drm/msm: Allow a5xx to mark the RPTR shadow as privileged

Newer microcode versions have support for the CP_WHERE_AM_I opcode which
allows the RPTR shadow memory to be marked as privileged to protect it
from corruption. Move the RPTR shadow into its own buffer and protect it
it if the current microcode version supports the new feature.

We can also re-enable preemption for those targets that support
CP_WHERE_AM_I. Start out by preemptively assuming that we can enable
preemption and disable it in a5xx_hw_init if the microcode version comes
back as too old.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drm/msm: Split the a5xx preemption record

The main a5xx preemption record can be marked as privileged to
protect it from user access but the counters storage needs to be
remain unprivileged. Split the buffers and mark the critical memory
as privileged.

Cc: stable@vger.kernel.org
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@chromium.org>

drm: convert .debugfs_init() hook to return void.

As a result of commit 987d65d01356 (drm: debugfs: make
drm_debugfs_create_files() never fail) and changes to various debugfs
functions in drm/core and across various drivers, there is no need for
the drm_driver.debugfs_init() hook to have a return value. Therefore,
declare it as void.

This also includes refactoring all users of the .debugfs_init() hook to
return void across the subsystem.

v2: include changes to the hook and drivers that use it in one patch to
prevent driver breakage and enable individual successful compilation of
this change.

References: https://lists.freedesktop.org/archives/dri-devel/2020-February/257183.html
Signed-off-by: Wambui Karuga <wambui.karugax@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20200310133121.27913-18-wambui.karugax@gmail.com

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 284

Based on 1 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 and
only version 2 as published by the free software foundation this
program is distributed in the hope that it will be useful but
without any warranty without even the implied warranty of
merchantability or fitness for a particular purpose see the gnu
general public license for more details

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 294 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190529141900.825281744@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drm/msm: add a5xx specific debugfs

Add some debugfs to dump out PFP and ME microcontroller state, as well
as some of the queues (MEQ and ROQ). Also add a debugfs file to trigger
a GPU reset (and reloading the firmware on next submit).

Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: Implement preemption for A5XX targets

Implement preemption for A5XX targets - this allows multiple
ringbuffers for different priorities with automatic preemption
of a lower priority ringbuffer if a higher one is ready.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: Support multiple ringbuffers

Add the infrastructure to support the idea of multiple ringbuffers.
Assign each ringbuffer an id and use that as an index for the various
ring specific operations.

The biggest delta is to support legacy fences. Each fence gets its own
sequence number but the legacy functions expect to use a unique integer.
To handle this we return a unique identifier for each submission but
map it to a specific ring/sequence under the covers. Newer users use
a dma_fence pointer anyway so they don't care about the actual sequence
ID or ring.

The actual mechanics for multiple ringbuffers are very target specific
so this code just allows for the possibility but still only defines
one ringbuffer for each target family.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: Remove uneeded platform dev members

Commit eeb754746b14 ("drm/msm/gpu: use pm-runtime") adds a pointer
for the GPU platform device to the msm_gpu struct so we can
happily remove the same pointers from the individual GPU
structs.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: gpu: don't abuse dma_alloc for non-DMA allocations

In zap_shader_load_mdt(), we pass a pointer to a phys_addr_t
into dmam_alloc_coherent, which the compiler warns about:

drivers/gpu/drm/msm/adreno/a5xx_gpu.c: In function 'zap_shader_load_mdt':
drivers/gpu/drm/msm/adreno/a5xx_gpu.c:54:50: error: passing argument 3 of 'dmam_alloc_coherent' from incompatible pointer type [-Werror=incompatible-pointer-types]

The returned DMA address is later passed on to a function that
takes a phys_addr_t, so it's clearly wrong to use the DMA
mapping interface here: the memory may be uncached, or the
address may be completely wrong if there is an IOMMU connected
to the device. What the code actually wants to do is to get
the physical address from the reserved-mem node. It goes through
the dma-mapping interfaces for obscure reasons, and this
apparently only works by chance, relying on specific bugs
in the error handling of the arm64 dma-mapping implementation.

The same problem existed in the "venus" media driver, which was
now fixed by Stanimir Varbanov after long discussions.

In order to make some progress here, I have now ported his
approach over to the adreno driver. The patch is currently
untested, and should get a good review, but it is now much
simpler than the original, and it should be obvious what
goes wrong if I made a mistake in the port.

See also: a6e2d36bf6b7 ("media: venus: don't abuse dma_alloc for non-DMA allocations")
Cc: Stanimir Varbanov <stanimir.varbanov@linaro.org>
Fixes: 7c65817e6d38 ("drm/msm: gpu: Enable zap shader for A5XX")
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-and-Tested-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: Allow hardware clock gating to be toggled

There are some use cases wherein we need to turn off hardware clock
gating before reading certain registers. Modify the A5XX HWCG function
to allow user to enable or disable clock gating at will.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: Remove idle function hook

There isn't any generic code that uses ->idle so remove it.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: gpu: Enable zap shader for A5XX

The A5XX GPU powers on in "secure" mode. In secure mode the GPU can
only render to buffers that are marked as secure and inaccessible
to the kernel and user through a series of hardware protections. In
practice secure mode is used to draw things like a UI on a secure
video frame.

In order to switch out of secure mode the GPU executes a special
shader that clears out the GMEM and other sensitve registers and
then writes a register. Because the kernel can't be trusted the
shader binary is signed and verified and programmed by the
secure world. To do this we need to read the MDT header and the
segments from the firmware location and put them in memory and
present them for approval.

For targets without secure support there is an out: if the
secure world doesn't support secure then there are no hardware
protections and we can freely write the SECVID_TRUST register from
the CPU. We don't have 100% confidence that we can query the
secure capabilities at run time but we have enough calls that
need to go right to give us some confidence that we're at least doing
something useful.

Of course if we guess wrong you trigger a permissions violation
which usually ends up in a system crash but thats a problem
that shows up immediately.

[v2: use child device per Bjorn]
[v3: use generic MDT loader per Bjorn]
[v4: use managed dma functions and ifdefs for the MDT loader]
[v5: Add depends for QCOM_MDT_LOADER]

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Acked-by: Bjorn Andersson <bjorn.andersson@linaro.org>
[robclark: fix Kconfig to use select instead of depends + #if IS_ENABLED()]
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: gpu: Add support for the GPMU

Most 5XX targets have GPMU (Graphics Power Management Unit) that
handles a lot of the heavy lifting for power management including
thermal and limits management and dynamic power collapse. While
the GPMU itself is optional, it is usually nessesary to hit
aggressive power targets.

The GPMU firmware needs to be loaded into the GPMU at init time via a
shared hardware block of registers. Using the GPU to write the microcode
is more efficient than using the CPU so at first load create an indirect
buffer that can be executed during subsequent initalization sequences.

After loading the GPMU gets initalized through a shared register
interface and then we mostly get out of its way and let it do
its thing.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>

drm/msm: gpu: Add A5XX target support

Add support for the A5XX family of Adreno GPUs.

Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>