Accessing the crtc->state pointer from outside the modesetting context
is not allowed. We thus need to copy whatever we need from the KMS state
to our structure in order to access it.
In VC4, a number of users of that pointers have crept in over the years,
and the previous commits removed them all but the HVS channel a CRTC has
been assigned.
Let's move this channel in struct vc4_crtc at atomic_begin() time, drop
it from our private state structure, and remove our use of crtc->state
from our vblank handler entirely.
Link: https://lore.kernel.org/all/YWgteNaNeaS9uWDe@phenom.ffwll.local/
Link: https://lore.kernel.org/r/20211025141113.702757-4-maxime@cerno.tech
Fixes: 87ebcd42fb ("drm/vc4: crtc: Assign output to channel automatically")
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
In some situation, we can end up being stuck on a non-blocking that went
through properly.
The situation that seems to trigger it reliably is to first start a
non-blocking commit, and then right after, and before we had any vblank
interrupt), start a blocking commit.
This will lead to the first commit workqueue to be scheduled, setup the
display, while the second commit is waiting for the first one to be
completed.
The vblank interrupt will then be raised, vc4_crtc_handle_vblank() will
run and will compare the active dlist in the HVS channel to the one
associated with the crtc->state.
However, at that point, the second commit is waiting using
drm_atomic_helper_wait_for_dependencies that occurs after
drm_atomic_helper_swap_state has been called, so crtc->state points to
the second commit state. vc4_crtc_handle_vblank() will compare the two
dlist addresses and since they don't match will ignore the interrupt.
The vblank event will never be reported, and the first and second commit
will wait for the first commit completion until they timeout.
The underlying reason is that it was never safe to do so. Indeed,
accessing the ->state pointer access synchronization is based on
ownership guarantees that can only occur within the functions and hooks
defined as part of the KMS framework, and obviously the irq handler
isn't one of them. The rework to move to generic helpers only uncovered
the underlying issue.
However, since the code path between
drm_atomic_helper_wait_for_dependencies() and
drm_atomic_helper_wait_for_vblanks() is serialised and we can't get two
commits in that path at the same time, we can work around this issue by
setting a variable associated to struct drm_crtc to the dlist we expect,
and then using it from the vc4_crtc_handle_vblank() function.
Since that state is shared with the modesetting path, we also need to
introduce a spinlock to protect the code shared between the interrupt
handler and the modesetting path, protecting only our new variable for
now.
Link: https://lore.kernel.org/all/YWgteNaNeaS9uWDe@phenom.ffwll.local/
Link: https://lore.kernel.org/r/20211025141113.702757-3-maxime@cerno.tech
Fixes: 56d1fe0979 ("drm/vc4: Make pageflip completion handling more robust.")
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Accessing the crtc->state pointer from outside the modesetting context
is not allowed. We thus need to copy whatever we need from the KMS state
to our structure in order to access it.
In VC4, a number of users of that pointers have crept in over the years,
the first one being whether or not the downstream controller of the
pixelvalve is our writeback controller.
Fortunately for us, Since commit 39fcb28083 ("drm/vc4: txp: Turn the
TXP into a CRTC of its own") this is no longer something that can change
from one commit to the other and is hardcoded.
Let's set this flag in struct vc4_crtc if we happen to be the TXP, and
drop the flag from our private state structure.
Link: https://lore.kernel.org/all/YWgteNaNeaS9uWDe@phenom.ffwll.local/
Link: https://lore.kernel.org/r/20211025141113.702757-2-maxime@cerno.tech
Fixes: 008095e065 ("drm/vc4: Add support for the transposer block")
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
LBM base address is measured in units of pixels per cycle.
That is 4 for 2711 (hvs5) and 2 for 2708.
We are wasting 75% of lbm by indexing without the scaling.
But we were also using too high a size for the lbm resulting
in partial corruption (right hand side) of vertically
scaled images, usually at 4K or lower resolutions with more layers.
The physical RAM of LBM on 2711 is 8 * 1920 * 16 * 12-bit
(pixels are stored 12-bits per component regardless of format).
The LBM address indexes work in units of pixels per clock,
so for 4 pixels per clock that means we have 32 * 1920 = 60K
Fixes: c54619b0bf ("drm/vc4: Add support for the BCM2711 HVS5")
Signed-off-by: Dom Cobley <popcornmix@gmail.com>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Reviewed-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
Tested-By: Lucas Nussbaum <lucas@debian.org>
Tested-By: Ryutaroh Matsumoto <ryutaroh@ict.e.titech.ac.jp>
Link: https://patchwork.freedesktop.org/patch/msgid/20210121105759.1262699-1-maxime@cerno.tech
We need commit f8f6ae5d07 ("mm: always have io_remap_pfn_range() set
pgprot_decrypted()") to be able to merge Jason's cleanup patch.
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>
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>
The global list of all debugfs entries for the driver was painful: the
list couldn't see into the components' structs, so each component had
its own debugs show function to find the component, then find the
regset and dump it. The components also had to be careful to check
that they were actually registered in vc4 before dereferencing
themselves, in case they weren't probed on a particular platform.
They routinely failed at that.
Instead, we can have the components add their debugfs callbacks to a
little list in vc4 to be registered at drm_dev_register() time, which
gets vc4_debugfs.c out of the business of knowing the whole list of
components.
Thanks to this change, dsi0 (if it existed) would register its node.
v2: Rebase on hvs_underrun addition.
v3: whitespace fixup
Signed-off-by: Eric Anholt <eric@anholt.net>
Link: https://patchwork.freedesktop.org/patch/msgid/20190401183559.3823-1-eric@anholt.net
Reviewed-by: Paul Kocialkowski <paul.kocialkowski@bootlin.com>
I had written most of my comments as if I was describing the
individual code files the way I used to for doxygen, while for RST we
want to describe things in a more chapter/section way where there's no
obvious relation to .c files.
Additionally, several of the files had stub descriptions that I've
taken this opportunity to extend.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Link: http://patchwork.freedesktop.org/patch/msgid/20170227201144.10970-4-eric@anholt.net
This implements a simple policy for choosing scaling modes
(trapezoidal for decimation, PPF for magnification), and a single PPF
filter (Mitchell/Netravali's recommendation).
Signed-off-by: Eric Anholt <eric@anholt.net>
So far, we've only ever lit up one CRTC, so this has been fine. To
extend to more displays or more planes, we need to make sure we don't
run our display lists into each other.
Signed-off-by: Eric Anholt <eric@anholt.net>
This is enough for fbcon and bringing up X using
xf86-video-modesetting. It doesn't support the 3D accelerator or
power management yet.
v2: Drop FB_HELPER select thanks to Archit's patches. Do manual init
ordering instead of using the .load hook. Structure registration
more like tegra's, but still using the typical "component" code.
Drop no-op hooks for atomic_begin and mode_fixup() now that
they're optional. Drop sentinel in Makefile. Fix minor style
nits I noticed on another reread.
v3: Use the new bcm2835 clk driver to manage pixel/HSM clocks instead
of having a fixed video mode. Use exynos-style component driver
matching instead of devicetree nodes to list the component driver
instances. Rename compatibility strings to say bcm2835, and
distinguish pv0/1/2. Clean up some h/vsync code, and add in
interlaced mode setup. Fix up probe/bind error paths. Use
bitops.h macros for vc4_regs.h
v4: Include i2c.h, allow building under COMPILE_TEST, drop msleep now
that other bugs have been fixed, add timeouts to cpu_relax()
loops, rename hpd-gpio to hpd-gpios.
Signed-off-by: Eric Anholt <eric@anholt.net>
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
