The patch below does not apply to the 4.14-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 9d219554d9bf59875b4e571a0392d620e8954879 Mon Sep 17 00:00:00 2001

From: Rodrigo Vivi rodrigo.vivi@intel.com Date: Wed, 2 May 2018 10:52:55 -0700 Subject: [PATCH] drm/i915: Adjust eDP's logical vco in a reliable place. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit

On intel_dp_compute_config() we were calculating the needed vco for eDP on gen9 and we stashing it in intel_atomic_state.cdclk.logical.vco

However few moments later on intel_modeset_checks() we fully replace entire intel_atomic_state.cdclk.logical with dev_priv->cdclk.logical fully overwriting the logical desired vco for eDP on gen9.

So, with wrong VCO value we end up with wrong desired cdclk, but also it will raise a lot of WARNs: On gen9, when we read CDCLK_CTL to verify if we configured properly the desired frequency the CD Frequency Select bits [27:26] == 10b can mean 337.5 or 308.57 MHz depending on the VCO. So if we have wrong VCO value stashed we will believe the frequency selection didn't stick and start to raise WARNs of cdclk mismatch.

[ 42.857519] [drm:intel_dump_cdclk_state [i915]] Changing CDCLK to 308571 kHz, VCO 8640000 kHz, ref 24000 kHz, bypass 24000 kHz, voltage level 0 [ 42.897269] cdclk state doesn't match! [ 42.901052] WARNING: CPU: 5 PID: 1116 at drivers/gpu/drm/i915/intel_cdclk.c:2084 intel_set_cdclk+0x5d/0x110 [i915] [ 42.938004] RIP: 0010:intel_set_cdclk+0x5d/0x110 [i915] [ 43.155253] WARNING: CPU: 5 PID: 1116 at drivers/gpu/drm/i915/intel_cdclk.c:2084 intel_set_cdclk+0x5d/0x110 [i915] [ 43.170277] [drm:intel_dump_cdclk_state [i915]] [hw state] 337500 kHz, VCO 8100000 kHz, ref 24000 kHz, bypass 24000 kHz, voltage level 0 [ 43.182566] [drm:intel_dump_cdclk_state [i915]] [sw state] 308571 kHz, VCO 8640000 kHz, ref 24000 kHz, bypass 24000 kHz, voltage level 0

v2: Move the entire eDP's vco logical adjustment to inside the skl_modeset_calc_cdclk as suggested by Ville.

Cc: Ville Syrjälä ville.syrjala@linux.intel.com Signed-off-by: Rodrigo Vivi rodrigo.vivi@intel.com Reviewed-by: Ville Syrjälä ville.syrjala@linux.intel.com Fixes: bb0f4aab0e76 ("drm/i915: Track full cdclk state for the logical and actual cdclk frequencies") Cc: stable@vger.kernel.org # v4.12+ Link: https://patchwork.freedesktop.org/patch/msgid/20180502175255.5344-1-rodrigo.... (cherry picked from commit 3297234a05ab1e90091b0574db4c397ef0e90d5f) Signed-off-by: Joonas Lahtinen joonas.lahtinen@linux.intel.com

diff --git a/drivers/gpu/drm/i915/intel_cdclk.c b/drivers/gpu/drm/i915/intel_cdclk.c index 32d24c69da3c..704ddb4d3ca7 100644 --- a/drivers/gpu/drm/i915/intel_cdclk.c +++ b/drivers/gpu/drm/i915/intel_cdclk.c @@ -2302,9 +2302,44 @@ static int bdw_modeset_calc_cdclk(struct drm_atomic_state *state) return 0; }

+static int skl_dpll0_vco(struct intel_atomic_state *intel_state) +{ + struct drm_i915_private *dev_priv = to_i915(intel_state->base.dev); + struct intel_crtc *crtc; + struct intel_crtc_state *crtc_state; + int vco, i; + + vco = intel_state->cdclk.logical.vco; + if (!vco) + vco = dev_priv->skl_preferred_vco_freq; + + for_each_new_intel_crtc_in_state(intel_state, crtc, crtc_state, i) { + if (!crtc_state->base.enable) + continue; + + if (!intel_crtc_has_type(crtc_state, INTEL_OUTPUT_EDP)) + continue; + + /* + * DPLL0 VCO may need to be adjusted to get the correct + * clock for eDP. This will affect cdclk as well. + */ + switch (crtc_state->port_clock / 2) { + case 108000: + case 216000: + vco = 8640000; + break; + default: + vco = 8100000; + break; + } + } + + return vco; +} + static int skl_modeset_calc_cdclk(struct drm_atomic_state *state) { - struct drm_i915_private *dev_priv = to_i915(state->dev); struct intel_atomic_state *intel_state = to_intel_atomic_state(state); int min_cdclk, cdclk, vco;

@@ -2312,9 +2347,7 @@ static int skl_modeset_calc_cdclk(struct drm_atomic_state *state) if (min_cdclk < 0) return min_cdclk;

- vco = intel_state->cdclk.logical.vco; - if (!vco) - vco = dev_priv->skl_preferred_vco_freq; + vco = skl_dpll0_vco(intel_state);

/* * FIXME should also account for plane ratio diff --git a/drivers/gpu/drm/i915/intel_dp.c b/drivers/gpu/drm/i915/intel_dp.c index 9a4a51e79fa1..b7b4cfdeb974 100644 --- a/drivers/gpu/drm/i915/intel_dp.c +++ b/drivers/gpu/drm/i915/intel_dp.c @@ -1881,26 +1881,6 @@ intel_dp_compute_config(struct intel_encoder *encoder, reduce_m_n); }

- /* - * DPLL0 VCO may need to be adjusted to get the correct - * clock for eDP. This will affect cdclk as well. - */ - if (intel_dp_is_edp(intel_dp) && IS_GEN9_BC(dev_priv)) { - int vco; - - switch (pipe_config->port_clock / 2) { - case 108000: - case 216000: - vco = 8640000; - break; - default: - vco = 8100000; - break; - } - - to_intel_atomic_state(pipe_config->base.state)->cdclk.logical.vco = vco; - } - if (!HAS_DDI(dev_priv)) intel_dp_set_clock(encoder, pipe_config);