Merge commit 'refs/for-upstream/mali-dp' of git://linux-arm.org/linux-ld into drm-next

"mali-dp driver changes for drm-next, includes the driver implementation
for writeback, improvements for power management handling in the driver
and a debugfs entry for reporting possible internal errors. Please pull
at your earliest convenience.

Boris Brezillon is also interested in this pull as he is going to change
slightly the parameter for the writeback connector's atomic_commit() and
he needs to fix the mali-dp driver in his series."

Signed-off-by: Dave Airlie <airlied@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180705144408.GH15340@e110455-lin.cambridge.arm.com

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

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);

drivers/gpu/drm/arm/malidp_drv.c

@@ -17,6 +17,7 @@
 #include <linux/of_graph.h>
 #include <linux/of_reserved_mem.h>
 #include <linux/pm_runtime.h>
+#include <linux/debugfs.h>
 
 #include <drm/drmP.h>
 #include <drm/drm_atomic.h>
@@ -31,6 +32,7 @@
 #include <drm/drm_of.h>
 
 #include "malidp_drv.h"
+#include "malidp_mw.h"
 #include "malidp_regs.h"
 #include "malidp_hw.h"
 
@@ -170,14 +172,15 @@ static int malidp_set_and_wait_config_valid(struct drm_device *drm)
 	struct malidp_hw_device *hwdev = malidp->dev;
 	int ret;
 
-	atomic_set(&malidp->config_valid, 0);
-	hwdev->hw->set_config_valid(hwdev);
+	hwdev->hw->set_config_valid(hwdev, 1);
 	/* don't wait for config_valid flag if we are in config mode */
-	if (hwdev->hw->in_config_mode(hwdev))
+	if (hwdev->hw->in_config_mode(hwdev)) {
+		atomic_set(&malidp->config_valid, MALIDP_CONFIG_VALID_DONE);
 		return 0;
+	}
 
 	ret = wait_event_interruptible_timeout(malidp->wq,
-			atomic_read(&malidp->config_valid) == 1,
+			atomic_read(&malidp->config_valid) == MALIDP_CONFIG_VALID_DONE,
 			msecs_to_jiffies(MALIDP_CONF_VALID_TIMEOUT));
 
 	return (ret > 0) ? 0 : -ETIMEDOUT;
@@ -216,12 +219,20 @@ static void malidp_atomic_commit_hw_done(struct drm_atomic_state *state)
 static void malidp_atomic_commit_tail(struct drm_atomic_state *state)
 {
 	struct drm_device *drm = state->dev;
+	struct malidp_drm *malidp = drm->dev_private;
 	struct drm_crtc *crtc;
 	struct drm_crtc_state *old_crtc_state;
 	int i;
 
 	pm_runtime_get_sync(drm->dev);
 
+	/*
+	 * set config_valid to a special value to let IRQ handlers
+	 * know that we are updating registers
+	 */
+	atomic_set(&malidp->config_valid, MALIDP_CONFIG_START);
+	malidp->dev->hw->set_config_valid(malidp->dev, 0);
+
 	drm_atomic_helper_commit_modeset_disables(drm, state);
 
 	for_each_old_crtc_in_state(state, crtc, old_crtc_state, i) {
@@ -230,7 +241,9 @@ 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);
 
@@ -268,12 +281,18 @@ 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)
@@ -285,6 +304,8 @@ static int malidp_irq_init(struct platform_device *pdev)
 {
 	int irq_de, irq_se, ret = 0;
 	struct drm_device *drm = dev_get_drvdata(&pdev->dev);
+	struct malidp_drm *malidp = drm->dev_private;
+	struct malidp_hw_device *hwdev = malidp->dev;
 
 	/* fetch the interrupts from DT */
 	irq_de = platform_get_irq_byname(pdev, "DE");
@@ -304,7 +325,7 @@ static int malidp_irq_init(struct platform_device *pdev)
 
 	ret = malidp_se_irq_init(drm, irq_se);
 	if (ret) {
-		malidp_de_irq_fini(drm);
+		malidp_de_irq_fini(hwdev);
 		return ret;
 	}
 
@@ -326,6 +347,106 @@ static int malidp_dumb_create(struct drm_file *file_priv,
 	return drm_gem_cma_dumb_create_internal(file_priv, drm, args);
 }
 
+#ifdef CONFIG_DEBUG_FS
+
+static void malidp_error_stats_init(struct malidp_error_stats *error_stats)
+{
+	error_stats->num_errors = 0;
+	error_stats->last_error_status = 0;
+	error_stats->last_error_vblank = -1;
+}
+
+void malidp_error(struct malidp_drm *malidp,
+		  struct malidp_error_stats *error_stats, u32 status,
+		  u64 vblank)
+{
+	unsigned long irqflags;
+
+	spin_lock_irqsave(&malidp->errors_lock, irqflags);
+	error_stats->last_error_status = status;
+	error_stats->last_error_vblank = vblank;
+	error_stats->num_errors++;
+	spin_unlock_irqrestore(&malidp->errors_lock, irqflags);
+}
+
+void malidp_error_stats_dump(const char *prefix,
+			     struct malidp_error_stats error_stats,
+			     struct seq_file *m)
+{
+	seq_printf(m, "[%s] num_errors : %d\n", prefix,
+		   error_stats.num_errors);
+	seq_printf(m, "[%s] last_error_status  : 0x%08x\n", prefix,
+		   error_stats.last_error_status);
+	seq_printf(m, "[%s] last_error_vblank : %lld\n", prefix,
+		   error_stats.last_error_vblank);
+}
+
+static int malidp_show_stats(struct seq_file *m, void *arg)
+{
+	struct drm_device *drm = m->private;
+	struct malidp_drm *malidp = drm->dev_private;
+	unsigned long irqflags;
+	struct malidp_error_stats de_errors, se_errors;
+
+	spin_lock_irqsave(&malidp->errors_lock, irqflags);
+	de_errors = malidp->de_errors;
+	se_errors = malidp->se_errors;
+	spin_unlock_irqrestore(&malidp->errors_lock, irqflags);
+	malidp_error_stats_dump("DE", de_errors, m);
+	malidp_error_stats_dump("SE", se_errors, m);
+	return 0;
+}
+
+static int malidp_debugfs_open(struct inode *inode, struct file *file)
+{
+	return single_open(file, malidp_show_stats, inode->i_private);
+}
+
+static ssize_t malidp_debugfs_write(struct file *file, const char __user *ubuf,
+				    size_t len, loff_t *offp)
+{
+	struct seq_file *m = file->private_data;
+	struct drm_device *drm = m->private;
+	struct malidp_drm *malidp = drm->dev_private;
+	unsigned long irqflags;
+
+	spin_lock_irqsave(&malidp->errors_lock, irqflags);
+	malidp_error_stats_init(&malidp->de_errors);
+	malidp_error_stats_init(&malidp->se_errors);
+	spin_unlock_irqrestore(&malidp->errors_lock, irqflags);
+	return len;
+}
+
+static const struct file_operations malidp_debugfs_fops = {
+	.owner = THIS_MODULE,
+	.open = malidp_debugfs_open,
+	.read = seq_read,
+	.write = malidp_debugfs_write,
+	.llseek = seq_lseek,
+	.release = single_release,
+};
+
+static int malidp_debugfs_init(struct drm_minor *minor)
+{
+	struct malidp_drm *malidp = minor->dev->dev_private;
+	struct dentry *dentry = NULL;
+
+	malidp_error_stats_init(&malidp->de_errors);
+	malidp_error_stats_init(&malidp->se_errors);
+	spin_lock_init(&malidp->errors_lock);
+	dentry = debugfs_create_file("debug",
+				     S_IRUGO | S_IWUSR,
+				     minor->debugfs_root, minor->dev,
+				     &malidp_debugfs_fops);
+	if (!dentry) {
+		DRM_ERROR("Cannot create debug file\n");
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+#endif //CONFIG_DEBUG_FS
+
 static struct drm_driver malidp_driver = {
 	.driver_features = DRIVER_GEM | DRIVER_MODESET | DRIVER_ATOMIC |
 			   DRIVER_PRIME,
@@ -342,6 +463,9 @@ static struct drm_driver malidp_driver = {
 	.gem_prime_vmap = drm_gem_cma_prime_vmap,
 	.gem_prime_vunmap = drm_gem_cma_prime_vunmap,
 	.gem_prime_mmap = drm_gem_cma_prime_mmap,
+#ifdef CONFIG_DEBUG_FS
+	.debugfs_init = malidp_debugfs_init,
+#endif
 	.fops = &fops,
 	.name = "mali-dp",
 	.desc = "ARM Mali Display Processor driver",
@@ -458,6 +582,8 @@ static int malidp_runtime_pm_suspend(struct device *dev)
 	/* we can only suspend if the hardware is in config mode */
 	WARN_ON(!hwdev->hw->in_config_mode(hwdev));
 
+	malidp_se_irq_fini(hwdev);
+	malidp_de_irq_fini(hwdev);
 	hwdev->pm_suspended = true;
 	clk_disable_unprepare(hwdev->mclk);
 	clk_disable_unprepare(hwdev->aclk);
@@ -476,6 +602,8 @@ static int malidp_runtime_pm_resume(struct device *dev)
 	clk_prepare_enable(hwdev->aclk);
 	clk_prepare_enable(hwdev->mclk);
 	hwdev->pm_suspended = false;
+	malidp_de_irq_hw_init(hwdev);
+	malidp_se_irq_hw_init(hwdev);
 
 	return 0;
 }
@@ -587,8 +715,9 @@ static int malidp_bind(struct device *dev)
 	for (i = 0; i < MAX_OUTPUT_CHANNELS; i++)
 		out_depth = (out_depth << 8) | (output_width[i] & 0xf);
 	malidp_hw_write(hwdev, out_depth, hwdev->hw->map.out_depth_base);
+	hwdev->output_color_depth = out_depth;
 
-	atomic_set(&malidp->config_valid, 0);
+	atomic_set(&malidp->config_valid, MALIDP_CONFIG_VALID_INIT);
 	init_waitqueue_head(&malidp->wq);
 
 	ret = malidp_init(drm);
@@ -641,8 +770,8 @@ register_fail:
 fbdev_fail:
 	pm_runtime_get_sync(dev);
 vblank_fail:
-	malidp_se_irq_fini(drm);
-	malidp_de_irq_fini(drm);
+	malidp_se_irq_fini(hwdev);
+	malidp_de_irq_fini(hwdev);
 	drm->irq_enabled = false;
 irq_init_fail:
 	drm_atomic_helper_shutdown(drm);
@@ -672,14 +801,15 @@ static void malidp_unbind(struct device *dev)
 {
 	struct drm_device *drm = dev_get_drvdata(dev);
 	struct malidp_drm *malidp = drm->dev_private;
+	struct malidp_hw_device *hwdev = malidp->dev;
 
 	drm_dev_unregister(drm);
 	drm_fb_cma_fbdev_fini(drm);
 	drm_kms_helper_poll_fini(drm);
 	pm_runtime_get_sync(dev);
 	drm_crtc_vblank_off(&malidp->crtc);
-	malidp_se_irq_fini(drm);
-	malidp_de_irq_fini(drm);
+	malidp_se_irq_fini(hwdev);
+	malidp_de_irq_fini(hwdev);
 	drm->irq_enabled = false;
 	drm_atomic_helper_shutdown(drm);
 	component_unbind_all(dev, drm);
@@ -752,8 +882,25 @@ static int __maybe_unused malidp_pm_resume(struct device *dev)
 	return 0;
 }
 
+static int __maybe_unused malidp_pm_suspend_late(struct device *dev)
+{
+	if (!pm_runtime_status_suspended(dev)) {
+		malidp_runtime_pm_suspend(dev);
+		pm_runtime_set_suspended(dev);
+	}
+	return 0;
+}
+
+static int __maybe_unused malidp_pm_resume_early(struct device *dev)
+{
+	malidp_runtime_pm_resume(dev);
+	pm_runtime_set_active(dev);
+	return 0;
+}
+
 static const struct dev_pm_ops malidp_pm_ops = {
 	SET_SYSTEM_SLEEP_PM_OPS(malidp_pm_suspend, malidp_pm_resume) \
+	SET_LATE_SYSTEM_SLEEP_PM_OPS(malidp_pm_suspend_late, malidp_pm_resume_early) \
 	SET_RUNTIME_PM_OPS(malidp_runtime_pm_suspend, malidp_runtime_pm_resume, NULL)
 };
 

drivers/gpu/drm/arm/malidp_drv.h

@@ -13,18 +13,38 @@
 #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 <linux/spinlock.h>
 #include <drm/drmP.h>
 #include "malidp_hw.h"
 
+#define MALIDP_CONFIG_VALID_INIT	0
+#define MALIDP_CONFIG_VALID_DONE	1
+#define MALIDP_CONFIG_START		0xd0
+
+struct malidp_error_stats {
+	s32 num_errors;
+	u32 last_error_status;
+	s64 last_error_vblank;
+};
+
 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;
 	u32 core_id;
+#ifdef CONFIG_DEBUG_FS
+	struct malidp_error_stats de_errors;
+	struct malidp_error_stats se_errors;
+	/* Protects errors stats */
+	spinlock_t errors_lock;
+#endif
 };
 
 #define crtc_to_malidp_device(x) container_of(x, struct malidp_drm, crtc)
@@ -62,6 +82,12 @@ struct malidp_crtc_state {
 int malidp_de_planes_init(struct drm_device *drm);
 int malidp_crtc_init(struct drm_device *drm);
 
+#ifdef CONFIG_DEBUG_FS
+void malidp_error(struct malidp_drm *malidp,
+		  struct malidp_error_stats *error_stats, u32 status,
+		  u64 vblank);
+#endif
+
 /* often used combination of rotational bits */
 #define MALIDP_ROTATED_MASK	(DRM_MODE_ROTATE_90 | DRM_MODE_ROTATE_270)
 

drivers/gpu/drm/arm/malidp_hw.c

@@ -21,15 +21,24 @@
 
 #include "malidp_drv.h"
 #include "malidp_hw.h"
+#include "malidp_mw.h"
+
+enum {
+	MW_NOT_ENABLED = 0,	/* SE writeback not enabled */
+	MW_ONESHOT,		/* SE in one-shot mode for writeback */
+	MW_START,		/* SE started writeback */
+	MW_RESTART,		/* SE will start another writeback after this one */
+	MW_STOP,		/* SE needs to stop after this writeback */
+};
 
 static const struct malidp_format_id malidp500_de_formats[] = {
 	/*    fourcc,   layers supporting the format,     internal id  */
-	{ DRM_FORMAT_ARGB2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  0 },
-	{ DRM_FORMAT_ABGR2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  1 },
+	{ DRM_FORMAT_ARGB2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2 | SE_MEMWRITE,  0 },
+	{ DRM_FORMAT_ABGR2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2 | SE_MEMWRITE,  1 },
 	{ DRM_FORMAT_ARGB8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  2 },
 	{ DRM_FORMAT_ABGR8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  3 },
-	{ DRM_FORMAT_XRGB8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  4 },
-	{ DRM_FORMAT_XBGR8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  5 },
+	{ DRM_FORMAT_XRGB8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2 | SE_MEMWRITE,  4 },
+	{ DRM_FORMAT_XBGR8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2 | SE_MEMWRITE,  5 },
 	{ DRM_FORMAT_RGB888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  6 },
 	{ DRM_FORMAT_BGR888, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  7 },
 	{ DRM_FORMAT_RGBA5551, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2,  8 },
@@ -38,7 +47,7 @@ static const struct malidp_format_id malidp500_de_formats[] = {
 	{ DRM_FORMAT_BGR565, DE_VIDEO1 | DE_GRAPHICS1 | DE_GRAPHICS2, 11 },
 	{ DRM_FORMAT_UYVY, DE_VIDEO1, 12 },
 	{ DRM_FORMAT_YUYV, DE_VIDEO1, 13 },
-	{ DRM_FORMAT_NV12, DE_VIDEO1, 14 },
+	{ DRM_FORMAT_NV12, DE_VIDEO1 | SE_MEMWRITE, 14 },
 	{ DRM_FORMAT_YUV420, DE_VIDEO1, 15 },
 };
 
@@ -47,27 +56,27 @@ static const struct malidp_format_id malidp500_de_formats[] = {
 
 #define MALIDP_COMMON_FORMATS \
 	/*    fourcc,   layers supporting the format,      internal id   */ \
-	{ DRM_FORMAT_ARGB2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(0, 0) }, \
-	{ DRM_FORMAT_ABGR2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(0, 1) }, \
-	{ DRM_FORMAT_RGBA1010102, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(0, 2) }, \
-	{ DRM_FORMAT_BGRA1010102, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(0, 3) }, \
+	{ DRM_FORMAT_ARGB2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | SE_MEMWRITE, MALIDP_ID(0, 0) }, \
+	{ DRM_FORMAT_ABGR2101010, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | SE_MEMWRITE, MALIDP_ID(0, 1) }, \
+	{ DRM_FORMAT_RGBA1010102, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | SE_MEMWRITE, MALIDP_ID(0, 2) }, \
+	{ DRM_FORMAT_BGRA1010102, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | SE_MEMWRITE, MALIDP_ID(0, 3) }, \
 	{ DRM_FORMAT_ARGB8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(1, 0) }, \
 	{ DRM_FORMAT_ABGR8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(1, 1) }, \
 	{ DRM_FORMAT_RGBA8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(1, 2) }, \
 	{ DRM_FORMAT_BGRA8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(1, 3) }, \
-	{ DRM_FORMAT_XRGB8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(2, 0) }, \
-	{ DRM_FORMAT_XBGR8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(2, 1) }, \
-	{ DRM_FORMAT_RGBX8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(2, 2) }, \
-	{ DRM_FORMAT_BGRX8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART, MALIDP_ID(2, 3) }, \
-	{ DRM_FORMAT_RGB888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(3, 0) }, \
-	{ DRM_FORMAT_BGR888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(3, 1) }, \
+	{ DRM_FORMAT_XRGB8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART | SE_MEMWRITE, MALIDP_ID(2, 0) }, \
+	{ DRM_FORMAT_XBGR8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART | SE_MEMWRITE, MALIDP_ID(2, 1) }, \
+	{ DRM_FORMAT_RGBX8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART | SE_MEMWRITE, MALIDP_ID(2, 2) }, \
+	{ DRM_FORMAT_BGRX8888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | DE_SMART | SE_MEMWRITE, MALIDP_ID(2, 3) }, \
+	{ DRM_FORMAT_RGB888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | SE_MEMWRITE, MALIDP_ID(3, 0) }, \
+	{ DRM_FORMAT_BGR888, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2 | SE_MEMWRITE, MALIDP_ID(3, 1) }, \
 	{ DRM_FORMAT_RGBA5551, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(4, 0) }, \
 	{ DRM_FORMAT_ABGR1555, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(4, 1) }, \
 	{ DRM_FORMAT_RGB565, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(4, 2) }, \
 	{ DRM_FORMAT_BGR565, DE_VIDEO1 | DE_GRAPHICS1 | DE_VIDEO2, MALIDP_ID(4, 3) }, \
 	{ DRM_FORMAT_YUYV, DE_VIDEO1 | DE_VIDEO2, MALIDP_ID(5, 2) },	\
 	{ DRM_FORMAT_UYVY, DE_VIDEO1 | DE_VIDEO2, MALIDP_ID(5, 3) },	\
-	{ DRM_FORMAT_NV12, DE_VIDEO1 | DE_VIDEO2, MALIDP_ID(5, 6) },	\
+	{ DRM_FORMAT_NV12, DE_VIDEO1 | DE_VIDEO2 | SE_MEMWRITE, MALIDP_ID(5, 6) },	\
 	{ DRM_FORMAT_YUV420, DE_VIDEO1 | DE_VIDEO2, MALIDP_ID(5, 7) }
 
 static const struct malidp_format_id malidp550_de_formats[] = {
@@ -223,15 +232,20 @@ static bool malidp500_in_config_mode(struct malidp_hw_device *hwdev)
 	return false;
 }
 
-static void malidp500_set_config_valid(struct malidp_hw_device *hwdev)
+static void malidp500_set_config_valid(struct malidp_hw_device *hwdev, u8 value)
 {
-	malidp_hw_setbits(hwdev, MALIDP_CFG_VALID, MALIDP500_CONFIG_VALID);
+	if (value)
+		malidp_hw_setbits(hwdev, MALIDP_CFG_VALID, MALIDP500_CONFIG_VALID);
+	else
+		malidp_hw_clearbits(hwdev, MALIDP_CFG_VALID, MALIDP500_CONFIG_VALID);
 }
 
 static void malidp500_modeset(struct malidp_hw_device *hwdev, struct videomode *mode)
 {
 	u32 val = 0;
 
+	malidp_hw_write(hwdev, hwdev->output_color_depth,
+		hwdev->hw->map.out_depth_base);
 	malidp_hw_clearbits(hwdev, MALIDP500_DC_CLEAR_MASK, MALIDP500_DC_CONTROL);
 	if (mode->flags & DISPLAY_FLAGS_HSYNC_HIGH)
 		val |= MALIDP500_HSYNCPOL;
@@ -368,6 +382,55 @@ static long malidp500_se_calc_mclk(struct malidp_hw_device *hwdev,
 	return ret;
 }
 
+static int malidp500_enable_memwrite(struct malidp_hw_device *hwdev,
+				     dma_addr_t *addrs, s32 *pitches,
+				     int num_planes, u16 w, u16 h, u32 fmt_id)
+{
+	u32 base = MALIDP500_SE_MEMWRITE_BASE;
+	u32 de_base = malidp_get_block_base(hwdev, MALIDP_DE_BLOCK);
+
+	/* enable the scaling engine block */
+	malidp_hw_setbits(hwdev, MALIDP_SCALE_ENGINE_EN, de_base + MALIDP_DE_DISPLAY_FUNC);
+
+	/* restart the writeback if already enabled */
+	if (hwdev->mw_state != MW_NOT_ENABLED)
+		hwdev->mw_state = MW_RESTART;
+	else
+		hwdev->mw_state = MW_START;
+
+	malidp_hw_write(hwdev, fmt_id, base + MALIDP_MW_FORMAT);
+	switch (num_planes) {
+	case 2:
+		malidp_hw_write(hwdev, lower_32_bits(addrs[1]), base + MALIDP_MW_P2_PTR_LOW);
+		malidp_hw_write(hwdev, upper_32_bits(addrs[1]), base + MALIDP_MW_P2_PTR_HIGH);
+		malidp_hw_write(hwdev, pitches[1], base + MALIDP_MW_P2_STRIDE);
+		/* fall through */
+	case 1:
+		malidp_hw_write(hwdev, lower_32_bits(addrs[0]), base + MALIDP_MW_P1_PTR_LOW);
+		malidp_hw_write(hwdev, upper_32_bits(addrs[0]), base + MALIDP_MW_P1_PTR_HIGH);
+		malidp_hw_write(hwdev, pitches[0], base + MALIDP_MW_P1_STRIDE);
+		break;
+	default:
+		WARN(1, "Invalid number of planes");
+	}
+
+	malidp_hw_write(hwdev, MALIDP_DE_H_ACTIVE(w) | MALIDP_DE_V_ACTIVE(h),
+			MALIDP500_SE_MEMWRITE_OUT_SIZE);
+	malidp_hw_setbits(hwdev, MALIDP_SE_MEMWRITE_EN, MALIDP500_SE_CONTROL);
+
+	return 0;
+}
+
+static void malidp500_disable_memwrite(struct malidp_hw_device *hwdev)
+{
+	u32 base = malidp_get_block_base(hwdev, MALIDP_DE_BLOCK);
+
+	if (hwdev->mw_state == MW_START || hwdev->mw_state == MW_RESTART)
+		hwdev->mw_state = MW_STOP;
+	malidp_hw_clearbits(hwdev, MALIDP_SE_MEMWRITE_EN, MALIDP500_SE_CONTROL);
+	malidp_hw_clearbits(hwdev, MALIDP_SCALE_ENGINE_EN, base + MALIDP_DE_DISPLAY_FUNC);
+}
+
 static int malidp550_query_hw(struct malidp_hw_device *hwdev)
 {
 	u32 conf = malidp_hw_read(hwdev, MALIDP550_CONFIG_ID);
@@ -447,15 +510,20 @@ static bool malidp550_in_config_mode(struct malidp_hw_device *hwdev)
 	return false;
 }
 
-static void malidp550_set_config_valid(struct malidp_hw_device *hwdev)
+static void malidp550_set_config_valid(struct malidp_hw_device *hwdev, u8 value)
 {
-	malidp_hw_setbits(hwdev, MALIDP_CFG_VALID, MALIDP550_CONFIG_VALID);
+	if (value)
+		malidp_hw_setbits(hwdev, MALIDP_CFG_VALID, MALIDP550_CONFIG_VALID);
+	else
+		malidp_hw_clearbits(hwdev, MALIDP_CFG_VALID, MALIDP550_CONFIG_VALID);
 }
 
 static void malidp550_modeset(struct malidp_hw_device *hwdev, struct videomode *mode)
 {
 	u32 val = MALIDP_DE_DEFAULT_PREFETCH_START;
 
+	malidp_hw_write(hwdev, hwdev->output_color_depth,
+		hwdev->hw->map.out_depth_base);
 	malidp_hw_write(hwdev, val, MALIDP550_DE_CONTROL);
 	/*
 	 * Mali-DP550 and Mali-DP650 encode the background color like this:
@@ -588,6 +656,51 @@ static long malidp550_se_calc_mclk(struct malidp_hw_device *hwdev,
 	return ret;
 }
 
+static int malidp550_enable_memwrite(struct malidp_hw_device *hwdev,
+				     dma_addr_t *addrs, s32 *pitches,
+				     int num_planes, u16 w, u16 h, u32 fmt_id)
+{
+	u32 base = MALIDP550_SE_MEMWRITE_BASE;
+	u32 de_base = malidp_get_block_base(hwdev, MALIDP_DE_BLOCK);
+
+	/* enable the scaling engine block */
+	malidp_hw_setbits(hwdev, MALIDP_SCALE_ENGINE_EN, de_base + MALIDP_DE_DISPLAY_FUNC);
+
+	hwdev->mw_state = MW_ONESHOT;
+
+	malidp_hw_write(hwdev, fmt_id, base + MALIDP_MW_FORMAT);
+	switch (num_planes) {
+	case 2:
+		malidp_hw_write(hwdev, lower_32_bits(addrs[1]), base + MALIDP_MW_P2_PTR_LOW);
+		malidp_hw_write(hwdev, upper_32_bits(addrs[1]), base + MALIDP_MW_P2_PTR_HIGH);
+		malidp_hw_write(hwdev, pitches[1], base + MALIDP_MW_P2_STRIDE);
+		/* fall through */
+	case 1:
+		malidp_hw_write(hwdev, lower_32_bits(addrs[0]), base + MALIDP_MW_P1_PTR_LOW);
+		malidp_hw_write(hwdev, upper_32_bits(addrs[0]), base + MALIDP_MW_P1_PTR_HIGH);
+		malidp_hw_write(hwdev, pitches[0], base + MALIDP_MW_P1_STRIDE);
+		break;
+	default:
+		WARN(1, "Invalid number of planes");
+	}
+
+	malidp_hw_write(hwdev, MALIDP_DE_H_ACTIVE(w) | MALIDP_DE_V_ACTIVE(h),
+			MALIDP550_SE_MEMWRITE_OUT_SIZE);
+	malidp_hw_setbits(hwdev, MALIDP550_SE_MEMWRITE_ONESHOT | MALIDP_SE_MEMWRITE_EN,
+			  MALIDP550_SE_CONTROL);
+
+	return 0;
+}
+
+static void malidp550_disable_memwrite(struct malidp_hw_device *hwdev)
+{
+	u32 base = malidp_get_block_base(hwdev, MALIDP_DE_BLOCK);
+
+	malidp_hw_clearbits(hwdev, MALIDP550_SE_MEMWRITE_ONESHOT | MALIDP_SE_MEMWRITE_EN,
+			    MALIDP550_SE_CONTROL);
+	malidp_hw_clearbits(hwdev, MALIDP_SCALE_ENGINE_EN, base + MALIDP_DE_DISPLAY_FUNC);
+}
+
 static int malidp650_query_hw(struct malidp_hw_device *hwdev)
 {
 	u32 conf = malidp_hw_read(hwdev, MALIDP550_CONFIG_ID);
@@ -632,11 +745,18 @@ const struct malidp_hw malidp_device[MALIDP_MAX_DEVICES] = {
 					    MALIDP500_DE_IRQ_VSYNC |
 					    MALIDP500_DE_IRQ_GLOBAL,
 				.vsync_irq = MALIDP500_DE_IRQ_VSYNC,
+				.err_mask = MALIDP_DE_IRQ_UNDERRUN |
+					    MALIDP500_DE_IRQ_AXI_ERR |
+					    MALIDP500_DE_IRQ_SATURATION,
 			},
 			.se_irq_map = {
 				.irq_mask = MALIDP500_SE_IRQ_CONF_MODE |
+					    MALIDP500_SE_IRQ_CONF_VALID |
 					    MALIDP500_SE_IRQ_GLOBAL,
-				.vsync_irq = 0,
+				.vsync_irq = MALIDP500_SE_IRQ_CONF_VALID,
+				.err_mask = MALIDP500_SE_IRQ_INIT_BUSY |
+					    MALIDP500_SE_IRQ_AXI_ERROR |
+					    MALIDP500_SE_IRQ_OVERRUN,
 			},
 			.dc_irq_map = {
 				.irq_mask = MALIDP500_DE_IRQ_CONF_VALID,
@@ -655,6 +775,8 @@ const struct malidp_hw malidp_device[MALIDP_MAX_DEVICES] = {
 		.rotmem_required = malidp500_rotmem_required,
 		.se_set_scaling_coeffs = malidp500_se_set_scaling_coeffs,
 		.se_calc_mclk = malidp500_se_calc_mclk,
+		.enable_memwrite = malidp500_enable_memwrite,
+		.disable_memwrite = malidp500_disable_memwrite,
 		.features = MALIDP_DEVICE_LV_HAS_3_STRIDES,
 	},
 	[MALIDP_550] = {
@@ -670,13 +792,20 @@ const struct malidp_hw malidp_device[MALIDP_MAX_DEVICES] = {
 				.irq_mask = MALIDP_DE_IRQ_UNDERRUN |
 					    MALIDP550_DE_IRQ_VSYNC,
 				.vsync_irq = MALIDP550_DE_IRQ_VSYNC,
+				.err_mask = MALIDP_DE_IRQ_UNDERRUN |
+					    MALIDP550_DE_IRQ_SATURATION |
+					    MALIDP550_DE_IRQ_AXI_ERR,
 			},
 			.se_irq_map = {
-				.irq_mask = MALIDP550_SE_IRQ_EOW |
-					    MALIDP550_SE_IRQ_AXI_ERR,
+				.irq_mask = MALIDP550_SE_IRQ_EOW,
+				.vsync_irq = MALIDP550_SE_IRQ_EOW,
+				.err_mask  = MALIDP550_SE_IRQ_AXI_ERR |
+					     MALIDP550_SE_IRQ_OVR |
+					     MALIDP550_SE_IRQ_IBSY,
 			},
 			.dc_irq_map = {
-				.irq_mask = MALIDP550_DC_IRQ_CONF_VALID,
+				.irq_mask = MALIDP550_DC_IRQ_CONF_VALID |
+					    MALIDP550_DC_IRQ_SE,
 				.vsync_irq = MALIDP550_DC_IRQ_CONF_VALID,
 			},
 			.pixel_formats = malidp550_de_formats,
@@ -692,6 +821,8 @@ const struct malidp_hw malidp_device[MALIDP_MAX_DEVICES] = {
 		.rotmem_required = malidp550_rotmem_required,
 		.se_set_scaling_coeffs = malidp550_se_set_scaling_coeffs,
 		.se_calc_mclk = malidp550_se_calc_mclk,
+		.enable_memwrite = malidp550_enable_memwrite,
+		.disable_memwrite = malidp550_disable_memwrite,
 		.features = 0,
 	},
 	[MALIDP_650] = {
@@ -708,13 +839,25 @@ const struct malidp_hw malidp_device[MALIDP_MAX_DEVICES] = {
 					    MALIDP650_DE_IRQ_DRIFT |
 					    MALIDP550_DE_IRQ_VSYNC,
 				.vsync_irq = MALIDP550_DE_IRQ_VSYNC,
+				.err_mask = MALIDP_DE_IRQ_UNDERRUN |
+					    MALIDP650_DE_IRQ_DRIFT |
+					    MALIDP550_DE_IRQ_SATURATION |
+					    MALIDP550_DE_IRQ_AXI_ERR |
+					    MALIDP650_DE_IRQ_ACEV1 |
+					    MALIDP650_DE_IRQ_ACEV2 |
+					    MALIDP650_DE_IRQ_ACEG |
+					    MALIDP650_DE_IRQ_AXIEP,
 			},
 			.se_irq_map = {
-				.irq_mask = MALIDP550_SE_IRQ_EOW |
-					    MALIDP550_SE_IRQ_AXI_ERR,
+				.irq_mask = MALIDP550_SE_IRQ_EOW,
+				.vsync_irq = MALIDP550_SE_IRQ_EOW,
+				.err_mask = MALIDP550_SE_IRQ_AXI_ERR |
+					    MALIDP550_SE_IRQ_OVR |
+					    MALIDP550_SE_IRQ_IBSY,
 			},
 			.dc_irq_map = {
-				.irq_mask = MALIDP550_DC_IRQ_CONF_VALID,
+				.irq_mask = MALIDP550_DC_IRQ_CONF_VALID |
+					    MALIDP550_DC_IRQ_SE,
 				.vsync_irq = MALIDP550_DC_IRQ_CONF_VALID,
 			},
 			.pixel_formats = malidp550_de_formats,
@@ -730,6 +873,8 @@ const struct malidp_hw malidp_device[MALIDP_MAX_DEVICES] = {
 		.rotmem_required = malidp550_rotmem_required,
 		.se_set_scaling_coeffs = malidp550_se_set_scaling_coeffs,
 		.se_calc_mclk = malidp550_se_calc_mclk,
+		.enable_memwrite = malidp550_enable_memwrite,
+		.disable_memwrite = malidp550_disable_memwrite,
 		.features = 0,
 	},
 };
@@ -791,7 +936,7 @@ static irqreturn_t malidp_de_irq(int irq, void *arg)
 			malidp->event = NULL;
 			spin_unlock(&drm->event_lock);
 		}
-		atomic_set(&malidp->config_valid, 1);
+		atomic_set(&malidp->config_valid, MALIDP_CONFIG_VALID_DONE);
 		ret = IRQ_WAKE_THREAD;
 	}
 
@@ -800,10 +945,17 @@ static irqreturn_t malidp_de_irq(int irq, void *arg)
 		return ret;
 
 	mask = malidp_hw_read(hwdev, MALIDP_REG_MASKIRQ);
-	status &= mask;
+	/* keep the status of the enabled interrupts, plus the error bits */
+	status &= (mask | de->err_mask);
 	if ((status & de->vsync_irq) && malidp->crtc.enabled)
 		drm_crtc_handle_vblank(&malidp->crtc);
 
+#ifdef CONFIG_DEBUG_FS
+	if (status & de->err_mask) {
+		malidp_error(malidp, &malidp->de_errors, status,
+			     drm_crtc_vblank_count(&malidp->crtc));
+	}
+#endif
 	malidp_hw_clear_irq(hwdev, MALIDP_DE_BLOCK, status);
 
 	return (ret == IRQ_NONE) ? IRQ_HANDLED : ret;
@@ -819,6 +971,23 @@ static irqreturn_t malidp_de_irq_thread_handler(int irq, void *arg)
 	return IRQ_HANDLED;
 }
 
+void malidp_de_irq_hw_init(struct malidp_hw_device *hwdev)
+{
+	/* ensure interrupts are disabled */
+	malidp_hw_disable_irq(hwdev, MALIDP_DE_BLOCK, 0xffffffff);
+	malidp_hw_clear_irq(hwdev, MALIDP_DE_BLOCK, 0xffffffff);
+	malidp_hw_disable_irq(hwdev, MALIDP_DC_BLOCK, 0xffffffff);
+	malidp_hw_clear_irq(hwdev, MALIDP_DC_BLOCK, 0xffffffff);
+
+	/* first enable the DC block IRQs */
+	malidp_hw_enable_irq(hwdev, MALIDP_DC_BLOCK,
+			     hwdev->hw->map.dc_irq_map.irq_mask);
+
+	/* now enable the DE block IRQs */
+	malidp_hw_enable_irq(hwdev, MALIDP_DE_BLOCK,
+			     hwdev->hw->map.de_irq_map.irq_mask);
+}
+
 int malidp_de_irq_init(struct drm_device *drm, int irq)
 {
 	struct malidp_drm *malidp = drm->dev_private;
@@ -839,22 +1008,13 @@ int malidp_de_irq_init(struct drm_device *drm, int irq)
 		return ret;
 	}
 
-	/* first enable the DC block IRQs */
-	malidp_hw_enable_irq(hwdev, MALIDP_DC_BLOCK,
-			     hwdev->hw->map.dc_irq_map.irq_mask);
-
-	/* now enable the DE block IRQs */
-	malidp_hw_enable_irq(hwdev, MALIDP_DE_BLOCK,
-			     hwdev->hw->map.de_irq_map.irq_mask);
+	malidp_de_irq_hw_init(hwdev);
 
 	return 0;
 }
 
-void malidp_de_irq_fini(struct drm_device *drm)
+void malidp_de_irq_fini(struct malidp_hw_device *hwdev)
 {
-	struct malidp_drm *malidp = drm->dev_private;
-	struct malidp_hw_device *hwdev = malidp->dev;
-
 	malidp_hw_disable_irq(hwdev, MALIDP_DE_BLOCK,
 			      hwdev->hw->map.de_irq_map.irq_mask);
 	malidp_hw_disable_irq(hwdev, MALIDP_DC_BLOCK,
@@ -879,19 +1039,61 @@ static irqreturn_t malidp_se_irq(int irq, void *arg)
 		return IRQ_NONE;
 
 	status = malidp_hw_read(hwdev, hw->map.se_base + MALIDP_REG_STATUS);
-	if (!(status & se->irq_mask))
+	if (!(status & (se->irq_mask | se->err_mask)))
 		return IRQ_NONE;
 
+#ifdef CONFIG_DEBUG_FS
+	if (status & se->err_mask)
+		malidp_error(malidp, &malidp->se_errors, status,
+			     drm_crtc_vblank_count(&malidp->crtc));
+#endif
 	mask = malidp_hw_read(hwdev, hw->map.se_base + MALIDP_REG_MASKIRQ);
-	status = malidp_hw_read(hwdev, hw->map.se_base + MALIDP_REG_STATUS);
 	status &= mask;
-	/* ToDo: status decoding and firing up of VSYNC and page flip events */
+
+	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;
+		case MW_RESTART:
+			drm_writeback_signal_completion(&malidp->mw_connector, 0);
+			/* fall through to a new start */
+		case MW_START:
+			/* writeback started, need to emulate one-shot mode */
+			hw->disable_memwrite(hwdev);
+			/*
+			 * only set config_valid HW bit if there is no other update
+			 * in progress or if we raced ahead of the DE IRQ handler
+			 * and config_valid flag will not be update until later
+			 */
+			status = malidp_hw_read(hwdev, hw->map.dc_base + MALIDP_REG_STATUS);
+			if ((atomic_read(&malidp->config_valid) != MALIDP_CONFIG_START) ||
+			    (status & hw->map.dc_irq_map.vsync_irq))
+				hw->set_config_valid(hwdev, 1);
+			break;
+		}
+	}
 
 	malidp_hw_clear_irq(hwdev, MALIDP_SE_BLOCK, status);
 
 	return IRQ_HANDLED;
 }
 
+void malidp_se_irq_hw_init(struct malidp_hw_device *hwdev)
+{
+	/* ensure interrupts are disabled */
+	malidp_hw_disable_irq(hwdev, MALIDP_SE_BLOCK, 0xffffffff);
+	malidp_hw_clear_irq(hwdev, MALIDP_SE_BLOCK, 0xffffffff);
+
+	malidp_hw_enable_irq(hwdev, MALIDP_SE_BLOCK,
+			     hwdev->hw->map.se_irq_map.irq_mask);
+}
+
 static irqreturn_t malidp_se_irq_thread_handler(int irq, void *arg)
 {
 	return IRQ_HANDLED;
@@ -915,17 +1117,14 @@ int malidp_se_irq_init(struct drm_device *drm, int irq)
 		return ret;
 	}
 
-	malidp_hw_enable_irq(hwdev, MALIDP_SE_BLOCK,
-			     hwdev->hw->map.se_irq_map.irq_mask);
+	hwdev->mw_state = MW_NOT_ENABLED;
+	malidp_se_irq_hw_init(hwdev);
 
 	return 0;
 }
 
-void malidp_se_irq_fini(struct drm_device *drm)
+void malidp_se_irq_fini(struct malidp_hw_device *hwdev)
 {
-	struct malidp_drm *malidp = drm->dev_private;
-	struct malidp_hw_device *hwdev = malidp->dev;
-
 	malidp_hw_disable_irq(hwdev, MALIDP_SE_BLOCK,
 			      hwdev->hw->map.se_irq_map.irq_mask);
 }

drivers/gpu/drm/arm/malidp_hw.h

@@ -33,6 +33,7 @@ enum {
 	DE_GRAPHICS2 = BIT(2), /* used only in DP500 */
 	DE_VIDEO2 = BIT(3),
 	DE_SMART = BIT(4),
+	SE_MEMWRITE = BIT(5),
 };
 
 struct malidp_format_id {
@@ -52,6 +53,7 @@ struct malidp_format_id {
 struct malidp_irq_map {
 	u32 irq_mask;		/* mask of IRQs that can be enabled in the block */
 	u32 vsync_irq;		/* IRQ bit used for signaling during VSYNC */
+	u32 err_mask;		/* mask of bits that represent errors */
 };
 
 struct malidp_layer {
@@ -151,12 +153,13 @@ struct malidp_hw {
 	bool (*in_config_mode)(struct malidp_hw_device *hwdev);
 
 	/*
-	 * Set configuration valid flag for hardware parameters that can
-	 * be changed outside the configuration mode. Hardware will use
-	 * the new settings when config valid is set after the end of the
-	 * current buffer scanout
+	 * Set/clear configuration valid flag for hardware parameters that can
+	 * be changed outside the configuration mode to the given value.
+	 * Hardware will use the new settings when config valid is set,
+	 * after the end of the current buffer scanout, and will ignore
+	 * any new values for those parameters if config valid flag is cleared
 	 */
-	void (*set_config_valid)(struct malidp_hw_device *hwdev);
+	void (*set_config_valid)(struct malidp_hw_device *hwdev, u8 value);
 
 	/*
 	 * Set a new mode in hardware. Requires the hardware to be in
@@ -177,6 +180,23 @@ struct malidp_hw {
 	long (*se_calc_mclk)(struct malidp_hw_device *hwdev,
 			     struct malidp_se_config *se_config,
 			     struct videomode *vm);
+	/*
+	 * Enable writing to memory the content of the next frame
+	 * @param hwdev - malidp_hw_device structure containing the HW description
+	 * @param addrs - array of addresses for each plane
+	 * @param pitches - array of pitches for each plane
+	 * @param num_planes - number of planes to be written
+	 * @param w - width of the output frame
+	 * @param h - height of the output frame
+	 * @param fmt_id - internal format ID of output buffer
+	 */
+	int (*enable_memwrite)(struct malidp_hw_device *hwdev, dma_addr_t *addrs,
+			       s32 *pitches, int num_planes, u16 w, u16 h, u32 fmt_id);
+
+	/*
+	 * Disable the writing to memory of the next frame's content.
+	 */
+	void (*disable_memwrite)(struct malidp_hw_device *hwdev);
 
 	u8 features;
 };
@@ -210,10 +230,14 @@ struct malidp_hw_device {
 
 	u8 min_line_size;
 	u16 max_line_size;
+	u32 output_color_depth;
 
 	/* track the device PM state */
 	bool pm_suspended;
 
+	/* track the SE memory writeback state */
+	u8 mw_state;
+
 	/* size of memory used for rotating layers, up to two banks available */
 	u32 rotation_memory[2];
 };
@@ -279,9 +303,11 @@ static inline void malidp_hw_enable_irq(struct malidp_hw_device *hwdev,
 }
 
 int malidp_de_irq_init(struct drm_device *drm, int irq);
-void malidp_de_irq_fini(struct drm_device *drm);
+void malidp_se_irq_hw_init(struct malidp_hw_device *hwdev);
+void malidp_de_irq_hw_init(struct malidp_hw_device *hwdev);
+void malidp_de_irq_fini(struct malidp_hw_device *hwdev);
 int malidp_se_irq_init(struct drm_device *drm, int irq);
-void malidp_se_irq_fini(struct drm_device *drm);
+void malidp_se_irq_fini(struct malidp_hw_device *hwdev);
 
 u8 malidp_hw_get_format_id(const struct malidp_hw_regmap *map,
 			   u8 layer_id, u32 format);

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@arm.com>
+ *
+ * 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);
+	}
+}

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@arm.com>
+ *
+ */
+
+#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

drivers/gpu/drm/arm/malidp_regs.h

@@ -53,6 +53,8 @@
 #define MALIDP550_DE_IRQ_AXI_ERR		(1 << 16)
 #define MALIDP550_SE_IRQ_EOW			(1 << 0)
 #define MALIDP550_SE_IRQ_AXI_ERR		(1 << 16)
+#define MALIDP550_SE_IRQ_OVR			(1 << 17)
+#define MALIDP550_SE_IRQ_IBSY			(1 << 18)
 #define MALIDP550_DC_IRQ_CONF_VALID		(1 << 0)
 #define MALIDP550_DC_IRQ_CONF_MODE		(1 << 4)
 #define MALIDP550_DC_IRQ_CONF_ACTIVE		(1 << 16)
@@ -60,12 +62,18 @@
 #define MALIDP550_DC_IRQ_SE			(1 << 24)
 
 #define MALIDP650_DE_IRQ_DRIFT			(1 << 4)
+#define MALIDP650_DE_IRQ_ACEV1			(1 << 17)
+#define MALIDP650_DE_IRQ_ACEV2			(1 << 18)
+#define MALIDP650_DE_IRQ_ACEG			(1 << 19)
+#define MALIDP650_DE_IRQ_AXIEP			(1 << 28)
 
 /* bit masks that are common between products */
 #define   MALIDP_CFG_VALID		(1 << 0)
 #define   MALIDP_DISP_FUNC_GAMMA	(1 << 0)
 #define   MALIDP_DISP_FUNC_CADJ		(1 << 4)
 #define   MALIDP_DISP_FUNC_ILACED	(1 << 8)
+#define   MALIDP_SCALE_ENGINE_EN	(1 << 16)
+#define   MALIDP_SE_MEMWRITE_EN		(2 << 5)
 
 /* register offsets for IRQ management */
 #define MALIDP_REG_STATUS		0x00000
@@ -153,6 +161,16 @@
 		(((x) & MALIDP_SE_ENH_LIMIT_MASK) << 16)
 #define   MALIDP_SE_ENH_COEFF0			0x04
 
+
+/* register offsets relative to MALIDP5x0_SE_MEMWRITE_BASE */
+#define MALIDP_MW_FORMAT		0x00000
+#define MALIDP_MW_P1_STRIDE		0x00004
+#define MALIDP_MW_P2_STRIDE		0x00008
+#define MALIDP_MW_P1_PTR_LOW		0x0000c
+#define MALIDP_MW_P1_PTR_HIGH		0x00010
+#define MALIDP_MW_P2_PTR_LOW		0x0002c
+#define MALIDP_MW_P2_PTR_HIGH		0x00030
+
 /* register offsets and bits specific to DP500 */
 #define MALIDP500_ADDR_SPACE_SIZE	0x01000
 #define MALIDP500_DC_BASE		0x00000
@@ -186,7 +204,8 @@
 #define MALIDP500_DE_LG2_PTR_BASE	0x0031c
 #define MALIDP500_SE_BASE		0x00c00
 #define MALIDP500_SE_CONTROL		0x00c0c
-#define MALIDP500_SE_PTR_BASE		0x00e0c
+#define MALIDP500_SE_MEMWRITE_OUT_SIZE	0x00c2c
+#define MALIDP500_SE_MEMWRITE_BASE	0x00e00
 #define MALIDP500_DC_IRQ_BASE		0x00f00
 #define MALIDP500_CONFIG_VALID		0x00f00
 #define MALIDP500_CONFIG_ID		0x00fd4
@@ -217,6 +236,9 @@
 #define MALIDP550_DE_PERF_BASE		0x00500
 #define MALIDP550_SE_BASE		0x08000
 #define MALIDP550_SE_CONTROL		0x08010
+#define   MALIDP550_SE_MEMWRITE_ONESHOT	(1 << 7)
+#define MALIDP550_SE_MEMWRITE_OUT_SIZE	0x08030
+#define MALIDP550_SE_MEMWRITE_BASE	0x08100
 #define MALIDP550_DC_BASE		0x0c000
 #define MALIDP550_DC_CONTROL		0x0c010
 #define   MALIDP550_DC_CONFIG_REQ	(1 << 16)

drivers/gpu/drm/drm_atomic.c

@@ -1436,6 +1436,10 @@ 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);
 }