Quelle  vkms_writeback.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0+

#include <linux/iosys-map.h>

#include <drm/drm_atomic.h>
#include <drm/drm_edid.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_writeback.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_atomic_helper.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_gem_shmem_helper.h>

#include "vkms_drv.h"
#include "vkms_formats.h"

static const u32 vkms_wb_formats[] = {
 DRM_FORMAT_ARGB8888,
 DRM_FORMAT_XRGB8888,
 DRM_FORMAT_ABGR8888,
 DRM_FORMAT_XRGB16161616,
 DRM_FORMAT_ARGB16161616,
 DRM_FORMAT_RGB565
};

static const struct drm_connector_funcs vkms_wb_connector_funcs = {
 .fill_modes = drm_helper_probe_single_connector_modes,
 .reset = drm_atomic_helper_connector_reset,
 .atomic_duplicate_state = drm_atomic_helper_connector_duplicate_state,
 .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
};

static int vkms_wb_atomic_check(struct drm_connector *connector,
    struct drm_atomic_state *state)
{
 struct drm_connector_state *conn_state =
  drm_atomic_get_new_connector_state(state, connector);
 struct drm_crtc_state *crtc_state;
 struct drm_framebuffer *fb;
 const struct drm_display_mode *mode;
 int ret;

 if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
  return 0;

 if (!conn_state->crtc)
  return 0;

 crtc_state = drm_atomic_get_new_crtc_state(state, conn_state->crtc);
 mode = &crtc_state->mode;

 fb = conn_state->writeback_job->fb;
 if (fb->width != mode->hdisplay || fb->height != mode->vdisplay) {
  DRM_DEBUG_KMS("Invalid framebuffer size %ux%u\n",
         fb->width, fb->height);
  return -EINVAL;
 }

 ret = drm_atomic_helper_check_wb_connector_state(connector, state);
 if (ret < 0)
  return ret;

 return 0;
}

static int vkms_wb_connector_get_modes(struct drm_connector *connector)
{
 struct drm_device *dev = connector->dev;

 return drm_add_modes_noedid(connector, dev->mode_config.max_width,
        dev->mode_config.max_height);
}

static int vkms_wb_prepare_job(struct drm_writeback_connector *wb_connector,
          struct drm_writeback_job *job)
{
 struct vkms_writeback_job *vkmsjob;
 int ret;

 if (!job->fb)
  return 0;

 vkmsjob = kzalloc(sizeof(*vkmsjob), GFP_KERNEL);
 if (!vkmsjob)
  return -ENOMEM;

 ret = drm_gem_fb_vmap(job->fb, vkmsjob->wb_frame_info.map, vkmsjob->data);
 if (ret) {
  DRM_ERROR("vmap failed: %d\n", ret);
  goto err_kfree;
 }

 vkmsjob->wb_frame_info.fb = job->fb;
 drm_framebuffer_get(vkmsjob->wb_frame_info.fb);

 job->priv = vkmsjob;

 return 0;

err_kfree:
 kfree(vkmsjob);
 return ret;
}

static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector,
    struct drm_writeback_job *job)
{
 struct vkms_writeback_job *vkmsjob = job->priv;
 struct vkms_output *vkms_output = container_of(connector,
             struct vkms_output,
             wb_connector);

 if (!job->fb)
  return;

 drm_gem_fb_vunmap(job->fb, vkmsjob->wb_frame_info.map);

 drm_framebuffer_put(vkmsjob->wb_frame_info.fb);

 vkms_set_composer(vkms_output, false);
 kfree(vkmsjob);
}

static void vkms_wb_atomic_commit(struct drm_connector *conn,
      struct drm_atomic_state *state)
{
 struct drm_connector_state *connector_state = drm_atomic_get_new_connector_state(state,
            conn);
 struct vkms_output *output = drm_crtc_to_vkms_output(connector_state->crtc);
 struct drm_writeback_connector *wb_conn = &output->wb_connector;
 struct drm_connector_state *conn_state = wb_conn->base.state;
 struct vkms_crtc_state *crtc_state = output->composer_state;
 struct drm_framebuffer *fb = connector_state->writeback_job->fb;
 u16 crtc_height = crtc_state->base.mode.vdisplay;
 u16 crtc_width = crtc_state->base.mode.hdisplay;
 struct vkms_writeback_job *active_wb;
 struct vkms_frame_info *wb_frame_info;
 u32 wb_format = fb->format->format;

 if (!conn_state)
  return;

 vkms_set_composer(output, true);

 active_wb = conn_state->writeback_job->priv;
 wb_frame_info = &active_wb->wb_frame_info;

 spin_lock_irq(&output->composer_lock);
 crtc_state->active_writeback = active_wb;
 crtc_state->wb_pending = true;
 spin_unlock_irq(&output->composer_lock);
 drm_writeback_queue_job(wb_conn, connector_state);
 active_wb->pixel_write = get_pixel_write_function(wb_format);
 drm_rect_init(&wb_frame_info->src, 0, 0, crtc_width, crtc_height);
 drm_rect_init(&wb_frame_info->dst, 0, 0, crtc_width, crtc_height);
}

static const struct drm_connector_helper_funcs vkms_wb_conn_helper_funcs = {
 .get_modes = vkms_wb_connector_get_modes,
 .prepare_writeback_job = vkms_wb_prepare_job,
 .cleanup_writeback_job = vkms_wb_cleanup_job,
 .atomic_commit = vkms_wb_atomic_commit,
 .atomic_check = vkms_wb_atomic_check,
};

int vkms_enable_writeback_connector(struct vkms_device *vkmsdev,
        struct vkms_output *vkms_output)
{
 struct drm_writeback_connector *wb = &vkms_output->wb_connector;
 int ret;

 ret = drmm_encoder_init(&vkmsdev->drm, &vkms_output->wb_encoder,
    NULL, DRM_MODE_ENCODER_VIRTUAL, NULL);
 if (ret)
  return ret;
 vkms_output->wb_encoder.possible_crtcs |= drm_crtc_mask(&vkms_output->crtc);

 drm_connector_helper_add(&wb->base, &vkms_wb_conn_helper_funcs);

 return drmm_writeback_connector_init(&vkmsdev->drm, wb,
          &vkms_wb_connector_funcs,
          &vkms_output->wb_encoder,
          vkms_wb_formats,
          ARRAY_SIZE(vkms_wb_formats));
}