2.6.31-stable review patch. If anyone has any objections, please let us know. ------------------ From: Zhenyu Wang commit c038e51e841581cc3fb9a76e5e16331331e9c85c upstream. 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. Signed-off-by: Zhenyu Wang Signed-off-by: Eric Anholt Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/i915_reg.h | 4 +-- drivers/gpu/drm/i915/intel_display.c | 40 +++++++++++++++++++++++++++++++++++ 2 files changed, 42 insertions(+), 2 deletions(-) --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -1990,11 +1990,11 @@ #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) --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -2442,6 +2442,46 @@ static int intel_crtc_mode_set(struct dr 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; else -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/