[09/80] drm/i915: Turn on another required clock gating bit on gen6.

Greg KH
2011-12-07T16:16:41Z

From: Eric Anholt <eric@anholt.net>

commit 9ca1d10d748e56964de95e3ed80211b192f56cf4 upstream.

Unlike the previous one, I don't have known testcases it fixes. I'd
rather not go through the same debug cycle on whatever testcases those
might be.

Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

---
drivers/gpu/drm/i915/i915_reg.h | 1 +
drivers/gpu/drm/i915/intel_display.c | 7 ++++++-
2 files changed, 7 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3372,6 +3372,7 @@

#define GEN6_UCGCTL2 0x9404
# define GEN6_RCPBUNIT_CLOCK_GATE_DISABLE (1 << 12)
+# define GEN6_RCCUNIT_CLOCK_GATE_DISABLE (1 << 11)

#define GEN6_RPNSWREQ 0xA008
#define GEN6_TURBO_DISABLE (1<<31)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -7411,8 +7411,13 @@ static void gen6_init_clock_gating(struc
* some amount of runtime in the Mesa "fire" demo, and Unigine
* Sanctuary and Tropics, and apparently anything else with
* alpha test or pixel discard.
+ *
+ * According to the spec, bit 11 (RCCUNIT) must also be set,
+ * but we didn't debug actual testcases to find it out.
*/
- I915_WRITE(GEN6_UCGCTL2, GEN6_RCPBUNIT_CLOCK_GATE_DISABLE);
+ I915_WRITE(GEN6_UCGCTL2,
+ GEN6_RCPBUNIT_CLOCK_GATE_DISABLE |
+ GEN6_RCCUNIT_CLOCK_GATE_DISABLE);

/*
* According to the spec the following bits should be