linux-kernel - [PATCH 0/7] Minor DP aux transaction fixes

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Date:	Fri,  5 Aug 2016 20:30:32 -0400
From:	Lyude <cpaul@...hat.com>
To:	dri-devel@...ts.freedesktop.org, amd-gfx@...ts.freedesktop.org,
	xorg-driver-ati@...ts.freedesktop.org
Cc:	Lyude <cpaul@...hat.com>, David Airlie <airlied@...ux.ie>,
	linux-kernel@...r.kernel.org,
	Alex Deucher <alexander.deucher@....com>,
	Christian König <christian.koenig@....com>,
	Tom St Denis <tom.stdenis@....com>,
	Jammy Zhou <Jammy.Zhou@....com>,
	Ken Wang <Qingqing.Wang@....com>
Subject: [PATCH 0/7] Minor DP aux transaction fixes

While I was investigating an unrelated bug on the radeon driver, I noticed that
it's become rather difficult to actually read through dmesg with drm.debug
turned on, on account of the huge number of messages we end up printing from
failed DP aux transactions that happen every time we reprobe each connector.

Timed out transactions are relatively normal, and as well there's a lot of
places in radeon/amdgpu where we're printing redundant debugging information
dozens of times each time we attempt a DP aux transactions.

Additionally, I've removed some of the retry loops in amdgpu/radeon. These were
definitely useful at one point, but since we now retry any failed aux
transaction unconditionally in DRM's dp helpers they don't serve much purpose
other then to make failing aux transactions take a lot more time then they need
to.

Lyude (7):
  drm/dp_helper: Print first error received on failure in
    drm_dp_dpcd_access()
  drm/radeon: Don't print error on aux transaction timeouts
  drm/radeon: Don't retry 7 times in radeon_dp_dpcd()
  drm/amdgpu: Don't print error on aux transaction timeouts
  drm/amdgpu: Don't retry 7 times in amdgpu_atombios_dp_get_dpcd()
  drm: Add ratelimited versions of the DRM_DEBUG* macros
  drm/dp_helper: Rate limit timeout errors from drm_dp_i2c_do_msg()

 drivers/gpu/drm/amd/amdgpu/atombios_dp.c | 22 ++++++++++------------
 drivers/gpu/drm/drm_dp_helper.c          | 14 ++++++++++++--
 drivers/gpu/drm/radeon/atombios_dp.c     | 21 ++++++++++-----------
 drivers/gpu/drm/radeon/radeon_dp_auxch.c |  1 -
 include/drm/drmP.h                       | 30 ++++++++++++++++++++++++++++++
 5 files changed, 62 insertions(+), 26 deletions(-)

-- 
2.7.4