From e09a3036412a959689bacf017bf2cbc226c9fea4 Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Tue, 11 Apr 2017 11:13:39 +0100 Subject: [PATCH] drm/i915: Use __intel_uncore_wait_for_register_fw for sandybride_pcode_read 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 Cc: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20170411101340.31994-4-chris@chris-wilson.co.uk Reviewed-by: Tvrtko Ursulin --- drivers/gpu/drm/i915/intel_pm.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) diff --git a/drivers/gpu/drm/i915/intel_pm.c b/drivers/gpu/drm/i915/intel_pm.c index 55e1e88cd361..cacb65fa2dd5 100644 --- a/drivers/gpu/drm/i915/intel_pm.c +++ b/drivers/gpu/drm/i915/intel_pm.c @@ -8135,9 +8135,9 @@ int sandybridge_pcode_read(struct drm_i915_private *dev_priv, u32 mbox, u32 *val 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; } @@ -8180,9 +8180,9 @@ int sandybridge_pcode_write(struct drm_i915_private *dev_priv, 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; } -- 2.11.0