On Thu, 18 Oct 2012 14:44:35 +0200
Daniel Vetter <daniel.vetter at ffwll.ch> wrote:
> Single-threaded forcewake was only used on some early pre-production
> ivybridge machines, all the latest ones should use mt forcewake. And
> we already assume this in other places of the code (e.g. DERRMR
> support in the ddx, or the latest intel_gt_reset patch to reset any
> lingering forcewake references left behind by the bios), so don't
> bother here, too.
>
> Signed-off-by: Daniel Vetter <daniel.vetter at ffwll.ch>
> ---
> drivers/gpu/drm/i915/intel_pm.c | 31 ++++---------------------------
> 1 file changed, 4 insertions(+), 27 deletions(-)
>
> diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c
> index 2b3cddf..568c98d 100644
> --- a/drivers/gpu/drm/i915/intel_pm.c
> +++ b/drivers/gpu/drm/i915/intel_pm.c
> @@ -4146,35 +4146,12 @@ void intel_gt_init(struct drm_device *dev)
> if (IS_VALLEYVIEW(dev)) {
> dev_priv->gt.force_wake_get = vlv_force_wake_get;
> dev_priv->gt.force_wake_put = vlv_force_wake_put;
> - } else if (INTEL_INFO(dev)->gen >= 6) {
> + } else if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev)) {
> + dev_priv->gt.force_wake_get = __gen6_gt_force_wake_mt_get;
> + dev_priv->gt.force_wake_put = __gen6_gt_force_wake_mt_put;
> + } else if (IS_GEN6(dev)) {
> dev_priv->gt.force_wake_get = __gen6_gt_force_wake_get;
> dev_priv->gt.force_wake_put = __gen6_gt_force_wake_put;
> -
> - /* IVB configs may use multi-threaded forcewake */
> - if (IS_IVYBRIDGE(dev) || IS_HASWELL(dev)) {
> - u32 ecobus;
> -
> - /* A small trick here - if the bios hasn't configured
> - * MT forcewake, and if the device is in RC6, then
> - * force_wake_mt_get will not wake the device and the
> - * ECOBUS read will return zero. Which will be
> - * (correctly) interpreted by the test below as MT
> - * forcewake being disabled.
> - */
> - mutex_lock(&dev->struct_mutex);
> - __gen6_gt_force_wake_mt_get(dev_priv);
> - ecobus = I915_READ_NOTRACE(ECOBUS);
> - __gen6_gt_force_wake_mt_put(dev_priv);
> - mutex_unlock(&dev->struct_mutex);
> -
> - if (ecobus & FORCEWAKE_MT_ENABLE) {
> - DRM_DEBUG_KMS("Using MT version of forcewake\n");
> - dev_priv->gt.force_wake_get =
> - __gen6_gt_force_wake_mt_get;
> - dev_priv->gt.force_wake_put =
> - __gen6_gt_force_wake_mt_put;
> - }
> - }
> }
> }
>
Reviewed-by: Jesse Barnes <jbarnes at virtuousgeek.org>
Pretty sure it was just early, pre-production IVB that didn't use MT,
so this should be safe.
--
Jesse Barnes, Intel Open Source Technology Center
