From: Ben Hutchings Date: Thu, 17 Jun 2010 19:16:36 +0000 (+0100) Subject: PCI: MSI: Remove unsafe and unnecessary hardware access X-Git-Tag: v2.6.36-rc1~518^2~11 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fcd097f31a6ee207cc0c3da9cccd2a86d4334785;p=pandora-kernel.git PCI: MSI: Remove unsafe and unnecessary hardware access During suspend on an SMP system, {read,write}_msi_msg_desc() may be called to mask and unmask interrupts on a device that is already in a reduced power state. At this point memory-mapped registers including MSI-X tables are not accessible, and config space may not be fully functional either. While a device is in a reduced power state its interrupts are effectively masked and its MSI(-X) state will be restored when it is brought back to D0. Therefore these functions can simply read and write msi_desc::msg for devices not in D0. Further, read_msi_msg_desc() should only ever be used to update a previously written message, so it can always read msi_desc::msg and never needs to touch the hardware. Tested-by: "Michael Chan" Signed-off-by: Ben Hutchings Signed-off-by: Jesse Barnes --- Reading git-diff-tree failed