From e09a3036412a959689bacf017bf2cbc226c9fea4 Mon Sep 17 00:00:00 2001
From: Chris Wilson <chris@chris-wilson.co.uk>
Date: Tue, 11 Apr 2017 11:13:39 +0100
Subject: [PATCH] drm/i915: Use __intel_uncore_wait_for_register_fw for sandybride_pcode_read
Git-commit: e09a3036412a959689bacf017bf2cbc226c9fea4
Patch-mainline: v4.13-rc1
References: FATE#322643 bsc#1055900
Since the sandybridge_pcode_read() may be called from
skl_pcode_request() inside an atomic context (with preempt disabled), we
should avoid hitting any sleeping paths. Currently is being called with
a 500ms timeout, irrespective of being inside an atomic context or not.
This is reduced down to 500us to play nice with the atomic context, and
that appears to be sufficient to keep BAT happy (we have a DRM_ERROR
should it timeout), i.e. we do not see any 500us pcode timeouts for
normal use. So leave it as a pure spin without having to introduce new
code paths to separate atomic/normal contexts.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/20170411101340.31994-4-chris@chris-wilson.co.uk
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@intel.com>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/gpu/drm/i915/intel_pm.c | 12 ++++++------
1 file changed, 6 insertions(+), 6 deletions(-)
--- a/drivers/gpu/drm/i915/intel_pm.c
+++ b/drivers/gpu/drm/i915/intel_pm.c
@@ -8156,9 +8156,9 @@ int sandybridge_pcode_read(struct drm_i9
I915_WRITE_FW(GEN6_PCODE_DATA1, 0);
I915_WRITE_FW(GEN6_PCODE_MAILBOX, GEN6_PCODE_READY | mbox);
- if (intel_wait_for_register_fw(dev_priv,
- GEN6_PCODE_MAILBOX, GEN6_PCODE_READY, 0,
- 500)) {
+ if (__intel_wait_for_register_fw(dev_priv,
+ GEN6_PCODE_MAILBOX, GEN6_PCODE_READY, 0,
+ 500, 0, NULL)) {
DRM_ERROR("timeout waiting for pcode read (%d) to finish\n", mbox);
return -ETIMEDOUT;
}
@@ -8201,9 +8201,9 @@ int sandybridge_pcode_write(struct drm_i
I915_WRITE_FW(GEN6_PCODE_DATA1, 0);
I915_WRITE_FW(GEN6_PCODE_MAILBOX, GEN6_PCODE_READY | mbox);
- if (intel_wait_for_register_fw(dev_priv,
- GEN6_PCODE_MAILBOX, GEN6_PCODE_READY, 0,
- 500)) {
+ if (__intel_wait_for_register_fw(dev_priv,
+ GEN6_PCODE_MAILBOX, GEN6_PCODE_READY, 0,
+ 500, 0, NULL)) {
DRM_ERROR("timeout waiting for pcode write (%d) to finish\n", mbox);
return -ETIMEDOUT;
}