Re: [PATCH 2/3] drm/i915: Move WaProgramL3SqcReg1Default:bdw to init_clock_gating()

Jesse Barnes
2015-05-21T20:17:20Z

On 05/19/2015 10:32 AM, ville.syrjala@linux.intel.com wrote:
> From: Ville Syrjälä <ville.syrjala@linux.intel.com>
>
> GEN8_L3SQCREG1 isn't saved in the context (verified by going through
> a context dump), and so we shouldn't be using the ring w/a code to
> initialize it. Also Bspec explicitly talks about MMIO and writing it
> with the CPU.
>
> Additionally there's another w/a WaTempDisableDOPClkGating:bdw which
> tells us to disable DOP clock gating around the GEN8_L3SQCREG1 write
> to make sure everyone notices the change. So let's do that as well.
>
> Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
> Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
> ---
> drivers/gpu/drm/i915/intel_pm.c | 10 ++++++++++
> drivers/gpu/drm/i915/intel_ringbuffer.c | 3 ---
> 2 files changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 206bd41..5ec56b6 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -6165,6 +6165,7 @@ static void broadwell_init_clock_gating(struct drm_device *dev)
> {
> struct drm_i915_private *dev_priv = dev->dev_private;
> enum pipe pipe;
> + uint32_t misccpctl;
>
> ilk_init_lp_watermarks(dev);
>
> @@ -6195,6 +6196,15 @@ static void broadwell_init_clock_gating(struct drm_device *dev)
> I915_WRITE(GEN8_UCGCTL6, I915_READ(GEN8_UCGCTL6) |
> GEN8_SDEUNIT_CLOCK_GATE_DISABLE);
>
> + /*
> + * WaProgramL3SqcReg1Default:bdw
> + * WaTempDisableDOPClkGating:bdw
> + */
> + misccpctl = I915_READ(GEN7_MISCCPCTL);
> + I915_WRITE(GEN7_MISCCPCTL, misccpctl & ~GEN7_DOP_CLOCK_GATE_ENABLE);
> + I915_WRITE(GEN8_L3SQCREG1, BDW_WA_L3SQCREG1_DEFAULT);
> + I915_WRITE(GEN7_MISCCPCTL, misccpctl);
> +
> lpt_init_clock_gating(dev);
> }
>
> diff --git a/drivers/gpu/drm/i915/intel_ringbuffer.c b/drivers/gpu/drm/i915/intel_ringbuffer.c
> index 9b96ed7..50cdd67 100644
> --- a/drivers/gpu/drm/i915/intel_ringbuffer.c
> +++ b/drivers/gpu/drm/i915/intel_ringbuffer.c
> @@ -853,9 +853,6 @@ static int bdw_init_workarounds(struct intel_engine_cs *ring)
> GEN6_WIZ_HASHING_MASK,
> GEN6_WIZ_HASHING_16x4);
>
> - /* WaProgramL3SqcReg1Default:bdw */
> - WA_WRITE(GEN8_L3SQCREG1, BDW_WA_L3SQCREG1_DEFAULT);
> -
> return 0;
> }
>
>

Reviewed-by: Jesse Barnes <jbarnes@virtuousgeek.org>