From c4298d15778bf21eb4834768f04c0dcf7975dec2 Mon Sep 17 00:00:00 2001
From: =?utf8?q?Jos=C3=A9=20Roberto=20de=20Souza?= <jose.souza@intel.com>
Date: Wed, 1 Mar 2023 12:10:53 -0800
Subject: [PATCH] drm/i915/display/mtl: Program latch to phy reset
MIME-Version: 1.0
Content-Type: text/plain; charset=utf8
Content-Transfer-Encoding: 8bit
Latch reset of phys during DC9 and when driver is unloaded to avoid
phy reset.
Specification ask us to program it closer to the step that enables
DC9 in DC_STATE_EN but doing this way allow us to sanitize the phy
latch during driver load.
BSpec: 49197
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Signed-off-by: José Roberto de Souza <jose.souza@intel.com>
Signed-off-by: Radhakrishna Sripada <radhakrishna.sripada@intel.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230301201053.928709-6-radhakrishna.sripada@intel.com
---
drivers/gpu/drm/i915/display/intel_display_power.c | 8 ++++++++
drivers/gpu/drm/i915/i915_reg.h | 2 ++
2 files changed, 10 insertions(+)
diff --git a/drivers/gpu/drm/i915/display/intel_display_power.c b/drivers/gpu/drm/i915/display/intel_display_power.c
index f085ae9711508..f86060195987c 100644
--- a/drivers/gpu/drm/i915/display/intel_display_power.c
+++ b/drivers/gpu/drm/i915/display/intel_display_power.c
@@ -1625,6 +1625,10 @@ static void icl_display_core_init(struct drm_i915_private *dev_priv,
intel_power_well_enable(dev_priv, well);
mutex_unlock(&power_domains->lock);
+ if (DISPLAY_VER(dev_priv) == 14)
+ intel_de_rmw(dev_priv, DC_STATE_EN,
+ HOLD_PHY_PG1_LATCH | HOLD_PHY_CLKREQ_PG1_LATCH, 0);
+
/* 4. Enable CDCLK. */
intel_cdclk_init_hw(dev_priv);
@@ -1678,6 +1682,10 @@ static void icl_display_core_uninit(struct drm_i915_private *dev_priv)
/* 3. Disable CD clock */
intel_cdclk_uninit_hw(dev_priv);
+ if (DISPLAY_VER(dev_priv) == 14)
+ intel_de_rmw(dev_priv, DC_STATE_EN, 0,
+ HOLD_PHY_PG1_LATCH | HOLD_PHY_CLKREQ_PG1_LATCH);
+
/*
* 4. Disable Power Well 1 (PG1).
* The AUX IO power wells are toggled on demand, so they are already
diff --git a/drivers/gpu/drm/i915/i915_reg.h b/drivers/gpu/drm/i915/i915_reg.h
index 9c30d292547d3..0ae084a8f7721 100644
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -7243,6 +7243,8 @@ enum skl_power_gate {
#define DC_STATE_DISABLE 0
#define DC_STATE_EN_DC3CO REG_BIT(30)
#define DC_STATE_DC3CO_STATUS REG_BIT(29)
+#define HOLD_PHY_CLKREQ_PG1_LATCH REG_BIT(21)
+#define HOLD_PHY_PG1_LATCH REG_BIT(20)
#define DC_STATE_EN_UPTO_DC5 (1 << 0)
#define DC_STATE_EN_DC9 (1 << 3)
#define DC_STATE_EN_UPTO_DC6 (2 << 0)
--
2.30.2