Don't call the IOMMU directly, but go through the new cmdbuf abstraction.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Reviewed-by: NChristian Gmeiner <christian.gmeiner@gmail.com>

This will get more complex with the following changes, so move it
into its own place.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Reviewed-by: NChristian Gmeiner <christian.gmeiner@gmail.com>

If the GPU is done with one user command stream the buffers referenced
by this command stream may go away and get unmapped from the MMU. If
the write caches are still dirty at this point later evictions will run
into MMU faults, killing the GPU.

Make sure the write caches are flushed before signaling completion
of the user command stream.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Flushing works differently on MMUv2, in that it's only necessary
to set a single bit in the control register to flush all translation
units. A semaphore stall then makes sure that the flush has propagated
properly.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Both the safe/scratch address and the master TLB address are per pipe
with the CPU mapped registers not properly propagating to the
different translation units.

The only way to correctly configure all translation units is to have
a command stream snipped executed by the FE, before any other execution
can start.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

The GPU virtual address for the command buffers differs depending on
the IOMMU version. Move the calculation of the iova into etnaviv
mmu, to enable proper dispatch.
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Improve the readibility of the function which inserts command buffers
and other maintanence commands into the GPUs ring buffer.  We do this
by splitting the ring buffer reservation in two: one chunk for any
commands that need to be issued prior to the command buffer, and a
separate chunk for commands issued after the buffer.

The result is a much more obvious code flow in this function, and
localisation of the conditional maintanence commands prior to the
command buffer.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Clean up the GPU command submission path to prepare for the next change.
This makes the next change easier to read and understand.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Use the previous GPU pipe state when deciding which GPU caches should
be flushed prior to switching the current pipe.  This avoids infering
what the previously selected pipe was, and potentially flushing the
wrong caches.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Flush the GPU caches to ensure that any dirty data is pushed out before
stopping the front end.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Add tracking of the current execution state (iow, active GPU pipe).
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Extract out the arming of a semaphore from the pipe select code.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Extract out the replacement of the WAIT command with some other command.
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

Provide a helper etnaviv_buffer_reserve() to ensure that we can fit a
set of commands into the ring buffer without wrapping by moving code
out of etnaviv_buffer_queue().
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>

This adds the etnaviv DRM driver and hooks it up in Makefiles
and Kconfig.
Signed-off-by: NChristian Gmeiner <christian.gmeiner@gmail.com>
Signed-off-by: NRussell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: NLucas Stach <l.stach@pengutronix.de>
Acked-by: NDaniel Vetter <daniel.vetter@ffwll.ch>