mainlining shenanigans
b931e199f1
[Why] We're sending the drm vblank event a frame too early in the case where the pageflip happens close to VUPDATE and ends up blocking the signal. The implementation in DM was previously correct *before* we started sending vblank events from VSTARTUP unconditionally to handle cases where HUBP was off, OTG was ON and userspace was still requesting some DRM planes enabled. As part of that patch series we dropped VUPDATE since it was deemed close enough to VSTARTUP, but there's a key difference betweeen VSTARTUP and VUPDATE - the VUPDATE signal can be blocked if we're holding the pipe lock. There was a fix recently to revert the unconditional behavior for the DCN VSTARTUP vblank event since it was sending the pageflip event on the wrong frame - once again, due to blocking VUPDATE and having the address start scanning out two frames later. The problem with this fix is it didn't update the logic that calls drm_crtc_handle_vblank(), so the timestamps are totally bogus now. [How] Essentially reverts most of the original VSTARTUP series but retains the behavior to send back events when active planes == 0. Some refactoring/cleanup was done to not have duplicated code in both the handlers. Fixes: |
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| arch | ||
| block | ||
| certs | ||
| crypto | ||
| Documentation | ||
| drivers | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| LICENSES | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .clang-format | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| 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.