In case the LCDIFv3 is used to drive a 4k panel via i.MX8MP HDMI bridge,
the LCDIFv3 becomes susceptible to FIFO underflows, these lead to nasty
flicker of the image on the panel, or image being shifted by half frame
horizontally every second frame. The flicker can be easily triggered by
running 3D application on top of weston compositor, like neverball or
chromium. Surprisingly glmark2-es2-wayland or glmark2-es2-drm does not
trigger this effect so easily.
Configure the FIFO Panic threshold register and enable the FIFO Panic
mode, which internally boosts the NoC interconnect priority for LCDIFv3
transactions in case of possible underflow. This mitigates the flicker
effect on 4k panels as well.
Fixes: 9db35bb349 ("drm: lcdif: Add support for i.MX8MP LCDIF variant")
Signed-off-by: Marek Vasut <marex@denx.de>
Tested-by: Liu Ying <victor.liu@nxp.com> # i.MX8mp EVK
Reviewed-by: Liu Ying <victor.liu@nxp.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20221101152629.21768-1-marex@denx.de
Up to and including v1.3, HDMI supported limited quantization range only
for YCbCr. HDMI v1.4 introduced selectable quantization ranges, but this
feature isn't supported in the dw-hdmi driver that is used in
conjunction with the LCDIF in the i.MX8MP. The HDMI YCbCr output is thus
always advertised in the AVI infoframe as limited range.
The LCDIF driver, on the other hand, configures the CSC to produce full
range YCbCr. This mismatch results in loss of details and incorrect
colours. Fix it by switching to limited range YCbCr.
The coefficients are copied from drivers/media/platforms/nxp/imx-pxp.c
for coherency, as the hardware is most likely identical.
Fixes: 9db35bb349 ("drm: lcdif: Add support for i.MX8MP LCDIF variant")
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Kieran Bingham <kieran.bingham@ideasonboard.com>
Reviewed-by: Liu Ying <victor.liu@nxp.com>
Signed-off-by: Marek Vasut <marex@denx.de>
Link: https://patchwork.freedesktop.org/patch/msgid/20220930083955.31580-4-laurent.pinchart@ideasonboard.com
Rename "GEM CMA" helpers to "GEM DMA" helpers - considering the
hierarchy of APIs (mm/cma -> dma -> gem dma) calling them "GEM
DMA" seems to be more applicable.
Besides that, commit e57924d4ae ("drm/doc: Task to rename CMA helpers")
requests to rename the CMA helpers and implies that people seem to be
confused about the naming.
In order to do this renaming the following script was used:
```
#!/bin/bash
DIRS="drivers/gpu include/drm Documentation/gpu"
REGEX_SYM_UPPER="[0-9A-Z_\-]"
REGEX_SYM_LOWER="[0-9a-z_\-]"
REGEX_GREP_UPPER="(${REGEX_SYM_UPPER}*)(GEM)_CMA_(${REGEX_SYM_UPPER}*)"
REGEX_GREP_LOWER="(${REGEX_SYM_LOWER}*)(gem)_cma_(${REGEX_SYM_LOWER}*)"
REGEX_SED_UPPER="s/${REGEX_GREP_UPPER}/\1\2_DMA_\3/g"
REGEX_SED_LOWER="s/${REGEX_GREP_LOWER}/\1\2_dma_\3/g"
# Find all upper case 'CMA' symbols and replace them with 'DMA'.
for ff in $(grep -REHl "${REGEX_GREP_UPPER}" $DIRS)
do
sed -i -E "$REGEX_SED_UPPER" $ff
done
# Find all lower case 'cma' symbols and replace them with 'dma'.
for ff in $(grep -REHl "${REGEX_GREP_LOWER}" $DIRS)
do
sed -i -E "$REGEX_SED_LOWER" $ff
done
# Replace all occurrences of 'CMA' / 'cma' in comments and
# documentation files with 'DMA' / 'dma'.
for ff in $(grep -RiHl " cma " $DIRS)
do
sed -i -E "s/ cma / dma /g" $ff
sed -i -E "s/ CMA / DMA /g" $ff
done
# Rename all 'cma_obj's to 'dma_obj'.
for ff in $(grep -RiHl "cma_obj" $DIRS)
do
sed -i -E "s/cma_obj/dma_obj/g" $ff
done
```
Only a few more manual modifications were needed, e.g. reverting the
following modifications in some DRM Kconfig files
- select CMA if HAVE_DMA_CONTIGUOUS
+ select DMA if HAVE_DMA_CONTIGUOUS
as well as manually picking the occurrences of 'CMA'/'cma' in comments and
documentation which relate to "GEM CMA", but not "FB CMA".
Also drivers/gpu/drm/Makefile was fixed up manually after renaming
drm_gem_cma_helper.c to drm_gem_dma_helper.c.
This patch is compile-time tested building a x86_64 kernel with
`make allyesconfig && make drivers/gpu/drm`.
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> #drivers/gpu/drm/arm
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220802000405.949236-4-dakr@redhat.com
Rename "FB CMA" helpers to "FB DMA" helpers - considering the hierarchy
of APIs (mm/cma -> dma -> fb dma) calling them "FB DMA" seems to be
more applicable.
Besides that, commit e57924d4ae ("drm/doc: Task to rename CMA helpers")
requests to rename the CMA helpers and implies that people seem to be
confused about the naming.
In order to do this renaming the following script was used:
```
#!/bin/bash
DIRS="drivers/gpu include/drm Documentation/gpu"
REGEX_SYM_UPPER="[0-9A-Z_\-]"
REGEX_SYM_LOWER="[0-9a-z_\-]"
REGEX_GREP_UPPER="(${REGEX_SYM_UPPER}*)(FB)_CMA_(${REGEX_SYM_UPPER}*)"
REGEX_GREP_LOWER="(${REGEX_SYM_LOWER}*)(fb)_cma_(${REGEX_SYM_LOWER}*)"
REGEX_SED_UPPER="s/${REGEX_GREP_UPPER}/\1\2_DMA_\3/g"
REGEX_SED_LOWER="s/${REGEX_GREP_LOWER}/\1\2_dma_\3/g"
# Find all upper case 'CMA' symbols and replace them with 'DMA'.
for ff in $(grep -REHl "${REGEX_GREP_UPPER}" $DIRS)
do
sed -i -E "$REGEX_SED_UPPER" $ff
done
# Find all lower case 'cma' symbols and replace them with 'dma'.
for ff in $(grep -REHl "${REGEX_GREP_LOWER}" $DIRS)
do
sed -i -E "$REGEX_SED_LOWER" $ff
done
# Replace all occurrences of 'CMA' / 'cma' in comments and
# documentation files with 'DMA' / 'dma'.
for ff in $(grep -RiHl " cma " $DIRS)
do
sed -i -E "s/ cma / dma /g" $ff
sed -i -E "s/ CMA / DMA /g" $ff
done
```
Only a few more manual modifications were needed, e.g. reverting the
following modifications in some DRM Kconfig files
- select CMA if HAVE_DMA_CONTIGUOUS
+ select DMA if HAVE_DMA_CONTIGUOUS
as well as manually picking the occurrences of 'CMA'/'cma' in comments and
documentation which relate to "FB CMA", but not "GEM CMA".
This patch is compile-time tested building a x86_64 kernel with
`make allyesconfig && make drivers/gpu/drm`.
Acked-by: Sam Ravnborg <sam@ravnborg.org>
Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Danilo Krummrich <dakr@redhat.com>
Reviewed-by: Liviu Dudau <liviu.dudau@arm.com> #drivers/gpu/drm/arm
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20220802000405.949236-3-dakr@redhat.com