This partially reverts the DMA API support that was recently merged
because it was causing performance regressions on older Tegra devices.
Unfortunately, the cache maintenance performed by dma_map_sg() and
dma_unmap_sg() causes performance to drop by a factor of 10.

The right solution for this would be to cache mappings for buffers per
consumer device, but that's a bit involved. Instead, we simply revert to
the old behaviour of sharing IOVA mappings when we know that devices can
do so (i.e. they share the same IOMMU domain).

Cc: <stable@vger.kernel.org> # v5.5
Reported-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Reviewed-by: Dmitry Osipenko <digetx@gmail.com>

All the display related blocks on Tegra require contiguous memory. Using
the DMA API, there is no knowing at import time which device will end up
using the buffer, so it's not known whether or not an IOMMU will be used
to map the buffer.

Move the check for non-contiguous buffers/mappings to the tegra_dc_pin()
function which is now the earliest point where it is known if a DMA BUF
can be used by the given device or not.

v2: add check for contiguous buffer/mapping in tegra_dc_pin()

Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Thierry Reding <treding@nvidia.com>

If a display controller is not attached to an explicit IOMMU domain,
which usually means that it's connected to an IOMMU domain controlled by
the DMA API, make sure to map the framebuffer to the display controller
address space. This allows us to transparently handle setups where the
display controller is attached to an IOMMU or setups where it isn't. It
also allows the driver to work with a DMA API that is backed by an
IOMMU.

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

Drop use of the deprecated drmP.h header file.

For all touched files divide include files into blocks,
and sort them within the blocks.
Fix fallout.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Thierry Reding <treding@nvidia.com>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: linux-tegra@vger.kernel.org
Link: https://patchwork.freedesktop.org/patch/msgid/20190804094132.29463-3-sam@ravnborg.org

Based on 2 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Currently only the DRM_MODE_REFLECT_Y rotation is supported. The driver
already supports reflection on the Y axis via a custom flag which is not
very useful because it requires custom userspace. Add the standard
rotation property that supports 0 degree rotation and Y axis reflection
for primary and overlay planes to provide a better interface than the
custom flag.

v2: keep custom flag for ABI compatibility (Dmitry)

Reviewed-by: Dmitry Osipenko <digetx@gmail.com>
Tested-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Older Tegra's do not support plane's Z position handling in hardware,
but the hardware provides knobs to implement it in software.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
Signed-off-by: Thierry Reding <treding@nvidia.com>

Linux 4.16-rc7

This was requested by Daniel, and things were getting
a bit hard to reconcile, most of the conflicts were
trivial though.

drm/tegra: Changes for v4.17-rc1

This fixes mmap() for fbdev devices by providing a custom implementation
based on the KMS variant. This is a fairly exotic case these days, hence
why it is not flagged for stable.

There is also support for dedicating one of the overlay planes to serve
as a hardware cursor on older Tegra that did support hardware cursors
but not RGBA formats for it.

Planes will now also export the IN_FORMATS property by supporting the
various block-linear tiling modifiers for RGBA pixel formats.

Other than that, there's a bit of cleanup of DMA API abuse, use of the
private object infrastructure for global state (rather than subclassing
atomic state objects) and an implementation of ->{begin,end}_cpu_access
callbacks for PRIME exported buffers, which allow users to perform cache
maintenance on these buffers.

* tag 'drm/tegra/for-4.17-rc1' of git://anongit.freedesktop.org/tegra/linux:
  drm/tegra: prime: Implement ->{begin,end}_cpu_access()
  drm/tegra: gem: Map pages via the DMA API
  drm/tegra: hub: Use private object for global state
  drm/tegra: fb: Properly support linear modifier
  drm/tegra: plane: Support format modifiers
  drm/tegra: dc: Dedicate overlay plane to cursor on older Tegra's
  drm/tegra: plane: Make tegra_plane_get_overlap_index() static
  drm/tegra: fb: Implement ->fb_mmap() callback
  drm/tegra: gem: Make __tegra_gem_mmap() available more widely
  drm/tegra: gem: Reshuffle declarations

Pass the list of valid format modifiers to planes upon initialization
and implement the ->format_mod_supported() callback so that userspace
can query for the valid combinations of formats and modifiers.

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