aboutsummaryrefslogtreecommitdiffstats
path: root/target/linux/bcm27xx/patches-5.4/950-0279-drivers-char-add-chardev-for-mmap-ing-the-RPiVid-con.patch
blob: 3f3c5ea148d1649af89886fa962a49d31aa94c0c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
From dcf515d36ce574edd773c9c6321b6bbf9724e209 Mon Sep 17 00:00:00 2001
From: Jonathan Bell <jonathan@raspberrypi.org>
Date: Thu, 9 May 2019 14:30:37 +0100
Subject: [PATCH] drivers: char: add chardev for mmap'ing the RPiVid
 control registers

Based on the gpiomem driver, allow mapping of the decoder register
spaces such that userspace can access control/status registers.
This driver is intended for use with a custom ffmpeg backend accelerator
prior to a v4l2 driver being written.

Signed-off-by: Jonathan Bell <jonathan@raspberrypi.org>
---
 drivers/char/broadcom/Kconfig      |   8 +
 drivers/char/broadcom/Makefile     |   1 +
 drivers/char/broadcom/rpivid-mem.c | 286 +++++++++++++++++++++++++++++
 drivers/mfd/bcm2835-pm.c           |  12 +-
 drivers/soc/bcm/bcm2835-power.c    |   6 +-
 include/linux/mfd/bcm2835-pm.h     |   2 +-
 6 files changed, 305 insertions(+), 10 deletions(-)
 create mode 100644 drivers/char/broadcom/rpivid-mem.c

--- a/drivers/char/broadcom/Kconfig
+++ b/drivers/char/broadcom/Kconfig
@@ -49,3 +49,11 @@ config BCM2835_SMI_DEV
 		This driver provides a character device interface (ioctl + read/write) to
 		Broadcom's Secondary Memory interface. The low-level functionality is provided
 		by the SMI driver itself.
+
+config RPIVID_MEM
+	tristate "Character device driver for the Raspberry Pi RPIVid video decoder hardware"
+	default n
+	help
+		This driver provides a character device interface for memory-map operations
+		so userspace tools can access the control and status registers of the
+		Raspberry Pi RPiVid video decoder hardware.
--- a/drivers/char/broadcom/Makefile
+++ b/drivers/char/broadcom/Makefile
@@ -4,3 +4,4 @@ obj-$(CONFIG_BCM_VC_SM)         += vc_sm
 
 obj-$(CONFIG_BCM2835_DEVGPIOMEM)+= bcm2835-gpiomem.o
 obj-$(CONFIG_BCM2835_SMI_DEV)	+= bcm2835_smi_dev.o
+obj-$(CONFIG_RPIVID_MEM)	+= rpivid-mem.o
--- /dev/null
+++ b/drivers/char/broadcom/rpivid-mem.c
@@ -0,0 +1,286 @@
+/**
+ * rpivid-mem.c - character device access to the RPiVid decoder registers
+ *
+ * Based on bcm2835-gpiomem.c. Provides IO memory access to the decoder
+ * register blocks such that ffmpeg plugins can access the hardware.
+ *
+ * Jonathan Bell <jonathan@raspberrypi.org>
+ * Copyright (c) 2019, Raspberry Pi (Trading) Ltd.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions, and the following disclaimer,
+ *    without modification.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. The names of the above-listed copyright holders may not be used
+ *    to endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * ALTERNATIVELY, this software may be distributed under the terms of the
+ * GNU General Public License ("GPL") version 2, as published by the Free
+ * Software Foundation.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+ * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
+ * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+ * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+ * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/cdev.h>
+#include <linux/pagemap.h>
+#include <linux/io.h>
+
+#define DRIVER_NAME "rpivid-mem"
+#define DEVICE_MINOR 0
+
+struct rpivid_mem_priv {
+	dev_t devid;
+	struct class *class;
+	struct cdev rpivid_mem_cdev;
+	unsigned long regs_phys;
+	unsigned long mem_window_len;
+	struct device *dev;
+	const char *name;
+};
+
+static int rpivid_mem_open(struct inode *inode, struct file *file)
+{
+	int dev = iminor(inode);
+	int ret = 0;
+	struct rpivid_mem_priv *priv;
+	if (dev != DEVICE_MINOR && dev != DEVICE_MINOR + 1)
+		ret = -ENXIO;
+
+	priv = container_of(inode->i_cdev, struct rpivid_mem_priv,
+				rpivid_mem_cdev);
+	if (!priv)
+		return -EINVAL;
+	file->private_data = priv;
+	return ret;
+}
+
+static int rpivid_mem_release(struct inode *inode, struct file *file)
+{
+	int dev = iminor(inode);
+	int ret = 0;
+
+	if (dev != DEVICE_MINOR && dev != DEVICE_MINOR + 1)
+		ret = -ENXIO;
+
+	return ret;
+}
+
+static const struct vm_operations_struct rpivid_mem_vm_ops = {
+#ifdef CONFIG_HAVE_IOREMAP_PROT
+	.access = generic_access_phys
+#endif
+};
+
+static int rpivid_mem_mmap(struct file *file, struct vm_area_struct *vma)
+{
+	struct rpivid_mem_priv *priv;
+	unsigned long pages;
+
+	priv = file->private_data;
+	pages = priv->regs_phys >> PAGE_SHIFT;
+	/*
+	 * The address decode is far larger than the actual number of registers.
+	 * Just map the whole lot in.
+	 */
+	vma->vm_page_prot = phys_mem_access_prot(file, pages,
+						 priv->mem_window_len,
+						 vma->vm_page_prot);
+	vma->vm_ops = &rpivid_mem_vm_ops;
+	if (remap_pfn_range(vma, vma->vm_start,
+			pages,
+			priv->mem_window_len,
+			vma->vm_page_prot)) {
+		return -EAGAIN;
+	}
+	return 0;
+}
+
+static const struct file_operations
+rpivid_mem_fops = {
+	.owner = THIS_MODULE,
+	.open = rpivid_mem_open,
+	.release = rpivid_mem_release,
+	.mmap = rpivid_mem_mmap,
+};
+
+static const struct of_device_id rpivid_mem_of_match[];
+static int rpivid_mem_probe(struct platform_device *pdev)
+{
+	int err;
+	void *ptr_err;
+	const struct of_device_id *id;
+	struct device *dev = &pdev->dev;
+	struct device *rpivid_mem_dev;
+	struct resource *ioresource;
+	struct rpivid_mem_priv *priv;
+
+
+	/* Allocate buffers and instance data */
+
+	priv = kzalloc(sizeof(struct rpivid_mem_priv), GFP_KERNEL);
+
+	if (!priv) {
+		err = -ENOMEM;
+		goto failed_inst_alloc;
+	}
+	platform_set_drvdata(pdev, priv);
+
+	priv->dev = dev;
+	id = of_match_device(rpivid_mem_of_match, dev);
+	if (!id)
+		return -EINVAL;
+	priv->name = id->data;
+
+	ioresource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (ioresource) {
+		priv->regs_phys = ioresource->start;
+		priv->mem_window_len = ioresource->end - ioresource->start;
+	} else {
+		dev_err(priv->dev, "failed to get IO resource");
+		err = -ENOENT;
+		goto failed_get_resource;
+	}
+
+	/* Create character device entries */
+
+	err = alloc_chrdev_region(&priv->devid,
+				  DEVICE_MINOR, 2, priv->name);
+	if (err != 0) {
+		dev_err(priv->dev, "unable to allocate device number");
+		goto failed_alloc_chrdev;
+	}
+	cdev_init(&priv->rpivid_mem_cdev, &rpivid_mem_fops);
+	priv->rpivid_mem_cdev.owner = THIS_MODULE;
+	err = cdev_add(&priv->rpivid_mem_cdev, priv->devid, 2);
+	if (err != 0) {
+		dev_err(priv->dev, "unable to register device");
+		goto failed_cdev_add;
+	}
+
+	/* Create sysfs entries */
+
+	priv->class = class_create(THIS_MODULE, priv->name);
+	ptr_err = priv->class;
+	if (IS_ERR(ptr_err))
+		goto failed_class_create;
+
+	rpivid_mem_dev = device_create(priv->class, NULL,
+					priv->devid, NULL,
+					priv->name);
+	ptr_err = rpivid_mem_dev;
+	if (IS_ERR(ptr_err))
+		goto failed_device_create;
+
+	/* Legacy alias */
+	{
+		char *oldname = kstrdup(priv->name, GFP_KERNEL);
+
+		oldname[1] = 'a';
+		oldname[2] = 'r';
+		oldname[3] = 'g';
+		oldname[4] = 'o';
+		oldname[5] = 'n';
+		(void)device_create(priv->class, NULL, priv->devid + 1, NULL,
+				       oldname + 1);
+		kfree(oldname);
+	}
+
+	dev_info(priv->dev, "%s initialised: Registers at 0x%08lx length 0x%08lx",
+		priv->name, priv->regs_phys, priv->mem_window_len);
+
+	return 0;
+
+failed_device_create:
+	class_destroy(priv->class);
+failed_class_create:
+	cdev_del(&priv->rpivid_mem_cdev);
+	err = PTR_ERR(ptr_err);
+failed_cdev_add:
+	unregister_chrdev_region(priv->devid, 1);
+failed_alloc_chrdev:
+failed_get_resource:
+	kfree(priv);
+failed_inst_alloc:
+	dev_err(priv->dev, "could not load rpivid_mem");
+	return err;
+}
+
+static int rpivid_mem_remove(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct rpivid_mem_priv *priv = platform_get_drvdata(pdev);
+
+	device_destroy(priv->class, priv->devid);
+	class_destroy(priv->class);
+	cdev_del(&priv->rpivid_mem_cdev);
+	unregister_chrdev_region(priv->devid, 1);
+	kfree(priv);
+
+	dev_info(dev, "%s driver removed - OK", priv->name);
+	return 0;
+}
+
+static const struct of_device_id rpivid_mem_of_match[] = {
+	{
+		.compatible = "raspberrypi,rpivid-hevc-decoder",
+		.data = "rpivid-hevcmem",
+	},
+	{
+		.compatible = "raspberrypi,rpivid-h264-decoder",
+		.data = "rpivid-h264mem",
+	},
+	{
+		.compatible = "raspberrypi,rpivid-vp9-decoder",
+		.data = "rpivid-vp9mem",
+	},
+	/* The "intc" is included as this block of hardware contains the
+	 * "frame done" status flags.
+	 */
+	{
+		.compatible = "raspberrypi,rpivid-local-intc",
+		.data = "rpivid-intcmem",
+	},
+	{ /* sentinel */ },
+};
+
+MODULE_DEVICE_TABLE(of, rpivid_mem_of_match);
+
+static struct platform_driver rpivid_mem_driver = {
+	.probe = rpivid_mem_probe,
+	.remove = rpivid_mem_remove,
+	.driver = {
+		   .name = DRIVER_NAME,
+		   .owner = THIS_MODULE,
+		   .of_match_table = rpivid_mem_of_match,
+		   },
+};
+
+module_platform_driver(rpivid_mem_driver);
+
+MODULE_ALIAS("platform:rpivid-mem");
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("Driver for accessing RPiVid decoder registers from userspace");
+MODULE_AUTHOR("Jonathan Bell <jonathan@raspberrypi.org>");
--- a/drivers/mfd/bcm2835-pm.c
+++ b/drivers/mfd/bcm2835-pm.c
@@ -50,14 +50,14 @@ static int bcm2835_pm_probe(struct platf
 	if (ret)
 		return ret;
 
-	/* Map the ARGON ASB regs if present. */
+	/* Map the RPiVid ASB regs if present. */
 	res = platform_get_resource(pdev, IORESOURCE_MEM, 2);
 	if (res) {
-		pm->arg_asb = devm_ioremap_resource(dev, res);
-		if (IS_ERR(pm->arg_asb)) {
-			dev_err(dev, "Failed to map ARGON ASB: %ld\n",
-				PTR_ERR(pm->arg_asb));
-			return PTR_ERR(pm->arg_asb);
+		pm->rpivid_asb = devm_ioremap_resource(dev, res);
+		if (IS_ERR(pm->rpivid_asb)) {
+			dev_err(dev, "Failed to map RPiVid ASB: %ld\n",
+				PTR_ERR(pm->rpivid_asb));
+			return PTR_ERR(pm->rpivid_asb);
 		}
 	}
 
--- a/drivers/soc/bcm/bcm2835-power.c
+++ b/drivers/soc/bcm/bcm2835-power.c
@@ -637,15 +637,15 @@ static int bcm2835_power_probe(struct pl
 	power->base = pm->base;
 	power->asb = pm->asb;
 
-	/* 2711 hack: the new ARGON ASB took over V3D, which is our
+	/* 2711 hack: the new RPiVid ASB took over V3D, which is our
 	 * only consumer of this driver so far.  The old ASB seems to
 	 * still be present with ISP and H264 bits but no V3D, but I
 	 * don't know if that's real or not.  The V3D is in the same
 	 * place in the new ASB as the old one, so just poke the new
 	 * one for now.
 	 */
-	if (pm->arg_asb) {
-		power->asb = pm->arg_asb;
+	if (pm->rpivid_asb) {
+		power->asb = pm->rpivid_asb;
 		power->is_2711 = true;
 	}
 
--- a/include/linux/mfd/bcm2835-pm.h
+++ b/include/linux/mfd/bcm2835-pm.h
@@ -9,7 +9,7 @@ struct bcm2835_pm {
 	struct device *dev;
 	void __iomem *base;
 	void __iomem *asb;
-	void __iomem *arg_asb;
+	void __iomem *rpivid_asb;
 };
 
 #endif /* BCM2835_MFD_PM_H */