drm/tegra: Changes for v4.2-rc1

This contains a couple of mostly fixes for issues that have crept up in
recent versions of linux-next. One issue is that DP AUX transactions of
more than 4 bytes will access the wrong FIFO registers and hence become
corrupt. Another fix is required to restore functionality of Tegra20 if
using the GART. The current code expects the IOMMU aperture to be the
complete 4 GiB address space, whereas the GART on Tegra20 only provides
a 128 MiB aperture. One more issue with IOMMU support is that on 64-bit
ARM, swiotlb is the default IOMMU implementation backing the DMA API. A
side-effect of that is that when dma_map_sg() is called to flush caches
(yes, this is a bit of a hack, but ARM does not provide a better API),
swiotlb will immediately run out of memory because its bounce buffer is
too small to make a framebuffer.

Finally I've included a mostly cosmetic fix that stores register values
in u32 rather than unsigned long to avoid sign-extension issues on 64-
bit ARM. This is only a precaution since it hasn't caused any issues
(yet).

* tag 'drm/tegra/for-4.2-rc1' of git://anongit.freedesktop.org/tegra/linux:
  drm/tegra: dpaux: Registers are 32-bit
  drm/tegra: gem: Flush pages after allocation
  drm/tegra: gem: Take into account IOMMU aperture
  drm/tegra: dpaux: Fix transfers larger than 4 bytes

The IOMMU may not always be able to address 2 GiB of memory. On Tegra20,
the GART supports 32 MiB starting at 0x58000000. Also the aperture on
Tegra30 and later is in fact the full 4 GiB, rather than just 2 GiB as
currently assumed.

Signed-off-by: Thierry Reding <treding@nvidia.com>

Tegra would not only need a hardware vblank counter that
increments at leading edge of vblank, but also support
for instantaneous high precision vblank timestamp queries, ie.
a proper implementation of dev->driver->get_vblank_timestamp().

Without these, there can be off-by-one errors during vblank
disable/enable if the scanout is inside vblank at en/disable
time, and additionally clients will never see any useable
vblank timestamps when querying via drmWaitVblank ioctl. This
would negatively affect swap scheduling under X11 and Wayland.

Signed-off-by: Mario Kleiner <mario.kleiner.de@gmail.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drm/tegra: Changes for v4.1-rc1

Perhaps the most noteworthy change in this set is the implementation of
a hardware VBLANK counter using host1x syncpoints. The SOR registers can
now be dumped via debugfs, which can be useful while debugging. The IOVA
address space maintained by the driver can also be dumped via debugfs.

Other than than, these changes are mostly cleanup work, such as making
register names more consistent or removing unused code (that was left
over after the atomic mode-setting conversion). There's also a fix for
eDP that makes the driver cope with firmware that already initialized
the display (such as the firmware on the Tegra-based Chromebooks).

* tag 'drm/tegra/for-4.1-rc1' of git://anongit.freedesktop.org/tegra/linux:
  drm/tegra: sor: Reset during initialization
  drm/tegra: gem: Return 64-bit offset for mmap(2)
  drm/tegra: hdmi: Name register fields consistently
  drm/tegra: hdmi: Resets are synchronous
  drm/tegra: dc: Document tegra_dc_state_setup_clock()
  drm/tegra: dc: Remove unused callbacks
  drm/tegra: dc: Remove unused function
  drm/tegra: dc: Use base atomic state helpers
  drm/atomic: Add helpers for state-subclassing drivers
  drm/tegra: dc: Implement hardware VBLANK counter
  gpu: host1x: Export host1x_syncpt_read()
  drm/tegra: sor: Dump registers via debugfs
  drm/tegra: sor: Registers are 32-bit
  drm/tegra: Provide debugfs file for the IOVA space
  drm/tegra: dc: Check for valid parent clock

The display controller on Tegra can use syncpoints to count VBLANK
events. syncpoints are 32-bit unsigned integers, so well suited as
VBLANK counters.

Signed-off-by: Thierry Reding <treding@nvidia.com>

The Tegra DRM driver uses a single IO virtual address space for buffer
mappings. Provide a table of the address space usage in debugfs.

Signed-off-by: Thierry Reding <treding@nvidia.com>

These names only make sense because of backwards compatability with
the order used by the crtc helper library. There's not really any real
requirement in the ordering here.

So rename them to something more descriptive and update the kerneldoc
a bit. Motivated in a discussion with Laurent about how to restore
plane state for dpms for drivers with runtime pm.

v2: Squash in fixup from Stephen Rothwell to fix a conflict with
tegra.

Cc: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Reviewed-by: Rob Clark <robdclark@gmail.com>
Acked-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>

When copying a relocation from userspace, copy the correct target
offset.

Signed-off-by: David Ung <davidu@nvidia.com>
Fixes: 961e3beae3b2 ("drm/tegra: Make job submission 64-bit safe")
Cc: stable@vger.kernel.org
[treding@nvidia.com: provide a better commit message]
Signed-off-by: Thierry Reding <treding@nvidia.com>

For now only disable the KMS hotplug polling helper logic upon suspend
and re-enable it on resume.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Reviewed-by: Mark Zhang <markz@nvidia.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Provide a custom ->atomic_commit() implementation which supports async
commits. The generic atomic page-flip helper can use this to implement
page-flipping.

Signed-off-by: Thierry Reding <treding@nvidia.com>