Blackfin arch: workaround SIC_IWR1 reset bug, by keeping MDMA0/1 alwa…

…ys enabled in SIC_IWR1.

This way we ensure that reboot succeeds.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Bryan Wu <cooloney@kernel.org>

arch/blackfin/mach-common/ints-priority.c

@@ -1069,7 +1069,16 @@ int __init init_arch_irq(void)
 
 #if defined(CONFIG_BF54x) || defined(CONFIG_BF52x) || defined(CONFIG_BF561)
 	bfin_write_SIC_IWR0(IWR_DISABLE_ALL);
+#if defined(CONFIG_BF52x)
+	/* BF52x system reset does not properly reset SIC_IWR1 which
+	 * will screw up the bootrom as it relies on MDMA0/1 waking it
+	 * up from IDLE instructions.  See this report for more info:
+	 * http://blackfin.uclinux.org/gf/tracker/4323
+	 */
+	bfin_write_SIC_IWR1(IWR_ENABLE(10) | IWR_ENABLE(11));
+#else
 	bfin_write_SIC_IWR1(IWR_DISABLE_ALL);
+#endif
 # ifdef CONFIG_BF54x
 	bfin_write_SIC_IWR2(IWR_DISABLE_ALL);
 # endif

arch/blackfin/mach-common/pm.c

@@ -84,7 +84,16 @@ void bfin_pm_suspend_standby_enter(void)
 
 #if defined(CONFIG_BF54x) || defined(CONFIG_BF52x)  || defined(CONFIG_BF561)
 	bfin_write_SIC_IWR0(IWR_DISABLE_ALL);
+#if defined(CONFIG_BF52x)
+	/* BF52x system reset does not properly reset SIC_IWR1 which
+	 * will screw up the bootrom as it relies on MDMA0/1 waking it
+	 * up from IDLE instructions.  See this report for more info:
+	 * http://blackfin.uclinux.org/gf/tracker/4323
+	 */
+	bfin_write_SIC_IWR1(IWR_ENABLE(10) | IWR_ENABLE(11));
+#else
 	bfin_write_SIC_IWR1(IWR_DISABLE_ALL);
+#endif
 # ifdef CONFIG_BF54x
 	bfin_write_SIC_IWR2(IWR_DISABLE_ALL);
 # endif