4.5-stable review patch. If anyone has any objections, please let me know.
------------------ From: Mika Kuoppala <[email protected]> commit 510650e8b2ab965931b35e9813467439d4df0b9c upstream. Experiments with heaven 4.0 benchmark and skylake gt3e (rev 0xa) suggest that WaForceContextSaveRestoreNonCoherent is needed for all revs. Extending this to all revs cures a gpu hang with rev 0xa when running heaven4.0 gpu benchmark. We have been here before, with problems enabling gt4e and extending up to revision F0 instead of false claims of bspec of E0 only. See commit <e238659ddd88> ("drm/i915/skl: Default to noncoherent access up to F0"). In retrospect we should have covered this with this big blanket back then already, as E0 vs F0 discrepancy was suspicious enough. Previously the WaForceEnableNonCoherent has been tied to context non-coherence, atleast in relevant hsds. So keep this tie and extended this alongside. Cc: Abdiel Janulgue <[email protected]> Cc: Ben Widawsky <[email protected]> Cc: Timo Aaltonen <[email protected]> Reported-by: Mike Lothian <[email protected]> References: https://bugs.freedesktop.org/show_bug.cgi?id=93491 Signed-off-by: Mika Kuoppala <[email protected]> Reviewed-by: Ben Widawsky <[email protected]> Tested-by: Timo Aaltonen <[email protected]> Link: http://patchwork.freedesktop.org/patch/msgid/[email protected] (cherry picked from commit 97ea6be161c55dec896b65c95157d953c330ae05) Signed-off-by: Jani Nikula <[email protected]> Signed-off-by: Greg Kroah-Hartman <[email protected]> --- drivers/gpu/drm/i915/intel_ringbuffer.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/intel_ringbuffer.c +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c @@ -951,7 +951,7 @@ static int gen9_init_workarounds(struct /* WaForceContextSaveRestoreNonCoherent:skl,bxt */ tmp = HDC_FORCE_CONTEXT_SAVE_RESTORE_NON_COHERENT; - if (IS_SKL_REVID(dev, SKL_REVID_F0, SKL_REVID_F0) || + if (IS_SKL_REVID(dev, SKL_REVID_F0, REVID_FOREVER) || IS_BXT_REVID(dev, BXT_REVID_B0, REVID_FOREVER)) tmp |= HDC_FORCE_CSR_NON_COHERENT_OVR_DISABLE; WA_SET_BIT_MASKED(HDC_CHICKEN0, tmp); @@ -1044,7 +1044,8 @@ static int skl_init_workarounds(struct i WA_SET_BIT_MASKED(HIZ_CHICKEN, BDW_HIZ_POWER_COMPILER_CLOCK_GATING_DISABLE); - if (IS_SKL_REVID(dev, 0, SKL_REVID_F0)) { + /* This is tied to WaForceContextSaveRestoreNonCoherent */ + if (IS_SKL_REVID(dev, 0, REVID_FOREVER)) { /* *Use Force Non-Coherent whenever executing a 3D context. This * is a workaround for a possible hang in the unlikely event
