drm/i915/cnl: WaDisableI2mCycleOnWRPort
On CNL B0 stepping GAM is not able to detect some deadlock
condition and then rise the rise the gam_coh_flush.
WA database and spec both mentions to set 4AB8[24]=1 as
workaround. Although register offset 0x4AB8 is not
documented for any platform.
References: HSD#
1945815, BSID#1112
Cc: Mika Kuoppala <[email protected]>
Signed-off-by: Rodrigo Vivi <[email protected]>
Reviewed-by: Mika Kuoppala <[email protected]>
Link: https://patchwork.freedesktop.org/patch/msgid/[email protected]