drm/amd/display: Fix fractional fb divider in set_pixel_clock_v3
commit 10507478468f165ea681605d133991ed05cdff62 upstream. For later VBIOS versions, the fractional feedback divider is calculated as the remainder of dividing the feedback divider by a factor, which is set to 1000000. For reference, see: - calculate_fb_and_fractional_fb_divider - calc_pll_max_vco_construct However, in case of old VBIOS versions that have set_pixel_clock_v3, they only have 1 byte available for the fractional feedback divider, and it's expected to be set to the remainder from dividing the feedback divider by 10. For reference see the legacy display code: - amdgpu_pll_compute - amdgpu_atombios_crtc_program_pll This commit fixes set_pixel_clock_v3 by dividing the fractional feedback divider passed to the function by 100000. Fixes: 4562236b ("drm/amd/dc: Add dc display driver (v2)") Signed-off-by:Timur Kristóf <timur.kristof@gmail.com> Acked-by:
Alex Deucher <alexander.deucher@amd.com> Reviewed-by:
Rodrigo Siqueira <siqueira@igalia.com> Reviewed-by:
Alex Hung <alex.hung@amd.com> Signed-off-by:
Alex Deucher <alexander.deucher@amd.com> (cherry picked from commit 027e7acc7e17802ebf28e1edb88a404836ad50d6) Cc: stable@vger.kernel.org Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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