forked from ~ljy/RK356X_SDK_RELEASE

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hc
2024-02-20 102a0743326a03cd1a1202ceda21e175b7d3575c 
 kernel/drivers/firmware/raspberrypi.c
....@@ -1,15 +1,13 @@
1
+// SPDX-License-Identifier: GPL-2.0
12 /*
23  * Defines interfaces for interacting wtih the Raspberry Pi firmware's
34  * property channel.
45  *
56  * Copyright © 2015 Broadcom
6
- *
7
- * This program is free software; you can redistribute it and/or modify
8
- * it under the terms of the GNU General Public License version 2 as
9
- * published by the Free Software Foundation.
107  */
118 
129 #include <linux/dma-mapping.h>
10
+#include <linux/kref.h>
1311 #include <linux/mailbox_client.h>
1412 #include <linux/module.h>
1513 #include <linux/of_platform.h>
....@@ -23,12 +21,15 @@
2321 #define MBOX_CHAN_PROPERTY		8
2422 
2523 static struct platform_device *rpi_hwmon;
24
+static struct platform_device *rpi_clk;
2625 
2726 struct rpi_firmware {
2827 	struct mbox_client cl;
2928 	struct mbox_chan *chan; /* The property channel. */
3029 	struct completion c;
3130 	u32 enabled;
31
+
32
+	struct kref consumers;
3233 };
3334 
3435 static DEFINE_MUTEX(transaction_lock);
....@@ -55,8 +56,12 @@
5556 	reinit_completion(&fw->c);
5657 	ret = mbox_send_message(fw->chan, &message);
5758 	if (ret >= 0) {
58
-		wait_for_completion(&fw->c);
59
-		ret = 0;
59
+		if (wait_for_completion_timeout(&fw->c, HZ)) {
60
+			ret = 0;
61
+		} else {
62
+			ret = -ETIMEDOUT;
63
+			WARN_ONCE(1, "Firmware transaction timeout");
64
+		}
6065 	} else {
6166 		dev_err(fw->cl.dev, "mbox_send_message returned %d\n", ret);
6267 	}
....@@ -175,21 +180,18 @@
175180 static void
176181 rpi_firmware_print_firmware_revision(struct rpi_firmware *fw)
177182 {
183
+	time64_t date_and_time;
178184 	u32 packet;
179185 	int ret = rpi_firmware_property(fw,
180186 					RPI_FIRMWARE_GET_FIRMWARE_REVISION,
181187 					&packet, sizeof(packet));
182188 
183
-	if (ret == 0) {
184
-		struct tm tm;
189
+	if (ret)
190
+		return;
185191 
186
-		time64_to_tm(packet, 0, &tm);
187
-
188
-		dev_info(fw->cl.dev,
189
-			 "Attached to firmware from %04ld-%02d-%02d %02d:%02d\n",
190
-			 tm.tm_year + 1900, tm.tm_mon + 1, tm.tm_mday,
191
-			 tm.tm_hour, tm.tm_min);
192
-	}
192
+	/* This is not compatible with y2038 */
193
+	date_and_time = packet;
194
+	dev_info(fw->cl.dev, "Attached to firmware from %ptT\n", &date_and_time);
193195 }
194196 
195197 static void
....@@ -206,12 +208,58 @@
206208 						  -1, NULL, 0);
207209 }
208210 
211
+static void rpi_register_clk_driver(struct device *dev)
212
+{
213
+	struct device_node *firmware;
214
+
215
+	/*
216
+	 * Earlier DTs don't have a node for the firmware clocks but
217
+	 * rely on us creating a platform device by hand. If we do
218
+	 * have a node for the firmware clocks, just bail out here.
219
+	 */
220
+	firmware = of_get_compatible_child(dev->of_node,
221
+					   "raspberrypi,firmware-clocks");
222
+	if (firmware) {
223
+		of_node_put(firmware);
224
+		return;
225
+	}
226
+
227
+	rpi_clk = platform_device_register_data(dev, "raspberrypi-clk",
228
+						-1, NULL, 0);
229
+}
230
+
231
+static void rpi_firmware_delete(struct kref *kref)
232
+{
233
+	struct rpi_firmware *fw = container_of(kref, struct rpi_firmware,
234
+					       consumers);
235
+
236
+	mbox_free_channel(fw->chan);
237
+	kfree(fw);
238
+}
239
+
240
+void rpi_firmware_put(struct rpi_firmware *fw)
241
+{
242
+	kref_put(&fw->consumers, rpi_firmware_delete);
243
+}
244
+EXPORT_SYMBOL_GPL(rpi_firmware_put);
245
+
246
+static void devm_rpi_firmware_put(void *data)
247
+{
248
+	struct rpi_firmware *fw = data;
249
+
250
+	rpi_firmware_put(fw);
251
+}
252
+
209253 static int rpi_firmware_probe(struct platform_device *pdev)
210254 {
211255 	struct device *dev = &pdev->dev;
212256 	struct rpi_firmware *fw;
213257 
214
-	fw = devm_kzalloc(dev, sizeof(*fw), GFP_KERNEL);
258
+	/*
259
+	 * Memory will be freed by rpi_firmware_delete() once all users have
260
+	 * released their firmware handles. Don't use devm_kzalloc() here.
261
+	 */
262
+	fw = kzalloc(sizeof(*fw), GFP_KERNEL);
215263 	if (!fw)
216264 		return -ENOMEM;
217265 
....@@ -224,17 +272,30 @@
224272 		int ret = PTR_ERR(fw->chan);
225273 		if (ret != -EPROBE_DEFER)
226274 			dev_err(dev, "Failed to get mbox channel: %d\n", ret);
275
+		kfree(fw);
227276 		return ret;
228277 	}
229278 
230279 	init_completion(&fw->c);
280
+	kref_init(&fw->consumers);
231281 
232282 	platform_set_drvdata(pdev, fw);
233283 
234284 	rpi_firmware_print_firmware_revision(fw);
235285 	rpi_register_hwmon_driver(dev, fw);
286
+	rpi_register_clk_driver(dev);
236287 
237288 	return 0;
289
+}
290
+
291
+static void rpi_firmware_shutdown(struct platform_device *pdev)
292
+{
293
+	struct rpi_firmware *fw = platform_get_drvdata(pdev);
294
+
295
+	if (!fw)
296
+		return;
297
+
298
+	rpi_firmware_property(fw, RPI_FIRMWARE_NOTIFY_REBOOT, NULL, 0);
238299 }
239300 
240301 static int rpi_firmware_remove(struct platform_device *pdev)
....@@ -243,7 +304,10 @@
243304 
244305 	platform_device_unregister(rpi_hwmon);
245306 	rpi_hwmon = NULL;
246
-	mbox_free_channel(fw->chan);
307
+	platform_device_unregister(rpi_clk);
308
+	rpi_clk = NULL;
309
+
310
+	rpi_firmware_put(fw);
247311 
248312 	return 0;
249313 }
....@@ -252,18 +316,56 @@
252316  * rpi_firmware_get - Get pointer to rpi_firmware structure.
253317  * @firmware_node:    Pointer to the firmware Device Tree node.
254318  *
319
+ * The reference to rpi_firmware has to be released with rpi_firmware_put().
320
+ *
255321  * Returns NULL is the firmware device is not ready.
256322  */
257323 struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node)
258324 {
259325 	struct platform_device *pdev = of_find_device_by_node(firmware_node);
326
+	struct rpi_firmware *fw;
260327 
261328 	if (!pdev)
262329 		return NULL;
263330 
264
-	return platform_get_drvdata(pdev);
331
+	fw = platform_get_drvdata(pdev);
332
+	if (!fw)
333
+		goto err_put_device;
334
+
335
+	if (!kref_get_unless_zero(&fw->consumers))
336
+		goto err_put_device;
337
+
338
+	put_device(&pdev->dev);
339
+
340
+	return fw;
341
+
342
+err_put_device:
343
+	put_device(&pdev->dev);
344
+	return NULL;
265345 }
266346 EXPORT_SYMBOL_GPL(rpi_firmware_get);
347
+
348
+/**
349
+ * devm_rpi_firmware_get - Get pointer to rpi_firmware structure.
350
+ * @firmware_node:    Pointer to the firmware Device Tree node.
351
+ *
352
+ * Returns NULL is the firmware device is not ready.
353
+ */
354
+struct rpi_firmware *devm_rpi_firmware_get(struct device *dev,
355
+					   struct device_node *firmware_node)
356
+{
357
+	struct rpi_firmware *fw;
358
+
359
+	fw = rpi_firmware_get(firmware_node);
360
+	if (!fw)
361
+		return NULL;
362
+
363
+	if (devm_add_action_or_reset(dev, devm_rpi_firmware_put, fw))
364
+		return NULL;
365
+
366
+	return fw;
367
+}
368
+EXPORT_SYMBOL_GPL(devm_rpi_firmware_get);
267369 
268370 static const struct of_device_id rpi_firmware_of_match[] = {
269371 	{ .compatible = "raspberrypi,bcm2835-firmware", },
....@@ -277,6 +379,7 @@
277379 		.of_match_table = rpi_firmware_of_match,
278380 	},
279381 	.probe		= rpi_firmware_probe,
382
+	.shutdown	= rpi_firmware_shutdown,
280383 	.remove		= rpi_firmware_remove,
281384 };
282385 module_platform_driver(rpi_firmware_driver);