From: Ben Hutchings <bhutchings@solarflare.com>
Date: Fri, 23 Jul 2010 13:56:28 +0000 (+0100)
Subject: PCI: MSI: Restore read_msi_msg_desc(); add get_cached_msi_msg_desc()
X-Git-Tag: v2.6.36-rc1~518^2~5
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=30da55242818a8ca08583188ebcbaccd283ad4d9;p=pandora-kernel.git

PCI: MSI: Restore read_msi_msg_desc(); add get_cached_msi_msg_desc()

commit 2ca1af9aa3285c6a5f103ed31ad09f7399fc65d7 "PCI: MSI: Remove
unsafe and unnecessary hardware access" changed read_msi_msg_desc() to
return the last MSI message written instead of reading it from the
device, since it may be called while the device is in a reduced
power state.

However, the pSeries platform code really does need to read messages
from the device, since they are initially written by firmware.
Therefore:
- Restore the previous behaviour of read_msi_msg_desc()
- Add new functions get_cached_msi_msg{,_desc}() which return the
  last MSI message written
- Use the new functions where appropriate

Acked-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
---

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