[Intel-gfx] [PATCH 15/49] drm/i915/bxt: add GEN8_HDCUNIT_CLOCK_GATE_DISABLE_HDCREQ workaround

[Nick Hoath]

On 08/04/2015 14:38, Nick Hoath wrote:
> On 08/04/2015 14:10, Deak, Imre wrote:
>> On ke, 2015-04-08 at 14:04 +0100, Nick Hoath wrote:
>>> On 17/03/2015 09:39, Imre Deak wrote:
>>>> From: Ben Widawsky <benjamin.widawsky at intel.com>
>>>>
>>>> Signed-off-by: Ben Widawsky <ben at bwidawsk.net>
>>>> Signed-off-by: Imre Deak <imre.deak at intel.com>

Reviewed-by: Nick Hoath <nicholas.hoath at intel.com>

>>>> ---
>>>>    drivers/gpu/drm/i915/i915_reg.h | 1 +
>>>>    drivers/gpu/drm/i915/intel_pm.c | 4 +++-
>>>>    2 files changed, 4 insertions(+), 1 deletion(-)
>>>>
>>>> diff --git a/drivers/gpu/drm/i915/i915_reg.h
>>>> b/drivers/gpu/drm/i915/i915_reg.h
>>>> index 3369a11..b7ba061 100644
>>>> --- a/drivers/gpu/drm/i915/i915_reg.h
>>>> +++ b/drivers/gpu/drm/i915/i915_reg.h
>>>> @@ -6104,6 +6104,7 @@ enum skl_disp_power_wells {
>>>>    #define GEN8_UCGCTL6                0x9430
>>>>    #define   GEN8_GAPSUNIT_CLOCK_GATE_DISABLE    (1<<24)
>>>>    #define   GEN8_SDEUNIT_CLOCK_GATE_DISABLE    (1<<14)
>>>> +#define   GEN8_HDCUNIT_CLOCK_GATE_DISABLE_HDCREQ (1<<28)
>>>>
>>>>    #define GEN6_GFXPAUSE                0xA000
>>>>    #define GEN6_RPNSWREQ                0xA008
>>>> diff --git a/drivers/gpu/drm/i915/intel_pm.c
>>>> b/drivers/gpu/drm/i915/intel_pm.c
>>>> index d5dd0b3..52d3c02 100644
>>>> --- a/drivers/gpu/drm/i915/intel_pm.c
>>>> +++ b/drivers/gpu/drm/i915/intel_pm.c
>>>> @@ -103,10 +103,12 @@ static void bxt_init_clock_gating(struct
>>>> drm_device *dev)
>>>>        /*
>>>>         * FIXME:
>>>>         * GEN8_SDEUNIT_CLOCK_GATE_DISABLE applies on A0 only.
>>>> +     * GEN8_HDCUNIT_CLOCK_GATE_DISABLE_HDCREQ applies on 3x6 GT
>>>> SKUs only.
>
> Shouldn't this WA therefore have a check for 3x6 around it?
>
>>>>         */
>>>>         /* WaDisableSDEUnitClockGating:bxt */
>>>
>>> I can't find where WaDisableSDEUnitClockGating is listed as required for
>>> BXT?
>>
>> It's specified in BSpec GEN8_UCGCTL6 (0x9430) as required for BXT A0.
>>
>> --Imre
>>
>