drm/i915: apply timing generator bug workaround on CPT and PPT

On CougarPoint and PantherPoint PCH chips, the timing generator may fail
to start after DP training completes.  This is due to a bug in the
FDI autotraining detect logic (which will stall the timing generator and
re-enable it once training completes), so disable it to avoid silent DP
mode setting failures.

Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Keith Packard <keithp@keithp.com>
This commit is contained in:
Jesse Barnes 2011-07-27 11:51:40 -07:00 committed by Keith Packard
parent 120eced9ef
commit 3bcf603f6d
2 changed files with 9 additions and 0 deletions

View File

@ -3072,6 +3072,11 @@
#define TRANS_6BPC (2<<5)
#define TRANS_12BPC (3<<5)
#define _TRANSA_CHICKEN2 0xf0064
#define _TRANSB_CHICKEN2 0xf1064
#define TRANS_CHICKEN2(pipe) _PIPE(pipe, _TRANSA_CHICKEN2, _TRANSB_CHICKEN2)
#define TRANS_AUTOTRAIN_GEN_STALL_DIS (1<<31)
#define SOUTH_CHICKEN2 0xc2004
#define DPLS_EDP_PPS_FIX_DIS (1<<0)

View File

@ -7524,6 +7524,7 @@ static void ibx_init_clock_gating(struct drm_device *dev)
static void cpt_init_clock_gating(struct drm_device *dev)
{
struct drm_i915_private *dev_priv = dev->dev_private;
int pipe;
/*
* On Ibex Peak and Cougar Point, we need to disable clock
@ -7533,6 +7534,9 @@ static void cpt_init_clock_gating(struct drm_device *dev)
I915_WRITE(SOUTH_DSPCLK_GATE_D, PCH_DPLSUNIT_CLOCK_GATE_DISABLE);
I915_WRITE(SOUTH_CHICKEN2, I915_READ(SOUTH_CHICKEN2) |
DPLS_EDP_PPS_FIX_DIS);
/* Without this, mode sets may fail silently on FDI */
for_each_pipe(pipe)
I915_WRITE(TRANS_CHICKEN2(pipe), TRANS_AUTOTRAIN_GEN_STALL_DIS);
}
static void ironlake_teardown_rc6(struct drm_device *dev)