Kai-Heng Feng
24f5e38a13
rtw88: Disable PCIe ASPM while doing NAPI poll on 8821CE
Many Intel based platforms face system random freeze after commit 9e2fd29864c5 ("rtw88: add napi support"). The commit itself shouldn't be the culprit. My guess is that the 8821CE only leaves ASPM L1 for a short period when IRQ is raised. Since IRQ is masked during NAPI polling, the PCIe link stays at L1 and makes RX DMA extremely slow. Eventually the RX ring becomes messed up: [ 1133.194697] rtw_8821ce 0000:02:00.0: pci bus timeout, check dma status Since the 8821CE hardware may fail to leave ASPM L1, manually do it in the driver to resolve the issue. Fixes: 9e2fd29864c5 ("rtw88: add napi support") Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=215131 BugLink: https://bugs.launchpad.net/bugs/1927808 Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com> Acked-by: Jian-Hong Pan <jhp@endlessos.org> Signed-off-by: Kalle Valo <kvalo@kernel.org> Link: https://lore.kernel.org/r/20211215114635.333767-1-kai.heng.feng@canonical.com
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.
Description
Languages
C
97.6%
Assembly
1%
Shell
0.5%
Python
0.3%
Makefile
0.3%