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path: root/drivers/power/reset/arm-versatile-reboot.c
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Diffstat (limited to 'drivers/power/reset/arm-versatile-reboot.c')
-rw-r--r--drivers/power/reset/arm-versatile-reboot.c111
1 files changed, 111 insertions, 0 deletions
diff --git a/drivers/power/reset/arm-versatile-reboot.c b/drivers/power/reset/arm-versatile-reboot.c
new file mode 100644
index 00000000000..5b08bffcf1a
--- /dev/null
+++ b/drivers/power/reset/arm-versatile-reboot.c
@@ -0,0 +1,111 @@
+/*
+ * Copyright (C) 2014 Linaro Ltd.
+ *
+ * Author: Linus Walleij <linus.walleij@linaro.org>
+ *
+ * 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/init.h>
+#include <linux/mfd/syscon.h>
+#include <linux/reboot.h>
+#include <linux/regmap.h>
+#include <linux/of.h>
+#include <asm/system_misc.h>
+
+#define REALVIEW_SYS_LOCK_OFFSET 0x20
+#define REALVIEW_SYS_LOCK_VAL 0xA05F
+#define REALVIEW_SYS_RESETCTL_OFFSET 0x40
+
+/*
+ * We detect the different syscon types from the compatible strings.
+ */
+enum versatile_reboot {
+ REALVIEW_REBOOT_EB,
+ REALVIEW_REBOOT_PB1176,
+ REALVIEW_REBOOT_PB11MP,
+ REALVIEW_REBOOT_PBA8,
+ REALVIEW_REBOOT_PBX,
+};
+
+/* Pointer to the system controller */
+static struct regmap *syscon_regmap;
+static enum versatile_reboot versatile_reboot_type;
+
+static const struct of_device_id versatile_reboot_of_match[] = {
+ {
+ .compatible = "arm,realview-eb-syscon",
+ .data = (void *)REALVIEW_REBOOT_EB,
+ },
+ {
+ .compatible = "arm,realview-pb1176-syscon",
+ .data = (void *)REALVIEW_REBOOT_PB1176,
+ },
+ {
+ .compatible = "arm,realview-pb11mp-syscon",
+ .data = (void *)REALVIEW_REBOOT_PB11MP,
+ },
+ {
+ .compatible = "arm,realview-pba8-syscon",
+ .data = (void *)REALVIEW_REBOOT_PBA8,
+ },
+ {
+ .compatible = "arm,realview-pbx-syscon",
+ .data = (void *)REALVIEW_REBOOT_PBX,
+ },
+};
+
+static void versatile_reboot(enum reboot_mode mode, const char *cmd)
+{
+ /* Unlock the reset register */
+ regmap_write(syscon_regmap, REALVIEW_SYS_LOCK_OFFSET,
+ REALVIEW_SYS_LOCK_VAL);
+ /* Then hit reset on the different machines */
+ switch (versatile_reboot_type) {
+ case REALVIEW_REBOOT_EB:
+ regmap_write(syscon_regmap,
+ REALVIEW_SYS_RESETCTL_OFFSET, 0x0008);
+ break;
+ case REALVIEW_REBOOT_PB1176:
+ regmap_write(syscon_regmap,
+ REALVIEW_SYS_RESETCTL_OFFSET, 0x0100);
+ break;
+ case REALVIEW_REBOOT_PB11MP:
+ case REALVIEW_REBOOT_PBA8:
+ regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
+ 0x0000);
+ regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
+ 0x0004);
+ break;
+ case REALVIEW_REBOOT_PBX:
+ regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
+ 0x00f0);
+ regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET,
+ 0x00f4);
+ break;
+ }
+ dsb();
+}
+
+static int __init versatile_reboot_probe(void)
+{
+ const struct of_device_id *reboot_id;
+ struct device_node *np;
+
+ np = of_find_matching_node_and_match(NULL, versatile_reboot_of_match,
+ &reboot_id);
+ if (!np)
+ return -ENODEV;
+ versatile_reboot_type = (enum versatile_reboot)reboot_id->data;
+
+ syscon_regmap = syscon_node_to_regmap(np);
+ if (IS_ERR(syscon_regmap))
+ return PTR_ERR(syscon_regmap);
+
+ arm_pm_restart = versatile_reboot;
+ pr_info("versatile reboot driver registered\n");
+ return 0;
+}
+device_initcall(versatile_reboot_probe);