[PATCH v6 1/3] drm/vkms: Decouple crc operations from composer

From: Rodrigo Siqueira
Date: Sun Aug 30 2020 - 10:20:59 EST


In the vkms_composer.c, some of the functions related to CRC and compose
have interdependence between each other. This patch reworks some
functions inside vkms_composer to make crc and composer computation
decoupled.

This patch is preparation work for making vkms able to support new
features.

Tested-by: Melissa Wen <melissa.srw@xxxxxxxxx>
Signed-off-by: Rodrigo Siqueira <rodrigosiqueiramelo@xxxxxxxxx>
---
drivers/gpu/drm/vkms/vkms_composer.c | 49 ++++++++++++++++------------
1 file changed, 29 insertions(+), 20 deletions(-)

diff --git a/drivers/gpu/drm/vkms/vkms_composer.c b/drivers/gpu/drm/vkms/vkms_composer.c
index eaecc5a6c5db..f67d1baf1942 100644
--- a/drivers/gpu/drm/vkms/vkms_composer.c
+++ b/drivers/gpu/drm/vkms/vkms_composer.c
@@ -131,35 +131,31 @@ static void compose_cursor(struct vkms_composer *cursor_composer,
primary_composer, cursor_composer);
}

-static uint32_t _vkms_get_crc(struct vkms_composer *primary_composer,
- struct vkms_composer *cursor_composer)
+static int compose_planes(void **vaddr_out,
+ struct vkms_composer *primary_composer,
+ struct vkms_composer *cursor_composer)
{
struct drm_framebuffer *fb = &primary_composer->fb;
struct drm_gem_object *gem_obj = drm_gem_fb_get_obj(fb, 0);
struct vkms_gem_object *vkms_obj = drm_gem_to_vkms_gem(gem_obj);
- void *vaddr_out = kzalloc(vkms_obj->gem.size, GFP_KERNEL);
- u32 crc = 0;

- if (!vaddr_out) {
- DRM_ERROR("Failed to allocate memory for output frame.");
- return 0;
+ if (!*vaddr_out) {
+ *vaddr_out = kzalloc(vkms_obj->gem.size, GFP_KERNEL);
+ if (!*vaddr_out) {
+ DRM_ERROR("Cannot allocate memory for output frame.");
+ return -ENOMEM;
+ }
}

- if (WARN_ON(!vkms_obj->vaddr)) {
- kfree(vaddr_out);
- return crc;
- }
+ if (WARN_ON(!vkms_obj->vaddr))
+ return -EINVAL;

- memcpy(vaddr_out, vkms_obj->vaddr, vkms_obj->gem.size);
+ memcpy(*vaddr_out, vkms_obj->vaddr, vkms_obj->gem.size);

if (cursor_composer)
- compose_cursor(cursor_composer, primary_composer, vaddr_out);
+ compose_cursor(cursor_composer, primary_composer, *vaddr_out);

- crc = compute_crc(vaddr_out, primary_composer);
-
- kfree(vaddr_out);
-
- return crc;
+ return 0;
}

/**
@@ -180,9 +176,11 @@ void vkms_composer_worker(struct work_struct *work)
struct vkms_output *out = drm_crtc_to_vkms_output(crtc);
struct vkms_composer *primary_composer = NULL;
struct vkms_composer *cursor_composer = NULL;
+ void *vaddr_out = NULL;
u32 crc32 = 0;
u64 frame_start, frame_end;
bool crc_pending;
+ int ret;

spin_lock_irq(&out->composer_lock);
frame_start = crtc_state->frame_start;
@@ -206,14 +204,25 @@ void vkms_composer_worker(struct work_struct *work)
if (crtc_state->num_active_planes == 2)
cursor_composer = crtc_state->active_planes[1]->composer;

- if (primary_composer)
- crc32 = _vkms_get_crc(primary_composer, cursor_composer);
+ if (!primary_composer)
+ return;
+
+ ret = compose_planes(&vaddr_out, primary_composer, cursor_composer);
+ if (ret) {
+ if (ret == -EINVAL)
+ kfree(vaddr_out);
+ return;
+ }
+
+ crc32 = compute_crc(vaddr_out, primary_composer);

/*
* The worker can fall behind the vblank hrtimer, make sure we catch up.
*/
while (frame_start <= frame_end)
drm_crtc_add_crc_entry(crtc, true, frame_start++, &crc32);
+
+ kfree(vaddr_out);
}

static const char * const pipe_crc_sources[] = {"auto"};
--
2.28.0