9913a07850
[ Upstream commit 9eec61df55c51415409c7cc47e9a1c8de94a0522 ]
The irq_eoi() callback of the RZ/G2L interrupt chip clears the relevant
interrupt cause bit in the TSCR register by writing to it.
This write is not sufficient because the write is posted and therefore not
guaranteed to immediately clear the bit. Due to that delay the CPU can
raise the just handled interrupt again.
Prevent this by reading the register back which causes the posted write to
be flushed to the hardware before the read completes.
Fixes: 3fed09559cd8 ("irqchip: Add RZ/G2L IA55 Interrupt Controller driver")
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.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.