The host1x_bo_pin() and host1x_bo_unpin() APIs are used to pin and unpin
buffers during host1x job submission. Pinning currently returns the SG
table and the DMA address (an IOVA if an IOMMU is used or a physical
address if no IOMMU is used) of the buffer. The DMA address is only used
for buffers that are relocated, whereas the host1x driver will map
gather buffers into its own IOVA space so that they can be processed by
the CDMA engine.

This approach has a couple of issues. On one hand it's not very useful
to return a DMA address for the buffer if host1x doesn't need it. On the
other hand, returning the SG table of the buffer is suboptimal because a
single SG table cannot be shared for multiple mappings, because the DMA
address is stored within the SG table, and the DMA address may be
different for different devices.

Subsequent patches will move the host1x driver over to the DMA API which
doesn't work with a single shared SG table. Fix this by returning a new
SG table each time a buffer is pinned. This allows the buffer to be
referenced by multiple jobs for different engines.

Change the prototypes of host1x_bo_pin() and host1x_bo_unpin() to take a
struct device *, specifying the device for which the buffer should be
pinned. This is required in order to be able to properly construct the
SG table. While at it, make host1x_bo_pin() return the SG table because
that allows us to return an ERR_PTR()-encoded error code if we need to,
or return NULL to signal that we don't need the SG table to be remapped
and can simply use the DMA address as-is. At the same time, returning
the DMA address is made optional because in the example of command
buffers, host1x doesn't need to know the DMA address since it will have
to create its own mapping anyway.
Signed-off-by: Thierry Reding <treding@nvidia.com>

All the devices that make up the DRM device are now part of the same
IOMMU group. This simplifies the handling of the IOMMU attachment and
also avoids exhausting the number of IOMMUs available on early Tegra
SoC generations.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The ->load() and ->unload() drivers are midlayers and should be avoided
in modern drivers. Fix this by moving the code into the driver ->probe()
and ->remove() implementations, respectively.

v2: kick out conflicting framebuffers before initializing fbdev
v3: rebase onto drm/tegra/for-next
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

In order to support different modes (DP in addition to HDMI), split out
the audio setup/teardown into callbacks.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The code to enable audio support is split into two parts, one being
generic for the SOR and another part that is specific whether the SOR is
in HDMI mode or in DP mode. Split out the common part in preparation for
reusing the code in DP mode.
Signed-off-by: Thierry Reding <treding@nvidia.com>

When the SOR is disabled in DP mode as part of an unplug event, do not
attempt to power the DP link down. Powering down the link requires the
DPAUX to transmit AUX messages which only works if there's a connected
sink.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The SOR0 on Tegra210 does, contrary to what was previously assumed, in
fact support DisplayPort. The difference between SOR0 and SOR1 is that
the latter supports audio and HDCP over DP, whereas the former doesn't.

The code for eDP and DP is now almost identical and the differences can
easily be parameterized based on the presence of a panel. There is no
need any longer to duplicate the code.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The correct I/O pad needs to be powered up before DP can be used. Make
sure the correct default is set for Tegra generations where the I/O pad
cannot be derived from the SOR instance.
Signed-off-by: Thierry Reding <treding@nvidia.com>

With the clocks modelled consistently across SoC generations, the clock
setup for eDP, HDMI and DP can now be unified.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Reuse parameters from earlier generations to support DisplayPort on
Tegra194.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The connector type detection code is duplicated in two places. Keeping
both places in sync is an extra maintenance burden that can be avoided
by comparing the connector type operations that are set upon the first
detection.
Signed-off-by: Thierry Reding <treding@nvidia.com>

So far the pad clock was only needed on the second SOR instance. The
clock does exist for all SOR instances, though, so make sure it is
always implemented. This prepares for further unification of the code
in subsequent patches.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The device tree bindings for the Tegra210 SOR don't require the
controller instance to be defined, since the instance can be derived
from the compatible string. The index is never used on Tegra210, so we
got away with it not getting set. However, subsequent patches will
change that, so make sure the proper index is used.
Signed-off-by: Thierry Reding <treding@nvidia.com>

It turns out that SOR1 is just another instance of the same block as the
SOR0, so there is no need to distinguish them.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Add support for regular DisplayPort on Tegra210 and Tegra186.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The SOR found on Tegra SoCs does not support all the rates potentially
advertised by eDP 1.4. Make sure that the rates that are not supported
are filtered out.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Rework eDP code to correspond more closely to what's documented. This
also improves the reliability of modesets.
Signed-off-by: Thierry Reding <treding@nvidia.com>

This is necessary for the output abstraction to retrieve a list of valid
modes from the EDID of a connected panel/monitor. This will be useful in
conjunction with DisplayPort support that will be added in a subsequent
patch, so that the driver can read EDID via the AUX channel.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Make use of the DP link training helpers to implement full and fast link
training. While at it, refactor some of the code and remove various code
sequences that are not necessary.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Add a helper that will perform link training as described in the
DisplayPort specification.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Parses additional link rates from DPCD if the sink supports eDP 1.4.
Signed-off-by: Thierry Reding <treding@nvidia.com>

This helper chooses an appropriate configuration, according to the
bitrate requirements of the video mode and the capabilities of the
DisplayPort sink.
Signed-off-by: Thierry Reding <treding@nvidia.com>

If the sink is eDP and supports the alternate scrambler reset, enable
it.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Make use of ANSI 8B/10B channel coding if the DisplayPort sink supports
it.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Store the AUX read interval from DPCD, so that it can be used to wait
for the durations given in the specification during link training.
Signed-off-by: Thierry Reding <treding@nvidia.com>

If the sink supports eDP, read the eDP revision from it's DPCD.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Parse from the sink capabilities whether or not the eDP alternate
scrambler reset value of 0xfffe is supported.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Parse from the sink capabilities whether or not it supports ANSI 8B/10B
channel coding as specified in ANSI X3.230-1994, clause 11.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The TPS3 capability can be exposed by DP 1.2 and later sinks if they
support the alternative training pattern for channel equalization.
Signed-off-by: Thierry Reding <treding@nvidia.com>

While probing the DisplayPort link, query the fast training capability.
If supported, drivers can use the fast link training sequence instead of
the more involved full link training sequence.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Use existing parsing helpers to probe a DisplayPort link.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Rather than storing capabilities as flags in an integer, use a separate
boolean per capability. This simplifies the code that checks for these
capabilities.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Store capabilities in max_* fields and add separate fields for the
currently selected settings.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Subsequent patches will add non-volatile fields to struct drm_dp_link,
so introduce a function to zero out only the volatile fields.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The drm_dp_link structure tracks capabilities on the DP link. Add some
kerneldoc to explain what each of its fields means.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The CMH, DRVZ and DRVI values vary depending on the SoC generation. Move
them into SoC specific structures so that DT compatible string matching
can be used to select the right parameters and write them to hardware at
the right time.
Signed-off-by: Thierry Reding <treding@nvidia.com>

In order to properly make the VDD supply optional, all accesses to the
regulator need to be ignored, because the regulator core doesn't treat
NULL special.
Signed-off-by: Thierry Reding <treding@nvidia.com>

When a transfer didn't complete transmission of the requested number of
bytes, signal that the transaction should be retried.
Signed-off-by: Thierry Reding <treding@nvidia.com>

The dpaux driver has a quirk built-in that will delay initialization of
the display driver for a short while, trying to detect an eDP panel. The
reason for this quirk is that the panel may not report as connected
until after the display driver has initialized, at which point the fbdev
emulation will have fallen back to 1024x768 as default resolution, which
will likely not be the eDP panel's native resolution.

With upcoming DisplayPort support, the code needs to be able to cope
with hotpluggable monitors as well. Waiting for a panel to show up is no
longer going to work because the monitor may not be attached on boot. If
the output runs in DisplayPort mode, skip waiting for the panel to show
up.
Signed-off-by: Thierry Reding <treding@nvidia.com>

Instead of manually creating the SG table for a discontiguous buffer,
use the existing sg_alloc_table_from_pages(). Note that this is not safe
to be used with the ARM DMA/IOMMU integration code because that will not
ensure that the whole buffer is mapped contiguously. Depending on the
size of the individual entries the mapping may end up containing holes
to ensure alignment.

However, we only ever use these buffers with explicit IOMMU API usage
and know how to avoid these holes.
Signed-off-by: Thierry Reding <treding@nvidia.com>