From 15a43cbf4736a3932e6259fa7d6e47558f6222b0 Mon Sep 17 00:00:00 2001 From: Nicholas Mc Guire Date: Fri, 16 Dec 2016 02:59:38 +0100 Subject: [PATCH] drm/i915: relax uncritical udelay_range() udelay_range(1, 2) is inefficient and as discussions with Jani Nikula unnecessary here. This replaces this tight setting with a relaxed delay of min=20 and max=50 which helps the hrtimer subsystem optimize timer handling. Fixes: commit be4fc046bed3 ("drm/i915: add VLV DSI PLL Calculations") Link: http://lkml.org/lkml/2016/12/15/147 Signed-off-by: Nicholas Mc Guire Reviewed-by: Jani Nikula Signed-off-by: Jani Nikula Link: http://patchwork.freedesktop.org/patch/msgid/1481853578-19834-1-git-send-email-hofrat@osadl.org --- drivers/gpu/drm/i915/intel_dsi_pll.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_dsi_pll.c b/drivers/gpu/drm/i915/intel_dsi_pll.c index cf8c1b0c30d6..61440e5c2563 100644 --- a/drivers/gpu/drm/i915/intel_dsi_pll.c +++ b/drivers/gpu/drm/i915/intel_dsi_pll.c @@ -156,8 +156,10 @@ static void vlv_enable_dsi_pll(struct intel_encoder *encoder, vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, config->dsi_pll.ctrl & ~DSI_PLL_VCO_EN); - /* wait at least 0.5 us after ungating before enabling VCO */ - usleep_range(1, 10); + /* wait at least 0.5 us after ungating before enabling VCO, + * allow hrtimer subsystem optimization by relaxing timing + */ + usleep_range(10, 50); vlv_cck_write(dev_priv, CCK_REG_DSI_PLL_CONTROL, config->dsi_pll.ctrl); -- 2.39.5