From 01ab0f9216070f3337b3da8953a259072f5bd4f7 Mon Sep 17 00:00:00 2001
From: Rafael Antognolli <rafael.antognolli@intel.com>
Date: Fri, 15 Dec 2017 16:11:16 -0800
Subject: [PATCH] drm/i915: Implement WaDisableVFclkgate.
Git-commit: 01ab0f9216070f3337b3da8953a259072f5bd4f7
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900
This workaround supposedly fixes some hangs in the VF unit.
Signed-off-by: Rafael Antognolli <rafael.antognolli@intel.com>
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171216001117.14232-1-rafael.antognolli@intel.com
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/i915_reg.h | 3 +++
drivers/gpu/drm/i915/intel_pm.c | 5 +++++
2 files changed, 8 insertions(+)
--- a/drivers/gpu/drm/i915/i915_reg.h
+++ b/drivers/gpu/drm/i915/i915_reg.h
@@ -3875,6 +3875,9 @@ enum {
#define SARBUNIT_CLKGATE_DIS (1 << 5)
#define RCCUNIT_CLKGATE_DIS (1 << 7)
+#define UNSLICE_UNIT_LEVEL_CLKGATE _MMIO(0x9434)
+#define VFUNIT_CLKGATE_DIS (1 << 20)
+
/*
* Display engine regs
*/
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -8447,6 +8447,11 @@ static void cnl_init_clock_gating(struct
if (IS_CNL_REVID(dev_priv, CNL_REVID_A0, CNL_REVID_B0))
val |= SARBUNIT_CLKGATE_DIS;
I915_WRITE(SLICE_UNIT_LEVEL_CLKGATE, val);
+
+ /* WaDisableVFclkgate:cnl */
+ val = I915_READ(UNSLICE_UNIT_LEVEL_CLKGATE);
+ val |= VFUNIT_CLKGATE_DIS;
+ I915_WRITE(UNSLICE_UNIT_LEVEL_CLKGATE, val);
}
static void cfl_init_clock_gating(struct drm_i915_private *dev_priv)