forked from Minki/linux
mainlining shenanigans
c4680c9785
DPAA2 MAC supports 1588 one step timestamping. If this option is enabled then for each transmitted PTP event packet, the 1588 SINGLE_STEP register is accessed to modify the following fields: -offset of the correction field inside the PTP packet -UDP checksum update bit, in case the PTP event packet has UDP encapsulation These values can change any time, because there may be multiple PTP clients connected, that receive various 1588 frame types: - L2 only frame - UDP / Ipv4 - UDP / Ipv6 - other The current implementation uses dpni_set_single_step_cfg to update the SINLGE_STEP register. Using an MC command on the Tx datapath for each transmitted 1588 message introduces high delays, leading to low throughput and consequently to a small number of supported PTP clients. Besides these, the nanosecond correction field from the PTP packet will contain the high delay from the driver which together with the originTimestamp will render timestamp values that are unacceptable in a GM clock implementation. This patch updates the Tx datapath for 1588 messages when single step timestamp is enabled and provides direct access to SINGLE_STEP register, eliminating the overhead caused by the dpni_set_single_step_cfg MC command. MC version >= 10.32 implements this functionality. If the MC version does not have support for returning the single step register base address, the driver will use dpni_set_single_step_cfg command for updates operations. All the delay introduced by dpni_set_single_step_cfg function will be eliminated (if MC version has support for returning the base address of the single step register), improving the egress driver performance for PTP packets when single step timestamping is enabled. Before these changes the maximum throughput for 1588 messages with single step hardware timestamp enabled was around 2000pps. After the updates the throughput increased up to 32.82 Mbps / 46631.02 pps. Signed-off-by: Radu Bulie <radu-andrei.bulie@nxp.com> Signed-off-by: David S. Miller <davem@davemloft.net> |
||
|---|---|---|
| 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.