Kernel Source and devicetree for NOTHING Phone(3a) and Phone(3a)Pro
Find a file
Brian Norris db0a9a2991 drm/atomic: Allow vblank-enabled + self-refresh "disable"
commit 9d0e3cac3517942a6e00eeecfe583a98715edb16 upstream.

The self-refresh helper framework overloads "disable" to sometimes mean
"go into self-refresh mode," and this mode activates automatically
(e.g., after some period of unchanging display output). In such cases,
the display pipe is still considered "on", and user-space is not aware
that we went into self-refresh mode. Thus, users may expect that
vblank-related features (such as DRM_IOCTL_WAIT_VBLANK) still work
properly.

However, we trigger the WARN_ONCE() here if a CRTC driver tries to leave
vblank enabled.

Add a different expectation: that CRTCs *should* leave vblank enabled
when going into self-refresh.

This patch is preparation for another patch -- "drm/rockchip: vop: Leave
vblank enabled in self-refresh" -- which resolves conflicts between the
above self-refresh behavior and the API tests in IGT's kms_vblank test
module.

== Some alternatives discussed: ==

It's likely that on many display controllers, vblank interrupts will
turn off when the CRTC is disabled, and so in some cases, self-refresh
may not support vblank. To support such cases, we might consider
additions to the generic helpers such that we fire vblank events based
on a timer.

However, there is currently only one driver using the common
self-refresh helpers (i.e., rockchip), and at least as of commit
bed030a49f ("drm/rockchip: Don't fully disable vop on self refresh"),
the CRTC hardware is powered enough to continue to generate vblank
interrupts.

So we chose the simpler option of leaving vblank interrupts enabled. We
can reevaluate this decision and perhaps augment the helpers if/when we
gain a second driver that has different requirements.

v3:
 * include discussion summary

v2:
 * add 'ret != 0' warning case for self-refresh
 * describe failing test case and relation to drm/rockchip patch better

Cc: <stable@vger.kernel.org> # dependency for "drm/rockchip: vop: Leave
                             # vblank enabled in self-refresh"
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Sean Paul <seanpaul@chromium.org>
Link: https://patchwork.freedesktop.org/patch/msgid/20230109171809.v3.1.I3904f697863649eb1be540ecca147a66e42bfad7@changeid
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-07-23 13:49:39 +02:00
arch MIPS: KVM: Fix NULL pointer dereference 2023-07-23 13:49:33 +02:00
block blk-crypto: use dynamic lock class for blk_crypto_profile::lock 2023-07-23 13:49:21 +02:00
certs certs: Fix build error when PKCS#11 URI contains semicolon 2023-02-09 11:28:11 +01:00
crypto crypto: jitter - correct health test during initialization 2023-07-19 16:21:42 +02:00
Documentation dm init: add dm-mod.waitfor to wait for asynchronously probed block devices 2023-07-23 13:49:38 +02:00
drivers drm/atomic: Allow vblank-enabled + self-refresh "disable" 2023-07-23 13:49:39 +02:00
fs fs: dlm: fix mismatch of plock results from userspace 2023-07-23 13:49:38 +02:00
include net/sched: make psched_mtu() RTNL-less safe 2023-07-23 13:49:27 +02:00
init gcc: disable '-Warray-bounds' for gcc-13 too 2023-04-26 14:28:43 +02:00
io_uring io_uring: Use io_schedule* in cqring wait 2023-07-19 16:22:18 +02:00
ipc ipc: fix memory leak in init_mqueue_fs() 2022-12-31 13:32:01 +01:00
kernel tracing/user_events: Fix incorrect return value for writing operation when events are disabled 2023-07-23 13:49:32 +02:00
lib lib/bitmap: drop optimization of bitmap_{from,to}_arr64 2023-07-19 16:21:58 +02:00
LICENSES LICENSES/LGPL-2.1: Add LGPL-2.1-or-later as valid identifiers 2021-12-16 14:33:10 +01:00
mm kasan: add kasan_tag_mismatch prototype 2023-07-23 13:49:32 +02:00
net net/sched: sch_qfq: account for stab overhead in qfq_enqueue 2023-07-23 13:49:27 +02:00
rust rust: kernel: Mark rust_fmt_argument as extern "C" 2023-04-26 14:28:38 +02:00
samples samples/bpf: xdp1 and xdp2 reduce XDPBUFSIZE to 60 2023-07-19 16:21:07 +02:00
scripts kbuild: Disable GCOV for *.mod.o 2023-07-19 16:21:44 +02:00
security integrity: Fix possible multiple allocation in integrity_inode_get() 2023-07-19 16:22:11 +02:00
sound ASoC: mediatek: mt8173: Fix snd_soc_component_initialize error path 2023-07-19 16:22:14 +02:00
tools wireguard: netlink: send staged packets when setting initial private key 2023-07-19 16:22:17 +02:00
usr usr/gen_init_cpio.c: remove unnecessary -1 values from int file 2022-10-03 14:21:44 -07:00
virt KVM: Avoid illegal stage2 mapping on invalid memory slot 2023-06-28 11:12:23 +02:00
.clang-format inet: ping: use hlist_nulls rcu iterator during lookup 2022-12-01 12:42:46 +01:00
.cocciconfig
.get_maintainer.ignore get_maintainer: add Alan to .get_maintainer.ignore 2022-08-20 15:17:44 -07:00
.gitattributes
.gitignore Kbuild: add Rust support 2022-09-28 09:02:20 +02:00
.mailmap 9 hotfixes. 6 for MM, 3 for other areas. Four of these patches address 2022-12-10 17:10:52 -08:00
.rustfmt.toml rust: add .rustfmt.toml 2022-09-28 09:02:20 +02:00
COPYING COPYING: state that all contributions really are covered by this file 2020-02-10 13:32:20 -08:00
CREDITS MAINTAINERS: Remove Michal Marek from Kbuild maintainers 2022-11-16 14:53:00 +09:00
Kbuild Kbuild updates for v6.1 2022-10-10 12:00:45 -07:00
Kconfig kbuild: ensure full rebuild when the compiler is updated 2020-05-12 13:28:33 +09:00
MAINTAINERS smb: move client and server files to common directory fs/smb 2023-06-28 11:12:40 +02:00
Makefile Linux 6.1.39 2023-07-19 16:22:18 +02:00
README

Linux kernel
============

There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.

In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``.  The formatted documentation can also be read online at:

    https://www.kernel.org/doc/html/latest/

There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.

Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.