This reverts commit 1a738347.

It caused at least some Kaveri laptops to incorrectly report DisplayPort
connectors as connected.

Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=97857
Cc: stable@vger.kernel.org
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NMichel Dänzer <michel.daenzer@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

Since it's normal for DRM to retry our aux transaction helpers multiple
times in a row, up to 32 times for each attempted transaction, we're
making a lot of noise that is no longer necessary now that DRM will just
print the return code we give it.
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NLyude <cpaul@redhat.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>

There is an issue observed when we hotplug a second DP
4K monitor to the system. Sometimes, the link training
fails for the second monitor after HPD interrupt
generation.

The issue happens when some queued or deferred transactions
are already present on the AUX channel when we initiate
a new transcation to (say) get DPCD or during link training.

We set AUX_IGNORE_HPD_DISCON bit in the AUX_CONTROL
register so that we can ignore any such deferred
transactions when a new AUX transaction is initiated.
Signed-off-by: NArindam Nath <arindam.nath@amd.com>
Reviewed-by: NAlex Deucher <alexander.deucher@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

AUX addresses are 20 bits long. Send out the entire address instead of
just the low 16 bits.

Port of:
drm/radeon/atom: Send out the full AUX address
to radeon non-atom aux path
Reviewed-by: NChristian König <christian.koenig@amd.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

That atom table does not check these bits.  Fixes aux
regressions on some boards.
Reported-by: NMalte Schröder <malte@tnxip.de>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

The atombios tables have an unfortunate restriction on only
being able to write 12 bytes, MST really wants 16-bytes here,
and since the hw can do it, we should just write directly to it.

This uses a module option to allow for it now, and maybe
we should provide the old code as a fallback for a while.

v2: (agd5f)
- move registers to a proper register header
- only enable on DCE5+
- enable by default on DCE5+
- Switch pad to aux mode before using it
- reformat instance handling to better match the
  rest of the driver
Signed-off-by: NDave Airlie <airlied@redhat.com>
Signed-off-by: NAlex Deucher <alexander.deucher@amd.com>