kern/173584: [PATCH] [cxgbe] Add hw.cxgbe.force_firmware_install tunable to force firmware "updates" at module load

[Garrett Cooper]

>Number:         173584
>Category:       kern
>Synopsis:       [PATCH] [cxgbe] Add hw.cxgbe.force_firmware_install tunable to force firmware "updates" at module load
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Nov 12 19:20:00 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Garrett Cooper
>Release:        9.1-STABLE
>Organization:
EMC Isilon
>Environment:
FreeBSD wf158.west.isilon.com 9.1-PRERELEASE FreeBSD 9.1-PRERELEASE #2: Tue Nov  6 14:00:42 PST 2012     root at wf158.west.isilon.com:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
The attached patch adds a tunable  which forces a firmware update in order to ensure that when the driver is loaded, if it's running a newer version of firmware it can be downgraded to an older version. Example:

# kenv hw.cxgbe.force_firmware_install=1
# kldload if_cxgbe
# sysctl dev.t4nex.0.firmware_version
dev.t4nex.0.firmware_version: 1.6.2.0

The firmware version provided on the card was newer before (1.7.x IIRC).
>How-To-Repeat:

>Fix:


Patch attached with submission follows:

Index: sys/dev/cxgbe/t4_main.c
===================================================================
--- sys/dev/cxgbe/t4_main.c	(revision 242655)
+++ sys/dev/cxgbe/t4_main.c	(working copy)
@@ -234,6 +234,9 @@
 static int t4_fcoecaps_allowed = 0;
 TUNABLE_INT("hw.cxgbe.fcoecaps_allowed", &t4_fcoecaps_allowed);
 
+static int t4_force_firmware_install = 0;
+TUNABLE_INT("hw.cxgbe.force_firmware_install", &t4_force_firmware_install);
+
 struct intrs_and_queues {
 	int intr_type;		/* INTx, MSI, or MSI-X */
 	int nirq;		/* Number of vectors */
@@ -1576,9 +1579,10 @@
 		/*
 		 * Always upgrade, even for minor/micro/build mismatches.
 		 * Downgrade only for a major version mismatch or if
-		 * force_firmware_install was specified.
+		 * t4_force_firmware_install was specified.
 		 */
-		if (fw != NULL && (rc < 0 || v > sc->params.fw_vers)) {
+		if (fw != NULL &&
+		    (t4_force_firmware_install || rc < 0 || v > sc->params.fw_vers)) {
 			device_printf(sc->dev,
 			    "installing firmware %d.%d.%d.%d on card.\n",
 			    G_FW_HDR_FW_VER_MAJOR(v), G_FW_HDR_FW_VER_MINOR(v),


>Release-Note:
>Audit-Trail:
>Unformatted: