From 78cfa580f81e69857815c59c8908aee454726da1 Mon Sep 17 00:00:00 2001 From: "Pandiyan, Dhinakaran" Date: Tue, 7 Mar 2017 16:12:51 -0800 Subject: [PATCH] drm/i915/glk: Apply cdclk workaround for DP audio Implement the DP-Audio cdclk restriction for GLK, similar to what is implemented for BDW and other GEN9 platforms. The max. pixel clock adjustment for GLK, however factors in the 2 pixels per clock output that GLK generates. Separating min. cdclk and max. pixel_rate would be nicer, but let's defer that to future and fix the GLK bug for now. Signed-off-by: Dhinakaran Pandiyan Reviewed-by: Paulo Zanoni Signed-off-by: Paulo Zanoni Link: http://patchwork.freedesktop.org/patch/msgid/1488931972-2865-1-git-send-email-dhinakaran.pandiyan@intel.com --- drivers/gpu/drm/i915/intel_cdclk.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c index c2cc33f3d888..dd350642eba1 100644 --- a/drivers/gpu/drm/i915/intel_cdclk.c +++ b/drivers/gpu/drm/i915/intel_cdclk.c @@ -1442,16 +1442,21 @@ static int bdw_adjust_min_pipe_pixel_rate(struct intel_crtc_state *crtc_state, if (IS_BROADWELL(dev_priv) && crtc_state->ips_enabled) pixel_rate = DIV_ROUND_UP(pixel_rate * 100, 95); - /* BSpec says "Do not use DisplayPort with CDCLK less than - * 432 MHz, audio enabled, port width x4, and link rate - * HBR2 (5.4 GHz), or else there may be audio corruption or - * screen corruption." + /* BSpec says "Do not use DisplayPort with CDCLK less than 432 MHz, + * audio enabled, port width x4, and link rate HBR2 (5.4 GHz), or else + * there may be audio corruption or screen corruption." This cdclk + * restriction for GLK is 316.8 MHz and since GLK can output two + * pixels per clock, the pixel rate becomes 2 * 316.8 MHz. */ if (intel_crtc_has_dp_encoder(crtc_state) && crtc_state->has_audio && crtc_state->port_clock >= 540000 && - crtc_state->lane_count == 4) - pixel_rate = max(432000, pixel_rate); + crtc_state->lane_count == 4) { + if (IS_GEMINILAKE(dev_priv)) + pixel_rate = max(2 * 316800, pixel_rate); + else + pixel_rate = max(432000, pixel_rate); + } return pixel_rate; } -- 2.20.1