diff options
Diffstat (limited to 'drivers/accel/drm_accel.c')
| -rw-r--r-- | drivers/accel/drm_accel.c | 208 |
1 files changed, 208 insertions, 0 deletions
diff --git a/drivers/accel/drm_accel.c b/drivers/accel/drm_accel.c new file mode 100644 index 000000000000..ca3357acd127 --- /dev/null +++ b/drivers/accel/drm_accel.c @@ -0,0 +1,208 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * Copyright 2022 HabanaLabs, Ltd. + * All Rights Reserved. + * + */ + +#include <linux/debugfs.h> +#include <linux/device.h> +#include <linux/xarray.h> + +#include <drm/drm_accel.h> +#include <drm/drm_auth.h> +#include <drm/drm_debugfs.h> +#include <drm/drm_drv.h> +#include <drm/drm_file.h> +#include <drm/drm_ioctl.h> +#include <drm/drm_print.h> + +DEFINE_XARRAY_ALLOC(accel_minors_xa); + +static const struct device_type accel_sysfs_device_minor = { + .name = "accel_minor" +}; + +static char *accel_devnode(const struct device *dev, umode_t *mode) +{ + return kasprintf(GFP_KERNEL, "accel/%s", dev_name(dev)); +} + +static const struct class accel_class = { + .name = "accel", + .devnode = accel_devnode, +}; + +static int accel_sysfs_init(void) +{ + return class_register(&accel_class); +} + +static void accel_sysfs_destroy(void) +{ + class_unregister(&accel_class); +} + +static int accel_name_info(struct seq_file *m, void *data) +{ + struct drm_info_node *node = (struct drm_info_node *) m->private; + struct drm_minor *minor = node->minor; + struct drm_device *dev = minor->dev; + struct drm_master *master; + + mutex_lock(&dev->master_mutex); + master = dev->master; + seq_printf(m, "%s", dev->driver->name); + if (dev->dev) + seq_printf(m, " dev=%s", dev_name(dev->dev)); + if (master && master->unique) + seq_printf(m, " master=%s", master->unique); + if (dev->unique) + seq_printf(m, " unique=%s", dev->unique); + seq_puts(m, "\n"); + mutex_unlock(&dev->master_mutex); + + return 0; +} + +static const struct drm_info_list accel_debugfs_list[] = { + {"name", accel_name_info, 0} +}; +#define ACCEL_DEBUGFS_ENTRIES ARRAY_SIZE(accel_debugfs_list) + +/** + * accel_debugfs_register() - Register debugfs for device + * @dev: Pointer to the device instance. + * + * Creates common files for accelerators. + */ +void accel_debugfs_register(struct drm_device *dev) +{ + struct drm_minor *minor = dev->accel; + + minor->debugfs_root = dev->debugfs_root; + + drm_debugfs_create_files(accel_debugfs_list, ACCEL_DEBUGFS_ENTRIES, + dev->debugfs_root, minor); +} + +/** + * accel_set_device_instance_params() - Set some device parameters for accel device + * @kdev: Pointer to the device instance. + * @index: The minor's index + * + * This function creates the dev_t of the device using the accel major and + * the device's minor number. In addition, it sets the class and type of the + * device instance to the accel sysfs class and device type, respectively. + */ +void accel_set_device_instance_params(struct device *kdev, int index) +{ + kdev->devt = MKDEV(ACCEL_MAJOR, index); + kdev->class = &accel_class; + kdev->type = &accel_sysfs_device_minor; +} + +/** + * accel_open - open method for ACCEL file + * @inode: device inode + * @filp: file pointer. + * + * This function must be used by drivers as their &file_operations.open method. + * It looks up the correct ACCEL device and instantiates all the per-file + * resources for it. It also calls the &drm_driver.open driver callback. + * + * Return: 0 on success or negative errno value on failure. + */ +int accel_open(struct inode *inode, struct file *filp) +{ + struct drm_device *dev; + struct drm_minor *minor; + int retcode; + + minor = drm_minor_acquire(&accel_minors_xa, iminor(inode)); + if (IS_ERR(minor)) + return PTR_ERR(minor); + + dev = minor->dev; + + atomic_fetch_inc(&dev->open_count); + + /* share address_space across all char-devs of a single device */ + filp->f_mapping = dev->anon_inode->i_mapping; + + retcode = drm_open_helper(filp, minor); + if (retcode) + goto err_undo; + + return 0; + +err_undo: + atomic_dec(&dev->open_count); + drm_minor_release(minor); + return retcode; +} +EXPORT_SYMBOL_GPL(accel_open); + +static int accel_stub_open(struct inode *inode, struct file *filp) +{ + const struct file_operations *new_fops; + struct drm_minor *minor; + int err; + + minor = drm_minor_acquire(&accel_minors_xa, iminor(inode)); + if (IS_ERR(minor)) + return PTR_ERR(minor); + + new_fops = fops_get(minor->dev->driver->fops); + if (!new_fops) { + err = -ENODEV; + goto out; + } + + replace_fops(filp, new_fops); + if (filp->f_op->open) + err = filp->f_op->open(inode, filp); + else + err = 0; + +out: + drm_minor_release(minor); + + return err; +} + +static const struct file_operations accel_stub_fops = { + .owner = THIS_MODULE, + .open = accel_stub_open, + .llseek = noop_llseek, +}; + +void accel_core_exit(void) +{ + unregister_chrdev(ACCEL_MAJOR, "accel"); + accel_sysfs_destroy(); + WARN_ON(!xa_empty(&accel_minors_xa)); +} + +int __init accel_core_init(void) +{ + int ret; + + ret = accel_sysfs_init(); + if (ret < 0) { + DRM_ERROR("Cannot create ACCEL class: %d\n", ret); + goto error; + } + + ret = register_chrdev(ACCEL_MAJOR, "accel", &accel_stub_fops); + if (ret < 0) + DRM_ERROR("Cannot register ACCEL major: %d\n", ret); + +error: + /* + * Any cleanup due to errors will be done in drm_core_exit() that + * will call accel_core_exit() + */ + return ret; +} |