From 738a8143866c4cdbe4c008f1583a0c55338266b2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Ville=20Syrj=C3=A4l=C3=A4?= <ville.syrjala@linux.intel.com>
Date: Wed, 15 Nov 2017 22:04:42 +0200
Subject: [PATCH] drm/i915: Don't sanitize frame start delay if the pipe is off
Mime-version: 1.0
Content-type: text/plain; charset=UTF-8
Content-transfer-encoding: 8bit
Git-commit: 738a8143866c4cdbe4c008f1583a0c55338266b2
Patch-mainline: v4.16-rc1
References: FATE#322643 bsc#1055900
Avoid touching PIPECONF in intel_sanitize_crtc() unless the pipe is
actually on. Should cure some unclaimed register accesses during reset,
as we are rather cavalier in our approach to powerdomain management.
We don't have to sanitize this if the pipe is off since we will
overwrite the frame start delay anyway when turning the pipe on.
V2: Amended commit message to implicate the reset path (Chris)
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=102249
Signed-off-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20171115200442.15051-1-ville.syrjala@linux.intel.com
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/intel_display.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/gpu/drm/i915/intel_display.c
+++ b/drivers/gpu/drm/i915/intel_display.c
@@ -14868,7 +14868,7 @@ static void intel_sanitize_crtc(struct i
enum transcoder cpu_transcoder = crtc->config->cpu_transcoder;
/* Clear any frame start delays used for debugging left by the BIOS */
- if (!transcoder_is_dsi(cpu_transcoder)) {
+ if (crtc->active && !transcoder_is_dsi(cpu_transcoder)) {
i915_reg_t reg = PIPECONF(cpu_transcoder);
I915_WRITE(reg,