linux_dsm_epyc7002/drivers/gpu/drm/vkms/vkms_drv.c

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/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
/**
* DOC: vkms (Virtual Kernel Modesetting)
*
* vkms is a software-only model of a kms driver that is useful for testing,
* or for running X (or similar) on headless machines and be able to still
* use the GPU. vkms aims to enable a virtual display without the need for
* a hardware display capability.
*/
#include <linux/module.h>
#include <drm/drm_gem.h>
#include <drm/drm_crtc_helper.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_fb_helper.h>
#include "vkms_drv.h"
#define DRIVER_NAME "vkms"
#define DRIVER_DESC "Virtual Kernel Mode Setting"
#define DRIVER_DATE "20180514"
#define DRIVER_MAJOR 1
#define DRIVER_MINOR 0
static struct vkms_device *vkms_device;
bool enable_cursor;
module_param_named(enable_cursor, enable_cursor, bool, 0444);
MODULE_PARM_DESC(enable_cursor, "Enable/Disable cursor support");
static const struct file_operations vkms_driver_fops = {
.owner = THIS_MODULE,
.open = drm_open,
.mmap = drm_gem_mmap,
.unlocked_ioctl = drm_ioctl,
.compat_ioctl = drm_compat_ioctl,
.poll = drm_poll,
.read = drm_read,
.llseek = no_llseek,
.release = drm_release,
};
static const struct vm_operations_struct vkms_gem_vm_ops = {
.fault = vkms_gem_fault,
.open = drm_gem_vm_open,
.close = drm_gem_vm_close,
};
static void vkms_release(struct drm_device *dev)
{
struct vkms_device *vkms = container_of(dev, struct vkms_device, drm);
platform_device_unregister(vkms->platform);
drm_atomic_helper_shutdown(&vkms->drm);
drm_mode_config_cleanup(&vkms->drm);
drm_dev_fini(&vkms->drm);
drm/vkms: Implement CRC debugfs API This patch implement the necessary functions to compute and add CRCs entries: - Implement the set_crc_source() callback. - Compute CRC using crc32 on the visible part of the framebuffer. - Use ordered workqueue per output to compute and add CRC at the end of a vblank. - Use appropriate synchronization methods since the CRC computation must be atomic wrt the generated vblank event for a given atomic update, by using spinlock across atomic_begin/atomic_flush to wrap the event handling code completely and match the flip event with the CRC. Since vkms_crc_work_handle() can sleep, spinlock can't be acquired while accessing vkms_output->primary_crc to compute CRC. To make sure the data is updated and released without conflict with the vkms_crc_work_handle(), the work_struct is flushed @crtc_destroy and the data is updated before scheduling the work handle again, as follow: * CRC data update: 1- store vkms_crc_data {fb, src} per plane_state 2- @plane_duplicate_state -> allocate vkms_crc_data 3- during atomic commit (@atomic_update) -> a) copy {fb, src} to plane_state->crc_data b) get reference to fb, 3- @plane_destroy_state -> a) if (fb refcount) remove reference to fb b) deallocate crc_data * Atomic Commit: 1- vkms_plane_atomic_check 2- vkms_prepare_fb -> vmap vkms_gem_obj->vaddr 3- atomic_begin -> hold crc spinlock 4- atomic_plane_update -> a) update vkms_output->primary_crc b) get reference to fb 5- atomic_flush -> a) send vblank event while holding event_lock b) release crc spinlock * hrtimer regular callback: 1- hold crc spinlock 2- drm_crtc_handle_vblank() 3- queue vkms_crc_work_handle 4- release crc spinlock * cleanup: 1- @cleanup_fb ->vunmap vkms_gem_obj->vaddr 2- @crtc_destroy -> flush work struct 3- @plane_destroy -> a) if (fb refcount) remove reference to fb b) deallocate crc_data Signed-off-by: Haneen Mohammed <hamohammed.sa@gmail.com> [seanpaul fixed typo in vkms_crtc s/vblamk/vblank/] Signed-off-by: Sean Paul <seanpaul@chromium.org> Link: https://patchwork.freedesktop.org/patch/msgid/b948327f48c3e70ab232b4a0848ee6d033b26484.1533171495.git.hamohammed.sa@gmail.com
2018-08-02 08:10:26 +07:00
destroy_workqueue(vkms->output.crc_workq);
}
static struct drm_driver vkms_driver = {
.driver_features = DRIVER_MODESET | DRIVER_ATOMIC | DRIVER_GEM,
.release = vkms_release,
.fops = &vkms_driver_fops,
.dumb_create = vkms_dumb_create,
.gem_vm_ops = &vkms_gem_vm_ops,
.gem_free_object_unlocked = vkms_gem_free_object,
.get_vblank_timestamp = vkms_get_vblank_timestamp,
.name = DRIVER_NAME,
.desc = DRIVER_DESC,
.date = DRIVER_DATE,
.major = DRIVER_MAJOR,
.minor = DRIVER_MINOR,
};
static const struct drm_mode_config_funcs vkms_mode_funcs = {
.fb_create = drm_gem_fb_create,
.atomic_check = drm_atomic_helper_check,
.atomic_commit = drm_atomic_helper_commit,
};
static int vkms_modeset_init(struct vkms_device *vkmsdev)
{
struct drm_device *dev = &vkmsdev->drm;
drm_mode_config_init(dev);
dev->mode_config.funcs = &vkms_mode_funcs;
dev->mode_config.min_width = XRES_MIN;
dev->mode_config.min_height = YRES_MIN;
dev->mode_config.max_width = XRES_MAX;
dev->mode_config.max_height = YRES_MAX;
return vkms_output_init(vkmsdev);
}
static int __init vkms_init(void)
{
int ret;
vkms_device = kzalloc(sizeof(*vkms_device), GFP_KERNEL);
if (!vkms_device)
return -ENOMEM;
vkms_device->platform =
platform_device_register_simple(DRIVER_NAME, -1, NULL, 0);
if (IS_ERR(vkms_device->platform)) {
ret = PTR_ERR(vkms_device->platform);
goto out_free;
}
ret = drm_dev_init(&vkms_device->drm, &vkms_driver,
&vkms_device->platform->dev);
if (ret)
goto out_unregister;
vkms_device->drm.irq_enabled = true;
ret = drm_vblank_init(&vkms_device->drm, 1);
if (ret) {
DRM_ERROR("Failed to vblank\n");
goto out_fini;
}
ret = vkms_modeset_init(vkms_device);
if (ret)
goto out_fini;
ret = drm_dev_register(&vkms_device->drm, 0);
if (ret)
goto out_fini;
return 0;
out_fini:
drm_dev_fini(&vkms_device->drm);
out_unregister:
platform_device_unregister(vkms_device->platform);
out_free:
kfree(vkms_device);
return ret;
}
static void __exit vkms_exit(void)
{
if (!vkms_device) {
DRM_INFO("vkms_device is NULL.\n");
return;
}
drm_dev_unregister(&vkms_device->drm);
drm_dev_put(&vkms_device->drm);
kfree(vkms_device);
}
module_init(vkms_init);
module_exit(vkms_exit);
MODULE_AUTHOR("Haneen Mohammed <hamohammed.sa@gmail.com>");
MODULE_AUTHOR("Rodrigo Siqueira <rodrigosiqueiramelo@gmail.com>");
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");