powerpc/mpc5121: Add machine restart support

Add reset module registers representation and
machine restart callback for mpc5121 platform.
Signed-off-by: Piotr Ziecik <kosmo@semihalf.com>
Signed-off-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

arch/powerpc/include/asm/mpc5121.h

+/*
+ * MPC5121 Prototypes and definitions
+ *
+ * This file is licensed under the terms of the GNU General Public
+ * License version 2.
+ */
+
+#ifndef __ASM_POWERPC_MPC5121_H__
+#define __ASM_POWERPC_MPC5121_H__
+
+/* MPC512x Reset module registers */
+struct mpc512x_reset_module {
+	u32	rcwlr;	/* Reset Configuration Word Low Register */
+	u32	rcwhr;	/* Reset Configuration Word High Register */
+	u32	reserved1;
+	u32	reserved2;
+	u32	rsr;	/* Reset Status Register */
+	u32	rmr;	/* Reset Mode Register */
+	u32	rpr;	/* Reset Protection Register */
+	u32	rcr;	/* Reset Control Register */
+	u32	rcer;	/* Reset Control Enable Register */
+};
+
+#endif /* __ASM_POWERPC_MPC5121_H__ */

arch/powerpc/platforms/512x/mpc5121_ads.c

@@ -68,4 +68,5 @@ define_machine(mpc5121_ads) {
 	.init_IRQ		= mpc5121_ads_init_IRQ,
 	.get_irq		= ipic_get_irq,
 	.calibrate_decr		= generic_calibrate_decr,
+	.restart		= mpc512x_restart,
 };

arch/powerpc/platforms/512x/mpc5121_generic.c

@@ -55,4 +55,5 @@ define_machine(mpc5121_generic) {
 	.init_IRQ		= mpc512x_init_IRQ,
 	.get_irq		= ipic_get_irq,
 	.calibrate_decr		= generic_calibrate_decr,
+	.restart		= mpc512x_restart,
 };

arch/powerpc/platforms/512x/mpc512x.h

@@ -15,4 +15,5 @@ extern void __init mpc512x_init_IRQ(void);
 extern void __init mpc512x_init(void);
 extern int __init mpc5121_clk_init(void);
 void __init mpc512x_declare_of_platform_devices(void);
+extern void mpc512x_restart(char *cmd);
 #endif				/* __MPC512X_H__ */

arch/powerpc/platforms/512x/mpc512x_shared.c

@@ -21,9 +21,38 @@
 #include <asm/ipic.h>
 #include <asm/prom.h>
 #include <asm/time.h>
+#include <asm/mpc5121.h>
 
 #include "mpc512x.h"
 
+static struct mpc512x_reset_module __iomem *reset_module_base;
+
+static void __init mpc512x_restart_init(void)
+{
+	struct device_node *np;
+
+	np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-reset");
+	if (!np)
+		return;
+
+	reset_module_base = of_iomap(np, 0);
+	of_node_put(np);
+}
+
+void mpc512x_restart(char *cmd)
+{
+	if (reset_module_base) {
+		/* Enable software reset "RSTE" */
+		out_be32(&reset_module_base->rpr, 0x52535445);
+		/* Set software hard reset */
+		out_be32(&reset_module_base->rcr, 0x2);
+	} else {
+		pr_err("Restart module not mapped.\n");
+	}
+	for (;;)
+		;
+}
+
 void __init mpc512x_init_IRQ(void)
 {
 	struct device_node *np;
@@ -62,4 +91,5 @@ void __init mpc512x_init(void)
 {
 	mpc512x_declare_of_platform_devices();
 	mpc5121_clk_init();
+	mpc512x_restart_init();
 }