Implement writeback support for R-Car Gen3 by exposing writeback
connectors. Behind the scene the calls are forwarded to the VSP
backend.
Using writeback connectors will allow implemented writeback support for
R-Car Gen2 with a consistent API if desired.
Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@xxxxxxxxxxxxxxxx>
Reviewed-by: Kieran Bingham <kieran.bingham+renesas@xxxxxxxxxxxxxxxx>
---
Changes since v6:
- Rename rcar_du_writeback_atomic_flush() to rcar_du_writeback_setup()
Changes since v5:
- Skip writeback connector when configuring output routing
- Implement writeback connector atomic state operations
---
drivers/gpu/drm/rcar-du/Kconfig | 4 +
drivers/gpu/drm/rcar-du/Makefile | 3 +-
drivers/gpu/drm/rcar-du/rcar_du_crtc.c | 7 +-
drivers/gpu/drm/rcar-du/rcar_du_crtc.h | 7 +-
drivers/gpu/drm/rcar-du/rcar_du_kms.c | 12 +
drivers/gpu/drm/rcar-du/rcar_du_vsp.c | 5 +
drivers/gpu/drm/rcar-du/rcar_du_writeback.c | 243 ++++++++++++++++++++
drivers/gpu/drm/rcar-du/rcar_du_writeback.h | 39 ++++
8 files changed, 317 insertions(+), 3 deletions(-)
create mode 100644 drivers/gpu/drm/rcar-du/rcar_du_writeback.c
create mode 100644 drivers/gpu/drm/rcar-du/rcar_du_writeback.h
diff --git a/drivers/gpu/drm/rcar-du/Kconfig b/drivers/gpu/drm/rcar-du/Kconfig
index 7c36e2777a15..1529849e217e 100644
--- a/drivers/gpu/drm/rcar-du/Kconfig
+++ b/drivers/gpu/drm/rcar-du/Kconfig
@@ -36,3 +36,7 @@ config DRM_RCAR_VSP
depends on VIDEO_RENESAS_VSP1=y || (VIDEO_RENESAS_VSP1 && DRM_RCAR_DU=m)
help
Enable support to expose the R-Car VSP Compositor as KMS planes.
+
+config DRM_RCAR_WRITEBACK
+ bool
+ default y if ARM64
diff --git a/drivers/gpu/drm/rcar-du/Makefile b/drivers/gpu/drm/rcar-du/Makefile
index 2a3b8d7972b5..6c2ed9c46467 100644
--- a/drivers/gpu/drm/rcar-du/Makefile
+++ b/drivers/gpu/drm/rcar-du/Makefile
@@ -4,7 +4,7 @@ rcar-du-drm-y := rcar_du_crtc.o \
rcar_du_encoder.o \
rcar_du_group.o \
rcar_du_kms.o \
- rcar_du_plane.o
+ rcar_du_plane.o \
rcar-du-drm-$(CONFIG_DRM_RCAR_LVDS) += rcar_du_of.o \
rcar_du_of_lvds_r8a7790.dtb.o \
@@ -13,6 +13,7 @@ rcar-du-drm-$(CONFIG_DRM_RCAR_LVDS) += rcar_du_of.o \
rcar_du_of_lvds_r8a7795.dtb.o \
rcar_du_of_lvds_r8a7796.dtb.o
rcar-du-drm-$(CONFIG_DRM_RCAR_VSP) += rcar_du_vsp.o
+rcar-du-drm-$(CONFIG_DRM_RCAR_WRITEBACK) += rcar_du_writeback.o
obj-$(CONFIG_DRM_RCAR_DU) += rcar-du-drm.o
obj-$(CONFIG_DRM_RCAR_DW_HDMI) += rcar_dw_hdmi.o
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
index 471ce464654a..2da46e3dc4ae 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.c
@@ -647,8 +647,13 @@ static int rcar_du_crtc_atomic_check(struct drm_crtc *crtc,
rstate->outputs = 0;
drm_for_each_encoder_mask(encoder, crtc->dev, state->encoder_mask) {
- struct rcar_du_encoder *renc = to_rcar_encoder(encoder);
+ struct rcar_du_encoder *renc;
+ /* Skip the writeback encoder. */
+ if (encoder->encoder_type == DRM_MODE_ENCODER_VIRTUAL)
+ continue;
+
+ renc = to_rcar_encoder(encoder);
rstate->outputs |= BIT(renc->output);
}
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
index af9527c1d238..3b7fc668996f 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
+++ b/drivers/gpu/drm/rcar-du/rcar_du_crtc.h
@@ -15,6 +15,7 @@
#include <linux/wait.h>
#include <drm/drm_crtc.h>
+#include <drm/drm_writeback.h>
#include <media/vsp1.h>
@@ -40,6 +41,7 @@ struct rcar_du_vsp;
* @group: CRTC group this CRTC belongs to
* @vsp: VSP feeding video to this CRTC
* @vsp_pipe: index of the VSP pipeline feeding video to this CRTC
+ * @writeback: the writeback connector
*/
struct rcar_du_crtc {
struct drm_crtc crtc;
@@ -67,9 +69,12 @@ struct rcar_du_crtc {
const char *const *sources;
unsigned int sources_count;
+
+ struct drm_writeback_connector writeback;
};
-#define to_rcar_crtc(c) container_of(c, struct rcar_du_crtc, crtc)
+#define to_rcar_crtc(c) container_of(c, struct rcar_du_crtc, crtc)
+#define wb_to_rcar_crtc(c) container_of(c, struct rcar_du_crtc, writeback)
/**
* struct rcar_du_crtc_state - Driver-specific CRTC state
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_kms.c b/drivers/gpu/drm/rcar-du/rcar_du_kms.c
index 3a5e719a6b66..f8f7fff34dff 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_kms.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_kms.c
@@ -26,6 +26,7 @@
#include "rcar_du_kms.h"
#include "rcar_du_regs.h"
#include "rcar_du_vsp.h"
+#include "rcar_du_writeback.h"
/* -----------------------------------------------------------------------------
* Format helpers
@@ -664,6 +665,17 @@ int rcar_du_modeset_init(struct rcar_du_device *rcdu)
encoder->possible_clones = (1 << num_encoders) - 1;
}
+ /* Create the writeback connectors. */
+ if (rcdu->info->gen >= 3) {
+ for (i = 0; i < rcdu->num_crtcs; ++i) {
+ struct rcar_du_crtc *rcrtc = &rcdu->crtcs[i];
+
+ ret = rcar_du_writeback_init(rcdu, rcrtc);
+ if (ret < 0)
+ return ret;
+ }
+ }
+
/*
* Initialize the default DPAD0 source to the index of the first DU
* channel that can be connected to DPAD0. The exact value doesn't
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_vsp.c b/drivers/gpu/drm/rcar-du/rcar_du_vsp.c
index 7e25e9bc7829..5e4faf258c31 100644
--- a/drivers/gpu/drm/rcar-du/rcar_du_vsp.c
+++ b/drivers/gpu/drm/rcar-du/rcar_du_vsp.c
@@ -27,6 +27,7 @@
#include "rcar_du_drv.h"
#include "rcar_du_kms.h"
#include "rcar_du_vsp.h"
+#include "rcar_du_writeback.h"
static void rcar_du_vsp_complete(void *private, unsigned int status, u32 crc)
{
@@ -37,6 +38,8 @@ static void rcar_du_vsp_complete(void *private, unsigned int status, u32 crc)
if (status & VSP1_DU_STATUS_COMPLETE)
rcar_du_crtc_finish_page_flip(crtc);
+ if (status & VSP1_DU_STATUS_WRITEBACK)
+ rcar_du_writeback_complete(crtc);
drm_crtc_add_crc_entry(&crtc->crtc, false, 0, &crc);
}
@@ -108,6 +111,8 @@ void rcar_du_vsp_atomic_flush(struct rcar_du_crtc *crtc)
state = to_rcar_crtc_state(crtc->crtc.state);
cfg.crc = state->crc;
+ rcar_du_writeback_setup(crtc, &cfg.writeback);
+
vsp1_du_atomic_flush(crtc->vsp->vsp, crtc->vsp_pipe, &cfg);
}
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_writeback.c b/drivers/gpu/drm/rcar-du/rcar_du_writeback.c
new file mode 100644
index 000000000000..989a0be94131
--- /dev/null
+++ b/drivers/gpu/drm/rcar-du/rcar_du_writeback.c
@@ -0,0 +1,243 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * rcar_du_writeback.c -- R-Car Display Unit Writeback Support
+ *
+ * Copyright (C) 2019 Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
+ */
+
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_device.h>
+#include <drm/drm_fourcc.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"
+
+/**
+ * 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 || !conn_state->writeback_job->fb)
+ 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 %08x\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;
+
+ wb_conn->encoder.possible_crtcs = 1 << drm_crtc_index(&rcrtc->crtc);
+ 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));
+}
+
+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 || !state->writeback_job->fb)
+ 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);
+}
diff --git a/drivers/gpu/drm/rcar-du/rcar_du_writeback.h b/drivers/gpu/drm/rcar-du/rcar_du_writeback.h
new file mode 100644
index 000000000000..fa87ebf8d21f
--- /dev/null
+++ b/drivers/gpu/drm/rcar-du/rcar_du_writeback.h
@@ -0,0 +1,39 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * rcar_du_writeback.h -- R-Car Display Unit Writeback Support
+ *
+ * Copyright (C) 2019 Laurent Pinchart <laurent.pinchart@xxxxxxxxxxxxxxxx>
+ */
+
+#ifndef __RCAR_DU_WRITEBACK_H__
+#define __RCAR_DU_WRITEBACK_H__
+
+#include <drm/drm_plane.h>
+
+struct rcar_du_crtc;
+struct rcar_du_device;
+struct vsp1_du_atomic_pipe_config;
+
+#ifdef CONFIG_DRM_RCAR_WRITEBACK
+int rcar_du_writeback_init(struct rcar_du_device *rcdu,
+ struct rcar_du_crtc *rcrtc);
+void rcar_du_writeback_setup(struct rcar_du_crtc *rcrtc,
+ struct vsp1_du_writeback_config *cfg);
+void rcar_du_writeback_complete(struct rcar_du_crtc *rcrtc);
+#else
+static inline int rcar_du_writeback_init(struct rcar_du_device *rcdu,
+ struct rcar_du_crtc *rcrtc)
+{
+ return -ENXIO;
+}
+static inline void
+rcar_du_writeback_setup(struct rcar_du_crtc *rcrtc,
+ struct vsp1_du_writeback_config *cfg)
+{
+}
+static inline void rcar_du_writeback_complete(struct rcar_du_crtc *rcrtc)
+{
+}
+#endif
+
+#endif /* __RCAR_DU_WRITEBACK_H__ */
--
Regards,
Laurent Pinchart
