From: Robert Hancock Date: Sat, 20 Feb 2010 01:10:15 +0000 (-0800) Subject: r8169: enable 64-bit DMA by default for PCI Express devices (v2) X-Git-Tag: v2.6.34-rc1~233^2~119 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=353176888386d9025062a12dcec08d49af10cf2c;p=pandora-kernel.git r8169: enable 64-bit DMA by default for PCI Express devices (v2) Currently use of 64-bit DMA is disabled in r8169 unless the user passes the use_dac module option. This is reasonable for conventional PCI devices where broken chipsets may not handle dual-address-cycle transfers properly for 32-bit slots and so this may not be safe. However, PCI Express should not have this problem and not using 64-bit DMA results in DMA transfers needlessly using the IOMMU or SWIOTLB. Set the use_dac module parameter to a new default value of -1 which results in 64-bit DMA being enabled by default for PCI Express devices only. Signed-off-by: Robert Hancock Signed-off-by: David S. Miller --- Reading git-diff-tree failed