svn commit: r336072 - head/sys/arm/freescale/imx

[Ian Lepore]

Author: ian
Date: Sat Jul  7 19:03:38 2018
New Revision: 336072
URL: https://svnweb.freebsd.org/changeset/base/336072

Log:
  Correctly calculate the value to put in the imx wdog countdown register.
  
  The correct value is seconds*2-1.  The code was using just seconds*2, which
  led to being off by a half-second -- usually not a big deal, except when the
  value was the max (128) it overflowed so zero would get written to the
  countdown register, which equates to a timeout of a half second.

Modified:
  head/sys/arm/freescale/imx/imx_wdog.c

Modified: head/sys/arm/freescale/imx/imx_wdog.c
==============================================================================
--- head/sys/arm/freescale/imx/imx_wdog.c	Sat Jul  7 17:58:20 2018	(r336071)
+++ head/sys/arm/freescale/imx/imx_wdog.c	Sat Jul  7 19:03:38 2018	(r336072)
@@ -118,8 +118,7 @@ imx_watchdog(void *arg, u_int cmd, int *error)
 				sc->sc_timeout = timeout;
 				reg = RD2(sc, WDOG_CR_REG);
 				reg &= ~WDOG_CR_WT_MASK;
-				reg |= (timeout << (WDOG_CR_WT_SHIFT + 1)) &
-				    WDOG_CR_WT_MASK;
+				reg |= ((2 * timeout - 1) << WDOG_CR_WT_SHIFT);
 				WR2(sc, WDOG_CR_REG, reg | WDOG_CR_WDE);
 			}
 			/* Refresh counter */