[PATCH 0/8] drm/exynos: address more scenarios with wait_for_vblank

[Prathyush K]

This patchset has more fixes for fixing more issues related to wait for vblank.

Patch 1: add mixer apply function
	The mixer window enabled flag is being done in both exynos_drm_hdmi as
well as exynos_mixer. This patch moves the flag to one place and adds the
mixer apply function similar to fimd apply function.

Patch 2: fimd: call win_disable only when window is enabled
	Adds a condition to call win_disable only if the window is enabled.

Patch 3: enable vblank in fimd wait for vblank
	If vblank is disabled, then we turn enable vblank temporarily before
wait for vblank and disable it afterwards. This ensures that the wait will
not timeout.

Patch 4: fimd: clear channel before enabling iommu
	This patch is required if the fimd window channel is already active
before fimd probe. This could happen if we turn on fimd during uboot. This
patch ensures that we do not get a page fault upon iommu initialization. If
any channel is active, we disable the channel and wait for vblank.

Patch 5: mixer: do not finish a pageflip if layer update in progress
	Exynos5 supports only 2 layer updates for mixer. This patch
ensures each layer is updated only once per vsync. Also, in case a layer
update is pending, the irq handler exits early. This ensures there is
no corruption on screen as well as there is no page fault during buffer
freeing.

Patch 6: add complete_scanout interface
    Before freeing a framebuffer, we call complete_scanout encoder
function which just calls wait for vblank of all the encoders.
This is not a very optimized method since a framebuffer might not
be in use by a crtc and we end up waiting for vblank unnecessarily.
Instead, this patch modifies the wait_for_vblank interface to
complete_scanout interface. In this function, each crtc must
check if the fb is currently being used. If it is being used,
it must wait for vsync (or even disable a window if necessary)
and ensure that the buffer is no longer used by crtc before returning.
So if a crtc is not actually reading from the buffer, the complete
scanout function will just return and not wait for vsync.

Patch 7: hdmi: add complete_scanout function
Patch 8: fimd: add complete_scanout function
	These two patches add the respective complete_scanout functions
for fimd and mixer. These functions check the actual base and shadow
registers of fimd/mixer to see if a particular dma-address is in use
and will wait_for_vblank only if it is in use. Also for mixer, if the
base address matches the fb's dma address, then the window is disabled.
This is because a layer update is already set when the base register
was updated. So unless we disable the window, we cannot free the buffer.

Akshu Agrawal (1):
  drm/exynos: fimd: clear channel before enabling iommu

Prathyush K (6):
  drm/exynos: add mixer apply function
  drm/exynos: fimd: call win_disable only when window is enabled
  drm/exynos: enable vblank in fimd wait for vblank
  drm/exynos: add complete_scanout interface
  drm/exynos: hdmi: add complete_scanout function
  drm/exynos: fimd: add complete_scanout function

Sean Paul (1):
  drm/exynos: mixer: do not finish a pageflip if layer update in
    progress

 drivers/gpu/drm/exynos/exynos_drm_drv.h     |  7 ++-
 drivers/gpu/drm/exynos/exynos_drm_encoder.c | 23 ++++----
 drivers/gpu/drm/exynos/exynos_drm_encoder.h |  4 +-
 drivers/gpu/drm/exynos/exynos_drm_fb.c      | 13 ++++-
 drivers/gpu/drm/exynos/exynos_drm_fimd.c    | 81 ++++++++++++++++++++++++--
 drivers/gpu/drm/exynos/exynos_drm_hdmi.c    | 26 +++------
 drivers/gpu/drm/exynos/exynos_drm_hdmi.h    |  4 +-
 drivers/gpu/drm/exynos/exynos_mixer.c       | 90 ++++++++++++++++++++++++++---
 drivers/gpu/drm/exynos/regs-mixer.h         |  1 +
 include/video/samsung_fimd.h                |  1 +
 10 files changed, 202 insertions(+), 48 deletions(-)

-- 
1.8.0