kernel/linux.git/drivers/gpu/drm/amd/display/dc/dsc, branch linux-6.9.y

drm/amd/display: Fix division by zero in setup_dsc_config

2024-05-25T14:30:53+00:00

commit 130afc8a886183a94cf6eab7d24f300014ff87ba upstream. When slice_height is 0, the division by slice_height in the calculation of the number of slices will cause a division by zero driver crash. This leaves the kernel in a state that requires a reboot. This patch adds a check to avoid the division by zero. The stack trace below is for the 6.8.4 Kernel. I reproduced the issue on a Z16 Gen 2 Lenovo Thinkpad with a Apple Studio Display monitor connected via Thunderbolt. The amdgpu driver crashed with this exception when I rebooted the system with the monitor connected. kernel: ? die (arch/x86/kernel/dumpstack.c:421 arch/x86/kernel/dumpstack.c:434 arch/x86/kernel/dumpstack.c:447) kernel: ? do_trap (arch/x86/kernel/traps.c:113 arch/x86/kernel/traps.c:154) kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu kernel: ? do_error_trap (./arch/x86/include/asm/traps.h:58 arch/x86/kernel/traps.c:175) kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu kernel: ? exc_divide_error (arch/x86/kernel/traps.c:194 (discriminator 2)) kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu kernel: ? asm_exc_divide_error (./arch/x86/include/asm/idtentry.h:548) kernel: ? setup_dsc_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1053) amdgpu kernel: dc_dsc_compute_config (drivers/gpu/drm/amd/amdgpu/../display/dc/dsc/dc_dsc.c:1109) amdgpu After applying this patch, the driver no longer crashes when the monitor is connected and the system is rebooted. I believe this is the same issue reported for 3113. Reviewed-by: Rodrigo Siqueira Signed-off-by: Jose Fernandez Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3113 Signed-off-by: Rodrigo Siqueira Signed-off-by: Alex Deucher Cc: "Limonciello, Mario" Signed-off-by: Greg Kroah-Hartman

drm/amd/display: Fix timing bandwidth calculation for HDMI

2024-01-22T22:13:26+00:00

[Why && How] The current bandwidth calculation for timing doesn't account for certain HDMI modes overhead which leads to DSC can't be enabled. Add support to calculate the actual bandwidth for these HDMI modes. Reviewed-by: Chris Park Acked-by: Roman Li Signed-off-by: Leo (Hanghong) Ma Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Add DSC granular throughput adjustment

2023-11-29T21:49:23+00:00

[Why/How] Update DSC DPCD parsing to take granular throughput adjustment into consideration. Reviewed-by: Wenjing Liu Acked-by: Tom Chung Signed-off-by: Ilya Bakoulin Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Refactor DSC into component folder

2023-11-29T21:48:59+00:00

[why] To refactor DSC and make DSC files unit testable. [how] moved the dcnxx_dsc.c and .h files into corresponding dcn folders inside the dsc and cleared the linkage errors. Reviewed-by: Wenjing Liu Acked-by: Hamza Mahfooz Signed-off-by: Bhuvana Chandra Pinninti Signed-off-by: Alex Deucher

drm/amd/display: Allow 16 max_slices for DP2 DSC

2023-11-07T16:17:03+00:00

Enable 12 and 16 max_slices for DP2 DSC Reviewed-by: Alvin Lee Acked-by: Hersen Wu Signed-off-by: Fangzhi Zuo Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Add link encoding to timing BW calculation parameters

2023-07-18T15:15:51+00:00

[Why] There certain cases where the timing BW is dependent on the type of link encoding in use. Thus to calculate the correct BW required for a given timing, the link encoding should be added as a parameter. Reviewed-by: Wenjing Liu Acked-by: Alan Liu Signed-off-by: George Shen Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: Add stream overhead in BW calculations for 128b/132b

2023-07-18T15:15:45+00:00

[Why] Current BW calculations do not account for the additional padding added for uncompressed pixel-to-symbol packing. This results in X.Y being too low for 128b/132b SST streams in certain scenarios. If X.Y is too low, end user can observe image corruption. [How] Add function to calculate stream overhead to timing BW calculation for 128b/132b SST cases. Reviewed-by: Wenjing Liu Acked-by: Alan Liu Signed-off-by: George Shen Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: drop redundant memset() in get_available_dsc_slices()

2023-06-09T14:38:37+00:00

get_available_dsc_slices() returns the number of indices set, and all of the users of get_available_dsc_slices() don't cross the returned bound when iterating over available_slices[]. So, the memset() in get_available_dsc_slices() is redundant and can be dropped. Fixes: 97bda0322b8a ("drm/amd/display: Add DSC support for Navi (v2)") Reported-by: Christophe JAILLET Reviewed-by: Rodrigo Siqueira Signed-off-by: Hamza Mahfooz Signed-off-by: Alex Deucher

drm/amd/display: DSC policy override when ODM combine is forced

2023-04-18T20:28:52+00:00

[why] When we force ODM combine with DSC, we lose several 8 bit and 10 bit modes in validation and thus not able to use HDR. This is due to the number of horizontal slices used in DSC not properly being accounted for currently when 2:1 ODM Combine is forced. [how] Enforce at least two horizontal slices are used for DSC when ODM combine is forced. Reviewed-by: Nicholas Kazlauskas Acked-by: Qingqing Zhuo Signed-off-by: Nasir Osman Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher

drm/amd/display: convert link.h functions to function pointer style

2023-03-14T19:35:03+00:00

[Why & How] All dc subcomponents should call another dc component via function pointers stored in a component structure. This is part of dc coding convention since the beginning. The reason behind this is to improve encapsulation and polymorphism. The function contract is extracted into a single link service structure defined in link.h header file and implemented only in link_factory.c instead of spreading across multiple files in link component file structure. Reviewed-by: Jun Lei Acked-by: Qingqing Zhuo Signed-off-by: Wenjing Liu Tested-by: Daniel Wheeler Signed-off-by: Alex Deucher