Re: [PATCH v3] drm/i915/chv: Implement WaDisableShadowRegForCpd

Deepak S
2015-04-16T03:22:29Z

On Thursday 16 April 2015 12:09 AM, Ville Syrjälä wrote:
> On Wed, Apr 15, 2015 at 07:41:39PM +0530, deepak.s@linux.intel.com wrote:
>> From: Deepak S <deepak.s@linux.intel.com>
>>
>> This WA is avoid problem between shadow vs wake FIFO unload
>> problem during CPD/RC6 transactions on CHV.
>>
>> v2: Define individual bits GTFIFOCTL (Ville)
>>
>> v3: move WA to uncore_early_sanitize (ville)
>>
>> Signed-off-by: Deepak S <deepak.s@linux.intel.com>
>> ---
>> drivers/gpu/drm/i915/i915_reg.h | 2 ++
>> drivers/gpu/drm/i915/intel_uncore.c | 8 ++++++++
>> 2 files changed, 10 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
>> index 9c97842..a642a58 100644
>> --- a/drivers/gpu/drm/i915/i915_reg.h
>> +++ b/drivers/gpu/drm/i915/i915_reg.h
>> @@ -6206,6 +6206,8 @@ enum skl_disp_power_wells {
>> #define GTFIFOCTL 0x120008
>> #define GT_FIFO_FREE_ENTRIES_MASK 0x7f
>> #define GT_FIFO_NUM_RESERVED_ENTRIES 20
>> +#define GT_FIFO_CTL_BLOCK_ALL_POLICY_STALL (1 << 12)
>> +#define GT_FIFO_CTL_RC6_POLICY_STALL (1 << 11)
>>
>> #define HSW_IDICR 0x9008
>> #define IDIHASHMSK(x) (((x) & 0x3f) << 16)
>> diff --git a/drivers/gpu/drm/i915/intel_uncore.c b/drivers/gpu/drm/i915/intel_uncore.c
>> index d96d15f..26d6dda 100644
>> --- a/drivers/gpu/drm/i915/intel_uncore.c
>> +++ b/drivers/gpu/drm/i915/intel_uncore.c
>> @@ -360,6 +360,14 @@ static void __intel_uncore_early_sanitize(struct drm_device *dev,
>> __raw_i915_write32(dev_priv, GTFIFODBG,
>> __raw_i915_read32(dev_priv, GTFIFODBG));
>>
>> + /* WaDisableShadowRegForCpd */
> I couldn't find this w/a name anywhere official, but I guess it's fine.
> Should be WaDisableShadowRegForCpd:chv though. Otherwise looks good, so
>
> Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>

Thanks Ville for reviewing. I this the WA still not added to the chv list.

>> + if (IS_CHERRYVIEW(dev)) {
>> + __raw_i915_write32(dev_priv, GTFIFOCTL,
>> + __raw_i915_read32(dev_priv, GTFIFOCTL) |
>> + GT_FIFO_CTL_BLOCK_ALL_POLICY_STALL |
>> + GT_FIFO_CTL_RC6_POLICY_STALL);
>> + }
>> +
>> intel_uncore_forcewake_reset(dev, restore_forcewake);
>> }
>>
>> --
>> 1.9.1