[Intel-gfx] [PATCH v3 08/22] drm/i915: Create a new category of display WAs

[Chris Wilson]

Quoting Oscar Mateo (2017-10-13 21:54:02)
> Display workarounds do not need to be re-applied on a GPU reset
> (this is, in Ville's words: "at the very least wasted effort [...]
> and could even be actively harmful in case we end up clobbering
> something the current display configuration depends on"). Therefore,
> they have to be applied in a different place that GT ones so they
> deserve their own category.
> 
> Actually populating this is left for future patches: we have to
> start moving WAs from init_clock_gating into either GT or
> Display functions, and this requires a good deal of careful code
> reviewing.
> 
> Suggested-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Signed-off-by: Oscar Mateo <oscar.mateo at intel.com>
> Cc: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala at linux.intel.com>
> Cc: Rodrigo Vivi <rodrigo.vivi at intel.com>
> ---
>  drivers/gpu/drm/i915/i915_drv.c          |   2 +-
>  drivers/gpu/drm/i915/i915_drv.h          |   3 +
>  drivers/gpu/drm/i915/intel_pm.c          |   2 +
>  drivers/gpu/drm/i915/intel_workarounds.c | 154 +++++++++++++++++++++++++++++--
>  drivers/gpu/drm/i915/intel_workarounds.h |   3 +-
>  5 files changed, 155 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/i915_drv.c b/drivers/gpu/drm/i915/i915_drv.c
> index 27993eb..6e9a0da 100644
> --- a/drivers/gpu/drm/i915/i915_drv.c
> +++ b/drivers/gpu/drm/i915/i915_drv.c
> @@ -887,7 +887,7 @@ static int i915_driver_init_early(struct drm_i915_private *dev_priv,
>         BUG_ON(device_info->gen > sizeof(device_info->gen_mask) * BITS_PER_BYTE);
>         device_info->gen_mask = BIT(device_info->gen - 1);
>  
> -       ret = intel_gt_workarounds_init(dev_priv);
> +       ret = intel_mmio_workarounds_init(dev_priv);

Momentary panic over. I'm going to suggest those that we carry the
init_early nomenclature over. It's very important that we stress that we
are *only* building the lists at this time and not touching the hw.

With that change backported to intel_gt_workarounds_init_early()
Reviewed-by: Chris Wilson <chris at chris-wilson.co.uk>
-Chris