60a848c50d
This patch adds RX IRQ coalescing support to the driver. The mcp251xfd chip doesn't support proper hardware based coalescing, so this patch tries to implemented it in software. The RX-FIFO offers a "FIFO not empty" interrupt, which is used if no coalescing is active. With activated RX IRQ coalescing the "FIFO not empty" interrupt is disabled in the RX IRQ handler and the "FIFO half full" or "FIFO full interrupt" (depending on RX max coalesced frames IRQ) is used instead. To avoid RX CAN frame starvation a hrtimer is setup with RX coalesce usecs IRQ,on timer expiration the "FIFO not empty" is enabled again. Support for ethtool configuration is added in the next patch. Link: https://lore.kernel.org/20220313083640.501791-9-mkl@pengutronix.de Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
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.