[PATH 1/4] drm: Add Virtual DRM device driver
Sam Ravnborg
sam at ravnborg.org
Mon Jun 21 15:55:17 UTC 2021
Hi Tomohito
On Mon, Jun 21, 2021 at 03:44:00PM +0900, Tomohito Esaki wrote:
> Virtual DRM splits the resources of an overlay plane into multiple
> virtual devices to allow each plane to be accessed by each process.
>
> This makes it possible to overlay images output from multiple processes
> on a display. For example, one process displays the camera image without
> compositor while another process overlays the compositor's drawing of
> the UI.
>
> The virtual DRM creates standalone virtual device and make DRM planes
> from a master device (e.g. card0) accessible via one or more virtual
> devices. However, these plane are no longer accessible from the original
> device.
> Each virtual device (and plane) can be accessed via a separate
> device file.
>
> Signed-off-by: Tomohito Esaki <etom at igel.co.jp>
> ---
> drivers/gpu/drm/Kconfig | 7 +
> drivers/gpu/drm/Makefile | 1 +
> drivers/gpu/drm/vdrm/vdrm_api.h | 68 +++
> drivers/gpu/drm/vdrm/vdrm_drv.c | 859 ++++++++++++++++++++++++++++++++
> drivers/gpu/drm/vdrm/vdrm_drv.h | 80 +++
Plase consider making the header files self-contained.
So there are no hdden dependencies between the two.
Use forward declarations rahter than including header files is possible.
A few trivial comments in the following. I did not try to follow all the
functionality of the driver and I expect others to comment on the idea.
Sam
> 5 files changed, 1015 insertions(+)
> create mode 100644 drivers/gpu/drm/vdrm/vdrm_api.h
> create mode 100644 drivers/gpu/drm/vdrm/vdrm_drv.c
> create mode 100644 drivers/gpu/drm/vdrm/vdrm_drv.h
>
> diff --git a/drivers/gpu/drm/Kconfig b/drivers/gpu/drm/Kconfig
> index 3c16bd1afd87..ba7f4eeab385 100644
> --- a/drivers/gpu/drm/Kconfig
> +++ b/drivers/gpu/drm/Kconfig
> @@ -294,6 +294,13 @@ config DRM_VKMS
>
> If M is selected the module will be called vkms.
>
> +config DRM_VDRM
> + tristate "Virtual DRM"
> + depends on DRM
> + help
> + Virtual DRM splits the resources of an overlay plane into multiple
> + virtual devices to allow each plane to be accessed by each process.
Could you look into pulling a bit more info here. You made a very nice
intro to the patch, consider using it in the help text too.
> +
> source "drivers/gpu/drm/exynos/Kconfig"
>
> source "drivers/gpu/drm/rockchip/Kconfig"
> diff --git a/drivers/gpu/drm/Makefile b/drivers/gpu/drm/Makefile
> index 5279db4392df..55dbf85e2579 100644
> --- a/drivers/gpu/drm/Makefile
> +++ b/drivers/gpu/drm/Makefile
> @@ -82,6 +82,7 @@ obj-$(CONFIG_DRM_VMWGFX)+= vmwgfx/
> obj-$(CONFIG_DRM_VIA) +=via/
> obj-$(CONFIG_DRM_VGEM) += vgem/
> obj-$(CONFIG_DRM_VKMS) += vkms/
> +obj-$(CONFIG_DRM_VDRM) += vdrm/
Alphabetic order (mostly) so before vgem/
> obj-$(CONFIG_DRM_NOUVEAU) +=nouveau/
> obj-$(CONFIG_DRM_EXYNOS) +=exynos/
> obj-$(CONFIG_DRM_ROCKCHIP) +=rockchip/
> diff --git a/drivers/gpu/drm/vdrm/vdrm_api.h b/drivers/gpu/drm/vdrm/vdrm_api.h
> new file mode 100644
> index 000000000000..dd4d7e774800
> --- /dev/null
> +++ b/drivers/gpu/drm/vdrm/vdrm_api.h
> @@ -0,0 +1,68 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * vdrm_api.h -- Virtual DRM API
> + *
> + * Copyright (C) 2021 Renesas Electronics Corporation
> + */
> +
> +#ifndef __VDRM_API__
> +#define __VDRM_API__
> +
> +#include <linux/of_device.h>
> +#include <drm/drm_crtc.h>
> +
> +/**
> + * struct vdrm_property_info - Information about the properties passed from
> + * the DRM driver to vDRM
> + * @prop: Parent property to pass to vDRM
> + * @default_val: Default value for the property passed to vDRM
> + */
> +struct vdrm_property_info {
> + struct drm_property *prop;
> + uint64_t default_val;
> +};
It would be nice that all structs used inline comments - and then you
are consistent too.
> +
> +/**
> + * struct vdrm_funcs - Callbacks to parent DRM driver
> + */
> +struct vdrm_funcs {
> + /**
> + * @dumb_create:
> + *
> + * Called by &drm_driver.dumb_create. Please read the documentation
> + * for the &drm_driver.dumb_create hook for more details.
> + */
> + int (*dumb_create)(struct drm_file *file, struct drm_device *dev,
> + struct drm_mode_create_dumb *args);
> +
> + /**
> + * @crtc_flush:
> + *
> + * Called by &drm_crtc_helper_funcs.atomic_flush. Please read the
> + * documentation for the &drm_crtc_helper_funcs.atomic_flush hook for
> + * more details.
> + */
> + void (*crtc_flush)(struct drm_crtc *crtc);
> +};
> +
> +struct vdrm_device;
> +struct vdrm_display;
> +
> +void vdrm_drv_handle_vblank(struct vdrm_display *vdisplay);
> +void vdrm_drv_finish_page_flip(struct vdrm_display *vdisplay);
> +struct vdrm_device *vdrm_drv_init(struct drm_device *dev,
> + struct device_node *np, int num_props,
> + struct vdrm_property_info *props,
> + const struct vdrm_funcs *funcs);
> +int vdrm_drv_plane_init(struct vdrm_device *vdrm, struct drm_plane *plane,
> + const struct drm_plane_funcs *funcs,
> + const struct drm_plane_helper_funcs *helper_funcs,
> + const u32 *formats, unsigned int num_formats,
> + int max_zpos);
> +struct vdrm_display *vdrm_drv_display_init(struct vdrm_device *vdrm,
> + struct drm_crtc *crtc,
> + struct drm_plane *plane);
> +int vdrm_drv_register(struct vdrm_device *vdrm);
> +void vdrm_drv_fini(struct vdrm_device *vdrm);
> +
> +#endif /* __VDRM_API__ */
> diff --git a/drivers/gpu/drm/vdrm/vdrm_drv.c b/drivers/gpu/drm/vdrm/vdrm_drv.c
> new file mode 100644
> index 000000000000..835bdecfc8e6
> --- /dev/null
> +++ b/drivers/gpu/drm/vdrm/vdrm_drv.c
> @@ -0,0 +1,859 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * vdrm_drv.c -- Virtual DRM driver
> + *
> + * Copyright (C) 2021 Renesas Electronics Corporation
> + *
> + * This driver is based on drivers/gpu/drm/drm_simple_kms_helper.c.
> + */
> +
> +#include <linux/of_device.h>
> +#include <drm/drm_atomic.h>
> +#include <drm/drm_atomic_helper.h>
> +#include <drm/drm_atomic_uapi.h>
> +#include <drm/drm_fb_cma_helper.h>
> +#include <drm/drm_fb_helper.h>
> +#include <drm/drm_drv.h>
> +#include <drm/drm_gem_cma_helper.h>
> +#include <drm/drm_plane_helper.h>
> +#include <drm/drm_probe_helper.h>
> +#include <drm/drm_vblank.h>
> +#include <drm/drm_gem_framebuffer_helper.h>
> +#include <video/videomode.h>
> +
> +#include "vdrm_drv.h"
> +
> +static inline struct vdrm_display *
> +to_vdrm_display(struct drm_connector *connector)
> +{
> + return container_of(connector, struct vdrm_display, connector);
> +}
> +
> +static inline struct vdrm_display *
> +crtc_to_vdrm_display(struct drm_crtc *crtc)
> +{
> + return container_of(crtc, struct vdrm_display, crtc);
> +}
> +
> +static int vdrm_dumb_create(struct drm_file *file, struct drm_device *dev,
> + struct drm_mode_create_dumb *args)
> +{
> + struct vdrm_device *vdrm = to_vdrm_device(dev);
> +
> + return vdrm->funcs->dumb_create(file, dev, args);
> +}
> +
> +struct vdrm_framebuffer {
> + struct drm_framebuffer fb;
> + struct drm_framebuffer *parent_fb;
> +};
> +
> +static inline struct vdrm_framebuffer *
> +to_vdrm_framebuffer(struct drm_framebuffer *fb)
> +{
> + return container_of(fb, struct vdrm_framebuffer, fb);
> +}
> +
> +static void vdrm_fb_destroy(struct drm_framebuffer *fb)
> +{
> + struct vdrm_framebuffer *vfb = to_vdrm_framebuffer(fb);
> +
> + vfb->parent_fb->funcs->destroy(vfb->parent_fb);
> + drm_framebuffer_cleanup(fb);
> + kfree(vfb);
> +}
> +
> +static const struct drm_framebuffer_funcs vdrm_fb_funcs = {
> + .destroy = vdrm_fb_destroy,
> +};
> +
> +static int vdrm_fb_init(struct drm_device *dev, struct vdrm_framebuffer *vfb)
> +{
> + vfb->fb = *vfb->parent_fb;
> + vfb->fb.dev = dev;
> +
> + return drm_framebuffer_init(dev, &vfb->fb, &vdrm_fb_funcs);
> +}
> +
> +static struct drm_framebuffer *
> +vdrm_fb_create(struct drm_device *dev, struct drm_file *file_priv,
> + const struct drm_mode_fb_cmd2 *mode_cmd)
> +{
> + struct vdrm_device *vdrm = to_vdrm_device(dev);
> + const struct drm_mode_config_funcs *mode_config_funcs =
> + vdrm->parent->mode_config.funcs;
> + struct vdrm_framebuffer *vfb;
> + struct drm_framebuffer *fb;
> + int ret;
> +
> + vfb = kzalloc(sizeof(*vfb), GFP_KERNEL);
> + if (!vfb)
> + return ERR_PTR(-ENOMEM);
> +
> + fb = mode_config_funcs->fb_create(vdrm->parent, file_priv, mode_cmd);
> + if (IS_ERR(fb)) {
> + kfree(vfb);
> + return fb;
> + }
> +
> + vfb->parent_fb = fb;
> + ret = vdrm_fb_init(dev, vfb);
> + if (ret) {
> + fb->funcs->destroy(fb);
> + kfree(vfb);
> + return ERR_PTR(ret);
> + }
> +
> + return &vfb->fb;
> +}
> +
> +static const struct drm_mode_config_funcs vdrm_mode_config_funcs = {
> + .fb_create = vdrm_fb_create,
> + .atomic_check = drm_atomic_helper_check,
> + .atomic_commit = drm_atomic_helper_commit,
> +};
> +
> +static struct drm_display_mode *vdrm_create_mode(struct vdrm_display *disp)
> +{
> + struct drm_display_mode *mode;
> + struct videomode videomode;
> +
> + mode = drm_mode_create(&disp->dev->ddev);
> + if (!mode)
> + return NULL;
> +
> + memset(&videomode, 0, sizeof(videomode));
> + videomode.hactive = disp->plane_info.width;
> + videomode.vactive = disp->plane_info.height;
> + videomode.pixelclock =
> + disp->parent_crtc->state->adjusted_mode.crtc_clock * 1000;
> + mode->type = DRM_MODE_TYPE_PREFERRED | DRM_MODE_TYPE_DRIVER;
> + drm_display_mode_from_videomode(&videomode, mode);
> +
If you create a drm_display_mode here then you can loose the videomode
dependency. And I do not need to tell you that a Kconfig dependency is missing
to use videomode. Do not forget to drop the include.
> + return mode;
> +}
> +
> +static int vdrm_connector_get_mode(struct drm_connector *connector)
> +{
> + struct vdrm_display *disp = to_vdrm_display(connector);
> + struct drm_display_mode *mode = vdrm_create_mode(disp);
> +
> + if (!mode)
> + return 0;
> +
> + drm_mode_probed_add(connector, mode);
> + return 1;
> +}
> +
> +static const struct drm_connector_helper_funcs vdrm_conn_helper_funcs = {
> + .get_modes = vdrm_connector_get_mode,
> +};
> +
> +/*
> + * TODO:
> + * At the time this callback is called, the parent CRTC must be connected.
> + * Since this callback will not be called when detect() callback of the
> + * parent connector is called, vDRM driver desn't support hotplug.
> + * In the future, it is necessary that hotplug is supported.
> + */
> +static enum drm_connector_status
> +vdrm_connector_detect(struct drm_connector *connector, bool force)
> +{
> + struct vdrm_display *disp = to_vdrm_display(connector);
> + struct vdrm_device *vdrm = to_vdrm_device(connector->dev);
> + struct drm_connector *conn;
> + struct drm_connector_list_iter conn_iter;
> +
> + drm_connector_list_iter_begin(vdrm->parent, &conn_iter);
> + drm_for_each_connector_iter(conn, &conn_iter) {
> + if (!conn->state)
> + continue;
> +
> + if (conn->state->crtc == disp->parent_crtc) {
> + drm_connector_list_iter_end(&conn_iter);
> + return connector_status_connected;
> + }
> + }
> + drm_connector_list_iter_end(&conn_iter);
> + return connector_status_disconnected;
> +}
> +
> +static const struct drm_connector_funcs vdrm_conn_funcs = {
> + .reset = drm_atomic_helper_connector_reset,
> + .detect = vdrm_connector_detect,
> + .fill_modes = drm_helper_probe_single_connector_modes,
> + .destroy = drm_connector_cleanup,
> + .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
> +};
> +
> +static void vdrm_drv_finish_page_flip_internal(struct vdrm_display *disp)
> +{
> + struct drm_device *dev = &disp->dev->ddev;
> + struct drm_pending_vblank_event *event;
> + unsigned long flags;
> +
> + spin_lock_irqsave(&dev->event_lock, flags);
> + event = disp->event;
> + disp->event = NULL;
> + spin_unlock_irqrestore(&dev->event_lock, flags);
> +
> + if (event == NULL)
> + return;
> +
> + spin_lock_irqsave(&dev->event_lock, flags);
> + drm_crtc_send_vblank_event(&disp->crtc, event);
> + spin_unlock_irqrestore(&dev->event_lock, flags);
> +
> + if (disp->vblank_count) {
> + drm_crtc_vblank_put(&disp->crtc);
> + disp->vblank_count--;
> + }
> +}
> +
> +static void vdrm_plane_update(struct drm_plane *plane,
> + struct drm_atomic_state *state)
> +{
> + struct drm_plane_state *old_state = drm_atomic_get_old_plane_state(state, plane);
> + struct drm_plane_state *new_state = drm_atomic_get_new_plane_state(state, plane);
> + struct drm_crtc *vcrtc_old_state = old_state->crtc;
> + struct drm_crtc *vcrtc_plane_state = new_state->crtc;
> + struct drm_crtc *crtc;
> + struct vdrm_display *vdisplay;
> +
> + crtc = (old_state->crtc ? old_state->crtc : new_state->crtc);
> + if (WARN_ON(!crtc))
> + return;
> +
> + vdisplay = crtc_to_vdrm_display(crtc);
> +
> + old_state->crtc = vdisplay->parent_crtc;
> + new_state->crtc = vdisplay->parent_crtc;
> +
> + new_state->dst.x1 += vdisplay->plane_info.x;
> + new_state->dst.y1 += vdisplay->plane_info.y;
> + vdisplay->parent_plane_helper_funcs->atomic_update(plane, state);
> +
> + old_state->crtc = vcrtc_old_state;
> + new_state->crtc = vcrtc_plane_state;
> +}
> +
> +static struct vdrm_display *
> +vdrm_plane_find_display(struct vdrm_device *vdrm, struct drm_plane *plane)
> +{
> + struct vdrm_display *disp;
> +
> + list_for_each_entry(disp, &vdrm->disps, head) {
> + if (disp->plane == plane)
> + return disp;
> + }
> +
> + return NULL;
> +}
> +
> +static void vdrm_plane_reset(struct drm_plane *plane)
> +{
> + struct vdrm_device *vdrm = to_vdrm_device(plane->dev);
> + struct vdrm_display *disp;
> +
> + disp = vdrm_plane_find_display(vdrm, plane);
> + if (WARN_ON(!disp))
> + return;
> +
> + disp->parent_plane_funcs->reset(plane);
> + plane->state->zpos = disp->plane_info.z;
> +}
> +
> +static struct drm_property *
> +vdrm_find_parent_property(struct vdrm_device *vdrm, struct drm_property *prop)
> +{
> + int i;
> +
> + for (i = 0; i < vdrm->num_props; i++) {
> + if (vdrm->props[i].prop == prop)
> + return vdrm->props[i].parent_prop;
> + }
> +
> + return NULL;
> +}
> +
> +static int vdrm_plane_set_property(struct drm_plane *plane,
> + struct drm_plane_state *state,
> + struct drm_property *property,
> + uint64_t val)
> +{
> + struct vdrm_device *vdrm = to_vdrm_device(plane->dev);
> + struct vdrm_display *disp;
> + struct drm_property *parent_prop;
> +
> + disp = vdrm_plane_find_display(vdrm, plane);
> + if (WARN_ON(!disp))
> + return -EINVAL;
> +
> + parent_prop = vdrm_find_parent_property(vdrm, property);
> + if (parent_prop && disp->parent_plane_funcs->atomic_set_property)
> + return disp->parent_plane_funcs->atomic_set_property(plane,
> + state,
> + parent_prop,
> + val);
> +
> + if (vdrm->plane_props.offset_x == property) {
> + if (val > disp->parent_crtc->mode.hdisplay)
> + return -EINVAL;
> + disp->plane_info.x = val;
> + } else if (vdrm->plane_props.offset_y == property) {
> + if (val > disp->parent_crtc->mode.vdisplay)
> + return -EINVAL;
> + disp->plane_info.y = val;
> + } else if (vdrm->plane_props.width == property) {
> + if (val > disp->parent_crtc->mode.hdisplay)
> + return -EINVAL;
> + disp->plane_info.width = val;
> + } else if (vdrm->plane_props.height == property) {
> + if (val > disp->parent_crtc->mode.vdisplay)
> + return -EINVAL;
> + disp->plane_info.height = val;
> + } else {
> + return -EINVAL;
> + }
> +
> + return 0;
> +}
> +
> +static int vdrm_plane_get_property(struct drm_plane *plane,
> + const struct drm_plane_state *state,
> + struct drm_property *property,
> + uint64_t *val)
> +{
> + struct vdrm_device *vdrm = to_vdrm_device(plane->dev);
> + struct vdrm_display *disp;
> + struct drm_property *parent_prop;
> +
> + disp = vdrm_plane_find_display(vdrm, plane);
> + if (WARN_ON(!disp))
> + return -EINVAL;
> +
> + parent_prop = vdrm_find_parent_property(vdrm, property);
> + if (parent_prop && disp->parent_plane_funcs->atomic_get_property)
> + return disp->parent_plane_funcs->atomic_get_property(plane,
> + state,
> + parent_prop,
> + val);
> +
> + if (vdrm->plane_props.offset_x == property)
> + *val = disp->plane_info.x;
> + else if (vdrm->plane_props.offset_y == property)
> + *val = disp->plane_info.y;
> + else if (vdrm->plane_props.width == property)
> + *val = disp->plane_info.width;
> + else if (vdrm->plane_props.height == property)
> + *val = disp->plane_info.height;
> + else
> + return -EINVAL;
> +
> + return 0;
> +}
> +
> +static int vdrm_crtc_check(struct drm_crtc *crtc,
> + struct drm_atomic_state *state)
> +{
> + struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state,
> + crtc);
> + bool has_primary = crtc_state->plane_mask &
> + drm_plane_mask(crtc->primary);
> +
> + /* We always want to have an active plane with an active CRTC */
> + if (has_primary != crtc_state->enable)
> + return -EINVAL;
> +
> + return drm_atomic_add_affected_planes(state, crtc);
> +}
> +
> +static void vdrm_crtc_flush(struct drm_crtc *crtc,
> + struct drm_atomic_state *state)
> +{
> + struct vdrm_display *disp = crtc_to_vdrm_display(crtc);
> + struct vdrm_device *vdrm = disp->dev;
> +
> + if (crtc->state->event) {
> + struct drm_device *dev = crtc->dev;
> + unsigned long flags;
> +
> + if (disp->crtc_enabled) {
> + WARN_ON(drm_crtc_vblank_get(crtc) != 0);
> + disp->vblank_count++;
> + }
> +
> + spin_lock_irqsave(&dev->event_lock, flags);
> + disp->event = crtc->state->event;
> + crtc->state->event = NULL;
> + spin_unlock_irqrestore(&dev->event_lock, flags);
> + }
> +
> + if (vdrm->funcs->crtc_flush)
> + vdrm->funcs->crtc_flush(disp->parent_crtc);
> +}
> +
> +static void vdrm_crtc_enable(struct drm_crtc *crtc,
> + struct drm_atomic_state *state)
> +{
> + struct vdrm_display *disp = crtc_to_vdrm_display(crtc);
> +
> + drm_crtc_vblank_on(crtc);
> + disp->crtc_enabled = true;
> +}
> +
> +static void vdrm_crtc_disable(struct drm_crtc *crtc,
> + struct drm_atomic_state *state)
> +{
> + struct vdrm_display *disp = crtc_to_vdrm_display(crtc);
> + unsigned long flags;
> + bool pending;
> +
> + disp->crtc_enabled = false;
> + drm_crtc_vblank_off(crtc);
> +
> + spin_lock_irqsave(&crtc->dev->event_lock, flags);
> + pending = disp->event != NULL;
> + spin_unlock_irqrestore(&crtc->dev->event_lock, flags);
> +
> + if (!wait_event_timeout(disp->flip_wait, !pending,
> + msecs_to_jiffies(50))) {
> + DRM_WARN("VDRM: page flip timeout\n");
> + vdrm_drv_finish_page_flip_internal(disp);
> + }
> +
> + spin_lock_irq(&crtc->dev->event_lock);
> + if (crtc->state->event) {
> + drm_crtc_send_vblank_event(crtc, crtc->state->event);
> + crtc->state->event = NULL;
> + }
> + spin_unlock_irq(&crtc->dev->event_lock);
> +}
> +
> +static const struct drm_crtc_helper_funcs vdrm_crtc_helper_funcs = {
> + .atomic_check = vdrm_crtc_check,
> + .atomic_flush = vdrm_crtc_flush,
> + .atomic_enable = vdrm_crtc_enable,
> + .atomic_disable = vdrm_crtc_disable,
> +};
> +
> +static int vdrm_crtc_enable_vblank(struct drm_crtc *crtc)
> +{
> + struct vdrm_display *disp;
> +
> + disp = crtc_to_vdrm_display(crtc);
> + disp->vblank_enabled = true;
> +
> + return 0;
> +}
> +
> +static void vdrm_crtc_disable_vblank(struct drm_crtc *crtc)
> +{
> + struct vdrm_display *disp;
> +
> + disp = crtc_to_vdrm_display(crtc);
> + disp->vblank_enabled = false;
> +}
> +
> +static const struct drm_crtc_funcs vdrm_crtc_funcs = {
> + .reset = drm_atomic_helper_crtc_reset,
> + .destroy = drm_crtc_cleanup,
> + .set_config = drm_atomic_helper_set_config,
> + .page_flip = drm_atomic_helper_page_flip,
> + .atomic_duplicate_state = drm_atomic_helper_crtc_duplicate_state,
> + .atomic_destroy_state = drm_atomic_helper_crtc_destroy_state,
> + .enable_vblank = vdrm_crtc_enable_vblank,
> + .disable_vblank = vdrm_crtc_disable_vblank,
> +};
> +static const struct drm_encoder_funcs vdrm_encoder_funcs = {
> + .destroy = drm_encoder_cleanup,
> +};
> +
> +static int vdrm_properties_init(struct vdrm_device *vdrm, int num_props,
> + struct vdrm_property_info *props)
> +{
> + int i;
> + unsigned int w = vdrm->ddev.mode_config.max_width;
> + unsigned int h = vdrm->ddev.mode_config.max_height;
> +
> + vdrm->plane_props.offset_x =
> + drm_property_create_range(&vdrm->ddev, 0, "vdrm_offset_x", 0, w);
> + if (!vdrm->plane_props.offset_x)
> + return -1;
> + vdrm->plane_props.offset_y =
> + drm_property_create_range(&vdrm->ddev, 0, "vdrm_offset_y", 0, h);
> + if (!vdrm->plane_props.offset_y)
> + return -1;
> + vdrm->plane_props.width =
> + drm_property_create_range(&vdrm->ddev, 0, "vdrm_width", 1, w);
> + if (!vdrm->plane_props.width)
> + return -1;
> + vdrm->plane_props.height =
> + drm_property_create_range(&vdrm->ddev, 0, "vdrm_height", 1, h);
> + if (!vdrm->plane_props.height)
> + return -1;
> +
> + if (num_props == 0)
> + return 0;
> +
> + vdrm->props = devm_kzalloc(vdrm->parent->dev,
> + sizeof(*vdrm->props) * num_props,
> + GFP_KERNEL);
> + if (!vdrm->props)
> + return -ENOMEM;
> +
> + for (i = 0; i < num_props; i++) {
> + struct drm_property *p = props[i].prop;
> +
> + vdrm->props[i].prop =
> + drm_property_create_range(&vdrm->ddev, p->flags,
> + p->name, p->values[0],
> + p->values[1]);
> + if (!vdrm->props[i].prop)
> + goto err;
> +
> + vdrm->props[i].parent_prop = p;
> + vdrm->props[i].default_val = props[i].default_val;
> + }
> + vdrm->num_props = num_props;
> +
> + return 0;
> +
> +err:
> + for (i--; i >= 0; i--)
> + drm_property_destroy(&vdrm->ddev, vdrm->props[i].prop);
> + devm_kfree(vdrm->parent->dev, vdrm->props);
> + return -1;
> +}
> +
> +static int vdrm_of_get_plane(struct device_node *np,
> + int *x, int *y, int *width, int *height, int *z)
> +{
> + struct device_node *child;
> + int ret;
> +
> + child = of_get_next_child(np, NULL);
> + if (!child)
> + return -ENODEV;
> +
> + ret = of_property_read_u32(child, "x", x);
> + ret |= of_property_read_u32(child, "y", y);
> + ret |= of_property_read_u32(child, "width", width);
> + ret |= of_property_read_u32(child, "height", height);
> + ret |= of_property_read_u32(child, "zpos", z);
> +
> + of_node_put(child);
> + return ret;
> +}
> +
> +static void vdrm_dump(struct vdrm_device *vdrm)
> +{
> + struct vdrm_display *disp;
> +
> + DRM_INFO("Virtual DRM Info:\n");
> + list_for_each_entry(disp, &vdrm->disps, head) {
> + DRM_INFO("\tCONNECTOR: %d\n",
> + disp->connector.base.id);
> + DRM_INFO("\tCRTC: %d\n",
> + disp->crtc.base.id);
> + DRM_INFO("\tENCODER: %d\n",
> + disp->encoder.base.id);
> + DRM_INFO("\tPLANE: %d\n",
> + disp->plane->base.id);
> + DRM_INFO("\tParent CRTC: %d\n",
> + disp->parent_crtc->base.id);
> + }
> +}
> +
> +/**
> + * vdrm_drv_handle_vblank - handle a vblank event for vDRM
> + * @vdisplay: vDRM display object
> + */
> +void vdrm_drv_handle_vblank(struct vdrm_display *vdisplay)
> +{
> + if (vdisplay->vblank_enabled)
> + drm_crtc_handle_vblank(&vdisplay->crtc);
> +}
> +
> +/**
> + * vdrm_drv_finish_page_flip - handle a page flip event for vDRM
> + * @vdisplay: vDRM display object
> + */
> +void vdrm_drv_finish_page_flip(struct vdrm_display *vdisplay)
> +{
> + vdrm_drv_finish_page_flip_internal(vdisplay);
> +}
> +
> +DEFINE_DRM_GEM_CMA_FOPS(vdrm_fops);
> +
> +static struct drm_driver vdrm_driver = {
> + .driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC,
> + .dumb_create = vdrm_dumb_create,
> + .fops = &vdrm_fops,
> + .name = "virt-drm",
> + .desc = "Virtual DRM driver",
> + .date = "20201104",
> + .major = 1,
> + .minor = 0,
> +};
> +
> +/**
> + * vdrm_drv_init - Initialize vDRM device
> + * @dev: parent DRM device
> + * @np: vDRM device node in DTB
> + * @num_props: number of parent property objects
> + * @props: parent plane properties used in vDRM
> + * @funcs: callbacks for vDRM
> + *
> + * Allocates a new vDRM device, initializes mode_config of the vDRM device
> + * and allocates property objects. Not initialize plane, crtc, encoder and
> + * connector. Initialization of plane must be done in vdrm_drv_plane_init()
> + * and initialization of crtc, encoder and connector must be done by
> + * vdrm_drv_display_init(). Also, after initializing the plane, crtc,
> + * connector, and encoder, register vDRM device must be done by
> + * vdrm_drv_register().
> + *
> + * Returns:
> + * vDRM object (&vdrm_device) on success, error code encoded into the pointer
> + * on failure.
> + */
> +struct vdrm_device *vdrm_drv_init(struct drm_device *dev,
> + struct device_node *np, int num_props,
> + struct vdrm_property_info *props,
> + const struct vdrm_funcs *funcs)
> +{
> + struct vdrm_device *vdrm;
> + struct vdrm_plane_info plane_info;
> + int ret;
> +
> + if (!of_device_is_compatible(np, "virt-drm"))
> + return ERR_PTR(-ENODEV);
> +
> + /* get plane information from device tree */
> + ret = vdrm_of_get_plane(np, &plane_info.x, &plane_info.y,
> + &plane_info.width, &plane_info.height,
> + &plane_info.z);
> + if (ret < 0) {
> + DRM_WARN("VDRM: failed get plane node of %s\n",
> + of_node_full_name(np));
> + return ERR_PTR(ret);
> + }
> +
> + vdrm_driver.prime_handle_to_fd = dev->driver->prime_handle_to_fd;
> + vdrm_driver.prime_fd_to_handle = dev->driver->prime_fd_to_handle;
> + vdrm_driver.gem_prime_import_sg_table =
> + dev->driver->gem_prime_import_sg_table;
> + vdrm_driver.gem_prime_mmap = dev->driver->gem_prime_mmap;
> +
> + vdrm = devm_drm_dev_alloc(dev->dev, &vdrm_driver, struct vdrm_device,
> + ddev);
> + if (IS_ERR(vdrm))
> + return vdrm;
> +
> + vdrm->parent = dev;
> + vdrm->funcs = funcs;
> + vdrm->of_plane_info = plane_info;
> +
> + INIT_LIST_HEAD(&vdrm->disps);
> +
> + ret = drmm_mode_config_init(&vdrm->ddev);
> + if (ret)
> + goto failed;
> +
> + vdrm->ddev.mode_config.min_width = 0;
> + vdrm->ddev.mode_config.min_height = 0;
> + vdrm->ddev.mode_config.max_width = 8190;
> + vdrm->ddev.mode_config.max_height = 8190;
> + vdrm->ddev.mode_config.normalize_zpos = true;
> + vdrm->ddev.mode_config.funcs = &vdrm_mode_config_funcs;
> +
> + ret = vdrm_properties_init(vdrm, num_props, props);
> + if (ret < 0)
> + goto failed;
> +
> + drm_dev_set_unique(&vdrm->ddev, of_node_full_name(np));
> + return vdrm;
> +
> +failed:
> + kfree(vdrm);
> + return ERR_PTR(ret);
> +}
> +
> +/**
> + * vdrm_drv_plane_init - Initialize the plane used by vDRM
> + * @vdrm: vDRM object
> + * @plane: plane to assign to vDRM
> + * @funcs: callbacks for the plane
> + * @helper_funcs: helper vtable to set for plane
> + * @formats: color formats
> + * @num_formats: number of color formats
> + * @max_zpos: max value for zpos property of plane
> + *
> + * Initializes a plane object of PRIMARY type by drm_universal_plane_init()
> + * and initializes @plane's properties. The property passed by vdrm_drv_init()
> + * is set to @plane.
> + *
> + * Returns:
> + * Zero on success, error code on failure.
> + */
> +int vdrm_drv_plane_init(struct vdrm_device *vdrm, struct drm_plane *plane,
> + const struct drm_plane_funcs *funcs,
> + const struct drm_plane_helper_funcs *helper_funcs,
> + const u32 *formats, unsigned int num_formats,
> + int max_zpos)
> +{
> + struct vdrm_display *disp;
> + int i, ret;
> +
> + disp = kzalloc(sizeof(*disp), GFP_KERNEL);
> + if (!disp)
> + return -ENOMEM;
> +
> + disp->dev = vdrm;
> + disp->plane = plane;
> + disp->plane_info = vdrm->of_plane_info;
> +
> + disp->parent_plane_funcs = funcs;
> + disp->parent_plane_helper_funcs = helper_funcs;
> + disp->plane_funcs = *funcs;
> + disp->plane_helper_funcs = *helper_funcs;
> +
> + disp->plane_funcs.reset = vdrm_plane_reset;
> + disp->plane_funcs.atomic_set_property = vdrm_plane_set_property;
> + disp->plane_funcs.atomic_get_property = vdrm_plane_get_property;
> + disp->plane_helper_funcs.atomic_update = vdrm_plane_update;
> +
> + drm_plane_helper_add(disp->plane, &disp->plane_helper_funcs);
> + ret = drm_universal_plane_init(&vdrm->ddev, plane, 0,
> + &disp->plane_funcs, formats,
> + num_formats, NULL,
> + DRM_PLANE_TYPE_PRIMARY, NULL);
> + if (ret) {
> + kfree(disp);
> + return ret;
> + }
> +
> + drm_plane_create_alpha_property(plane);
> + drm_plane_create_zpos_property(plane, disp->plane_info.z, 0, max_zpos);
> + drm_object_attach_property(&plane->base,
> + vdrm->plane_props.offset_x,
> + disp->plane_info.x);
> + drm_object_attach_property(&plane->base,
> + vdrm->plane_props.offset_y,
> + disp->plane_info.y);
> + drm_object_attach_property(&plane->base,
> + vdrm->plane_props.width,
> + disp->plane_info.width);
> + drm_object_attach_property(&plane->base,
> + vdrm->plane_props.height,
> + disp->plane_info.height);
> + for (i = 0; i < vdrm->num_props; i++) {
> + drm_object_attach_property(&plane->base,
> + vdrm->props[i].prop,
> + vdrm->props[i].default_val);
> + }
> +
> + INIT_LIST_HEAD(&disp->head);
> + list_add_tail(&disp->head, &vdrm->disps);
> + vdrm->num_crtcs++;
> + return 0;
> +}
> +
> +/**
> + * vdrm_drv_display_init - Initialize the vDRM display object
> + * @vdrm: vDRM object
> + * @crtc: parent crtc to be linked with the vDRM crtc
> + * @plane: plane assigned to vDRM
> + *
> + * Initializes crtc, connector and encorder, and links @crtc to crtc of vDRM.
> + *
> + * Returns:
> + * vDRM display object on success, error code encoded into the pointer on
> + * failure.
> + */
> +struct vdrm_display *vdrm_drv_display_init(struct vdrm_device *vdrm,
> + struct drm_crtc *crtc,
> + struct drm_plane *plane)
> +{
> + struct vdrm_display *disp;
> + int ret;
> +
> + disp = vdrm_plane_find_display(vdrm, plane);
> + if (!disp)
> + return ERR_PTR(-EINVAL);
> +
> + drm_crtc_helper_add(&disp->crtc, &vdrm_crtc_helper_funcs);
> + ret = drm_crtc_init_with_planes(&vdrm->ddev, &disp->crtc, plane, NULL,
> + &vdrm_crtc_funcs, NULL);
> + if (ret)
> + return ERR_PTR(ret);
> +
> + drm_connector_helper_add(&disp->connector, &vdrm_conn_helper_funcs);
> + ret = drm_connector_init(&vdrm->ddev, &disp->connector,
> + &vdrm_conn_funcs, DRM_MODE_CONNECTOR_VIRTUAL);
> + if (ret)
> + return ERR_PTR(ret);
> +
> + disp->encoder.possible_crtcs = drm_crtc_mask(&disp->crtc);
> + ret = drm_encoder_init(&vdrm->ddev, &disp->encoder, &vdrm_encoder_funcs,
> + DRM_MODE_ENCODER_NONE, NULL);
> + if (ret)
> + return ERR_PTR(ret);
> +
> + ret = drm_connector_attach_encoder(&disp->connector, &disp->encoder);
> + if (ret)
> + return ERR_PTR(ret);
> +
> + init_waitqueue_head(&disp->flip_wait);
> + disp->parent_crtc = crtc;
> +
> + return disp;
> +}
> +
> +/**
> + * vdrm_drv_register - Register vDRM device
> + * @vdrm: vDRM object
> + *
> + * Returns:
> + * Zero on success, error code on failure.
> + */
> +int vdrm_drv_register(struct vdrm_device *vdrm)
> +{
> + int ret;
> + struct drm_device *dev = &vdrm->ddev;
> +
> + ret = drm_vblank_init(dev, vdrm->num_crtcs);
> + if (ret)
> + return ret;
> +
> + drm_mode_config_reset(dev);
> +
> + ret = drm_dev_register(dev, 0);
> + if (ret)
> + return ret;
> +
> + dev->irq_enabled = true;
> +
> + DRM_INFO("Virtual Device is initialized.\n");
> +
> + vdrm_dump(vdrm);
> +
> + return 0;
> +}
> +
> +/**
> + * vdrm_drv_fini - release vDRM resources
> + * @vdrm: vDRM object
> + */
> +void vdrm_drv_fini(struct vdrm_device *vdrm)
> +{
> + struct vdrm_display *disp;
> +
> + if (vdrm->ddev.registered)
> + drm_dev_unregister(&vdrm->ddev);
> + drm_mode_config_cleanup(&vdrm->ddev);
> +
> + list_for_each_entry(disp, &vdrm->disps, head)
> + kfree(disp);
> +}
> diff --git a/drivers/gpu/drm/vdrm/vdrm_drv.h b/drivers/gpu/drm/vdrm/vdrm_drv.h
> new file mode 100644
> index 000000000000..67b8e02efddf
> --- /dev/null
> +++ b/drivers/gpu/drm/vdrm/vdrm_drv.h
> @@ -0,0 +1,80 @@
> +/* SPDX-License-Identifier: GPL-2.0+ */
> +/*
> + * vdrm_drv.h -- Virtual DRM driver
> + *
> + * Copyright (C) 2021 Renesas Electronics Corporation
> + */
> +
> +#ifndef __VDRM_DRV_H__
> +#define __VDRM_DRV_H__
> +
> +#include <drm/drm_device.h>
> +
> +#include "vdrm_api.h"
> +
> +struct vdrm_property {
> + struct drm_property *prop;
> + struct drm_property *parent_prop;
> + uint64_t default_val;
> +};
> +
> +struct vdrm_plane_info {
> + int x;
> + int y;
> + unsigned int width;
> + unsigned int height;
> + unsigned int z;
> +};
> +
> +struct vdrm_device;
> +
> +struct vdrm_display {
> + struct drm_connector connector;
> + struct drm_crtc crtc;
> + struct drm_crtc *parent_crtc;
> + struct drm_plane *plane;
> + struct drm_encoder encoder;
> + struct drm_pending_vblank_event *event;
> + struct vdrm_device *dev;
> + bool vblank_enabled;
> + wait_queue_head_t flip_wait;
> + bool crtc_enabled;
> + int vblank_count;
> +
> + struct list_head head;
> +
> + struct vdrm_plane_info plane_info;
> +
> + const struct drm_plane_funcs *parent_plane_funcs;
> + const struct drm_plane_helper_funcs *parent_plane_helper_funcs;
> + struct drm_plane_funcs plane_funcs;
> + struct drm_plane_helper_funcs plane_helper_funcs;
> +};
> +
> +struct vdrm_device {
> + struct drm_device ddev;
> + struct drm_device *parent;
> +
> + int num_crtcs;
> + struct list_head disps;
> +
> + const struct vdrm_funcs *funcs;
> + struct vdrm_property *props;
> + int num_props;
> +
> + struct {
> + struct drm_property *offset_x;
> + struct drm_property *offset_y;
> + struct drm_property *width;
> + struct drm_property *height;
> + } plane_props;
> +
> + struct vdrm_plane_info of_plane_info;
> +};
> +
> +static inline struct vdrm_device *to_vdrm_device(struct drm_device *dev)
> +{
> + return container_of(dev, struct vdrm_device, ddev);
> +}
> +
> +#endif /* __VDRM_DRV_H__ */
> --
> 2.25.1
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