[PATCH v8 5/5] drm: mali-dp: Add writeback connector

From: Liviu Dudau
Date: Tue Jun 12 2018 - 10:08:42 EST


From: Brian Starkey <brian.starkey@xxxxxxx>

Mali-DP has a memory writeback engine which can be used to write the
composition result to a memory buffer. Expose this functionality as a
DRM writeback connector on supported hardware.

Changes since v1:
Daniel Vetter:
- Don't require a modeset when writeback routing changes
- Make writeback connector always disconnected

Changes since v2:
- Rebase onto new drm_writeback_connector
- Add reset callback, allocating subclassed state
Daniel Vetter:
- Squash out-fence support into this commit
Gustavo Padovan:
- Don't signal fence directly from driver (and drop malidp_mw_job)

Changes since v3:
- Modifications to fit with Mali-DP commit tail changes

Signed-off-by: Brian Starkey <brian.starkey@xxxxxxx>
[rebased and fixed conflicts]
Signed-off-by: Mihail Atanassov <mihail.atanassov@xxxxxxx>
Signed-off-by: Liviu Dudau <liviu.dudau@xxxxxxx>
---
drivers/gpu/drm/arm/Makefile | 1 +
drivers/gpu/drm/arm/malidp_crtc.c | 10 ++
drivers/gpu/drm/arm/malidp_drv.c | 19 ++-
drivers/gpu/drm/arm/malidp_drv.h | 3 +
drivers/gpu/drm/arm/malidp_hw.c | 5 +
drivers/gpu/drm/arm/malidp_mw.c | 250 ++++++++++++++++++++++++++++++
drivers/gpu/drm/arm/malidp_mw.h | 14 ++
drivers/gpu/drm/drm_atomic.c | 4 +
8 files changed, 301 insertions(+), 5 deletions(-)
create mode 100644 drivers/gpu/drm/arm/malidp_mw.c
create mode 100644 drivers/gpu/drm/arm/malidp_mw.h

diff --git a/drivers/gpu/drm/arm/Makefile b/drivers/gpu/drm/arm/Makefile
index bb8b158ff90d0..3bf31d1a4722c 100644
--- a/drivers/gpu/drm/arm/Makefile
+++ b/drivers/gpu/drm/arm/Makefile
@@ -1,4 +1,5 @@
hdlcd-y := hdlcd_drv.o hdlcd_crtc.o
obj-$(CONFIG_DRM_HDLCD) += hdlcd.o
mali-dp-y := malidp_drv.o malidp_hw.o malidp_planes.o malidp_crtc.o
+mali-dp-y += malidp_mw.o
obj-$(CONFIG_DRM_MALI_DISPLAY) += mali-dp.o
diff --git a/drivers/gpu/drm/arm/malidp_crtc.c b/drivers/gpu/drm/arm/malidp_crtc.c
index fcc62bc60f6a7..ef44202fb43f8 100644
--- a/drivers/gpu/drm/arm/malidp_crtc.c
+++ b/drivers/gpu/drm/arm/malidp_crtc.c
@@ -411,6 +411,16 @@ static int malidp_crtc_atomic_check(struct drm_crtc *crtc,
}
}

+ /* If only the writeback routing has changed, we don't need a modeset */
+ if (state->connectors_changed) {
+ u32 old_mask = crtc->state->connector_mask;
+ u32 new_mask = state->connector_mask;
+
+ if ((old_mask ^ new_mask) ==
+ (1 << drm_connector_index(&malidp->mw_connector.base)))
+ state->connectors_changed = false;
+ }
+
ret = malidp_crtc_atomic_check_gamma(crtc, state);
ret = ret ? ret : malidp_crtc_atomic_check_ctm(crtc, state);
ret = ret ? ret : malidp_crtc_atomic_check_scaling(crtc, state);
diff --git a/drivers/gpu/drm/arm/malidp_drv.c b/drivers/gpu/drm/arm/malidp_drv.c
index e262620ffed55..fc264554c5035 100644
--- a/drivers/gpu/drm/arm/malidp_drv.c
+++ b/drivers/gpu/drm/arm/malidp_drv.c
@@ -31,6 +31,7 @@
#include <drm/drm_of.h>

#include "malidp_drv.h"
+#include "malidp_mw.h"
#include "malidp_regs.h"
#include "malidp_hw.h"

@@ -238,7 +239,9 @@ static void malidp_atomic_commit_tail(struct drm_atomic_state *state)
malidp_atomic_commit_se_config(crtc, old_crtc_state);
}

- drm_atomic_helper_commit_planes(drm, state, 0);
+ drm_atomic_helper_commit_planes(drm, state, DRM_PLANE_COMMIT_ACTIVE_ONLY);
+
+ malidp_mw_atomic_commit(drm, state);

drm_atomic_helper_commit_modeset_enables(drm, state);

@@ -276,12 +279,18 @@ static int malidp_init(struct drm_device *drm)
drm->mode_config.helper_private = &malidp_mode_config_helpers;

ret = malidp_crtc_init(drm);
- if (ret) {
- drm_mode_config_cleanup(drm);
- return ret;
- }
+ if (ret)
+ goto crtc_fail;
+
+ ret = malidp_mw_connector_init(drm);
+ if (ret)
+ goto crtc_fail;

return 0;
+
+crtc_fail:
+ drm_mode_config_cleanup(drm);
+ return ret;
}

static void malidp_fini(struct drm_device *drm)
diff --git a/drivers/gpu/drm/arm/malidp_drv.h b/drivers/gpu/drm/arm/malidp_drv.h
index e8c41cf1b5bd2..5febd4b43e058 100644
--- a/drivers/gpu/drm/arm/malidp_drv.h
+++ b/drivers/gpu/drm/arm/malidp_drv.h
@@ -13,6 +13,8 @@
#ifndef __MALIDP_DRV_H__
#define __MALIDP_DRV_H__

+#include <drm/drm_writeback.h>
+#include <drm/drm_encoder.h>
#include <linux/mutex.h>
#include <linux/wait.h>
#include <drm/drmP.h>
@@ -25,6 +27,7 @@
struct malidp_drm {
struct malidp_hw_device *dev;
struct drm_crtc crtc;
+ struct drm_writeback_connector mw_connector;
wait_queue_head_t wq;
struct drm_pending_vblank_event *event;
atomic_t config_valid;
diff --git a/drivers/gpu/drm/arm/malidp_hw.c b/drivers/gpu/drm/arm/malidp_hw.c
index df3649203e6a9..e0de7a35a0beb 100644
--- a/drivers/gpu/drm/arm/malidp_hw.c
+++ b/drivers/gpu/drm/arm/malidp_hw.c
@@ -21,6 +21,7 @@

#include "malidp_drv.h"
#include "malidp_hw.h"
+#include "malidp_mw.h"

enum {
MW_NOT_ENABLED = 0, /* SE writeback not enabled */
@@ -995,7 +996,11 @@ static irqreturn_t malidp_se_irq(int irq, void *arg)

if (status & se->vsync_irq) {
switch (hwdev->mw_state) {
+ case MW_ONESHOT:
+ drm_writeback_signal_completion(&malidp->mw_connector, 0);
+ break;
case MW_STOP:
+ drm_writeback_signal_completion(&malidp->mw_connector, 0);
/* disable writeback after stop */
hwdev->mw_state = MW_NOT_ENABLED;
break;
diff --git a/drivers/gpu/drm/arm/malidp_mw.c b/drivers/gpu/drm/arm/malidp_mw.c
new file mode 100644
index 0000000000000..cfd718e7e97c1
--- /dev/null
+++ b/drivers/gpu/drm/arm/malidp_mw.c
@@ -0,0 +1,250 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * (C) COPYRIGHT 2016 ARM Limited. All rights reserved.
+ * Author: Brian Starkey <brian.starkey@xxxxxxx>
+ *
+ * ARM Mali DP Writeback connector implementation
+ */
+#include <drm/drm_atomic.h>
+#include <drm/drm_atomic_helper.h>
+#include <drm/drm_crtc.h>
+#include <drm/drm_crtc_helper.h>
+#include <drm/drm_fb_cma_helper.h>
+#include <drm/drm_gem_cma_helper.h>
+#include <drm/drmP.h>
+#include <drm/drm_writeback.h>
+
+#include "malidp_drv.h"
+#include "malidp_hw.h"
+#include "malidp_mw.h"
+
+#define to_mw_state(_state) (struct malidp_mw_connector_state *)(_state)
+
+struct malidp_mw_connector_state {
+ struct drm_connector_state base;
+ dma_addr_t addrs[2];
+ s32 pitches[2];
+ u8 format;
+ u8 n_planes;
+};
+
+static int malidp_mw_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 enum drm_mode_status
+malidp_mw_connector_mode_valid(struct drm_connector *connector,
+ struct drm_display_mode *mode)
+{
+ struct drm_device *dev = connector->dev;
+ struct drm_mode_config *mode_config = &dev->mode_config;
+ int w = mode->hdisplay, h = mode->vdisplay;
+
+ if ((w < mode_config->min_width) || (w > mode_config->max_width))
+ return MODE_BAD_HVALUE;
+
+ if ((h < mode_config->min_height) || (h > mode_config->max_height))
+ return MODE_BAD_VVALUE;
+
+ return MODE_OK;
+}
+
+const struct drm_connector_helper_funcs malidp_mw_connector_helper_funcs = {
+ .get_modes = malidp_mw_connector_get_modes,
+ .mode_valid = malidp_mw_connector_mode_valid,
+};
+
+static void malidp_mw_connector_reset(struct drm_connector *connector)
+{
+ struct malidp_mw_connector_state *mw_state =
+ kzalloc(sizeof(*mw_state), GFP_KERNEL);
+
+ if (connector->state)
+ __drm_atomic_helper_connector_destroy_state(connector->state);
+
+ kfree(connector->state);
+ __drm_atomic_helper_connector_reset(connector, &mw_state->base);
+}
+
+static enum drm_connector_status
+malidp_mw_connector_detect(struct drm_connector *connector, bool force)
+{
+ return connector_status_disconnected;
+}
+
+static void malidp_mw_connector_destroy(struct drm_connector *connector)
+{
+ drm_connector_cleanup(connector);
+}
+
+static struct drm_connector_state *
+malidp_mw_connector_duplicate_state(struct drm_connector *connector)
+{
+ struct malidp_mw_connector_state *mw_state;
+
+ if (WARN_ON(!connector->state))
+ return NULL;
+
+ mw_state = kzalloc(sizeof(*mw_state), GFP_KERNEL);
+ if (!mw_state)
+ return NULL;
+
+ /* No need to preserve any of our driver-local data */
+ __drm_atomic_helper_connector_duplicate_state(connector, &mw_state->base);
+
+ return &mw_state->base;
+}
+
+static const struct drm_connector_funcs malidp_mw_connector_funcs = {
+ .reset = malidp_mw_connector_reset,
+ .detect = malidp_mw_connector_detect,
+ .fill_modes = drm_helper_probe_single_connector_modes,
+ .destroy = malidp_mw_connector_destroy,
+ .atomic_duplicate_state = malidp_mw_connector_duplicate_state,
+ .atomic_destroy_state = drm_atomic_helper_connector_destroy_state,
+};
+
+static int
+malidp_mw_encoder_atomic_check(struct drm_encoder *encoder,
+ struct drm_crtc_state *crtc_state,
+ struct drm_connector_state *conn_state)
+{
+ struct malidp_mw_connector_state *mw_state = to_mw_state(conn_state);
+ struct malidp_drm *malidp = encoder->dev->dev_private;
+ struct drm_framebuffer *fb;
+ int i, n_planes;
+
+ if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
+ return 0;
+
+ fb = conn_state->writeback_job->fb;
+ if ((fb->width != crtc_state->mode.hdisplay) ||
+ (fb->height != crtc_state->mode.vdisplay)) {
+ DRM_DEBUG_KMS("Invalid framebuffer size %ux%u\n",
+ fb->width, fb->height);
+ return -EINVAL;
+ }
+
+ mw_state->format =
+ malidp_hw_get_format_id(&malidp->dev->hw->map, SE_MEMWRITE,
+ fb->format->format);
+ if (mw_state->format == MALIDP_INVALID_FORMAT_ID) {
+ struct drm_format_name_buf format_name;
+
+ DRM_DEBUG_KMS("Invalid pixel format %s\n",
+ drm_get_format_name(fb->format->format,
+ &format_name));
+ return -EINVAL;
+ }
+
+ n_planes = drm_format_num_planes(fb->format->format);
+ for (i = 0; i < n_planes; i++) {
+ struct drm_gem_cma_object *obj = drm_fb_cma_get_gem_obj(fb, i);
+ /* memory write buffers are never rotated */
+ u8 alignment = malidp_hw_get_pitch_align(malidp->dev, 0);
+
+ if (fb->pitches[i] & (alignment - 1)) {
+ DRM_DEBUG_KMS("Invalid pitch %u for plane %d\n",
+ fb->pitches[i], i);
+ return -EINVAL;
+ }
+ mw_state->pitches[i] = fb->pitches[i];
+ mw_state->addrs[i] = obj->paddr + fb->offsets[i];
+ }
+ mw_state->n_planes = n_planes;
+
+ return 0;
+}
+
+static const struct drm_encoder_helper_funcs malidp_mw_encoder_helper_funcs = {
+ .atomic_check = malidp_mw_encoder_atomic_check,
+};
+
+static u32 *get_writeback_formats(struct malidp_drm *malidp, int *n_formats)
+{
+ const struct malidp_hw_regmap *map = &malidp->dev->hw->map;
+ u32 *formats;
+ int n, i;
+
+ formats = kcalloc(map->n_pixel_formats, sizeof(*formats),
+ GFP_KERNEL);
+ if (!formats)
+ return NULL;
+
+ for (n = 0, i = 0; i < map->n_pixel_formats; i++) {
+ if (map->pixel_formats[i].layer & SE_MEMWRITE)
+ formats[n++] = map->pixel_formats[i].format;
+ }
+
+ *n_formats = n;
+
+ return formats;
+}
+
+int malidp_mw_connector_init(struct drm_device *drm)
+{
+ struct malidp_drm *malidp = drm->dev_private;
+ u32 *formats;
+ int ret, n_formats;
+
+ if (!malidp->dev->hw->enable_memwrite)
+ return 0;
+
+ malidp->mw_connector.encoder.possible_crtcs = 1 << drm_crtc_index(&malidp->crtc);
+ drm_connector_helper_add(&malidp->mw_connector.base,
+ &malidp_mw_connector_helper_funcs);
+
+ formats = get_writeback_formats(malidp, &n_formats);
+ if (!formats)
+ return -ENOMEM;
+
+ ret = drm_writeback_connector_init(drm, &malidp->mw_connector,
+ &malidp_mw_connector_funcs,
+ &malidp_mw_encoder_helper_funcs,
+ formats, n_formats);
+ kfree(formats);
+ if (ret)
+ return ret;
+
+ return 0;
+}
+
+void malidp_mw_atomic_commit(struct drm_device *drm,
+ struct drm_atomic_state *old_state)
+{
+ struct malidp_drm *malidp = drm->dev_private;
+ struct drm_writeback_connector *mw_conn = &malidp->mw_connector;
+ struct drm_connector_state *conn_state = mw_conn->base.state;
+ struct malidp_hw_device *hwdev = malidp->dev;
+ struct malidp_mw_connector_state *mw_state;
+
+ if (!conn_state)
+ return;
+
+ mw_state = to_mw_state(conn_state);
+
+ if (conn_state->writeback_job && conn_state->writeback_job->fb) {
+ struct drm_framebuffer *fb = conn_state->writeback_job->fb;
+
+ DRM_DEV_DEBUG_DRIVER(drm->dev,
+ "Enable memwrite %ux%u:%d %pad fmt: %u\n",
+ fb->width, fb->height,
+ mw_state->pitches[0],
+ &mw_state->addrs[0],
+ mw_state->format);
+
+ drm_writeback_queue_job(mw_conn, conn_state->writeback_job);
+ conn_state->writeback_job = NULL;
+
+ hwdev->hw->enable_memwrite(hwdev, mw_state->addrs,
+ mw_state->pitches, mw_state->n_planes,
+ fb->width, fb->height, mw_state->format);
+ } else {
+ DRM_DEV_DEBUG_DRIVER(drm->dev, "Disable memwrite\n");
+ hwdev->hw->disable_memwrite(hwdev);
+ }
+}
diff --git a/drivers/gpu/drm/arm/malidp_mw.h b/drivers/gpu/drm/arm/malidp_mw.h
new file mode 100644
index 0000000000000..19a007676a1db
--- /dev/null
+++ b/drivers/gpu/drm/arm/malidp_mw.h
@@ -0,0 +1,14 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * (C) COPYRIGHT 2016 ARM Limited. All rights reserved.
+ * Author: Brian Starkey <brian.starkey@xxxxxxx>
+ *
+ */
+
+#ifndef __MALIDP_MW_H__
+#define __MALIDP_MW_H__
+
+int malidp_mw_connector_init(struct drm_device *drm);
+void malidp_mw_atomic_commit(struct drm_device *drm,
+ struct drm_atomic_state *old_state);
+#endif
diff --git a/drivers/gpu/drm/drm_atomic.c b/drivers/gpu/drm/drm_atomic.c
index db3cb47da31b6..da80ca611d918 100644
--- a/drivers/gpu/drm/drm_atomic.c
+++ b/drivers/gpu/drm/drm_atomic.c
@@ -1390,6 +1390,10 @@ static void drm_atomic_connector_print_state(struct drm_printer *p,
drm_printf(p, "connector[%u]: %s\n", connector->base.id, connector->name);
drm_printf(p, "\tcrtc=%s\n", state->crtc ? state->crtc->name : "(null)");

+ if (connector->connector_type == DRM_MODE_CONNECTOR_WRITEBACK)
+ if (state->writeback_job && state->writeback_job->fb)
+ drm_printf(p, "\tfb=%d\n", state->writeback_job->fb->base.id);
+
if (connector->funcs->atomic_print_state)
connector->funcs->atomic_print_state(p, state);
}
--
2.17.1