~lkcamp/patches

Add new formats support to vkms v5 PROPOSED

Summary
=======
This series of patches refactor some vkms components in order to introduce
new formats to the planes and writeback connector.

Now in the blend function, the plane's pixels are converted to ARGB16161616
and then blended together.

The CRC is calculated based on the ARGB1616161616 buffer. And if required,
this buffer is copied/converted to the writeback buffer format.

And to handle the pixel conversion, new functions were added to convert
from a specific format to ARGB16161616 (the reciprocal is also true).

Tests
=====
This patch series was tested using the following igt tests:
-t ".*kms_plane.*"
-t ".*kms_writeback.*"
-t ".*kms_cursor_crc*"
-t ".*kms_flip.*"

New tests passing
-------------------
- pipe-A-cursor-size-change
- pipe-A-cursor-alpha-transparent

Performance
-----------
It's running slightly faster than the current implementation.

Results running the IGT[1] test
`igt@kms_cursor_crc@pipe-a-cursor-512x512-onscreen` ten times:

|                  Frametime                   |
|:--------------------------------------------:|
|  Implementation |  Current  |   This commit  |
|:---------------:|:---------:|:--------------:|
| frametime range |  9~22 ms  |     10~22 ms   |
|     Average     |  11.4 ms  |     12.32 ms   |

Memory consumption
==================
It consumes less memory than the current implementation in
the common case (more detail in the commit message).

| Memory consumption (output dimensions) |
|:--------------------------------------:|
|       Current      |     This patch    |
|:------------------:|:-----------------:|
|   Width * Heigth   |     2 * Width     |

[1] IGT commit id: bc3f6833a12221a46659535dac06ebb312490eb4

XRGB to ARGB behavior
=====================
During the development, I decided to always fill the alpha channel of
the output pixel whenever the conversion from a format without an alpha
channel to ARGB16161616 is necessary. Therefore, I ignore the value
received from the XRGB and overwrite the value with 0xFFFF.

Primary plane and CRTC size
===========================
This patch series reworks the blend function to accept a primary plane with
a different size and position from CRTC.
Because now we need to fill the background, we had a loss in
performance with this change

---
Igor Torrente (9):
  drm: vkms: Alloc the compose frame using vzalloc
  drm: vkms: Replace hardcoded value of `vkms_composer.map` to
    DRM_FORMAT_MAX_PLANES
  drm: vkms: Rename `vkms_composer` to `vkms_frame_info`
  drm: drm_atomic_helper: Add a new helper to deal with the writeback
    connector validation
  drm: vkms: Add fb information to `vkms_writeback_job`
  drm: vkms: Refactor the plane composer to accept new formats
  drm: vkms: Supports to the case where primary plane doesn't match the
    CRTC
  drm: vkms: Adds XRGB_16161616 and ARGB_1616161616 formats
  drm: vkms: Add support to the RGB565 format

 Documentation/gpu/vkms.rst            |  13 +-
 drivers/gpu/drm/drm_atomic_helper.c   |  39 ++++
 drivers/gpu/drm/vkms/Makefile         |   1 +
 drivers/gpu/drm/vkms/vkms_composer.c  | 325 ++++++++++++--------------
 drivers/gpu/drm/vkms/vkms_crtc.c      |   4 +
 drivers/gpu/drm/vkms/vkms_drv.h       |  41 +++-
 drivers/gpu/drm/vkms/vkms_formats.c   | 298 +++++++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_formats.h   |  12 +
 drivers/gpu/drm/vkms/vkms_plane.c     |  50 ++--
 drivers/gpu/drm/vkms/vkms_writeback.c |  35 ++-
 include/drm/drm_atomic_helper.h       |   3 +
 11 files changed, 596 insertions(+), 225 deletions(-)
 create mode 100644 drivers/gpu/drm/vkms/vkms_formats.c
 create mode 100644 drivers/gpu/drm/vkms/vkms_formats.h

-- 
2.30.2
Hi Igor,

Thanks for your patch!

Às 17:45 de 04/04/22, Igor Torrente escreveu:
Next
Às 17:45 de 04/04/22, Igor Torrente escreveu:
Next
Hi

Am 04.04.22 um 22:45 schrieb Igor Torrente:
Next
Hi André,

On 4/5/22 11:05, André Almeida wrote:
Next
Hi André,

On 4/5/22 11:21, André Almeida wrote:
Next
Hi Pekka,

On 4/20/22 08:23, Pekka Paalanen wrote:
Next
Hi Pekka,

On 4/20/22 09:36, Pekka Paalanen wrote:
Next
Hi Pekka,

On 4/20/22 10:13, Pekka Paalanen wrote:
Next
Hi Pekka,

On 4/21/22 07:58, Pekka Paalanen wrote:
Next
I forgot to respond some points from your review.

On 4/23/22 13:04, Igor Torrente wrote:
Next
Hi Pekka,

On 4/25/22 04:56, Pekka Paalanen wrote:
Next
Hi Pekka,

On 4/25/22 05:10, Pekka Paalanen wrote:
Next
Hi Pekka,

On 4/27/22 04:55, Pekka Paalanen wrote:
Next
Hi Thomas

On 5/7/22 04:32, Thomas Zimmermann wrote:
Next
Hi Melissa,

On 6/13/22 06:52, Melissa Wen wrote:
Next
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[PATCH v5 1/9] drm: vkms: Alloc the compose frame using vzalloc Export this patch

Currently, the memory to the composition frame is being allocated using
the kzmalloc. This comes with the limitation of maximum size of one
page size(which in the x86_64 is 4Kb and 4MB for default and hugepage
respectively).

Somes test of igt (e.g. kms_plane@pixel-format) uses more than 4MB when
testing some pixel formats like ARGB16161616 and the following error were
showing up when running kms_plane@plane-panning-bottom-right*:

[drm:vkms_composer_worker [vkms]] *ERROR* Cannot allocate memory for
output frame.

This problem is addessed by allocating the memory using kvzalloc that
circunvents this limitation.
V5: Improve the commit message and drop the debugging issues in VKMS
TO-DO(Melissa Wen).
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 Documentation/gpu/vkms.rst           | 6 ------
 drivers/gpu/drm/vkms/vkms_composer.c | 6 +++---
 2 files changed, 3 insertions(+), 9 deletions(-)

diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
index 9c873c3912cc..973e2d43108b 100644
--- a/Documentation/gpu/vkms.rst
+++ b/Documentation/gpu/vkms.rst
@@ -102,12 +102,6 @@ Debugging:

- kms_plane: some test cases are failing due to timeout on capturing CRC;

- kms_flip: when running test cases in sequence, some successful individual
  test cases are failing randomly; when individually, some successful test
  cases display in the log the following error::

  [drm:vkms_prepare_fb [vkms]] ERROR vmap failed: -4

Virtual hardware (vblank-less) mode:

- VKMS already has support for vblanks simulated via hrtimers, which can be
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 9e8204be9a14..82f79e508f81 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -180,7 +180,7 @@ static int compose_active_planes(void **vaddr_out,
	int i;

	if (!*vaddr_out) {
		*vaddr_out = kzalloc(gem_obj->size, GFP_KERNEL);
		*vaddr_out = kvzalloc(gem_obj->size, GFP_KERNEL);
		if (!*vaddr_out) {
			DRM_ERROR("Cannot allocate memory for output frame.");
			return -ENOMEM;
@@ -263,7 +263,7 @@ void vkms_composer_worker(struct work_struct *work)
				    crtc_state);
	if (ret) {
		if (ret == -EINVAL && !wb_pending)
			kfree(vaddr_out);
			kvfree(vaddr_out);
		return;
	}

@@ -275,7 +275,7 @@ void vkms_composer_worker(struct work_struct *work)
		crtc_state->wb_pending = false;
		spin_unlock_irq(&out->composer_lock);
	} else {
		kfree(vaddr_out);
		kvfree(vaddr_out);
	}

	/*
-- 
2.30.2
Hi Igor,

Thanks for your patch!

Às 17:45 de 04/04/22, Igor Torrente escreveu:

[PATCH v5 2/9] drm: vkms: Replace hardcoded value of `vkms_composer.map` to DRM_FORMAT_MAX_PLANES Export this patch

The `map` vector at `vkms_composer` uses a hardcoded value to define its
size.

If someday the maximum number of planes increases, this hardcoded value
can be a problem.

This value is being replaced with the DRM_FORMAT_MAX_PLANES macro.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_drv.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index 9496fdc900b8..0eeea6f93733 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -30,7 +30,7 @@ struct vkms_writeback_job {
struct vkms_composer {
	struct drm_framebuffer fb;
	struct drm_rect src, dst;
	struct dma_buf_map map[4];
	struct dma_buf_map map[DRM_FORMAT_MAX_PLANES];
	unsigned int offset;
	unsigned int pitch;
	unsigned int cpp;
-- 
2.30.2

[PATCH v5 3/9] drm: vkms: Rename `vkms_composer` to `vkms_frame_info` Export this patch

Changes the name of this struct to a more meaningful name.
A name that represents better what this struct is about.

Composer is the code that do the compositing of the planes.
This struct contains information on the frame used in the output
composition. Thus, vkms_frame_info is a better name to represent
this.

V5: Fix a commit message typo(Melissa Wen).

Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_composer.c | 87 ++++++++++++++--------------
 drivers/gpu/drm/vkms/vkms_drv.h      |  6 +-
 drivers/gpu/drm/vkms/vkms_plane.c    | 38 ++++++------
 3 files changed, 66 insertions(+), 65 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 82f79e508f81..2d946368a561 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -11,11 +11,11 @@
#include "vkms_drv.h"

static u32 get_pixel_from_buffer(int x, int y, const u8 *buffer,
				 const struct vkms_composer *composer)
				 const struct vkms_frame_info *frame_info)
{
	u32 pixel;
	int src_offset = composer->offset + (y * composer->pitch)
				      + (x * composer->cpp);
	int src_offset = frame_info->offset + (y * frame_info->pitch)
					    + (x * frame_info->cpp);

	pixel = *(u32 *)&buffer[src_offset];

@@ -26,24 +26,24 @@ static u32 get_pixel_from_buffer(int x, int y, const u8 *buffer,
 * compute_crc - Compute CRC value on output frame
 *
 * @vaddr: address to final framebuffer
 * @composer: framebuffer's metadata
 * @frame_info: framebuffer's metadata
 *
 * returns CRC value computed using crc32 on the visible portion of
 * the final framebuffer at vaddr_out
 */
static uint32_t compute_crc(const u8 *vaddr,
			    const struct vkms_composer *composer)
			    const struct vkms_frame_info *frame_info)
{
	int x, y;
	u32 crc = 0, pixel = 0;
	int x_src = composer->src.x1 >> 16;
	int y_src = composer->src.y1 >> 16;
	int h_src = drm_rect_height(&composer->src) >> 16;
	int w_src = drm_rect_width(&composer->src) >> 16;
	int x_src = frame_info->src.x1 >> 16;
	int y_src = frame_info->src.y1 >> 16;
	int h_src = drm_rect_height(&frame_info->src) >> 16;
	int w_src = drm_rect_width(&frame_info->src) >> 16;

	for (y = y_src; y < y_src + h_src; ++y) {
		for (x = x_src; x < x_src + w_src; ++x) {
			pixel = get_pixel_from_buffer(x, y, vaddr, composer);
			pixel = get_pixel_from_buffer(x, y, vaddr, frame_info);
			crc = crc32_le(crc, (void *)&pixel, sizeof(u32));
		}
	}
@@ -98,8 +98,8 @@ static void x_blend(const u8 *xrgb_src, u8 *xrgb_dst)
 * blend - blend value at vaddr_src with value at vaddr_dst
 * @vaddr_dst: destination address
 * @vaddr_src: source address
 * @dst_composer: destination framebuffer's metadata
 * @src_composer: source framebuffer's metadata
 * @dst_frame_info: destination framebuffer's metadata
 * @src_frame_info: source framebuffer's metadata
 * @pixel_blend: blending equation based on plane format
 *
 * Blend the vaddr_src value with the vaddr_dst value using a pixel blend
@@ -111,33 +111,33 @@ static void x_blend(const u8 *xrgb_src, u8 *xrgb_dst)
 * pixel color values
 */
static void blend(void *vaddr_dst, void *vaddr_src,
		  struct vkms_composer *dst_composer,
		  struct vkms_composer *src_composer,
		  struct vkms_frame_info *dst_frame_info,
		  struct vkms_frame_info *src_frame_info,
		  void (*pixel_blend)(const u8 *, u8 *))
{
	int i, j, j_dst, i_dst;
	int offset_src, offset_dst;
	u8 *pixel_dst, *pixel_src;

	int x_src = src_composer->src.x1 >> 16;
	int y_src = src_composer->src.y1 >> 16;
	int x_src = src_frame_info->src.x1 >> 16;
	int y_src = src_frame_info->src.y1 >> 16;

	int x_dst = src_composer->dst.x1;
	int y_dst = src_composer->dst.y1;
	int h_dst = drm_rect_height(&src_composer->dst);
	int w_dst = drm_rect_width(&src_composer->dst);
	int x_dst = src_frame_info->dst.x1;
	int y_dst = src_frame_info->dst.y1;
	int h_dst = drm_rect_height(&src_frame_info->dst);
	int w_dst = drm_rect_width(&src_frame_info->dst);

	int y_limit = y_src + h_dst;
	int x_limit = x_src + w_dst;

	for (i = y_src, i_dst = y_dst; i < y_limit; ++i) {
		for (j = x_src, j_dst = x_dst; j < x_limit; ++j) {
			offset_dst = dst_composer->offset
				     + (i_dst * dst_composer->pitch)
				     + (j_dst++ * dst_composer->cpp);
			offset_src = src_composer->offset
				     + (i * src_composer->pitch)
				     + (j * src_composer->cpp);
			offset_dst = dst_frame_info->offset
				     + (i_dst * dst_frame_info->pitch)
				     + (j_dst++ * dst_frame_info->cpp);
			offset_src = src_frame_info->offset
				     + (i * src_frame_info->pitch)
				     + (j * src_frame_info->cpp);

			pixel_src = (u8 *)(vaddr_src + offset_src);
			pixel_dst = (u8 *)(vaddr_dst + offset_dst);
@@ -149,32 +149,33 @@ static void blend(void *vaddr_dst, void *vaddr_src,
	}
}

static void compose_plane(struct vkms_composer *primary_composer,
			  struct vkms_composer *plane_composer,
static void compose_plane(struct vkms_frame_info *primary_plane_info,
			  struct vkms_frame_info *plane_frame_info,
			  void *vaddr_out)
{
	struct drm_framebuffer *fb = &plane_composer->fb;
	struct drm_framebuffer *fb = &plane_frame_info->fb;
	void *vaddr;
	void (*pixel_blend)(const u8 *p_src, u8 *p_dst);

	if (WARN_ON(dma_buf_map_is_null(&primary_composer->map[0])))
	if (WARN_ON(dma_buf_map_is_null(&primary_plane_info->map[0])))
		return;

	vaddr = plane_composer->map[0].vaddr;
	vaddr = plane_frame_info->map[0].vaddr;

	if (fb->format->format == DRM_FORMAT_ARGB8888)
		pixel_blend = &alpha_blend;
	else
		pixel_blend = &x_blend;

	blend(vaddr_out, vaddr, primary_composer, plane_composer, pixel_blend);
	blend(vaddr_out, vaddr, primary_plane_info,
	      plane_frame_info, pixel_blend);
}

static int compose_active_planes(void **vaddr_out,
				 struct vkms_composer *primary_composer,
				 struct vkms_frame_info *primary_plane_info,
				 struct vkms_crtc_state *crtc_state)
{
	struct drm_framebuffer *fb = &primary_composer->fb;
	struct drm_framebuffer *fb = &primary_plane_info->fb;
	struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0);
	const void *vaddr;
	int i;
@@ -187,10 +188,10 @@ static int compose_active_planes(void **vaddr_out,
		}
	}

	if (WARN_ON(dma_buf_map_is_null(&primary_composer->map[0])))
	if (WARN_ON(dma_buf_map_is_null(&primary_plane_info->map[0])))
		return -EINVAL;

	vaddr = primary_composer->map[0].vaddr;
	vaddr = primary_plane_info->map[0].vaddr;

	memcpy(*vaddr_out, vaddr, gem_obj->size);

@@ -199,8 +200,8 @@ static int compose_active_planes(void **vaddr_out,
	 * ((primary <- overlay) <- cursor)
	 */
	for (i = 1; i < crtc_state->num_active_planes; i++)
		compose_plane(primary_composer,
			      crtc_state->active_planes[i]->composer,
		compose_plane(primary_plane_info,
			      crtc_state->active_planes[i]->frame_info,
			      *vaddr_out);

	return 0;
@@ -222,7 +223,7 @@ void vkms_composer_worker(struct work_struct *work)
						composer_work);
	struct drm_crtc *crtc = crtc_state->base.crtc;
	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
	struct vkms_composer *primary_composer = NULL;
	struct vkms_frame_info *primary_plane_info = NULL;
	struct vkms_plane_state *act_plane = NULL;
	bool crc_pending, wb_pending;
	void *vaddr_out = NULL;
@@ -250,16 +251,16 @@ void vkms_composer_worker(struct work_struct *work)
	if (crtc_state->num_active_planes >= 1) {
		act_plane = crtc_state->active_planes[0];
		if (act_plane->base.base.plane->type == DRM_PLANE_TYPE_PRIMARY)
			primary_composer = act_plane->composer;
			primary_plane_info = act_plane->frame_info;
	}

	if (!primary_composer)
	if (!primary_plane_info)
		return;

	if (wb_pending)
		vaddr_out = crtc_state->active_writeback->data[0].vaddr;

	ret = compose_active_planes(&vaddr_out, primary_composer,
	ret = compose_active_planes(&vaddr_out, primary_plane_info,
				    crtc_state);
	if (ret) {
		if (ret == -EINVAL && !wb_pending)
@@ -267,7 +268,7 @@ void vkms_composer_worker(struct work_struct *work)
		return;
	}

	crc32 = compute_crc(vaddr_out, primary_composer);
	crc32 = compute_crc(vaddr_out, primary_plane_info);

	if (wb_pending) {
		drm_writeback_signal_completion(&out->wb_connector, 0);
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index 0eeea6f93733..2e6342164bef 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -27,7 +27,7 @@ struct vkms_writeback_job {
	struct dma_buf_map data[DRM_FORMAT_MAX_PLANES];
};

struct vkms_composer {
struct vkms_frame_info {
	struct drm_framebuffer fb;
	struct drm_rect src, dst;
	struct dma_buf_map map[DRM_FORMAT_MAX_PLANES];
@@ -39,11 +39,11 @@ struct vkms_composer {
/**
 * vkms_plane_state - Driver specific plane state
 * @base: base plane state
 * @composer: data required for composing computation
 * @frame_info: data required for composing computation
 */
struct vkms_plane_state {
	struct drm_shadow_plane_state base;
	struct vkms_composer *composer;
	struct vkms_frame_info *frame_info;
};

struct vkms_plane {
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index 32409e15244b..a56b0f76eddd 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -24,20 +24,20 @@ static struct drm_plane_state *
vkms_plane_duplicate_state(struct drm_plane *plane)
{
	struct vkms_plane_state *vkms_state;
	struct vkms_composer *composer;
	struct vkms_frame_info *frame_info;

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

	composer = kzalloc(sizeof(*composer), GFP_KERNEL);
	if (!composer) {
		DRM_DEBUG_KMS("Couldn't allocate composer\n");
	frame_info = kzalloc(sizeof(*frame_info), GFP_KERNEL);
	if (!frame_info) {
		DRM_DEBUG_KMS("Couldn't allocate frame_info\n");
		kfree(vkms_state);
		return NULL;
	}

	vkms_state->composer = composer;
	vkms_state->frame_info = frame_info;

	__drm_gem_duplicate_shadow_plane_state(plane, &vkms_state->base);

@@ -54,12 +54,12 @@ static void vkms_plane_destroy_state(struct drm_plane *plane,
		/* dropping the reference we acquired in
		 * vkms_primary_plane_update()
		 */
		if (drm_framebuffer_read_refcount(&vkms_state->composer->fb))
			drm_framebuffer_put(&vkms_state->composer->fb);
		if (drm_framebuffer_read_refcount(&vkms_state->frame_info->fb))
			drm_framebuffer_put(&vkms_state->frame_info->fb);
	}

	kfree(vkms_state->composer);
	vkms_state->composer = NULL;
	kfree(vkms_state->frame_info);
	vkms_state->frame_info = NULL;

	__drm_gem_destroy_shadow_plane_state(&vkms_state->base);
	kfree(vkms_state);
@@ -99,7 +99,7 @@ static void vkms_plane_atomic_update(struct drm_plane *plane,
	struct vkms_plane_state *vkms_plane_state;
	struct drm_shadow_plane_state *shadow_plane_state;
	struct drm_framebuffer *fb = new_state->fb;
	struct vkms_composer *composer;
	struct vkms_frame_info *frame_info;

	if (!new_state->crtc || !fb)
		return;
@@ -107,15 +107,15 @@ static void vkms_plane_atomic_update(struct drm_plane *plane,
	vkms_plane_state = to_vkms_plane_state(new_state);
	shadow_plane_state = &vkms_plane_state->base;

	composer = vkms_plane_state->composer;
	memcpy(&composer->src, &new_state->src, sizeof(struct drm_rect));
	memcpy(&composer->dst, &new_state->dst, sizeof(struct drm_rect));
	memcpy(&composer->fb, fb, sizeof(struct drm_framebuffer));
	memcpy(&composer->map, &shadow_plane_state->data, sizeof(composer->map));
	drm_framebuffer_get(&composer->fb);
	composer->offset = fb->offsets[0];
	composer->pitch = fb->pitches[0];
	composer->cpp = fb->format->cpp[0];
	frame_info = vkms_plane_state->frame_info;
	memcpy(&frame_info->src, &new_state->src, sizeof(struct drm_rect));
	memcpy(&frame_info->dst, &new_state->dst, sizeof(struct drm_rect));
	memcpy(&frame_info->fb, fb, sizeof(struct drm_framebuffer));
	memcpy(&frame_info->map, &shadow_plane_state->data, sizeof(frame_info->map));
	drm_framebuffer_get(&frame_info->fb);
	frame_info->offset = fb->offsets[0];
	frame_info->pitch = fb->pitches[0];
	frame_info->cpp = fb->format->cpp[0];
}

static int vkms_plane_atomic_check(struct drm_plane *plane,
-- 
2.30.2

[PATCH v5 4/9] drm: drm_atomic_helper: Add a new helper to deal with the writeback connector validation Export this patch

Add a helper function to validate the connector configuration receive in
the encoder atomic_check by the drivers.

So the drivers don't need do these common validations themselves.
V2: Move the format verification to a new helper at the drm_atomic_helper.c
    (Thomas Zimmermann).
V3: Format check improvements (Leandro Ribeiro).
    Minor improvements(Thomas Zimmermann).

Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 drivers/gpu/drm/drm_atomic_helper.c   | 39 +++++++++++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_writeback.c |  9 +++----
 include/drm/drm_atomic_helper.h       |  3 +++
 3 files changed, 46 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/drm_atomic_helper.c b/drivers/gpu/drm/drm_atomic_helper.c
index 9603193d2fa1..2052e18fa64c 100644
--- a/drivers/gpu/drm/drm_atomic_helper.c
+++ b/drivers/gpu/drm/drm_atomic_helper.c
@@ -776,6 +776,45 @@ drm_atomic_helper_check_modeset(struct drm_device *dev,
}
EXPORT_SYMBOL(drm_atomic_helper_check_modeset);

/**
 * drm_atomic_helper_check_wb_connector_state() - Check writeback encoder state
 * @encoder: encoder state to check
 * @conn_state: connector state to check
 *
 * Checks if the writeback connector state is valid, and returns an error if it
 * isn't.
 *
 * RETURNS:
 * Zero for success or -errno
 */
int
drm_atomic_helper_check_wb_encoder_state(struct drm_encoder *encoder,
					 struct drm_connector_state *conn_state)
{
	struct drm_writeback_job *wb_job = conn_state->writeback_job;
	struct drm_property_blob *pixel_format_blob;
	struct drm_framebuffer *fb;
	size_t i, nformats;
	u32 *formats;

	if (!wb_job || !wb_job->fb)
		return 0;

	pixel_format_blob = wb_job->connector->pixel_formats_blob_ptr;
	nformats = pixel_format_blob->length / sizeof(u32);
	formats = pixel_format_blob->data;
	fb = wb_job->fb;

	for (i = 0; i < nformats; i++)
		if (fb->format->format == formats[i])
			return 0;

	drm_dbg_kms(encoder->dev, "Invalid pixel format %p4cc\n", &fb->format->format);

	return -EINVAL;
}
EXPORT_SYMBOL(drm_atomic_helper_check_wb_encoder_state);

/**
 * drm_atomic_helper_check_plane_state() - Check plane state for validity
 * @plane_state: plane state to check
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index 8694227f555f..746cb0abc6ec 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -30,6 +30,7 @@ static int vkms_wb_encoder_atomic_check(struct drm_encoder *encoder,
{
	struct drm_framebuffer *fb;
	const struct drm_display_mode *mode = &crtc_state->mode;
	int ret;

	if (!conn_state->writeback_job || !conn_state->writeback_job->fb)
		return 0;
@@ -41,11 +42,9 @@ static int vkms_wb_encoder_atomic_check(struct drm_encoder *encoder,
		return -EINVAL;
	}

	if (fb->format->format != vkms_wb_formats[0]) {
		DRM_DEBUG_KMS("Invalid pixel format %p4cc\n",
			      &fb->format->format);
		return -EINVAL;
	}
	ret = drm_atomic_helper_check_wb_encoder_state(encoder, conn_state);
	if (ret < 0)
		return ret;

	return 0;
}
diff --git a/include/drm/drm_atomic_helper.h b/include/drm/drm_atomic_helper.h
index 4045e2507e11..3fbf695da60f 100644
--- a/include/drm/drm_atomic_helper.h
+++ b/include/drm/drm_atomic_helper.h
@@ -40,6 +40,9 @@ struct drm_private_state;

int drm_atomic_helper_check_modeset(struct drm_device *dev,
				struct drm_atomic_state *state);
int
drm_atomic_helper_check_wb_encoder_state(struct drm_encoder *encoder,
					 struct drm_connector_state *conn_state);
int drm_atomic_helper_check_plane_state(struct drm_plane_state *plane_state,
					const struct drm_crtc_state *crtc_state,
					int min_scale,
-- 
2.30.2
Às 17:45 de 04/04/22, Igor Torrente escreveu:

[PATCH v5 5/9] drm: vkms: Add fb information to `vkms_writeback_job` Export this patch

This commit is the groundwork to introduce new formats to the planes and
writeback buffer. As part of it, a new buffer metadata field is added to
`vkms_writeback_job`, this metadata is represented by the `vkms_composer`
struct.
Also adds two new function pointers (`{wb,plane}_format_transform_func`)
are defined to handle format conversion to/from internal format.

These things will allow us, in the future, to have different compositing
and wb format types.

V2: Change the code to get the drm_framebuffer reference and not copy its
    contents(Thomas Zimmermann).
V3: Drop the refcount in the wb code(Thomas Zimmermann).
V5: Add {wb,plane}_format_transform_func to vkms_writeback_job
    and vkms_plane_state (Pekka Paalanen)

Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_composer.c  |  4 ++--
 drivers/gpu/drm/vkms/vkms_drv.h       | 31 +++++++++++++++++++++------
 drivers/gpu/drm/vkms/vkms_plane.c     | 10 ++++-----
 drivers/gpu/drm/vkms/vkms_writeback.c | 20 ++++++++++++++---
 4 files changed, 49 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 2d946368a561..95029d2ebcac 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -153,7 +153,7 @@ static void compose_plane(struct vkms_frame_info *primary_plane_info,
			  struct vkms_frame_info *plane_frame_info,
			  void *vaddr_out)
{
	struct drm_framebuffer *fb = &plane_frame_info->fb;
	struct drm_framebuffer *fb = plane_frame_info->fb;
	void *vaddr;
	void (*pixel_blend)(const u8 *p_src, u8 *p_dst);

@@ -175,7 +175,7 @@ static int compose_active_planes(void **vaddr_out,
				 struct vkms_frame_info *primary_plane_info,
				 struct vkms_crtc_state *crtc_state)
{
	struct drm_framebuffer *fb = &primary_plane_info->fb;
	struct drm_framebuffer *fb = primary_plane_info->fb;
	struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0);
	const void *vaddr;
	int i;
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index 2e6342164bef..2704cfb6904b 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -22,13 +22,8 @@

#define NUM_OVERLAY_PLANES 8

struct vkms_writeback_job {
	struct dma_buf_map map[DRM_FORMAT_MAX_PLANES];
	struct dma_buf_map data[DRM_FORMAT_MAX_PLANES];
};

struct vkms_frame_info {
	struct drm_framebuffer fb;
	struct drm_framebuffer *fb;
	struct drm_rect src, dst;
	struct dma_buf_map map[DRM_FORMAT_MAX_PLANES];
	unsigned int offset;
@@ -36,6 +31,29 @@ struct vkms_frame_info {
	unsigned int cpp;
};

struct pixel_argb_u16 {
	u16 a, r, g, b;
};

struct line_buffer {
	size_t n_pixels;
	struct pixel_argb_u16 *pixels;
};

typedef void
(*wb_format_transform_func)(struct vkms_frame_info *frame_info,
			    const struct line_buffer *buffer, int y);

typedef void
(*plane_format_transform_func)(struct line_buffer *buffer,
			       const struct vkms_frame_info *frame_info, int y);

struct vkms_writeback_job {
	struct dma_buf_map data[DRM_FORMAT_MAX_PLANES];
	struct vkms_frame_info frame_info;
	wb_format_transform_func format_func;
};

/**
 * vkms_plane_state - Driver specific plane state
 * @base: base plane state
@@ -44,6 +62,7 @@ struct vkms_frame_info {
struct vkms_plane_state {
	struct drm_shadow_plane_state base;
	struct vkms_frame_info *frame_info;
	plane_format_transform_func format_func;
};

struct vkms_plane {
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index a56b0f76eddd..28752af0118c 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -50,12 +50,12 @@ static void vkms_plane_destroy_state(struct drm_plane *plane,
	struct vkms_plane_state *vkms_state = to_vkms_plane_state(old_state);
	struct drm_crtc *crtc = vkms_state->base.base.crtc;

	if (crtc) {
	if (crtc && vkms_state->frame_info->fb) {
		/* dropping the reference we acquired in
		 * vkms_primary_plane_update()
		 */
		if (drm_framebuffer_read_refcount(&vkms_state->frame_info->fb))
			drm_framebuffer_put(&vkms_state->frame_info->fb);
		if (drm_framebuffer_read_refcount(vkms_state->frame_info->fb))
			drm_framebuffer_put(vkms_state->frame_info->fb);
	}

	kfree(vkms_state->frame_info);
@@ -110,9 +110,9 @@ static void vkms_plane_atomic_update(struct drm_plane *plane,
	frame_info = vkms_plane_state->frame_info;
	memcpy(&frame_info->src, &new_state->src, sizeof(struct drm_rect));
	memcpy(&frame_info->dst, &new_state->dst, sizeof(struct drm_rect));
	memcpy(&frame_info->fb, fb, sizeof(struct drm_framebuffer));
	frame_info->fb = fb;
	memcpy(&frame_info->map, &shadow_plane_state->data, sizeof(frame_info->map));
	drm_framebuffer_get(&frame_info->fb);
	drm_framebuffer_get(frame_info->fb);
	frame_info->offset = fb->offsets[0];
	frame_info->pitch = fb->pitches[0];
	frame_info->cpp = fb->format->cpp[0];
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index 746cb0abc6ec..ad4bb1fb37ca 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -74,12 +74,15 @@ static int vkms_wb_prepare_job(struct drm_writeback_connector *wb_connector,
	if (!vkmsjob)
		return -ENOMEM;

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

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

	job->priv = vkmsjob;

	return 0;
@@ -98,7 +101,9 @@ static void vkms_wb_cleanup_job(struct drm_writeback_connector *connector,
	if (!job->fb)
		return;

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

	drm_framebuffer_put(vkmsjob->frame_info.fb);

	vkmsdev = drm_device_to_vkms_device(job->fb->dev);
	vkms_set_composer(&vkmsdev->output, false);
@@ -115,14 +120,23 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn,
	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;
	struct vkms_writeback_job *active_wb;
	struct vkms_frame_info *wb_frame_info;

	if (!conn_state)
		return;

	vkms_set_composer(&vkmsdev->output, true);

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

	spin_lock_irq(&output->composer_lock);
	crtc_state->active_writeback = conn_state->writeback_job->priv;
	crtc_state->active_writeback = active_wb;
	wb_frame_info->offset = fb->offsets[0];
	wb_frame_info->pitch = fb->pitches[0];
	wb_frame_info->cpp = fb->format->cpp[0];
	crtc_state->wb_pending = true;
	spin_unlock_irq(&output->composer_lock);
	drm_writeback_queue_job(wb_conn, connector_state);
-- 
2.30.2

[PATCH v5 6/9] drm: vkms: Refactor the plane composer to accept new formats Export this patch

Currently the blend function only accepts XRGB_8888 and ARGB_8888
as a color input.

This patch refactors all the functions related to the plane composition
to overcome this limitation.

A new internal format(`struct pixel`) is introduced to deal with all
possible inputs. It consists of 16 bits fields that represent each of
the channels.

The pixels blend is done using this internal format. And new handlers
are being added to convert a specific format to/from this internal format.

So the blend operation depends on these handlers to convert to this common
format. The blended result, if necessary, is converted to the writeback
buffer format.

This patch introduces three major differences to the blend function.
1 - All the planes are blended at once.
2 - The blend calculus is done as per line instead of per pixel.
3 - It is responsible to calculates the CRC and writing the writeback
buffer(if necessary).

These changes allow us to allocate way less memory in the intermediate
buffer to compute these operations. Because now we don't need to
have the entire intermediate image lines at once, just one line is
enough.

| Memory consumption (output dimensions) |
|:--------------------------------------:|
|       Current      |     This patch    |
|:------------------:|:-----------------:|
|   Width * Heigth   |     2 * Width     |

Beyond memory, we also have a minor performance benefit from all
these changes. Results running the IGT[1] test
`igt@kms_cursor_crc@pipe-a-cursor-512x512-onscreen` ten times:

|                 Frametime                  |
|:------------------------------------------:|
|  Implementation |  Current  |  This commit |
|:---------------:|:---------:|:------------:|
| frametime range |  9~22 ms  |    5~17 ms   |
|     Average     |  11.4 ms  |    7.8 ms    |

[1] IGT commit id: bc3f6833a12221a46659535dac06ebb312490eb4

V2: Improves the performance drastically, by performing the operations
    per-line and not per-pixel(Pekka Paalanen).
    Minor improvements(Pekka Paalanen).
V3: Changes the code to blend the planes all at once. This improves
    performance, memory consumption, and removes much of the weirdness
    of the V2(Pekka Paalanen and me).
    Minor improvements(Pekka Paalanen and me).
V4: Rebase the code and adapt it to the new NUM_OVERLAY_PLANES constant.
V5: Minor checkpatch fixes and the removal of TO-DO item(Melissa Wen).
    Several security/robustness improvents(Pekka Paalanen).
    Removes check_planes_x_bounds function and allows partial
    partly off-screen(Pekka Paalanen).

Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 Documentation/gpu/vkms.rst            |   4 -
 drivers/gpu/drm/vkms/Makefile         |   1 +
 drivers/gpu/drm/vkms/vkms_composer.c  | 318 ++++++++++++--------------
 drivers/gpu/drm/vkms/vkms_formats.c   | 151 ++++++++++++
 drivers/gpu/drm/vkms/vkms_formats.h   |  12 +
 drivers/gpu/drm/vkms/vkms_plane.c     |   3 +
 drivers/gpu/drm/vkms/vkms_writeback.c |   3 +
 7 files changed, 311 insertions(+), 181 deletions(-)
 create mode 100644 drivers/gpu/drm/vkms/vkms_formats.c
 create mode 100644 drivers/gpu/drm/vkms/vkms_formats.h

diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
index 973e2d43108b..a49e4ae92653 100644
--- a/Documentation/gpu/vkms.rst
+++ b/Documentation/gpu/vkms.rst
@@ -118,10 +118,6 @@ Add Plane Features

There's lots of plane features we could add support for:

- Clearing primary plane: clear primary plane before plane composition (at the
  start) for correctness of pixel blend ops. It also guarantees alpha channel
  is cleared in the target buffer for stable crc. [Good to get started]

- ARGB format on primary plane: blend the primary plane into background with
  translucent alpha.

diff --git a/drivers/gpu/drm/vkms/Makefile b/drivers/gpu/drm/vkms/Makefile
index 72f779cbfedd..1b28a6a32948 100644
--- a/drivers/gpu/drm/vkms/Makefile
+++ b/drivers/gpu/drm/vkms/Makefile
@@ -3,6 +3,7 @@ vkms-y := \
	vkms_drv.o \
	vkms_plane.o \
	vkms_output.o \
	vkms_formats.o \
	vkms_crtc.o \
	vkms_composer.o \
	vkms_writeback.o
diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index 95029d2ebcac..cf24015bf90f 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -7,204 +7,186 @@
#include <drm/drm_fourcc.h>
#include <drm/drm_gem_framebuffer_helper.h>
#include <drm/drm_vblank.h>
#include <linux/minmax.h>

#include "vkms_drv.h"

static u32 get_pixel_from_buffer(int x, int y, const u8 *buffer,
				 const struct vkms_frame_info *frame_info)
static u16 pre_mul_blend_channel(u16 src, u16 dst, u16 alpha)
{
	u32 pixel;
	int src_offset = frame_info->offset + (y * frame_info->pitch)
					    + (x * frame_info->cpp);
	u32 new_color;

	pixel = *(u32 *)&buffer[src_offset];
	new_color = (src * 0xffff + dst * (0xffff - alpha));

	return pixel;
	return DIV_ROUND_CLOSEST(new_color, 0xffff);
}

/**
 * compute_crc - Compute CRC value on output frame
 * pre_mul_alpha_blend - alpha blending equation
 * @src_frame_info: source framebuffer's metadata
 * @stage_buffer: The line with the pixels from src_plane
 * @output_buffer: A line buffer that receives all the blends output
 *
 * @vaddr: address to final framebuffer
 * @frame_info: framebuffer's metadata
 * Using the information from the `frame_info`, this blends only the
 * necessary pixels from the `stage_buffer` to the `output_buffer`
 * using premultiplied blend formula.
 *
 * returns CRC value computed using crc32 on the visible portion of
 * the final framebuffer at vaddr_out
 * The current DRM assumption is that pixel color values have been already
 * pre-multiplied with the alpha channel values. See more
 * drm_plane_create_blend_mode_property(). Also, this formula assumes a
 * completely opaque background.
 */
static uint32_t compute_crc(const u8 *vaddr,
			    const struct vkms_frame_info *frame_info)
static void pre_mul_alpha_blend(struct vkms_frame_info *frame_info,
				struct line_buffer *stage_buffer,
				struct line_buffer *output_buffer)
{
	int x, y;
	u32 crc = 0, pixel = 0;
	int x_src = frame_info->src.x1 >> 16;
	int y_src = frame_info->src.y1 >> 16;
	int h_src = drm_rect_height(&frame_info->src) >> 16;
	int w_src = drm_rect_width(&frame_info->src) >> 16;

	for (y = y_src; y < y_src + h_src; ++y) {
		for (x = x_src; x < x_src + w_src; ++x) {
			pixel = get_pixel_from_buffer(x, y, vaddr, frame_info);
			crc = crc32_le(crc, (void *)&pixel, sizeof(u32));
		}
	int x, x_dst = frame_info->dst.x1;
	struct pixel_argb_u16 *out = output_buffer->pixels + x_dst;
	struct pixel_argb_u16 *in = stage_buffer->pixels;
	int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			    stage_buffer->n_pixels);

	for (x = 0; x < x_limit; x++) {
		out[x].a = (u16)0xffff;
		out[x].r = pre_mul_blend_channel(in[x].r, out[x].r, in[x].a);
		out[x].g = pre_mul_blend_channel(in[x].g, out[x].g, in[x].a);
		out[x].b = pre_mul_blend_channel(in[x].b, out[x].b, in[x].a);
	}

	return crc;
}

static u8 blend_channel(u8 src, u8 dst, u8 alpha)
static bool check_y_limit(struct vkms_frame_info *frame_info, int y)
{
	u32 pre_blend;
	u8 new_color;

	pre_blend = (src * 255 + dst * (255 - alpha));

	/* Faster div by 255 */
	new_color = ((pre_blend + ((pre_blend + 257) >> 8)) >> 8);
	if (y >= frame_info->dst.y1 && y < frame_info->dst.y2)
		return true;

	return new_color;
	return false;
}

/**
 * alpha_blend - alpha blending equation
 * @argb_src: src pixel on premultiplied alpha mode
 * @argb_dst: dst pixel completely opaque
 * @wb_frame_info: The writeback frame buffer metadata
 * @crtc_state: The crtc state
 * @crc32: The crc output of the final frame
 * @output_buffer: A buffer of a row that will receive the result of the blend(s)
 * @stage_buffer: The line with the pixels from plane being blend to the output
 *
 * blend pixels using premultiplied blend formula. The current DRM assumption
 * is that pixel color values have been already pre-multiplied with the alpha
 * channel values. See more drm_plane_create_blend_mode_property(). Also, this
 * formula assumes a completely opaque background.
 * This function blends the pixels (Using the `pre_mul_alpha_blend`)
 * from all planes, calculates the crc32 of the output from the former step,
 * and, if necessary, convert and store the output to the writeback buffer.
 */
static void alpha_blend(const u8 *argb_src, u8 *argb_dst)
static void blend(struct vkms_writeback_job *wb,
		  struct vkms_crtc_state *crtc_state,
		  u32 *crc32, struct line_buffer *stage_buffer,
		  struct line_buffer *output_buffer, s64 row_size)
{
	u8 alpha;
	struct vkms_plane_state **plane = crtc_state->active_planes;
	struct vkms_frame_info *primary_plane_info = plane[0]->frame_info;
	u32 n_active_planes = crtc_state->num_active_planes;

	int y_dst = primary_plane_info->dst.y1;
	int h_dst = drm_rect_height(&primary_plane_info->dst);
	int y_limit = y_dst + h_dst;
	int y, i;

	for (y = y_dst; y < y_limit; y++) {
		plane[0]->format_func(output_buffer, primary_plane_info, y);

		/* If there are other planes besides primary, we consider the active
		 * planes should be in z-order and compose them associatively:
		 * ((primary <- overlay) <- cursor)
		 */
		for (i = 1; i < n_active_planes; i++) {
			if (!check_y_limit(plane[i]->frame_info, y))
				continue;

			plane[i]->format_func(stage_buffer, plane[i]->frame_info, y);
			pre_mul_alpha_blend(plane[i]->frame_info, stage_buffer,
					    output_buffer);
		}

	alpha = argb_src[3];
	argb_dst[0] = blend_channel(argb_src[0], argb_dst[0], alpha);
	argb_dst[1] = blend_channel(argb_src[1], argb_dst[1], alpha);
	argb_dst[2] = blend_channel(argb_src[2], argb_dst[2], alpha);
}
		*crc32 = crc32_le(*crc32, (void *)output_buffer->pixels, row_size);

/**
 * x_blend - blending equation that ignores the pixel alpha
 *
 * overwrites RGB color value from src pixel to dst pixel.
 */
static void x_blend(const u8 *xrgb_src, u8 *xrgb_dst)
{
	memcpy(xrgb_dst, xrgb_src, sizeof(u8) * 3);
}

/**
 * blend - blend value at vaddr_src with value at vaddr_dst
 * @vaddr_dst: destination address
 * @vaddr_src: source address
 * @dst_frame_info: destination framebuffer's metadata
 * @src_frame_info: source framebuffer's metadata
 * @pixel_blend: blending equation based on plane format
 *
 * Blend the vaddr_src value with the vaddr_dst value using a pixel blend
 * equation according to the supported plane formats DRM_FORMAT_(A/XRGB8888)
 * and clearing alpha channel to an completely opaque background. This function
 * uses buffer's metadata to locate the new composite values at vaddr_dst.
 *
 * TODO: completely clear the primary plane (a = 0xff) before starting to blend
 * pixel color values
 */
static void blend(void *vaddr_dst, void *vaddr_src,
		  struct vkms_frame_info *dst_frame_info,
		  struct vkms_frame_info *src_frame_info,
		  void (*pixel_blend)(const u8 *, u8 *))
{
	int i, j, j_dst, i_dst;
	int offset_src, offset_dst;
	u8 *pixel_dst, *pixel_src;

	int x_src = src_frame_info->src.x1 >> 16;
	int y_src = src_frame_info->src.y1 >> 16;

	int x_dst = src_frame_info->dst.x1;
	int y_dst = src_frame_info->dst.y1;
	int h_dst = drm_rect_height(&src_frame_info->dst);
	int w_dst = drm_rect_width(&src_frame_info->dst);

	int y_limit = y_src + h_dst;
	int x_limit = x_src + w_dst;

	for (i = y_src, i_dst = y_dst; i < y_limit; ++i) {
		for (j = x_src, j_dst = x_dst; j < x_limit; ++j) {
			offset_dst = dst_frame_info->offset
				     + (i_dst * dst_frame_info->pitch)
				     + (j_dst++ * dst_frame_info->cpp);
			offset_src = src_frame_info->offset
				     + (i * src_frame_info->pitch)
				     + (j * src_frame_info->cpp);

			pixel_src = (u8 *)(vaddr_src + offset_src);
			pixel_dst = (u8 *)(vaddr_dst + offset_dst);
			pixel_blend(pixel_src, pixel_dst);
			/* clearing alpha channel (0xff)*/
			pixel_dst[3] = 0xff;
		}
		i_dst++;
		if (wb)
			wb->format_func(&wb->frame_info, output_buffer, y);
	}
}

static void compose_plane(struct vkms_frame_info *primary_plane_info,
			  struct vkms_frame_info *plane_frame_info,
			  void *vaddr_out)
static int check_format_funcs(struct vkms_crtc_state *crtc_state,
			      struct vkms_writeback_job *active_wb)
{
	struct drm_framebuffer *fb = plane_frame_info->fb;
	void *vaddr;
	void (*pixel_blend)(const u8 *p_src, u8 *p_dst);

	if (WARN_ON(dma_buf_map_is_null(&primary_plane_info->map[0])))
		return;
	struct vkms_plane_state **planes = crtc_state->active_planes;
	u32 n_active_planes = crtc_state->num_active_planes;
	int i;

	vaddr = plane_frame_info->map[0].vaddr;
	for (i = 0; i < n_active_planes; i++)
		if (!planes[i]->format_func)
			return -1;

	if (fb->format->format == DRM_FORMAT_ARGB8888)
		pixel_blend = &alpha_blend;
	else
		pixel_blend = &x_blend;
	if (active_wb && !active_wb->format_func)
		return -1;

	blend(vaddr_out, vaddr, primary_plane_info,
	      plane_frame_info, pixel_blend);
	return 0;
}

static int compose_active_planes(void **vaddr_out,
				 struct vkms_frame_info *primary_plane_info,
				 struct vkms_crtc_state *crtc_state)
static int compose_active_planes(struct vkms_writeback_job *active_wb,
				 struct vkms_crtc_state *crtc_state,
				 u32 *crc32)
{
	struct drm_framebuffer *fb = primary_plane_info->fb;
	struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0);
	const void *vaddr;
	int i;
	int line_width, ret = 0, pixel_size = sizeof(struct pixel_argb_u16);
	struct vkms_frame_info *primary_plane_info = NULL;
	struct line_buffer output_buffer, stage_buffer;
	struct vkms_plane_state *act_plane = NULL;
	u32 wb_format;

	if (!*vaddr_out) {
		*vaddr_out = kvzalloc(gem_obj->size, GFP_KERNEL);
		if (!*vaddr_out) {
			DRM_ERROR("Cannot allocate memory for output frame.");
			return -ENOMEM;
		}
	if (WARN_ON(pixel_size != 8))
		return -EINVAL;

	if (crtc_state->num_active_planes >= 1) {
		act_plane = crtc_state->active_planes[0];
		if (act_plane->base.base.plane->type == DRM_PLANE_TYPE_PRIMARY)
			primary_plane_info = act_plane->frame_info;
	}

	if (!primary_plane_info)
		return -EINVAL;

	if (WARN_ON(dma_buf_map_is_null(&primary_plane_info->map[0])))
		return -EINVAL;

	vaddr = primary_plane_info->map[0].vaddr;
	if (WARN_ON(check_format_funcs(crtc_state, active_wb)))
		return -EINVAL;

	memcpy(*vaddr_out, vaddr, gem_obj->size);
	line_width = drm_rect_width(&primary_plane_info->dst);
	stage_buffer.n_pixels = line_width;
	output_buffer.n_pixels = line_width;

	/* If there are other planes besides primary, we consider the active
	 * planes should be in z-order and compose them associatively:
	 * ((primary <- overlay) <- cursor)
	 */
	for (i = 1; i < crtc_state->num_active_planes; i++)
		compose_plane(primary_plane_info,
			      crtc_state->active_planes[i]->frame_info,
			      *vaddr_out);
	stage_buffer.pixels = kvmalloc(line_width * pixel_size, GFP_KERNEL);
	if (!stage_buffer.pixels) {
		DRM_ERROR("Cannot allocate memory for the output line buffer");
		return -ENOMEM;
	}

	return 0;
	output_buffer.pixels = kvmalloc(line_width * pixel_size, GFP_KERNEL);
	if (!output_buffer.pixels) {
		DRM_ERROR("Cannot allocate memory for intermediate line buffer");
		ret = -ENOMEM;
		goto free_stage_buffer;
	}

	if (active_wb) {
		struct vkms_frame_info *wb_frame_info = &active_wb->frame_info;

		wb_format = wb_frame_info->fb->format->format;
		wb_frame_info->src = primary_plane_info->src;
		wb_frame_info->dst = primary_plane_info->dst;
	}

	blend(active_wb, crtc_state, crc32, &stage_buffer,
	      &output_buffer, (s64)line_width * pixel_size);

	kvfree(output_buffer.pixels);
free_stage_buffer:
	kvfree(stage_buffer.pixels);

	return ret;
}

/**
@@ -222,13 +204,11 @@ void vkms_composer_worker(struct work_struct *work)
						struct vkms_crtc_state,
						composer_work);
	struct drm_crtc *crtc = crtc_state->base.crtc;
	struct vkms_writeback_job *active_wb = crtc_state->active_writeback;
	struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
	struct vkms_frame_info *primary_plane_info = NULL;
	struct vkms_plane_state *act_plane = NULL;
	bool crc_pending, wb_pending;
	void *vaddr_out = NULL;
	u32 crc32 = 0;
	u64 frame_start, frame_end;
	u32 crc32 = 0;
	int ret;

	spin_lock_irq(&out->composer_lock);
@@ -248,35 +228,19 @@ void vkms_composer_worker(struct work_struct *work)
	if (!crc_pending)
		return;

	if (crtc_state->num_active_planes >= 1) {
		act_plane = crtc_state->active_planes[0];
		if (act_plane->base.base.plane->type == DRM_PLANE_TYPE_PRIMARY)
			primary_plane_info = act_plane->frame_info;
	}

	if (!primary_plane_info)
		return;

	if (wb_pending)
		vaddr_out = crtc_state->active_writeback->data[0].vaddr;
		ret = compose_active_planes(active_wb, crtc_state, &crc32);
	else
		ret = compose_active_planes(NULL, crtc_state, &crc32);

	ret = compose_active_planes(&vaddr_out, primary_plane_info,
				    crtc_state);
	if (ret) {
		if (ret == -EINVAL && !wb_pending)
			kvfree(vaddr_out);
	if (ret)
		return;
	}

	crc32 = compute_crc(vaddr_out, primary_plane_info);

	if (wb_pending) {
		drm_writeback_signal_completion(&out->wb_connector, 0);
		spin_lock_irq(&out->composer_lock);
		crtc_state->wb_pending = false;
		spin_unlock_irq(&out->composer_lock);
	} else {
		kvfree(vaddr_out);
	}

	/*
diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
new file mode 100644
index 000000000000..931a61405d6a
--- /dev/null
+++ b/drivers/gpu/drm/vkms/vkms_formats.c
@@ -0,0 +1,151 @@
// SPDX-License-Identifier: GPL-2.0+

#include <drm/drm_rect.h>
#include <linux/minmax.h>

#include "vkms_formats.h"

static int pixel_offset(const struct vkms_frame_info *frame_info, int x, int y)
{
	return frame_info->offset + (y * frame_info->pitch)
				  + (x * frame_info->cpp);
}

/*
 * packed_pixels_addr - Get the pointer to pixel of a given pair of coordinates
 *
 * @frame_info: Buffer metadata
 * @x: The x(width) coordinate of the 2D buffer
 * @y: The y(Heigth) coordinate of the 2D buffer
 *
 * Takes the information stored in the frame_info, a pair of coordinates, and
 * returns the address of the first color channel.
 * This function assumes the channels are packed together, i.e. a color channel
 * comes immediately after another in the memory. And therefore, this function
 * doesn't work for YUV with chroma subsampling (e.g. YUV420 and NV21).
 */
static void *packed_pixels_addr(const struct vkms_frame_info *frame_info,
				int x, int y)
{
	int offset = pixel_offset(frame_info, x, y);

	return (u8 *)frame_info->map[0].vaddr + offset;
}

static void *get_packed_src_addr(const struct vkms_frame_info *frame_info, int y)
{
	int x_src = frame_info->src.x1 >> 16;
	int y_src = y - frame_info->dst.y1 + (frame_info->src.y1 >> 16);

	return packed_pixels_addr(frame_info, x_src, y_src);
}

static void ARGB8888_to_argb_u16(struct line_buffer *stage_buffer,
				 const struct vkms_frame_info *frame_info, int y)
{
	struct pixel_argb_u16 *out_pixels = stage_buffer->pixels;
	u8 *src_pixels = get_packed_src_addr(frame_info, y);
	int x, x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			       stage_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, src_pixels += 4) {
		/*
		 * The 257 is the "conversion ratio". This number is obtained by the
		 * (2^16 - 1) / (2^8 - 1) division. Which, in this case, tries to get
		 * the best color value in a pixel format with more possibilities.
		 * A similar idea applies to others RGB color conversions.
		 */
		out_pixels[x].a = (u16)src_pixels[3] * 257;
		out_pixels[x].r = (u16)src_pixels[2] * 257;
		out_pixels[x].g = (u16)src_pixels[1] * 257;
		out_pixels[x].b = (u16)src_pixels[0] * 257;
	}
}

static void XRGB8888_to_argb_u16(struct line_buffer *stage_buffer,
				 const struct vkms_frame_info *frame_info, int y)
{
	struct pixel_argb_u16 *out_pixels = stage_buffer->pixels;
	u8 *src_pixels = get_packed_src_addr(frame_info, y);
	int x, x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			       stage_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, src_pixels += 4) {
		out_pixels[x].a = (u16)0xffff;
		out_pixels[x].r = (u16)src_pixels[2] * 257;
		out_pixels[x].g = (u16)src_pixels[1] * 257;
		out_pixels[x].b = (u16)src_pixels[0] * 257;
	}
}

/*
 * The following  functions take an line of argb_u16 pixels from the
 * src_buffer, convert them to a specific format, and store them in the
 * destination.
 *
 * They are used in the `compose_active_planes` to convert and store a line
 * from the src_buffer to the writeback buffer.
 */
static void argb_u16_to_ARGB8888(struct vkms_frame_info *frame_info,
				 const struct line_buffer *src_buffer, int y)
{
	int x, x_dst = frame_info->dst.x1;
	u8 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y);
	struct pixel_argb_u16 *in_pixels = src_buffer->pixels;
	int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			    src_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, dst_pixels += 4) {
		/*
		 * This sequence below is important because the format's byte order is
		 * in little-endian. In the case of the ARGB8888 the memory is
		 * organized this way:
		 *
		 * | Addr     | = blue channel
		 * | Addr + 1 | = green channel
		 * | Addr + 2 | = Red channel
		 * | Addr + 3 | = Alpha channel
		 */
		dst_pixels[3] = DIV_ROUND_CLOSEST(in_pixels[x].a, 257);
		dst_pixels[2] = DIV_ROUND_CLOSEST(in_pixels[x].r, 257);
		dst_pixels[1] = DIV_ROUND_CLOSEST(in_pixels[x].g, 257);
		dst_pixels[0] = DIV_ROUND_CLOSEST(in_pixels[x].b, 257);
	}
}

static void argb_u16_to_XRGB8888(struct vkms_frame_info *frame_info,
				 const struct line_buffer *src_buffer, int y)
{
	int x, x_dst = frame_info->dst.x1;
	u8 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y);
	struct pixel_argb_u16 *in_pixels = src_buffer->pixels;
	int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			    src_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, dst_pixels += 4) {
		dst_pixels[3] = (u8)0xff;
		dst_pixels[2] = DIV_ROUND_CLOSEST(in_pixels[x].r, 257);
		dst_pixels[1] = DIV_ROUND_CLOSEST(in_pixels[x].g, 257);
		dst_pixels[0] = DIV_ROUND_CLOSEST(in_pixels[x].b, 257);
	}
}

plane_format_transform_func get_plane_fmt_transform_function(u32 format)
{
	if (format == DRM_FORMAT_ARGB8888)
		return &ARGB8888_to_argb_u16;
	else if (format == DRM_FORMAT_XRGB8888)
		return &XRGB8888_to_argb_u16;
	else
		return NULL;
}

wb_format_transform_func get_wb_fmt_transform_function(u32 format)
{
	if (format == DRM_FORMAT_ARGB8888)
		return &argb_u16_to_ARGB8888;
	else if (format == DRM_FORMAT_XRGB8888)
		return &argb_u16_to_XRGB8888;
	else
		return NULL;
}
diff --git a/drivers/gpu/drm/vkms/vkms_formats.h b/drivers/gpu/drm/vkms/vkms_formats.h
new file mode 100644
index 000000000000..adc5a17b9584
--- /dev/null
+++ b/drivers/gpu/drm/vkms/vkms_formats.h
@@ -0,0 +1,12 @@
// SPDX-License-Identifier: GPL-2.0+

#ifndef _VKMS_FORMATS_H_
#define _VKMS_FORMATS_H_

#include "vkms_drv.h"

plane_format_transform_func get_plane_fmt_transform_function(u32 format);

wb_format_transform_func get_wb_fmt_transform_function(u32 format);

#endif /* _VKMS_FORMATS_H_ */
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index 28752af0118c..798243837fd0 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -10,6 +10,7 @@
#include <drm/drm_plane_helper.h>

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

static const u32 vkms_formats[] = {
	DRM_FORMAT_XRGB8888,
@@ -100,6 +101,7 @@ static void vkms_plane_atomic_update(struct drm_plane *plane,
	struct drm_shadow_plane_state *shadow_plane_state;
	struct drm_framebuffer *fb = new_state->fb;
	struct vkms_frame_info *frame_info;
	u32 fmt = fb->format->format;

	if (!new_state->crtc || !fb)
		return;
@@ -116,6 +118,7 @@ static void vkms_plane_atomic_update(struct drm_plane *plane,
	frame_info->offset = fb->offsets[0];
	frame_info->pitch = fb->pitches[0];
	frame_info->cpp = fb->format->cpp[0];
	vkms_plane_state->format_func = get_plane_fmt_transform_function(fmt);
}

static int vkms_plane_atomic_check(struct drm_plane *plane,
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index ad4bb1fb37ca..97f71e784bbf 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -11,6 +11,7 @@
#include <drm/drm_gem_shmem_helper.h>

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

static const u32 vkms_wb_formats[] = {
	DRM_FORMAT_XRGB8888,
@@ -123,6 +124,7 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn,
	struct drm_framebuffer *fb = connector_state->writeback_job->fb;
	struct vkms_writeback_job *active_wb;
	struct vkms_frame_info *wb_frame_info;
	u32 wb_format = fb->format->format;

	if (!conn_state)
		return;
@@ -140,6 +142,7 @@ static void vkms_wb_atomic_commit(struct drm_connector *conn,
	crtc_state->wb_pending = true;
	spin_unlock_irq(&output->composer_lock);
	drm_writeback_queue_job(wb_conn, connector_state);
	active_wb->format_func = get_wb_fmt_transform_function(wb_format);
}

static const struct drm_connector_helper_funcs vkms_wb_conn_helper_funcs = {
-- 
2.30.2

[PATCH v5 7/9] drm: vkms: Supports to the case where primary plane doesn't match the CRTC Export this patch

We will break the current assumption that the primary plane has the
same size and position as CRTC.
For that we will add CRTC dimension information to `vkms_crtc_state`
and add a opaque black backgound color.

Because now we need to fill the background, we had a loss in
performance with this change. Results running the IGT[1] test
`igt@kms_cursor_crc@pipe-a-cursor-512x512-onscreen` ten times:

|                  Frametime                   |
|:--------------------------------------------:|
|  Implementation |  Previous |   This commit  |
|:---------------:|:---------:|:--------------:|
| frametime range |  5~18 ms  |     10~22 ms   |
|     Average     |  8.47 ms  |     12.32 ms   |

[1] IGT commit id: bc3f6833a12221a46659535dac06ebb312490eb4

Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 Documentation/gpu/vkms.rst           |  3 +--
 drivers/gpu/drm/vkms/vkms_composer.c | 32 +++++++++++++++++++---------
 drivers/gpu/drm/vkms/vkms_crtc.c     |  4 ++++
 drivers/gpu/drm/vkms/vkms_drv.h      |  2 ++
 4 files changed, 29 insertions(+), 12 deletions(-)

diff --git a/Documentation/gpu/vkms.rst b/Documentation/gpu/vkms.rst
index a49e4ae92653..49db221c0f52 100644
--- a/Documentation/gpu/vkms.rst
+++ b/Documentation/gpu/vkms.rst
@@ -121,8 +121,7 @@ There's lots of plane features we could add support for:
- ARGB format on primary plane: blend the primary plane into background with
  translucent alpha.

- Support when the primary plane isn't exactly matching the output size: blend
  the primary plane into the black background.
- Add background color KMS property[Good to get started].

- Full alpha blending on all planes.

diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index cf24015bf90f..f80842227669 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -61,6 +61,15 @@ static bool check_y_limit(struct vkms_frame_info *frame_info, int y)
	return false;
}

static void fill_background(struct pixel_argb_u16 *backgroud_color,
			    struct line_buffer *output_buffer)
{
	int i;

	for (i = 0; i < output_buffer->n_pixels; i++)
		output_buffer->pixels[i] = *backgroud_color;
}

/**
 * @wb_frame_info: The writeback frame buffer metadata
 * @crtc_state: The crtc state
@@ -78,22 +87,23 @@ static void blend(struct vkms_writeback_job *wb,
		  struct line_buffer *output_buffer, s64 row_size)
{
	struct vkms_plane_state **plane = crtc_state->active_planes;
	struct vkms_frame_info *primary_plane_info = plane[0]->frame_info;
	u32 n_active_planes = crtc_state->num_active_planes;

	int y_dst = primary_plane_info->dst.y1;
	int h_dst = drm_rect_height(&primary_plane_info->dst);
	int y_limit = y_dst + h_dst;
	struct pixel_argb_u16 background_color = (struct pixel_argb_u16) {
		.a = 0xffff
	};

	int crtc_y_limit = crtc_state->crtc_height;
	int y, i;

	for (y = y_dst; y < y_limit; y++) {
		plane[0]->format_func(output_buffer, primary_plane_info, y);
	for (y = 0; y < crtc_y_limit; y++) {
		fill_background(&background_color, output_buffer);

		/* If there are other planes besides primary, we consider the active
		 * planes should be in z-order and compose them associatively:
		 * ((primary <- overlay) <- cursor)
		 */
		for (i = 1; i < n_active_planes; i++) {
		for (i = 0; i < n_active_planes; i++) {
			if (!check_y_limit(plane[i]->frame_info, y))
				continue;

@@ -154,7 +164,7 @@ static int compose_active_planes(struct vkms_writeback_job *active_wb,
	if (WARN_ON(check_format_funcs(crtc_state, active_wb)))
		return -EINVAL;

	line_width = drm_rect_width(&primary_plane_info->dst);
	line_width = crtc_state->crtc_width;
	stage_buffer.n_pixels = line_width;
	output_buffer.n_pixels = line_width;

@@ -175,8 +185,10 @@ static int compose_active_planes(struct vkms_writeback_job *active_wb,
		struct vkms_frame_info *wb_frame_info = &active_wb->frame_info;

		wb_format = wb_frame_info->fb->format->format;
		wb_frame_info->src = primary_plane_info->src;
		wb_frame_info->dst = primary_plane_info->dst;
		drm_rect_init(&wb_frame_info->src, 0, 0, crtc_state->crtc_width,
			      crtc_state->crtc_height);
		drm_rect_init(&wb_frame_info->dst, 0, 0, crtc_state->crtc_width,
			      crtc_state->crtc_height);
	}

	blend(active_wb, crtc_state, crc32, &stage_buffer,
diff --git a/drivers/gpu/drm/vkms/vkms_crtc.c b/drivers/gpu/drm/vkms/vkms_crtc.c
index 57bbd32e9beb..4a37e243c2d7 100644
--- a/drivers/gpu/drm/vkms/vkms_crtc.c
+++ b/drivers/gpu/drm/vkms/vkms_crtc.c
@@ -248,7 +248,9 @@ static void vkms_crtc_atomic_begin(struct drm_crtc *crtc,
static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
				   struct drm_atomic_state *state)
{
	struct drm_crtc_state *crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
	struct vkms_output *vkms_output = drm_crtc_to_vkms_output(crtc);
	struct drm_display_mode *mode = &crtc_state->mode;

	if (crtc->state->event) {
		spin_lock(&crtc->dev->event_lock);
@@ -264,6 +266,8 @@ static void vkms_crtc_atomic_flush(struct drm_crtc *crtc,
	}

	vkms_output->composer_state = to_vkms_crtc_state(crtc->state);
	vkms_output->composer_state->crtc_width = mode->hdisplay;
	vkms_output->composer_state->crtc_height = mode->vdisplay;

	spin_unlock_irq(&vkms_output->lock);
}
diff --git a/drivers/gpu/drm/vkms/vkms_drv.h b/drivers/gpu/drm/vkms/vkms_drv.h
index 2704cfb6904b..ab92d9f7b701 100644
--- a/drivers/gpu/drm/vkms/vkms_drv.h
+++ b/drivers/gpu/drm/vkms/vkms_drv.h
@@ -90,6 +90,8 @@ struct vkms_crtc_state {
	bool wb_pending;
	u64 frame_start;
	u64 frame_end;
	u16 crtc_width;
	u16 crtc_height;
};

struct vkms_output {
-- 
2.30.2

[PATCH v5 8/9] drm: vkms: Adds XRGB_16161616 and ARGB_1616161616 formats Export this patch

This will be useful to write tests that depends on these formats.

ARGB and XRGB follows the a similar implementation of the former formats.
Just adjusting for 16 bits per channel.

V3: Adapt the handlers to the new format introduced in patch 7 V3.
V5: Minor improvements
    Added le16_to_cpu/cpu_to_le16 to the 16 bits color read/writes.
Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_formats.c   | 77 +++++++++++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_plane.c     |  5 +-
 drivers/gpu/drm/vkms/vkms_writeback.c |  2 +
 3 files changed, 83 insertions(+), 1 deletion(-)
diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
index 931a61405d6a..8d913fa7dbde 100644
--- a/drivers/gpu/drm/vkms/vkms_formats.c
+++ b/drivers/gpu/drm/vkms/vkms_formats.c
@@ -78,6 +78,41 @@ static void XRGB8888_to_argb_u16(struct line_buffer *stage_buffer,
	}
}

static void ARGB16161616_to_argb_u16(struct line_buffer *stage_buffer,
				     const struct vkms_frame_info *frame_info,
				     int y)
{
	struct pixel_argb_u16 *out_pixels = stage_buffer->pixels;
	u16 *src_pixels = get_packed_src_addr(frame_info, y);
	int x, x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			       stage_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, src_pixels += 4) {
		out_pixels[x].a = le16_to_cpu(src_pixels[3]);
		out_pixels[x].r = le16_to_cpu(src_pixels[2]);
		out_pixels[x].g = le16_to_cpu(src_pixels[1]);
		out_pixels[x].b = le16_to_cpu(src_pixels[0]);
	}
}

static void XRGB16161616_to_argb_u16(struct line_buffer *stage_buffer,
				     const struct vkms_frame_info *frame_info,
				     int y)
{
	struct pixel_argb_u16 *out_pixels = stage_buffer->pixels;
	u16 *src_pixels = get_packed_src_addr(frame_info, y);
	int x, x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			       stage_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, src_pixels += 4) {
		out_pixels[x].a = (u16)0xffff;
		out_pixels[x].r = le16_to_cpu(src_pixels[2]);
		out_pixels[x].g = le16_to_cpu(src_pixels[1]);
		out_pixels[x].b = le16_to_cpu(src_pixels[0]);
	}
}


/*
 * The following  functions take an line of argb_u16 pixels from the
 * src_buffer, convert them to a specific format, and store them in the
@@ -130,12 +165,50 @@ static void argb_u16_to_XRGB8888(struct vkms_frame_info *frame_info,
	}
}

static void argb_u16_to_ARGB16161616(struct vkms_frame_info *frame_info,
				     const struct line_buffer *src_buffer, int y)
{
	int x, x_dst = frame_info->dst.x1;
	u16 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y);
	struct pixel_argb_u16 *in_pixels = src_buffer->pixels;
	int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			    src_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, dst_pixels += 4) {
		dst_pixels[3] = cpu_to_le16(in_pixels[x].a);
		dst_pixels[2] = cpu_to_le16(in_pixels[x].r);
		dst_pixels[1] = cpu_to_le16(in_pixels[x].g);
		dst_pixels[0] = cpu_to_le16(in_pixels[x].b);
	}
}

static void argb_u16_to_XRGB16161616(struct vkms_frame_info *frame_info,
				     const struct line_buffer *src_buffer, int y)
{
	int x, x_dst = frame_info->dst.x1;
	u16 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y);
	struct pixel_argb_u16 *in_pixels = src_buffer->pixels;
	int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			    src_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, dst_pixels += 4) {
		dst_pixels[3] = (u8)0xffff;
		dst_pixels[2] = cpu_to_le16(in_pixels[x].r);
		dst_pixels[1] = cpu_to_le16(in_pixels[x].g);
		dst_pixels[0] = cpu_to_le16(in_pixels[x].b);
	}
}

plane_format_transform_func get_plane_fmt_transform_function(u32 format)
{
	if (format == DRM_FORMAT_ARGB8888)
		return &ARGB8888_to_argb_u16;
	else if (format == DRM_FORMAT_XRGB8888)
		return &XRGB8888_to_argb_u16;
	else if (format == DRM_FORMAT_ARGB16161616)
		return &ARGB16161616_to_argb_u16;
	else if (format == DRM_FORMAT_XRGB16161616)
		return &XRGB16161616_to_argb_u16;
	else
		return NULL;
}
@@ -146,6 +219,10 @@ wb_format_transform_func get_wb_fmt_transform_function(u32 format)
		return &argb_u16_to_ARGB8888;
	else if (format == DRM_FORMAT_XRGB8888)
		return &argb_u16_to_XRGB8888;
	else if (format == DRM_FORMAT_ARGB16161616)
		return &argb_u16_to_ARGB16161616;
	else if (format == DRM_FORMAT_XRGB16161616)
		return &argb_u16_to_XRGB16161616;
	else
		return NULL;
}
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index 798243837fd0..60054a85204a 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -14,11 +14,14 @@

static const u32 vkms_formats[] = {
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_XRGB16161616
};

static const u32 vkms_plane_formats[] = {
	DRM_FORMAT_ARGB8888,
	DRM_FORMAT_XRGB8888
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_XRGB16161616,
	DRM_FORMAT_ARGB16161616
};

static struct drm_plane_state *
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index 97f71e784bbf..cb63a5da9af1 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -15,6 +15,8 @@

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

static const struct drm_connector_funcs vkms_wb_connector_funcs = {
-- 
2.30.2
Hi

Am 04.04.22 um 22:45 schrieb Igor Torrente:

[PATCH v5 9/9] drm: vkms: Add support to the RGB565 format Export this patch

Adds this common format to vkms.

This commit also adds new helper macros to deal with fixed-point
arithmetic.

It was done to improve the precision of the conversion to ARGB16161616
since the "conversion ratio" is not an integer.

V3: Adapt the handlers to the new format introduced in patch 7 V3.
V5: Minor improvements

Signed-off-by: Igor Torrente <igormtorrente@gmail.com>
---
 drivers/gpu/drm/vkms/vkms_formats.c   | 70 +++++++++++++++++++++++++++
 drivers/gpu/drm/vkms/vkms_plane.c     |  6 ++-
 drivers/gpu/drm/vkms/vkms_writeback.c |  3 +-
 3 files changed, 76 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_formats.c b/drivers/gpu/drm/vkms/vkms_formats.c
index 8d913fa7dbde..4af8b295f31e 100644
--- a/drivers/gpu/drm/vkms/vkms_formats.c
+++ b/drivers/gpu/drm/vkms/vkms_formats.c
@@ -5,6 +5,23 @@

#include "vkms_formats.h"

/* The following macros help doing fixed point arithmetic. */
/*
 * With Fixed-Point scale 15 we have 17 and 15 bits of integer and fractional
 * parts respectively.
 *  | 0000 0000 0000 0000 0.000 0000 0000 0000 |
 * 31                                          0
 */
#define FIXED_SCALE 15

#define INT_TO_FIXED(a) ((a) << FIXED_SCALE)
#define FIXED_MUL(a, b) ((s32)(((s64)(a) * (b)) >> FIXED_SCALE))
#define FIXED_DIV(a, b) ((s32)(((s64)(a) << FIXED_SCALE) / (b)))
/* This macro converts a fixed point number to int, and round half up it */
#define FIXED_TO_INT_ROUND(a) (((a) + (1 << (FIXED_SCALE - 1))) >> FIXED_SCALE)
/* Convert divisor and dividend to Fixed-Point and performs the division */
#define INT_TO_FIXED_DIV(a, b) (FIXED_DIV(INT_TO_FIXED(a), INT_TO_FIXED(b)))

static int pixel_offset(const struct vkms_frame_info *frame_info, int x, int y)
{
	return frame_info->offset + (y * frame_info->pitch)
@@ -112,6 +129,30 @@ static void XRGB16161616_to_argb_u16(struct line_buffer *stage_buffer,
	}
}

static void RGB565_to_argb_u16(struct line_buffer *stage_buffer,
			       const struct vkms_frame_info *frame_info, int y)
{
	struct pixel_argb_u16 *out_pixels = stage_buffer->pixels;
	u16 *src_pixels = get_packed_src_addr(frame_info, y);
	int x, x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			       stage_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, src_pixels++) {
		u16 rgb_565 = le16_to_cpu(*src_pixels);
		int fp_r = INT_TO_FIXED((rgb_565 >> 11) & 0x1f);
		int fp_g = INT_TO_FIXED((rgb_565 >> 5) & 0x3f);
		int fp_b = INT_TO_FIXED(rgb_565 & 0x1f);

		int fp_rb_ratio = INT_TO_FIXED_DIV(65535, 31);
		int fp_g_ratio = INT_TO_FIXED_DIV(65535, 63);

		out_pixels[x].a = (u16)0xffff;
		out_pixels[x].r = FIXED_TO_INT_ROUND(FIXED_MUL(fp_r, fp_rb_ratio));
		out_pixels[x].g = FIXED_TO_INT_ROUND(FIXED_MUL(fp_g, fp_g_ratio));
		out_pixels[x].b = FIXED_TO_INT_ROUND(FIXED_MUL(fp_b, fp_rb_ratio));
	}
}


/*
 * The following  functions take an line of argb_u16 pixels from the
@@ -199,6 +240,31 @@ static void argb_u16_to_XRGB16161616(struct vkms_frame_info *frame_info,
	}
}

static void argb_u16_to_RGB565(struct vkms_frame_info *frame_info,
			       const struct line_buffer *src_buffer, int y)
{
	int x, x_dst = frame_info->dst.x1;
	u16 *dst_pixels = packed_pixels_addr(frame_info, x_dst, y);
	struct pixel_argb_u16 *in_pixels = src_buffer->pixels;
	int x_limit = min_t(size_t, drm_rect_width(&frame_info->dst),
			    src_buffer->n_pixels);

	for (x = 0; x < x_limit; x++, dst_pixels++) {
		int fp_r = INT_TO_FIXED(in_pixels[x].r);
		int fp_g = INT_TO_FIXED(in_pixels[x].g);
		int fp_b = INT_TO_FIXED(in_pixels[x].b);

		int fp_rb_ratio = INT_TO_FIXED_DIV(65535, 31);
		int fp_g_ratio = INT_TO_FIXED_DIV(65535, 63);

		u16 r = FIXED_TO_INT_ROUND(FIXED_DIV(fp_r, fp_rb_ratio));
		u16 g = FIXED_TO_INT_ROUND(FIXED_DIV(fp_g, fp_g_ratio));
		u16 b = FIXED_TO_INT_ROUND(FIXED_DIV(fp_b, fp_rb_ratio));

		*dst_pixels = cpu_to_le16(r << 11 | g << 5 | b);
	}
}

plane_format_transform_func get_plane_fmt_transform_function(u32 format)
{
	if (format == DRM_FORMAT_ARGB8888)
@@ -209,6 +275,8 @@ plane_format_transform_func get_plane_fmt_transform_function(u32 format)
		return &ARGB16161616_to_argb_u16;
	else if (format == DRM_FORMAT_XRGB16161616)
		return &XRGB16161616_to_argb_u16;
	else if (format == DRM_FORMAT_RGB565)
		return &RGB565_to_argb_u16;
	else
		return NULL;
}
@@ -223,6 +291,8 @@ wb_format_transform_func get_wb_fmt_transform_function(u32 format)
		return &argb_u16_to_ARGB16161616;
	else if (format == DRM_FORMAT_XRGB16161616)
		return &argb_u16_to_XRGB16161616;
	else if (format == DRM_FORMAT_RGB565)
		return &argb_u16_to_RGB565;
	else
		return NULL;
}
diff --git a/drivers/gpu/drm/vkms/vkms_plane.c b/drivers/gpu/drm/vkms/vkms_plane.c
index 60054a85204a..94a8e412886f 100644
--- a/drivers/gpu/drm/vkms/vkms_plane.c
+++ b/drivers/gpu/drm/vkms/vkms_plane.c
@@ -14,14 +14,16 @@

static const u32 vkms_formats[] = {
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_XRGB16161616
	DRM_FORMAT_XRGB16161616,
	DRM_FORMAT_RGB565
};

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

static struct drm_plane_state *
diff --git a/drivers/gpu/drm/vkms/vkms_writeback.c b/drivers/gpu/drm/vkms/vkms_writeback.c
index cb63a5da9af1..98da7bee0f4b 100644
--- a/drivers/gpu/drm/vkms/vkms_writeback.c
+++ b/drivers/gpu/drm/vkms/vkms_writeback.c
@@ -16,7 +16,8 @@
static const u32 vkms_wb_formats[] = {
	DRM_FORMAT_XRGB8888,
	DRM_FORMAT_XRGB16161616,
	DRM_FORMAT_ARGB16161616
	DRM_FORMAT_ARGB16161616,
	DRM_FORMAT_RGB565
};

static const struct drm_connector_funcs vkms_wb_connector_funcs = {
-- 
2.30.2