+++ /dev/null
-From 0be0d6439128366a8d2ac0afaf88f19209171e51 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 Argon 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/argon-mem.c | 277 ++++++++++++++++++++++++++++++
- 3 files changed, 286 insertions(+)
- create mode 100644 drivers/char/broadcom/argon-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 ARGON_MEM
-+ tristate "Character device driver for the Argon 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 Argon
-+ 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_ARGON_MEM) += argon-mem.o
---- /dev/null
-+++ b/drivers/char/broadcom/argon-mem.c
-@@ -0,0 +1,277 @@
-+/**
-+ * argon-mem.c - character device access to the Argon 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 "argon-mem"
-+#define DEVICE_MINOR 0
-+
-+struct argon_mem_priv {
-+ dev_t devid;
-+ struct class *class;
-+ struct cdev argon_mem_cdev;
-+ unsigned long regs_phys;
-+ unsigned long mem_window_len;
-+ struct device *dev;
-+ const char *name;
-+};
-+
-+static int argon_mem_open(struct inode *inode, struct file *file)
-+{
-+ int dev = iminor(inode);
-+ int ret = 0;
-+ struct argon_mem_priv *priv;
-+ if (dev != DEVICE_MINOR)
-+ ret = -ENXIO;
-+
-+ priv = container_of(inode->i_cdev, struct argon_mem_priv,
-+ argon_mem_cdev);
-+ if (!priv)
-+ return -EINVAL;
-+ file->private_data = priv;
-+ return ret;
-+}
-+
-+static int argon_mem_release(struct inode *inode, struct file *file)
-+{
-+ int dev = iminor(inode);
-+ int ret = 0;
-+
-+ if (dev != DEVICE_MINOR)
-+ ret = -ENXIO;
-+
-+ return ret;
-+}
-+
-+static const struct vm_operations_struct argon_mem_vm_ops = {
-+#ifdef CONFIG_HAVE_IOREMAP_PROT
-+ .access = generic_access_phys
-+#endif
-+};
-+
-+static int argon_mem_mmap(struct file *file, struct vm_area_struct *vma)
-+{
-+ struct argon_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 = &argon_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
-+argon_mem_fops = {
-+ .owner = THIS_MODULE,
-+ .open = argon_mem_open,
-+ .release = argon_mem_release,
-+ .mmap = argon_mem_mmap,
-+};
-+
-+static const struct of_device_id argon_mem_of_match[];
-+static int argon_mem_probe(struct platform_device *pdev)
-+{
-+ int err;
-+ void *ptr_err;
-+ const struct of_device_id *id;
-+ struct device *dev = &pdev->dev;
-+ struct device *argon_mem_dev;
-+ struct resource *ioresource;
-+ struct argon_mem_priv *priv;
-+
-+
-+ /* Allocate buffers and instance data */
-+
-+ priv = kzalloc(sizeof(struct argon_mem_priv), GFP_KERNEL);
-+
-+ if (!priv) {
-+ err = -ENOMEM;
-+ goto failed_inst_alloc;
-+ }
-+ platform_set_drvdata(pdev, priv);
-+
-+ priv->dev = dev;
-+ id = of_match_device(argon_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, 1, priv->name);
-+ if (err != 0) {
-+ dev_err(priv->dev, "unable to allocate device number");
-+ goto failed_alloc_chrdev;
-+ }
-+ cdev_init(&priv->argon_mem_cdev, &argon_mem_fops);
-+ priv->argon_mem_cdev.owner = THIS_MODULE;
-+ err = cdev_add(&priv->argon_mem_cdev, priv->devid, 1);
-+ 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;
-+
-+ argon_mem_dev = device_create(priv->class, NULL,
-+ priv->devid, NULL,
-+ priv->name);
-+ ptr_err = argon_mem_dev;
-+ if (IS_ERR(ptr_err))
-+ goto failed_device_create;
-+
-+ 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->argon_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 argon_mem");
-+ return err;
-+}
-+
-+static int argon_mem_remove(struct platform_device *pdev)
-+{
-+ struct device *dev = &pdev->dev;
-+ struct argon_mem_priv *priv = platform_get_drvdata(pdev);
-+
-+ device_destroy(priv->class, priv->devid);
-+ class_destroy(priv->class);
-+ cdev_del(&priv->argon_mem_cdev);
-+ unregister_chrdev_region(priv->devid, 1);
-+ kfree(priv);
-+
-+ dev_info(dev, "%s driver removed - OK", priv->name);
-+ return 0;
-+}
-+
-+static const char argon_hevc_name[] = "argon-hevcmem";
-+static const char argon_h264_name[] = "argon-h264mem";
-+static const char argon_vp9_name[] = "argon-vp9mem";
-+static const char argon_intc_name[] = "argon-intcmem";
-+
-+static const struct of_device_id argon_mem_of_match[] = {
-+ {
-+ .compatible = "raspberrypi,argon-hevc-decoder",
-+ .data = &argon_hevc_name,
-+ },
-+ {
-+ .compatible = "raspberrypi,argon-h264-decoder",
-+ .data = &argon_h264_name,
-+ },
-+ {
-+ .compatible = "raspberrypi,argon-vp9-decoder",
-+ .data = &argon_vp9_name,
-+ },
-+ /* The "intc" is included as this block of hardware contains the
-+ * "frame done" status flags.
-+ */
-+ {
-+ .compatible = "raspberrypi,argon-local-intc",
-+ .data = &argon_intc_name,
-+ },
-+ { /* sentinel */ },
-+};
-+
-+MODULE_DEVICE_TABLE(of, argon_mem_of_match);
-+
-+static struct platform_driver argon_mem_driver = {
-+ .probe = argon_mem_probe,
-+ .remove = argon_mem_remove,
-+ .driver = {
-+ .name = DRIVER_NAME,
-+ .owner = THIS_MODULE,
-+ .of_match_table = argon_mem_of_match,
-+ },
-+};
-+
-+module_platform_driver(argon_mem_driver);
-+
-+MODULE_ALIAS("platform:argon-mem");
-+MODULE_LICENSE("GPL");
-+MODULE_DESCRIPTION("Driver for accessing Argon decoder registers from userspace");
-+MODULE_AUTHOR("Jonathan Bell <jonathan@raspberrypi.org>");
projects / openwrt / openwrt.git / blobdiff