blob: 37230af4546cb53b0acfe6ae7f7b9c98adb59e05 [file] [log] [blame]
From d7b100c2dd78640f328447d9360bde06d65a737b Mon Sep 17 00:00:00 2001
From: Matt Roper <matthew.d.roper@intel.com>
Date: Thu, 27 Feb 2020 16:43:19 -0800
Subject: [PATCH] drm/i915: Program MBUS with rmw during initialization
commit c725161924f9a5872a3e53b73345a6026a5c170e upstream.
It wasn't terribly clear from the bspec's wording, but after discussion
with the hardware folks, it turns out that we need to preserve the
pre-existing contents of the MBUS ABOX control register when
initializing a few specific bits.
Bspec: 49213
Bspec: 50096
Fixes: 4cb4585e5a7f ("drm/i915/icl: initialize MBus during display init")
Cc: Stanislav Lisovskiy <stanislav.lisovskiy@intel.com>
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200204011032.582737-1-matthew.d.roper@intel.com
Reviewed-by: Matt Atwood <matthew.s.atwood@intel.com>
(cherry picked from commit 837b63e6087838d0f1e612d448405419199d8033)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200228004320.127142-1-matthew.d.roper@intel.com
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
diff --git a/drivers/gpu/drm/i915/intel_runtime_pm.c b/drivers/gpu/drm/i915/intel_runtime_pm.c
index 6150e35bf7b5..75af48d56614 100644
--- a/drivers/gpu/drm/i915/intel_runtime_pm.c
+++ b/drivers/gpu/drm/i915/intel_runtime_pm.c
@@ -3599,13 +3599,19 @@ static void icl_dbuf_disable(struct drm_i915_private *dev_priv)
static void icl_mbus_init(struct drm_i915_private *dev_priv)
{
- u32 val;
+ u32 mask, val;
- val = MBUS_ABOX_BT_CREDIT_POOL1(16) |
- MBUS_ABOX_BT_CREDIT_POOL2(16) |
- MBUS_ABOX_B_CREDIT(1) |
- MBUS_ABOX_BW_CREDIT(1);
+ mask = MBUS_ABOX_BT_CREDIT_POOL1_MASK |
+ MBUS_ABOX_BT_CREDIT_POOL2_MASK |
+ MBUS_ABOX_B_CREDIT_MASK |
+ MBUS_ABOX_BW_CREDIT_MASK;
+ val = I915_READ(MBUS_ABOX_CTL);
+ val &= ~mask;
+ val |= MBUS_ABOX_BT_CREDIT_POOL1(16) |
+ MBUS_ABOX_BT_CREDIT_POOL2(16) |
+ MBUS_ABOX_B_CREDIT(1) |
+ MBUS_ABOX_BW_CREDIT(1);
I915_WRITE(MBUS_ABOX_CTL, val);
}
--
2.7.4