diff --git a/target/linux/brcm63xx/files/arch/mips/bcm63xx/setup.c b/target/linux/brcm63xx/files/arch/mips/bcm63xx/setup.c
index 95760ae44..6d1ce6442 100644
--- a/target/linux/brcm63xx/files/arch/mips/bcm63xx/setup.c
+++ b/target/linux/brcm63xx/files/arch/mips/bcm63xx/setup.c
@@ -73,7 +73,9 @@ void bcm63xx_machine_reboot(void)
 		bcm6348_a1_reboot();
 
 	printk(KERN_INFO "triggering watchdog soft-reset...\n");
-	bcm_perf_writel(SYS_PLL_SOFT_RESET, PERF_SYS_PLL_CTL_REG);
+	reg = bcm_perf_readl(PERF_SYS_PLL_CTL_REG);
+	reg |= SYS_PLL_SOFT_RESET;
+	bcm_perf_writel(reg, PERF_SYS_PLL_CTL_REG);
 	while (1);
 }