Quelle  rcar_du_writeback.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0
/*
 * R-Car Display Unit Writeback Support
 *
 * Copyright (C) 2019 Laurent Pinchart <laurent.pinchart@ideasonboard.com>
 */

#include <drm/drm_atomic_helper.h>
#include <drm/drm_device.h>
#include <drm/drm_edid.h>
#include <drm/drm_fourcc.h>
#include <drm/drm_framebuffer.h>
#include <drm/drm_probe_helper.h>
#include <drm/drm_writeback.h>

#include "rcar_du_crtc.h"
#include "rcar_du_drv.h"
#include "rcar_du_kms.h"
#include "rcar_du_writeback.h"

/**
 * struct rcar_du_wb_conn_state - Driver-specific writeback connector state
 * @state: base DRM connector state
 * @format: format of the writeback framebuffer
 */
struct rcar_du_wb_conn_state {
 struct drm_connector_state state;
 const struct rcar_du_format_info *format;
};

#define to_rcar_wb_conn_state(s) \
 container_of(s, struct rcar_du_wb_conn_state, state)

/**
 * struct rcar_du_wb_job - Driver-private data for writeback jobs
 * @sg_tables: scatter-gather tables for the framebuffer memory
 */
struct rcar_du_wb_job {
 struct sg_table sg_tables[3];
};

static int rcar_du_wb_conn_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 rcar_du_wb_prepare_job(struct drm_writeback_connector *connector,
      struct drm_writeback_job *job)
{
 struct rcar_du_crtc *rcrtc = wb_to_rcar_crtc(connector);
 struct rcar_du_wb_job *rjob;
 int ret;

 if (!job->fb)
  return 0;

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

 /* Map the framebuffer to the VSP. */
 ret = rcar_du_vsp_map_fb(rcrtc->vsp, job->fb, rjob->sg_tables);
 if (ret < 0) {
  kfree(rjob);
  return ret;
 }

 job->priv = rjob;
 return 0;
}

static void rcar_du_wb_cleanup_job(struct drm_writeback_connector *connector,
       struct drm_writeback_job *job)
{
 struct rcar_du_crtc *rcrtc = wb_to_rcar_crtc(connector);
 struct rcar_du_wb_job *rjob = job->priv;

 if (!job->fb)
  return;

 rcar_du_vsp_unmap_fb(rcrtc->vsp, job->fb, rjob->sg_tables);
 kfree(rjob);
}

static const struct drm_connector_helper_funcs rcar_du_wb_conn_helper_funcs = {
 .get_modes = rcar_du_wb_conn_get_modes,
 .prepare_writeback_job = rcar_du_wb_prepare_job,
 .cleanup_writeback_job = rcar_du_wb_cleanup_job,
};

static struct drm_connector_state *
rcar_du_wb_conn_duplicate_state(struct drm_connector *connector)
{
 struct rcar_du_wb_conn_state *copy;

 if (WARN_ON(!connector->state))
  return NULL;

 copy = kzalloc(sizeof(*copy), GFP_KERNEL);
 if (!copy)
  return NULL;

 __drm_atomic_helper_connector_duplicate_state(connector, ©->state);

 return ©->state;
}

static void rcar_du_wb_conn_destroy_state(struct drm_connector *connector,
       struct drm_connector_state *state)
{
 __drm_atomic_helper_connector_destroy_state(state);
 kfree(to_rcar_wb_conn_state(state));
}

static void rcar_du_wb_conn_reset(struct drm_connector *connector)
{
 struct rcar_du_wb_conn_state *state;

 if (connector->state) {
  rcar_du_wb_conn_destroy_state(connector, connector->state);
  connector->state = NULL;
 }

 state = kzalloc(sizeof(*state), GFP_KERNEL);
 if (state == NULL)
  return;

 __drm_atomic_helper_connector_reset(connector, &state->state);
}

static const struct drm_connector_funcs rcar_du_wb_conn_funcs = {
 .reset = rcar_du_wb_conn_reset,
 .fill_modes = drm_helper_probe_single_connector_modes,
 .destroy = drm_connector_cleanup,
 .atomic_duplicate_state = rcar_du_wb_conn_duplicate_state,
 .atomic_destroy_state = rcar_du_wb_conn_destroy_state,
};

static int rcar_du_wb_enc_atomic_check(struct drm_encoder *encoder,
           struct drm_crtc_state *crtc_state,
           struct drm_connector_state *conn_state)
{
 struct rcar_du_wb_conn_state *wb_state =
  to_rcar_wb_conn_state(conn_state);
 const struct drm_display_mode *mode = &crtc_state->mode;
 struct drm_device *dev = encoder->dev;
 struct drm_framebuffer *fb;

 if (!conn_state->writeback_job)
  return 0;

 fb = conn_state->writeback_job->fb;

 /*
 * Verify that the framebuffer format is supported and that its size
 * matches the current mode.
 */
 if (fb->width != mode->hdisplay || fb->height != mode->vdisplay) {
  dev_dbg(dev->dev, "%s: invalid framebuffer size %ux%u\n",
   __func__, fb->width, fb->height);
  return -EINVAL;
 }

 wb_state->format = rcar_du_format_info(fb->format->format);
 if (wb_state->format == NULL) {
  dev_dbg(dev->dev, "%s: unsupported format %p4cc\n", __func__,
   &fb->format->format);
  return -EINVAL;
 }

 return 0;
}

static const struct drm_encoder_helper_funcs rcar_du_wb_enc_helper_funcs = {
 .atomic_check = rcar_du_wb_enc_atomic_check,
};

/*
 * Only RGB formats are currently supported as the VSP outputs RGB to the DU
 * and can't convert to YUV separately for writeback.
 */
static const u32 writeback_formats[] = {
 DRM_FORMAT_RGB332,
 DRM_FORMAT_ARGB4444,
 DRM_FORMAT_XRGB4444,
 DRM_FORMAT_ARGB1555,
 DRM_FORMAT_XRGB1555,
 DRM_FORMAT_RGB565,
 DRM_FORMAT_BGR888,
 DRM_FORMAT_RGB888,
 DRM_FORMAT_BGRA8888,
 DRM_FORMAT_BGRX8888,
 DRM_FORMAT_ARGB8888,
 DRM_FORMAT_XRGB8888,
};

int rcar_du_writeback_init(struct rcar_du_device *rcdu,
      struct rcar_du_crtc *rcrtc)
{
 struct drm_writeback_connector *wb_conn = &rcrtc->writeback;

 drm_connector_helper_add(&wb_conn->base,
     &rcar_du_wb_conn_helper_funcs);

 return drm_writeback_connector_init(&rcdu->ddev, wb_conn,
         &rcar_du_wb_conn_funcs,
         &rcar_du_wb_enc_helper_funcs,
         writeback_formats,
         ARRAY_SIZE(writeback_formats),
         1 << drm_crtc_index(&rcrtc->crtc));
}

void rcar_du_writeback_setup(struct rcar_du_crtc *rcrtc,
        struct vsp1_du_writeback_config *cfg)
{
 struct rcar_du_wb_conn_state *wb_state;
 struct drm_connector_state *state;
 struct rcar_du_wb_job *rjob;
 struct drm_framebuffer *fb;
 unsigned int i;

 state = rcrtc->writeback.base.state;
 if (!state || !state->writeback_job)
  return;

 fb = state->writeback_job->fb;
 rjob = state->writeback_job->priv;
 wb_state = to_rcar_wb_conn_state(state);

 cfg->pixelformat = wb_state->format->v4l2;
 cfg->pitch = fb->pitches[0];

 for (i = 0; i < wb_state->format->planes; ++i)
  cfg->mem[i] = sg_dma_address(rjob->sg_tables[i].sgl)
       + fb->offsets[i];

 drm_writeback_queue_job(&rcrtc->writeback, state);
}

void rcar_du_writeback_complete(struct rcar_du_crtc *rcrtc)
{
 drm_writeback_signal_completion(&rcrtc->writeback, 0);
}