From 991344678778f93a7a7dfb0f70c2d69a1c1d42d9 Mon Sep 17 00:00:00 2001 From: Gabriel Krisman Bertazi Date: Wed, 28 Jun 2017 18:06:05 -0300 Subject: [PATCH] drm/i915: reintroduce VLV/CHV PFI programming power domain workaround MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit commit 9c75b185274b7766fe69c2e73607c1ed780b284b upstream. There are still cases on these platforms where an attempt is made to configure the CDCLK while the power domain is off, like when coming back from a suspend. So the workaround below is still needed. This effectively reverts commit 63ff30442519 ("drm/i915: Nuke the VLV/CHV PFI programming power domain workaround"). Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=101517 Suggested-by: Ville Syrjälä Signed-off-by: Gabriel Krisman Bertazi Link: http://patchwork.freedesktop.org/patch/msgid/20170628210605.4994-1-krisman@collabora.co.uk Reviewed-by: Ville Syrjälä Signed-off-by: Ville Syrjälä (cherry picked from commit 886015a0ad43c7fc034b23ea4614ba39162f9ddd) Signed-off-by: Jani Nikula Signed-off-by: Greg Kroah-Hartman --- drivers/gpu/drm/i915/intel_cdclk.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c index f29a226e24d88..6808f82ffb5d1 100644 --- a/drivers/gpu/drm/i915/intel_cdclk.c +++ b/drivers/gpu/drm/i915/intel_cdclk.c @@ -491,6 +491,14 @@ static void vlv_set_cdclk(struct drm_i915_private *dev_priv, int cdclk = cdclk_state->cdclk; u32 val, cmd; + /* There are cases where we can end up here with power domains + * off and a CDCLK frequency other than the minimum, like when + * issuing a modeset without actually changing any display after + * a system suspend. So grab the PIPE-A domain, which covers + * the HW blocks needed for the following programming. + */ + intel_display_power_get(dev_priv, POWER_DOMAIN_PIPE_A); + if (cdclk >= 320000) /* jump to highest voltage for 400MHz too */ cmd = 2; else if (cdclk == 266667) @@ -549,6 +557,8 @@ static void vlv_set_cdclk(struct drm_i915_private *dev_priv, intel_update_cdclk(dev_priv); vlv_program_pfi_credits(dev_priv); + + intel_display_power_put(dev_priv, POWER_DOMAIN_PIPE_A); } static void chv_set_cdclk(struct drm_i915_private *dev_priv, @@ -568,6 +578,14 @@ static void chv_set_cdclk(struct drm_i915_private *dev_priv, return; } + /* There are cases where we can end up here with power domains + * off and a CDCLK frequency other than the minimum, like when + * issuing a modeset without actually changing any display after + * a system suspend. So grab the PIPE-A domain, which covers + * the HW blocks needed for the following programming. + */ + intel_display_power_get(dev_priv, POWER_DOMAIN_PIPE_A); + /* * Specs are full of misinformation, but testing on actual * hardware has shown that we just need to write the desired @@ -590,6 +608,8 @@ static void chv_set_cdclk(struct drm_i915_private *dev_priv, intel_update_cdclk(dev_priv); vlv_program_pfi_credits(dev_priv); + + intel_display_power_put(dev_priv, POWER_DOMAIN_PIPE_A); } static int bdw_calc_cdclk(int max_pixclk) -- 2.47.2