svn commit: r227611 - in stable: 7/sys/dev/mfi 8/sys/dev/mfi

[Xin LI]

Author: delphij
Date: Thu Nov 17 11:16:56 2011
New Revision: 227611
URL: http://svn.freebsd.org/changeset/base/227611

Log:
  MFC r227409:
  
  Do a dummy read to flush the interrupt ACK that we just performed,
  ensuring that everything is really, truly consistent.
  
  This fixes certain cases where one will see various:
    mfi0: COMMAND 0xffffffXXXXXXXXXX TIMEOUT AFTER XX SECONDS
  
  Requested by:	Vincent Hoffman <vince unsane co uk>

Modified:
  stable/8/sys/dev/mfi/mfi.c
Directory Properties:
  stable/8/sys/   (props changed)

Changes in other areas also in this revision:
Modified:
  stable/7/sys/dev/mfi/mfi.c
Directory Properties:
  stable/7/sys/   (props changed)

Modified: stable/8/sys/dev/mfi/mfi.c
==============================================================================
--- stable/8/sys/dev/mfi/mfi.c	Thu Nov 17 10:46:51 2011	(r227610)
+++ stable/8/sys/dev/mfi/mfi.c	Thu Nov 17 11:16:56 2011	(r227611)
@@ -932,6 +932,12 @@ mfi_intr(void *arg)
 	if (sc->mfi_check_clear_intr(sc))
 		return;
 
+	/*
+	 * Do a dummy read to flush the interrupt ACK that we just performed,
+	 * ensuring that everything is really, truly consistent.
+	 */
+	(void)sc->mfi_read_fw_status(sc);
+
 	pi = sc->mfi_comms->hw_pi;
 	ci = sc->mfi_comms->hw_ci;
 	mtx_lock(&sc->mfi_io_lock);