Adding Kumar to the CC: list, since he might pick up the patch. Ira Snyder wrote:
> From 73e42fa58c93de8d4d429ba8e069b60c42037b58 Mon Sep 17 00:00:00 2001 > From: Ira W. Snyder <i...@ovro.caltech.edu> > Date: Thu, 23 Apr 2009 16:17:54 -0700 > Subject: [PATCH] fsldma: use PCI Read Multiple command > > By default, the Freescale 83xx DMA controller uses the PCI Read Line > command when reading data over the PCI bus. Setting the controller to use > the PCI Read Multiple command instead allows the controller to read much > larger bursts of data, which provides a drastic speed increase. > > The slowdown due to using PCI Read Line was only observed when a PCI-to-PCI > bridge was between the devices trying to communicate. > > A simple test driver showed an increase from 4MB/sec to 116MB/sec when > performing DMA over the PCI bus. Using DMA to transfer between blocks of > local SDRAM showed no change in performance with this patch. The dmatest > driver was also used to verify the correctness of the transfers, and showed > no errors. > > Signed-off-by: Ira W. Snyder <i...@ovro.caltech.edu> Acked-by: Timur Tabi <ti...@freescale.com> -- Timur Tabi Linux kernel developer at Freescale _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev