drm/vc4: perfmon: Add missing mutex_destroy

vc4_perfmon_open_file() will instantiate a mutex for that file instance,
but we never call mutex_destroy () in vc4_perfmon_close_file().

Let's add that missing call.

Acked-by: Thomas Zimmermann <tzimmermann@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220711173939.1132294-67-maxime@cerno.tech

drm/vc4: perfmon: Fix variable dereferenced before check

Commit 30f8c74ca9b7 ("drm/vc4: Warn if some v3d code is run on BCM2711")
introduced a check in vc4_perfmon_get() that dereferences a pointer before
we checked whether that pointer is valid or not.

Let's rework that function a bit to do things in the proper order.

Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: 30f8c74ca9b7 ("drm/vc4: Warn if some v3d code is run on BCM2711")
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: José Expósito <jose.exposito89@gmail.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20220622080243.22119-1-maxime@cerno.tech

drm/vc4: Warn if some v3d code is run on BCM2711

The BCM2711 has a separate driver for the v3d, and thus we can't call
into any of the driver entrypoints that rely on the v3d being there.

Let's add a bunch of checks and complain loudly if that ever happen.

Reviewed-by: Melissa Wen <mwen@igalia.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/20220610115149.964394-15-maxime@cerno.tech

drm/vc4: replace idr_init() by idr_init_base()

idr_init() uses base 0 which is an invalid identifier for this driver.
The idr_alloc for this driver uses VC4_PERFMONID_MIN as start value for
ID range and it is #defined to 1. The new function idr_init_base allows
IDR to set the ID lookup from base 1. This avoids all lookups that
otherwise starts from 0 since 0 is always unused / available.

References: commit 6ce711f27500 ("idr: Make 1-based IDRs more efficient")

Signed-off-by: Deepak R Varma <mh12gx2825@gmail.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://patchwork.freedesktop.org/patch/msgid/20201105202135.GA145111@localhost

drm/vc4: Disable V3D interactions if the v3d component didn't probe.

One might want to use the VC4 display stack without using Mesa.
Similar to the debugfs fixes for not having all of the possible
display bits enabled, make sure you can't oops in vc4 if v3d isn't
enabled.

v2: Fix matching against other v3d variants (review by Paul), don't
forget to set irq_enabled so that the vblank uapi works
v3: Use -ENODEV instead of -EINVAL on Paul's suggestion.

Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190401183559.3823-2-eric@anholt.net
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>

drm/vc4: Use struct_size() in kzalloc()

One of the more common cases of allocation size calculations is finding
the size of a structure that has a zero-sized array at the end, along
with memory for some number of elements for that array. For example:

struct foo {
int stuff;
void *entry[];
};

instance = kzalloc(sizeof(struct foo) + count * sizeof(struct boo), GFP_KERNEL);

Instead of leaving these open-coded and prone to type mistakes, we can
now use the new struct_size() helper:

instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);

This code was detected with the help of Coccinelle.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Eric Anholt <eric@anholt.net>
Reviewed-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190131010015.GA32272@embeddedor

drm/vc4: Expose performance counters to userspace

The V3D engine has various hardware counters which might be interesting
to userspace performance analysis tools.

Expose new ioctls to create/destroy a performance monitor object and
query the counter values of this perfmance monitor.

Note that a perfomance monitor is given an ID that is only valid on the
file descriptor it has been allocated from. A performance monitor can be
attached to a CL submission and the driver will enable HW counters for
this request and update the performance monitor values at the end of the
job.

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20180112090926.12538-1-boris.brezillon@free-electrons.com