⏱ Time to read: 1 min 3 secs

Raspberry PI: SPI Performance On Linux 5.4+

A new pull request has been made for Linux 5.4+ about the SPI performance (Serial Peripheral Interface).  A big performance enhancement for the bc2835 (Raspberry Pi) driver for unidirectional transfers from Lukas Wunner.

It’s about 30us reduction in ping time with the optimizations and a 2% reduction in CPU time. SPI displays and other devices connected via SPI should benefit as well with faster performance. The optimization principally comes down to clearing the RX FIFO and zero-filling the TX FIFO.

This Pull Request also includes:

  • A big overhaul of the spi-fsl-dspi driver improving the code quality,
    performance and stability from Vladimir Oltean.
  • A big performance enhancement for the bc2835 (Raspberry Pi) driver
    for unidirectional transfers from Lukas Wunner.
  • Improved performance on small transfers for the uniphier driver from
    Keiji Hayashibara.
  • Lots of coccinelle generated cleanups from Yue Haibing.
  • New device support for Freescale ls2080a and Nuvoton NPCM FIU.

Linux 5.4+ will bring more major high lights features like the “lockdown” patches for LSM (Linux Security Module) that locks down access to various kernel hardware.  Features for AMD Radeon GPU targets, initial support for Intel Tigerlake with Gen12/Xe Graphics and Google’s FS-VERITY File Authentication supported by Google.

Source: https://www.phoronix.com/scan.php?page=article&item=linux-54-features&num=1