From 30414f3010aff95ffdb6bed7b9dce62cde94fdc7 Mon Sep 17 00:00:00 2001
From: Lucas De Marchi <lucas.demarchi@intel.com>
Date: Tue, 2 Jan 2018 12:18:37 -0800
Subject: [PATCH] drm/i915: Apply Display WA #1183 on skl, kbl, and cfl
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Git-commit: 30414f3010aff95ffdb6bed7b9dce62cde94fdc7
Patch-mainline: v4.15-rc7
References: FATE#322643 bsc#1055900
No-fix: 53421c2fe99ce16838639ad89d772d914a119a49
Display WA #1183 was recently added to workaround
"Failures when enabling DPLL0 with eDP link rate 2.16
or 4.32 GHz and CD clock frequency 308.57 or 617.14 MHz
(CDCLK_CTL CD Frequency Select 10b or 11b) used in this
enabling or in previous enabling."
This workaround was designed to minimize the impact only
to save the bad case with that link rates. But HW engineers
indicated that it should be safe to apply broadly, although
they were expecting the DPLL0 link rate to be unchanged on
runtime.
We need to cover 2 cases: when we are in fact enabling DPLL0
and when we are just changing the frequency with small
differences.
This is based on previous patch by Rodrigo Vivi with suggestions
from Ville Syrjälä.
Cc: Arthur J Runyan <arthur.j.runyan@intel.com>
Cc: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com>
Reviewed-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171204232210.4958-1-lucas.demarchi@intel.com
(cherry picked from commit 53421c2fe99ce16838639ad89d772d914a119a49)
[ Lucas: Backport to 4.15 adding back variable that has been removed on
commits not meant to be backported ]
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20180102201837.6812-1-lucas.demarchi@intel.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/i915_reg.h | 2 +
drivers/gpu/drm/i915/intel_cdclk.c | 35 +++++++++++++++++++++++---------
drivers/gpu/drm/i915/intel_runtime_pm.c | 10 +++++++++
3 files changed, 38 insertions(+), 9 deletions(-)
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -6977,6 +6977,7 @@ enum {
#define RESET_PCH_HANDSHAKE_ENABLE (1<<4)
#define GEN8_CHICKEN_DCPR_1 _MMIO(0x46430)
+#define SKL_SELECT_ALTERNATE_DC_EXIT (1<<30)
#define MASK_WAKEMEM (1<<13)
#define SKL_DFSM _MMIO(0x51000)
@@ -8522,6 +8523,7 @@ enum skl_power_gate {
#define BXT_CDCLK_CD2X_DIV_SEL_2 (2<<22)
#define BXT_CDCLK_CD2X_DIV_SEL_4 (3<<22)
#define BXT_CDCLK_CD2X_PIPE(pipe) ((pipe)<<20)
+#define CDCLK_DIVMUX_CD_OVERRIDE (1<<19)
#define BXT_CDCLK_CD2X_PIPE_NONE BXT_CDCLK_CD2X_PIPE(3)
#define BXT_CDCLK_SSA_PRECHARGE_ENABLE (1<<16)
#define CDCLK_FREQ_DECIMAL_MASK (0x7ff)
--- a/drivers/gpu/drm/i915/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/intel_cdclk.c
@@ -860,16 +860,10 @@ static void skl_set_preferred_cdclk_vco(
static void skl_dpll0_enable(struct drm_i915_private *dev_priv, int vco)
{
- int min_cdclk = skl_calc_cdclk(0, vco);
u32 val;
WARN_ON(vco != 8100000 && vco != 8640000);
- /* select the minimum CDCLK before enabling DPLL 0 */
- val = CDCLK_FREQ_337_308 | skl_cdclk_decimal(min_cdclk);
- I915_WRITE(CDCLK_CTL, val);
- POSTING_READ(CDCLK_CTL);
-
/*
* We always enable DPLL0 with the lowest link rate possible, but still
* taking into account the VCO required to operate the eDP panel at the
@@ -923,7 +917,7 @@ static void skl_set_cdclk(struct drm_i91
{
int cdclk = cdclk_state->cdclk;
int vco = cdclk_state->vco;
- u32 freq_select, pcu_ack;
+ u32 freq_select, pcu_ack, cdclk_ctl;
int ret;
WARN_ON((cdclk == 24000) != (vco == 0));
@@ -940,7 +934,7 @@ static void skl_set_cdclk(struct drm_i91
return;
}
- /* set CDCLK_CTL */
+ /* Choose frequency for this cdclk */
switch (cdclk) {
case 450000:
case 432000:
@@ -968,10 +962,33 @@ static void skl_set_cdclk(struct drm_i91
dev_priv->cdclk.hw.vco != vco)
skl_dpll0_disable(dev_priv);
+ cdclk_ctl = I915_READ(CDCLK_CTL);
+
+ if (dev_priv->cdclk.hw.vco != vco) {
+ /* Wa Display #1183: skl,kbl,cfl */
+ cdclk_ctl &= ~(CDCLK_FREQ_SEL_MASK | CDCLK_FREQ_DECIMAL_MASK);
+ cdclk_ctl |= freq_select | skl_cdclk_decimal(cdclk);
+ I915_WRITE(CDCLK_CTL, cdclk_ctl);
+ }
+
+ /* Wa Display #1183: skl,kbl,cfl */
+ cdclk_ctl |= CDCLK_DIVMUX_CD_OVERRIDE;
+ I915_WRITE(CDCLK_CTL, cdclk_ctl);
+ POSTING_READ(CDCLK_CTL);
+
if (dev_priv->cdclk.hw.vco != vco)
skl_dpll0_enable(dev_priv, vco);
- I915_WRITE(CDCLK_CTL, freq_select | skl_cdclk_decimal(cdclk));
+ /* Wa Display #1183: skl,kbl,cfl */
+ cdclk_ctl &= ~(CDCLK_FREQ_SEL_MASK | CDCLK_FREQ_DECIMAL_MASK);
+ I915_WRITE(CDCLK_CTL, cdclk_ctl);
+
+ cdclk_ctl |= freq_select | skl_cdclk_decimal(cdclk);
+ I915_WRITE(CDCLK_CTL, cdclk_ctl);
+
+ /* Wa Display #1183: skl,kbl,cfl */
+ cdclk_ctl &= ~CDCLK_DIVMUX_CD_OVERRIDE;
+ I915_WRITE(CDCLK_CTL, cdclk_ctl);
POSTING_READ(CDCLK_CTL);
/* inform PCU of the change */
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -598,6 +598,11 @@ void gen9_enable_dc5(struct drm_i915_pri
DRM_DEBUG_KMS("Enabling DC5\n");
+ /* Wa Display #1183: skl,kbl,cfl */
+ if (IS_GEN9_BC(dev_priv))
+ I915_WRITE(GEN8_CHICKEN_DCPR_1, I915_READ(GEN8_CHICKEN_DCPR_1) |
+ SKL_SELECT_ALTERNATE_DC_EXIT);
+
gen9_set_dc_state(dev_priv, DC_STATE_EN_UPTO_DC5);
}
@@ -625,6 +630,11 @@ void skl_disable_dc6(struct drm_i915_pri
{
DRM_DEBUG_KMS("Disabling DC6\n");
+ /* Wa Display #1183: skl,kbl,cfl */
+ if (IS_GEN9_BC(dev_priv))
+ I915_WRITE(GEN8_CHICKEN_DCPR_1, I915_READ(GEN8_CHICKEN_DCPR_1) |
+ SKL_SELECT_ALTERNATE_DC_EXIT);
+
gen9_set_dc_state(dev_priv, DC_STATE_DISABLE);
}