drm/radeon: check PS, WS index

Theoretically, it would be possible for a buggy or malicious VBIOS to
overwrite past the bounds of the passed parameters (or its own
workspace); add bounds checking to prevent this from happening.

Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3093
Signed-off-by: Alexander Richards <electrodeyt@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

gpu: drm: dead code elimination

this set adds support for removal of gpu drm dead code.

patch3 is similar with patch 1:
`num` is a data of u8 type and ATOM_MAX_HW_I2C_READ == 255,

so there is a impossible condition '(num > 255) => (0-255 > 255)'.

Signed-off-by: Pan Zhang <zhangpan26@huawei.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/radeon: drop use of drmP.h (2/2)

Drop use of drmP.h in remaining .c files.
To ease review a little the drmP.h removal was divided in two commits.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Cc: "Christian König" <christian.koenig@amd.com>
Cc: "David (ChunMing) Zhou" <David1.Zhou@amd.com>
Cc: David Airlie <airlied@linux.ie>
Cc: Daniel Vetter <daniel@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/20190608080241.4958-8-sam@ravnborg.org

drm/radeon: change function signature to pass full range

In function ‘radeon_process_i2c_ch’ a comparison of a u8 value against
255 is done. Since it is always false, change the signature of this
function to use an `int` instead, which match the type used in caller:
`radeon_atom_hw_i2c_xfer`.

Fix the following warning triggered with W=1:

CC [M] drivers/gpu/drm/radeon/atombios_i2c.o
drivers/gpu/drm/radeon/atombios_i2c.c: In function ‘radeon_process_i2c_ch’:
drivers/gpu/drm/radeon/atombios_i2c.c:71:11: warning: comparison is always false due to limited range of data type [-Wtype-limits]
if (num > ATOM_MAX_HW_I2C_READ) {
^

Reviewed-by: Huang Rui <ray.huang@amd.com>
Signed-off-by: Mathieu Malaterre <malat@debian.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/radeon: add locking around atombios scratch space usage

While developing MST support I noticed I often got the wrong data
back from a transaction, in a racy fashion. I noticed the scratch
space wasn't locked against concurrent users.

Based on a patch by Alex, but I've made it a bit more obvious when
things are locked.

Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drm/radeon: add a i2c bus mutex

The i2c and aux buses use the same pads so add
a mutex to protect access to the pads.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>

drivers: gpu: Move prototype declaration to header file radeon_mode.h from atombios_i2c.c

Move prototype declaration of function radeon_atom_copy_swap() to header
file drm/radeon/radeon_mode.h because it is used by more than one file.

This eliminates the following warnings in drm/radeon/atombios_dp.c:
drivers/gpu/drm/radeon/atombios_dp.c:53:6: warning: no previous prototype for ‘radeon_atom_copy_swap’ [-Wmissing-prototypes]

Signed-off-by: Rashika Kheria <rashika.kheria@gmail.com>
Reviewed-by: Josh Triplett <josh@joshtriplett.org>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/radeon/atom: fix bus probes when hw_i2c is set (v2)

When probing the bus, we need to set the byte count
to 0 rather than 1.

v2: Don't count the first byte.

bug:
https://bugzilla.kernel.org/show_bug.cgi?id=66241

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

radeon/i2c: do not count reg index in number of i2c byte we are writing.

Useless to count the register index in number of bytes we are writing.

Fixes a regression with hw i2c enabled.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

drm/radeon: atombios hw i2c fixes

These fixes make writes work properly. Previously
only reads worked. Note that this feature is off
by default.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

drm/radeon: fix endian bugs in hw i2c atom routines

Need to swap the data fetched over i2c properly. This
is the same fix as the endian fix for aux channel
transactions.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org

UAPI: (Scripted) Convert #include "..." to #include <path/...> in drivers/gpu/

Convert #include "..." to #include <path/...> in drivers/gpu/.

Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Dave Airlie <airlied@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Acked-by: Dave Jones <davej@redhat.com>

drm/radeon/kms/dce3+: add support for hw i2c using atom

Starting with DCE3 hardware, atom contains a general purpose
ProcessI2cChannelTransaction similar to ProcessAuxChannelTransaction.

Add an implementation using the atom tables for DCE3+ hardware.

This should be a little less CPU intensive than bit banging and
may work better in certain cases.

Enable it by setting the radeon hw_i2c module parameter to 1. E.g.,
radeon.hw_i2c=1
on the kernel command line in grub.

Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>