redonkable/alistair23-linux
redonkable/alistair23-linux
1
0
Fork 0
Code Releases Activity

drm/i915: fix to setup display reference clock control on Ironlake

Browse source 
For new stepping of PCH, the display reference clock
is fully under driver's control. This one trys to setup
all needed reference clock for different outputs. Older
stepping of PCH chipset should be ignoring this.

This fixes output failure issue on newer PCH which requires
driver to take control of reference clock enabling.

Cc: Stable Team <stable@kernel.org>
Signed-off-by: Zhenyu Wang <zhenyuw@linux.intel.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
This commit is contained in:
Zhenyu Wang 2009-10-19 15:43:48 +08:00 committed by Eric Anholt
parent 0d9c778978
commit c038e51e84
2 changed files with 42 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
drivers/gpu/drm/i915/i915_reg.h
View file

@ -2158,11 +2158,11 @@
#define DREF_CPU_SOURCE_OUTPUT_MASK (3<<13)
#define DREF_SSC_SOURCE_DISABLE (0<<11)
#define DREF_SSC_SOURCE_ENABLE (2<<11)
#define DREF_SSC_SOURCE_MASK (2<<11)
#define DREF_SSC_SOURCE_MASK (3<<11)
#define DREF_NONSPREAD_SOURCE_DISABLE (0<<9)
#define DREF_NONSPREAD_CK505_ENABLE (1<<9)
#define DREF_NONSPREAD_SOURCE_ENABLE (2<<9)
#define DREF_NONSPREAD_SOURCE_MASK (2<<9)
#define DREF_NONSPREAD_SOURCE_MASK (3<<9)
#define DREF_SUPERSPREAD_SOURCE_DISABLE (0<<7)
#define DREF_SUPERSPREAD_SOURCE_ENABLE (2<<7)
#define DREF_SSC4_DOWNSPREAD (0<<6)

40
drivers/gpu/drm/i915/intel_display.c
View file

@ -2814,6 +2814,46 @@ static int intel_crtc_mode_set(struct drm_crtc *crtc,
link_bw, &m_n);
}
/* Ironlake: try to setup display ref clock before DPLL
* enabling. This is only under driver's control after
* PCH B stepping, previous chipset stepping should be
* ignoring this setting.
*/
if (IS_IGDNG(dev)) {
temp = I915_READ(PCH_DREF_CONTROL);
/* Always enable nonspread source */
temp &= ~DREF_NONSPREAD_SOURCE_MASK;
temp |= DREF_NONSPREAD_SOURCE_ENABLE;
I915_WRITE(PCH_DREF_CONTROL, temp);
POSTING_READ(PCH_DREF_CONTROL);
temp &= ~DREF_SSC_SOURCE_MASK;
temp |= DREF_SSC_SOURCE_ENABLE;
I915_WRITE(PCH_DREF_CONTROL, temp);
POSTING_READ(PCH_DREF_CONTROL);
udelay(200);
if (is_edp) {
if (dev_priv->lvds_use_ssc) {
temp |= DREF_SSC1_ENABLE;
I915_WRITE(PCH_DREF_CONTROL, temp);
POSTING_READ(PCH_DREF_CONTROL);
udelay(200);
temp &= ~DREF_CPU_SOURCE_OUTPUT_MASK;
temp |= DREF_CPU_SOURCE_OUTPUT_DOWNSPREAD;
I915_WRITE(PCH_DREF_CONTROL, temp);
POSTING_READ(PCH_DREF_CONTROL);
} else {
temp |= DREF_CPU_SOURCE_OUTPUT_NONSPREAD;
I915_WRITE(PCH_DREF_CONTROL, temp);
POSTING_READ(PCH_DREF_CONTROL);
}
}
}
if (IS_IGD(dev)) {
fp = (1 << clock.n) << 16 | clock.m1 << 8 | clock.m2;
if (has_reduced_clock)