From a945ce7e4eeb9c629d8a75b78203b026f74c2ea2 Mon Sep 17 00:00:00 2001 From: Vijay Purushothaman Date: Thu, 5 Mar 2015 19:30:57 +0530 Subject: [PATCH] drm/i915: Disable M2 frac division for integer case v2 : Handle M2 frac division for both M2 frac and int cases v3 : Addressed Ville's review comments. Cleared the old bits for RMW v4 : Fix feedfwd gain (Ville) Signed-off-by: Vijay Purushothaman Reviewed-by: Ville Syrjala Signed-off-by: Daniel Vetter --- drivers/gpu/drm/i915/i915_reg.h | 1 + drivers/gpu/drm/i915/intel_display.c | 14 ++++++++++---- 2 files changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h index f700922bcb56..17b662f0849d 100644 --- a/drivers/gpu/drm/i915/i915_reg.h +++ b/drivers/gpu/drm/i915/i915_reg.h @@ -1029,6 +1029,7 @@ enum skl_disp_power_wells { #define DPIO_CHV_FIRST_MOD (0 << 8) #define DPIO_CHV_SECOND_MOD (1 << 8) #define DPIO_CHV_FEEDFWD_GAIN_SHIFT 0 +#define DPIO_CHV_FEEDFWD_GAIN_MASK (0xF << 0) #define CHV_PLL_DW3(ch) _PIPE(ch, _CHV_PLL_DW3_CH0, _CHV_PLL_DW3_CH1) #define _CHV_PLL_DW6_CH0 0x8018 diff --git a/drivers/gpu/drm/i915/intel_display.c b/drivers/gpu/drm/i915/intel_display.c index c3a58886b32f..8676cb8deaf8 100644 --- a/drivers/gpu/drm/i915/intel_display.c +++ b/drivers/gpu/drm/i915/intel_display.c @@ -6161,6 +6161,7 @@ static void chv_prepare_pll(struct intel_crtc *crtc, enum dpio_channel port = vlv_pipe_to_channel(pipe); u32 loopfilter, intcoeff; u32 bestn, bestm1, bestm2, bestp1, bestp2, bestm2_frac; + u32 dpio_val; int refclk; bestn = pipe_config->dpll.n; @@ -6169,6 +6170,7 @@ static void chv_prepare_pll(struct intel_crtc *crtc, bestm2 = pipe_config->dpll.m2 >> 22; bestp1 = pipe_config->dpll.p1; bestp2 = pipe_config->dpll.p2; + dpio_val = 0; /* * Enable Refclk and SSC @@ -6194,12 +6196,16 @@ static void chv_prepare_pll(struct intel_crtc *crtc, 1 << DPIO_CHV_N_DIV_SHIFT); /* M2 fraction division */ - vlv_dpio_write(dev_priv, pipe, CHV_PLL_DW2(port), bestm2_frac); + if (bestm2_frac) + vlv_dpio_write(dev_priv, pipe, CHV_PLL_DW2(port), bestm2_frac); /* M2 fraction division enable */ - vlv_dpio_write(dev_priv, pipe, CHV_PLL_DW3(port), - DPIO_CHV_FRAC_DIV_EN | - (2 << DPIO_CHV_FEEDFWD_GAIN_SHIFT)); + dpio_val = vlv_dpio_read(dev_priv, pipe, CHV_PLL_DW3(port)); + dpio_val &= ~(DPIO_CHV_FEEDFWD_GAIN_MASK | DPIO_CHV_FRAC_DIV_EN); + dpio_val |= (2 << DPIO_CHV_FEEDFWD_GAIN_SHIFT); + if (bestm2_frac) + dpio_val |= DPIO_CHV_FRAC_DIV_EN; + vlv_dpio_write(dev_priv, pipe, CHV_PLL_DW3(port), dpio_val); /* Loop filter */ refclk = i9xx_get_refclk(crtc, 0); -- 2.20.1