s/Arun/Jeff + Jon/ This W/A would seem to be breaking context isolation as it is not context saved. Thus it is a candidate for being removed. I have to say I did not get any wiser from reading the HSD, so can you guys bring some insight here? Regards, Joonas On Wed, 2017-11-01 at 22:44 +0000, Chris Wilson wrote: > Quoting Arun Siluvery (2016-06-03 12:40:00) > > Kernel only need to add a register to HW whitelist, required for a > > preemption related issue. > > > > Reference: HSD#2131039 > > Signed-off-by: Arun Siluvery <arun.siluvery@xxxxxxxxxxxxxxx> > > --- > > drivers/gpu/drm/i915/i915_reg.h | 1 + > > drivers/gpu/drm/i915/intel_ringbuffer.c | 5 +++++ > > 2 files changed, 6 insertions(+) > > > > diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h > > index e307725..1f6040a 100644 > > --- a/drivers/gpu/drm/i915/i915_reg.h > > +++ b/drivers/gpu/drm/i915/i915_reg.h > > @@ -6072,6 +6072,7 @@ enum skl_disp_power_wells { > > #define GEN9_TSG_BARRIER_ACK_DISABLE (1<<8) > > > > #define GEN9_CS_DEBUG_MODE1 _MMIO(0x20ec) > > +#define GEN9_CTX_PREEMPT_REG _MMIO(0x2248) > > #define GEN8_CS_CHICKEN1 _MMIO(0x2580) > > > > /* GEN7 chicken */ > > diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c > > index 8d35a39..1f9d3a4 100644 > > --- a/drivers/gpu/drm/i915/intel_ringbuffer.c > > +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c > > @@ -987,6 +987,11 @@ static int gen9_init_workarounds(struct intel_engine_cs *engine) > > I915_WRITE(GEN8_L3SQCREG4, (I915_READ(GEN8_L3SQCREG4) | > > GEN8_LQSC_FLUSH_COHERENT_LINES)); > > > > + /* WaVFEStateAfterPipeControlwithMediaStateClear:skl,bxt */ > > + ret= wa_ring_whitelist_reg(engine, GEN9_CTX_PREEMPT_REG); > > + if (ret) > > + return ret; > > What is for exactly? This register is not context saved, so... > -Chris > _______________________________________________ > Intel-gfx mailing list > Intel-gfx@xxxxxxxxxxxxxxxxxxxxx > https://lists.freedesktop.org/mailman/listinfo/intel-gfx -- Joonas Lahtinen Open Source Technology Center Intel Corporation _______________________________________________ Intel-gfx mailing list Intel-gfx@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/intel-gfx