[Intel-gfx] [PATCH 2/4] drm/i915: Convert sandybridge_pcode_*() to use intel_wait_for_register()

[Matt Turner]

On Thu, Jun 30, 2016 at 4:30 AM, Chris Wilson <chris at chris-wilson.co.uk> wrote:
> We want to replace the inline wait_for() with an out-of-line hybrid
> busy/sleep wait_for() in the hopes of speeding up the communication wit
> the PCode unit.
>
> Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
> Cc: Mika Kuoppala <mika.kuoppala at intel.com>
> Cc: Ville Syrjälä <ville.syrjala at linux.intel.com>
> Cc: Tvrtko Ursulin <tvrtko.ursulin at intel.com>
> ---
>  drivers/gpu/drm/i915/intel_pm.c | 43 +++++++++++++++++++++++++++--------------
>  1 file changed, 28 insertions(+), 15 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index d7f8ba89d2a5..f84bf253d04a 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -7623,46 +7623,59 @@ int sandybridge_pcode_read(struct drm_i915_private *dev_priv, u32 mbox, u32 *val
>  {
>         WARN_ON(!mutex_is_locked(&dev_priv->rps.hw_lock));
>
> -       if (I915_READ(GEN6_PCODE_MAILBOX) & GEN6_PCODE_READY) {
> +       /* GEN6_PCODE_* are outside of the forcewake domain, we can
> +        * use te fw I915_READ variants to reduce the amount of work

typo: te -> the