From: Ville Syrjälä Date: Mon, 9 Dec 2013 16:54:13 +0000 (+0200) Subject: drm/i915: Extract p2 divider correctly for gen2 LVDS dual channel X-Git-Tag: firefly_0821_release~176^2~4523^2~44^2~25 X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=b1c560d13d1aab194b467ca33d0be6ca6e829ee5;p=firefly-linux-kernel-4.4.55.git drm/i915: Extract p2 divider correctly for gen2 LVDS dual channel In order to determine the correct p2 divider for LVDS on gen2, we need to check the CLKB mode from the LVDS port register to determine if we're dealing with single or dual channel LVDS. Cc: Bruno Prémont Signed-off-by: Ville Syrjälä Tested-by: Bruno Prémont Signed-off-by: Daniel Vetter --- diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index 7b1b18d8f45c..8c4e384b8ae1 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -7951,12 +7951,17 @@ static void i9xx_crtc_clock_get(struct intel_crtc *crtc, else i9xx_clock(refclk, &clock); } else { - bool is_lvds = (pipe == 1) && (I915_READ(LVDS) & LVDS_PORT_EN); + u32 lvds = I915_READ(LVDS); + bool is_lvds = (pipe == 1) && (lvds & LVDS_PORT_EN); if (is_lvds) { clock.p1 = ffs((dpll & DPLL_FPA01_P1_POST_DIV_MASK_I830_LVDS) >> DPLL_FPA01_P1_POST_DIV_SHIFT); - clock.p2 = 14; + + if (lvds & LVDS_CLKB_POWER_UP) + clock.p2 = 7; + else + clock.p2 = 14; } else { if (dpll & PLL_P1_DIVIDE_BY_TWO) clock.p1 = 2;