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Diffstat (limited to 'kernel/arch/arm/mach-omap2/omap2-restart.c')
-rw-r--r--kernel/arch/arm/mach-omap2/omap2-restart.c65
1 files changed, 65 insertions, 0 deletions
diff --git a/kernel/arch/arm/mach-omap2/omap2-restart.c b/kernel/arch/arm/mach-omap2/omap2-restart.c
new file mode 100644
index 000000000..d937b2e40
--- /dev/null
+++ b/kernel/arch/arm/mach-omap2/omap2-restart.c
@@ -0,0 +1,65 @@
+/*
+ * omap2-restart.c - code common to all OMAP2xxx machines.
+ *
+ * Copyright (C) 2012 Texas Instruments
+ * Paul Walmsley
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+
+#include "soc.h"
+#include "common.h"
+#include "prm.h"
+
+/*
+ * reset_virt_prcm_set_ck, reset_sys_ck: pointers to the virt_prcm_set
+ * clock and the sys_ck. Used during the reset process
+ */
+static struct clk *reset_virt_prcm_set_ck, *reset_sys_ck;
+
+/* Reboot handling */
+
+/**
+ * omap2xxx_restart - Set DPLL to bypass mode for reboot to work
+ *
+ * Set the DPLL to bypass so that reboot completes successfully. No
+ * return value.
+ */
+void omap2xxx_restart(enum reboot_mode mode, const char *cmd)
+{
+ u32 rate;
+
+ rate = clk_get_rate(reset_sys_ck);
+ clk_set_rate(reset_virt_prcm_set_ck, rate);
+
+ /* XXX Should save the cmd argument for use after the reboot */
+
+ omap_prm_reset_system();
+}
+
+/**
+ * omap2xxx_common_look_up_clks_for_reset - look up clocks needed for restart
+ *
+ * Some clocks need to be looked up in advance for the SoC restart
+ * operation to work - see omap2xxx_restart(). Returns -EINVAL upon
+ * error or 0 upon success.
+ */
+static int __init omap2xxx_common_look_up_clks_for_reset(void)
+{
+ reset_virt_prcm_set_ck = clk_get(NULL, "virt_prcm_set");
+ if (IS_ERR(reset_virt_prcm_set_ck))
+ return -EINVAL;
+
+ reset_sys_ck = clk_get(NULL, "sys_ck");
+ if (IS_ERR(reset_sys_ck))
+ return -EINVAL;
+
+ return 0;
+}
+omap_core_initcall(omap2xxx_common_look_up_clks_for_reset);