8f7525a8b9
commit 468c49f44759720a312e52d44a71c3949ed63d7c upstream.
When interrupt auto clear is programmed, any read to the interrupt
status register will clear all interrupts. If two interrupts have
come in before one can be serviced then this will cause lost interrupts.
On AMD USB4 routers this has manifested in odd problems particularly
with long strings of control tranfers such as reading the DROM via bit
banging.
Instead of clearing interrupts automatically, clear the bit corresponding
to the given ring's interrupt in the ISR.
Fixes: 7a1808f82a37 ("thunderbolt: Handle ring interrupt by reading interrupt status register")
Cc: Sanju Mehta <Sanju.Mehta@amd.com>
Cc: stable@vger.kernel.org
Tested-by: Anson Tsao <anson.tsao@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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.