device.h>
14#include <linux/slab.h>
15#include <soc/bcm2835/raspberrypi-firmware.h>
16
17#define MBOX_MSG(chan, data28) (((data28) & ~0xf) | ((chan) & 0xf))
18#define MBOX_CHAN(msg) ((msg) & 0xf)
19#define MBOX_DATA28(msg) ((msg) & ~0xf)
20#define MBOX_CHAN_PROPERTY 8
21
22static struct platform_device *rpi_hwmon;
23static struct platform_device *rpi_clk;
24
25struct rpi_firmware {
26 struct mbox_client cl;
27 struct mbox_chan *chan; /* The property channel. */
28 struct completion c;
29 u32 enabled;
30};
31
32static DEFINE_MUTEX(transaction_lock);
33
34static void response_callback(struct mbox_client *cl, void *msg)
35{
36 struct rpi_firmware *fw = container_of(cl, struct rpi_firmware, cl);
37 complete(&fw->c);
38}
39
40/*
41 * Sends a request to the firmware through the BCM2835 mailbox driver,
42 * and synchronously waits for the reply.
43 */
44static int
45rpi_firmware_transaction(struct rpi_firmware *fw, u32 chan, u32 data)
46{
47 u32 message = MBOX_MSG(chan, data);
48 int ret;
49
50 WARN_ON(data & 0xf);
51
52 mutex_lock(&transaction_lock);
53 reinit_completion(&fw->c);
54 ret = mbox_send_message(fw->chan, &message);
55 if (ret >= 0) {
56 if (wait_for_completion_timeout(&fw->c, HZ)) {
57 ret = 0;
58 } else {
59 ret = -ETIMEDOUT;
60 WARN_ONCE(1, "Firmware transaction timeout");
61 }
62 } else {
63 dev_err(fw->cl.dev, "mbox_send_message returned %d\n", ret);
64 }
65 mutex_unlock(&transaction_lock);
66
67 return ret;
68}
69
70/**
71 * rpi_firmware_property_list - Submit firmware property list
72 * @fw: Pointer to firmware structure from rpi_firmware_get().
73 * @data: Buffer holding tags.
74 * @tag_size: Size of tags buffer.
75 *
76 * Submits a set of concatenated tags to the VPU firmware through the
77 * mailbox property interface.
78 *
79 * The buffer header and the ending tag are added by this function and
80 * don't need to be supplied, just the actual tags for your operation.
81 * See struct rpi_firmware_property_tag_header for the per-tag
82 * structure.
83 */
84int rpi_firmware_property_list(struct rpi_firmware *fw,
85 void *data, size_t tag_size)
86{
87 size_t size = tag_size + 12;
88 u32 *buf;
89 dma_addr_t bus_addr;
90 int ret;
91
92 /* Packets are processed a dword at a time. */
93 if (size & 3)
94 return -EINVAL;
95
96 buf = dma_alloc_coherent(fw->cl.dev, PAGE_ALIGN(size), &bus_addr,
97 GFP_ATOMIC);
98 if (!buf)
99 return -ENOMEM;
100
101 /* The firmware will error out without parsing in this case. */
102 WARN_ON(size >= 1024 * 1024);
103
104 buf[0] = size;
105 buf[1] = RPI_FIRMWARE_STATUS_REQUEST;
106 memcpy(&buf[2], data, tag_size);
107 buf[size / 4 - 1] = RPI_FIRMWARE_PROPERTY_END;
108 wmb();
109
110 ret = rpi_firmware_transaction(fw, MBOX_CHAN_PROPERTY, bus_addr);
111
112 rmb();
113 memcpy(data, &buf[2], tag_size);
114 if (ret == 0 && buf[1] != RPI_FIRMWARE_STATUS_SUCCESS) {
115 /*
116 * The tag name here might not be the one causing the
117 * error, if there were multiple tags in the request.
118 * But single-tag is the most common, so go with it.
119 */
120 dev_err(fw->cl.dev, "Request 0x%08x returned status 0x%08x\n",
121 buf[2], buf[1]);
122 ret = -EINVAL;
123 }
124
125 dma_free_coherent(fw->cl.dev, PAGE_ALIGN(size), buf, bus_addr);
126
127 return ret;
128}
129EXPORT_SYMBOL_GPL(rpi_firmware_property_list);
130
131/**
132 * rpi_firmware_property - Submit single firmware property
133 * @fw: Pointer to firmware structure from rpi_firmware_get().
134 * @tag: One of enum_mbox_property_tag.
135 * @tag_data: Tag data buffer.
136 * @buf_size: Buffer size.
137 *
138 * Submits a single tag to the VPU firmware through the mailbox
139 * property interface.
140 *
141 * This is a convenience wrapper around
142 * rpi_firmware_property_list() to avoid some of the
143 * boilerplate in property calls.
144 */
145int rpi_firmware_property(struct rpi_firmware *fw,
146 u32 tag, void *tag_data, size_t buf_size)
147{
148 struct rpi_firmware_property_tag_header *header;
149 int ret;
150
151 /* Some mailboxes can use over 1k bytes. Rather than checking
152 * size and using stack or kmalloc depending on requirements,
153 * just use kmalloc. Mailboxes don't get called enough to worry
154 * too much about the time taken in the allocation.
155 */
156 void *data = kmalloc(sizeof(*header) + buf_size, GFP_KERNEL);
157
158 if (!data)
159 return -ENOMEM;
160
161 header = data;
162 header->tag = tag;
163 header->buf_size = buf_size;
164 header->req_resp_size = 0;
165 memcpy(data + sizeof(*header), tag_data, buf_size);
166
167 ret = rpi_firmware_property_list(fw, data, buf_size + sizeof(*header));
168
169 memcpy(tag_data, data + sizeof(*header), buf_size);
170
171 kfree(data);
172
173 return ret;
174}
175EXPORT_SYMBOL_GPL(rpi_firmware_property);
176
177static void
178rpi_firmware_print_firmware_revision(struct rpi_firmware *fw)
179{
180 u32 packet;
181 int ret = rpi_firmware_property(fw,
182 RPI_FIRMWARE_GET_FIRMWARE_REVISION,
183 &packet, sizeof(packet));
184
185 if (ret == 0) {
186 struct tm tm;
187
188 time64_to_tm(packet, 0, &tm);
189
190 dev_info(fw->cl.dev,
191 "Attached to firmware from %04ld-%02d-%02d %02d:%02d\n",
192 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
193 tm.tm_hour, tm.tm_min);
194 }
195}
196
197static void
198rpi_register_hwmon_driver(struct device *dev, struct rpi_firmware *fw)
199{
200 u32 packet;
201 int ret = rpi_firmware_property(fw, RPI_FIRMWARE_GET_THROTTLED,
202 &packet, sizeof(packet));
203
204 if (ret)
205 return;
206
207 rpi_hwmon = platform_device_register_data(dev, "raspberrypi-hwmon",
208 -1, NULL, 0);
209}
210
211static void rpi_register_clk_driver(struct device *dev)
212{
213 rpi_clk = platform_device_register_data(dev, "raspberrypi-clk",
214 -1, NULL, 0);
215}
216
217static int rpi_firmware_probe(struct platform_device *pdev)
218{
219 struct device *dev = &pdev->dev;
220 struct rpi_firmware *fw;
221
222 fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL);
223 if (!fw)
224 return -ENOMEM;
225
226 fw->cl.dev = dev;
227 fw->cl.rx_callback = response_callback;
228 fw->cl.tx_block = true;
229
230 fw->chan = mbox_request_channel(&fw->cl, 0);
231 if (IS_ERR(fw->chan)) {
232 int ret = PTR_ERR(fw->chan);
233 if (ret != -EPROBE_DEFER)
234 dev_err(dev, "Failed to get mbox channel: %d\n", ret);
235 return ret;
236 }
237
238 init_completion(&fw->c);
239
240 platform_set_drvdata(pdev, fw);
241
242 rpi_firmware_print_firmware_revision(fw);
243 rpi_register_hwmon_driver(dev, fw);
244 rpi_register_clk_driver(dev);
245
246 return 0;
247}
248
249static void rpi_firmware_shutdown(struct platform_device *pdev)
250{
251 struct rpi_firmware *fw = platform_get_drvdata(pdev);
252
253 if (!fw)
254 return;
255
256 rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0);
257}
258
259static int rpi_firmware_remove(struct platform_device *pdev)
260{
261 struct rpi_firmware *fw = platform_get_drvdata(pdev);
262
263 platform_device_unregister(rpi_hwmon);
264 rpi_hwmon = NULL;
265 platform_device_unregister(rpi_clk);
266 rpi_clk = NULL;
267 mbox_free_channel(fw->chan);
268
269 return 0;
270}
271
272/**
273 * rpi_firmware_get - Get pointer to rpi_firmware structure.
274 * @firmware_node: Pointer to the firmware Device Tree node.
275 *
276 * Returns NULL is the firmware device is not ready.
277 */
278struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node)
279{
280 struct platform_device *pdev = of_find_device_by_node(firmware_node);
281
282 if (!pdev)
283 return NULL;
284
285 return platform_get_drvdata(pdev);
286}
287EXPORT_SYMBOL_GPL(rpi_firmware_get);
288
289static const struct of_device_id rpi_firmware_of_match[] = {
290 { .compatible = "raspberrypi,bcm2835-firmware", },
291 {},
292};
293MODULE_DEVICE_TABLE(of, rpi_firmware_of_match);
294
295static struct platform_driver rpi_firmware_driver = {
296 .driver = {
297 .name = "raspberrypi-firmware",
298 .of_match_table = rpi_firmware_of_match,
299 },
300 .probe = rpi_firmware_probe,
301 .shutdown = rpi_firmware_shutdown,
302 .remove = rpi_firmware_remove,
303};
304module_platform_driver(rpi_firmware_driver);
305
306MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
307MODULE_DESCRIPTION("Raspberry Pi firmware driver");
308MODULE_LICENSE("GPL v2");