drm/i915: enable RC6 workaround on Haswell

For Haswell, on some of the early hardware revisions, it is possible to
run into issues when RC6 state is enabled and when pipes change state.

v2: add comment saying that this is for early revisions only.

v3: beautify as suggested by Daniel Vetter.

Signed-off-by: Eugeni Dodonov <eugeni.dodonov@intel.com>
Acked-by: Ben Widawsky <ben@bwidawsk.net>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
This commit is contained in:
Eugeni Dodonov 2012-07-02 11:51:10 -03:00 committed by Daniel Vetter
parent cad2a2d776
commit 1544d9d573
2 changed files with 15 additions and 0 deletions

View File

@ -4453,4 +4453,9 @@
#define SFUSE_STRAP_DDIC_DETECTED (1<<1)
#define SFUSE_STRAP_DDID_DETECTED (1<<0)
#define WM_DBG 0x45280
#define WM_DBG_DISALLOW_MULTIPLE_LP (1<<0)
#define WM_DBG_DISALLOW_MAXFIFO (1<<1)
#define WM_DBG_DISALLOW_SPRITE (1<<2)
#endif /* _I915_REG_H_ */

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@ -3467,6 +3467,16 @@ static void haswell_init_clock_gating(struct drm_device *dev)
/* WaDisable4x2SubspanOptimization */
I915_WRITE(CACHE_MODE_1,
_MASKED_BIT_ENABLE(PIXEL_SUBSPAN_COLLECT_OPT_DISABLE));
/* XXX: This is a workaround for early silicon revisions and should be
* removed later.
*/
I915_WRITE(WM_DBG,
I915_READ(WM_DBG) |
WM_DBG_DISALLOW_MULTIPLE_LP |
WM_DBG_DISALLOW_SPRITE |
WM_DBG_DISALLOW_MAXFIFO);
}
static void ivybridge_init_clock_gating(struct drm_device *dev)