svn commit: r227406 - projects/head_mfi/sys/dev/mfi

[Xin LI]

Author: delphij
Date: Wed Nov  9 20:12:59 2011
New Revision: 227406
URL: http://svn.freebsd.org/changeset/base/227406

Log:
  Incorporate Scott Long's patch for mfi(4) that fixes mfi(4) timeouts for
  our hardware:
  
  mfi0 at pci0:2:0:0:        class=0x010400 card=0x100a1000 chip=0x00601000 rev=0x04 hdr=0x00
      vendor     = 'LSI Logic / Symbios Logic'
      device     = 'MegaRAID SAS 1078'

Modified:
  projects/head_mfi/sys/dev/mfi/mfi.c

Modified: projects/head_mfi/sys/dev/mfi/mfi.c
==============================================================================
--- projects/head_mfi/sys/dev/mfi/mfi.c	Wed Nov  9 19:09:03 2011	(r227405)
+++ projects/head_mfi/sys/dev/mfi/mfi.c	Wed Nov  9 20:12:59 2011	(r227406)
@@ -1239,6 +1239,12 @@ 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);