Major update to the 'twe' driver.

 - Layout reorganisation to enhance portability.  The driver now has
   a relatively MI 'core' and a FreeBSD-specific layer over the top.
   Since the NetBSD people have already done their own port, this is
   largely just to help me with the BSD/OS port.

 - Request ID allocation changed to improve performance (I'd been
   considering switching to this approach after having failed to come
   up with a better way to dynamically allocate request IDs, and seeing
   Andy Doran use it in the NetBSD port of the driver convinced me
   that I was wasting my time doing it any other way).  Now we just
   allocate all the requests up front.

 - Maximum request count bumped back to 255 after characterisation
   of a firmware issue (off-by-one causing it to crash with 256
   outstanding commands).

 - Control interface implemented.  This allows 3ware's '3dm' utility to
   talk to the controller.  3dm will be available from 3ware shortly.

 - Controller soft-reset feature added; if the controller signals a
   firmware or protocol error, the controller will be reset and all
   outstanding commands will be retried.

1 files changed, 26 insertions, 1 deletions

diff --git a/sys/modules/twe/Makefile b/sys/modules/twe/Makefile
index f12f4e9..2d0639b 100644
--- a/sys/modules/twe/Makefile
+++ b/sys/modules/twe/Makefile
@@ -1,7 +1,32 @@
 # $FreeBSD$
 
+#
+# The 3ware controller offers a choice of options related to handling of
+# mirror consistency in shutdown situations.
+#
+# If TWE_SHUTDOWN_NOTIFICATION is defined, the driver will inform the 
+# controller on clean shutdown.  On reboot after an unclean shutdown, the 
+# controller will perform a complete mirror rebuild.  This is the most
+# "safe" configuration, but it imposes a severe performance penalty in the
+# event of an unexpected reboot.
+#
+# In the alternate configuration, the controller assumes that all writes to
+# a mirror complete successfully.  In the case of an unclean shutdown,
+# mirror corruption may occur if the controller is reset or power is lost
+# during a disk write.  This configuration is more suitable if the system
+# has reliable power, but may be unstable for other reasons.
+#
+CFLAGS+=-DTWE_SHUTDOWN_NOTIFICATION
+
+#
+# The module can be built to override a compiled-in driver
+#
+#CFLAGS+=-DTWE_OVERRIDE
+
 .PATH:	${.CURDIR}/../../dev/twe
 KMOD=	twe
-SRCS=	bus_if.h device_if.h pci_if.h twe.c twe_disk.c
+SRCS=	bus_if.h device_if.h pci_if.h twe.c twe_freebsd.c
+
+#CFLAGS+=-DTWE_DEBUG=0
 
 .include <bsd.kmod.mk>