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[ Upstream commita8f196a0fa] On VLV/CHV there is some kind of linkage between the cdclk frequency and the DP link frequency. The spec says: "For DP audio configuration, cdclk frequency shall be set to meet the following requirements: DP Link Frequency(MHz) | Cdclk frequency(MHz) 270 | 320 or higher 162 | 200 or higher" I suspect that would more accurately be expressed as "cdclk >= DP link clock", and in any case we can express it like that in the code because of the limited set of cdclk (200, 266, 320, 400 MHz) and link frequencies (162 and 270 MHz) we support. Without this we can end up in a situation where the cdclk is too low and enabling DP audio will kill the pipe. Happens eg. with 2560x1440 modes where the 266MHz cdclk is sufficient to pump the pixels (241.5 MHz dotclock) but is too low for the DP audio due to the link frequency being 270 MHz. v2: Spell out the cdclk and link frequencies we actually support Cc: stable@vger.kernel.org Tested-by: Stefan Gottwald <gottwald@igel.com> Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=111149 Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com> Link: https://patchwork.freedesktop.org/patch/msgid/20190717114536.22937-1-ville.syrjala@linux.intel.com Acked-by: Chris Wilson <chris@chris-wilson.co.uk> (cherry picked from commitbffb31f73b) Signed-off-by: Jani Nikula <jani.nikula@intel.com> Signed-off-by: Sasha Levin <sashal@kernel.org>
Linux kernel
============
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