drm/i915: fix intel_init_power_wells

The current code was wrong in many different ways, so this is a full
rewrite. We don't have "different power wells for different parts of
the GPU", we have a single power well, but we have multiple registers
that can be used to request enabling/disabling the power well. So
let's be a good citizen and only use the register we're suppose to
use, except when we're loading the driver, where we clear the request
made by the BIOS.

If any of the registers is requesting the power well to be enabled, it
will be enabled. If none of the registers is requesting the power well
to be enabled, it will be disabled.

For now we're just forcing the power well to be enabled, but in the
next commits we'll change this.

V2:
  - Remove debug messages that could be misleading due to possible
    race conditions with KVMr, Debug and BIOS.
  - Don't wait on disabling: after a conversaion with a hardware
    engineer we discovered that the "restriction" on bit 31 is just
    for the "enable" case, and we don't even need to wait on the
    "disable" case.

Signed-off-by: Paulo Zanoni <paulo.r.zanoni@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Paulo Zanoni
2013-01-25 16:59:11 -02:00
committed by Daniel Vetter
parent 80a75f7c44
commit fa42e23c10
4 changed files with 47 additions and 27 deletions

View File

@@ -667,7 +667,7 @@ extern void intel_update_fbc(struct drm_device *dev);
extern void intel_gpu_ips_init(struct drm_i915_private *dev_priv);
extern void intel_gpu_ips_teardown(void);
extern void intel_init_power_wells(struct drm_device *dev);
extern void intel_init_power_well(struct drm_device *dev);
extern void intel_enable_gt_powersave(struct drm_device *dev);
extern void intel_disable_gt_powersave(struct drm_device *dev);
extern void gen6_gt_check_fifodbg(struct drm_i915_private *dev_priv);