diff options
Diffstat (limited to 'kernel/drivers/power/reset/arm-versatile-reboot.c')
| -rw-r--r-- | kernel/drivers/power/reset/arm-versatile-reboot.c | 148 |
1 files changed, 148 insertions, 0 deletions
diff --git a/kernel/drivers/power/reset/arm-versatile-reboot.c b/kernel/drivers/power/reset/arm-versatile-reboot.c new file mode 100644 index 000000000..b208073c8 --- /dev/null +++ b/kernel/drivers/power/reset/arm-versatile-reboot.c @@ -0,0 +1,148 @@ +/* + * 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> + +#define INTEGRATOR_HDR_CTRL_OFFSET 0x0C +#define INTEGRATOR_HDR_LOCK_OFFSET 0x14 +#define INTEGRATOR_CM_CTRL_RESET (1 << 3) + +#define REALVIEW_SYS_LOCK_OFFSET 0x20 +#define REALVIEW_SYS_RESETCTL_OFFSET 0x40 + +/* Magic unlocking token used on all Versatile boards */ +#define VERSATILE_LOCK_VAL 0xA05F + +/* + * We detect the different syscon types from the compatible strings. + */ +enum versatile_reboot { + INTEGRATOR_REBOOT_CM, + 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,core-module-integrator", + .data = (void *)INTEGRATOR_REBOOT_CM + }, + { + .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 int versatile_reboot(struct notifier_block *this, unsigned long mode, + void *cmd) +{ + /* Unlock the reset register */ + /* Then hit reset on the different machines */ + switch (versatile_reboot_type) { + case INTEGRATOR_REBOOT_CM: + regmap_write(syscon_regmap, INTEGRATOR_HDR_LOCK_OFFSET, + VERSATILE_LOCK_VAL); + regmap_update_bits(syscon_regmap, + INTEGRATOR_HDR_CTRL_OFFSET, + INTEGRATOR_CM_CTRL_RESET, + INTEGRATOR_CM_CTRL_RESET); + break; + case REALVIEW_REBOOT_EB: + regmap_write(syscon_regmap, REALVIEW_SYS_LOCK_OFFSET, + VERSATILE_LOCK_VAL); + regmap_write(syscon_regmap, + REALVIEW_SYS_RESETCTL_OFFSET, 0x0008); + break; + case REALVIEW_REBOOT_PB1176: + regmap_write(syscon_regmap, REALVIEW_SYS_LOCK_OFFSET, + VERSATILE_LOCK_VAL); + regmap_write(syscon_regmap, + REALVIEW_SYS_RESETCTL_OFFSET, 0x0100); + break; + case REALVIEW_REBOOT_PB11MP: + case REALVIEW_REBOOT_PBA8: + regmap_write(syscon_regmap, REALVIEW_SYS_LOCK_OFFSET, + VERSATILE_LOCK_VAL); + 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_LOCK_OFFSET, + VERSATILE_LOCK_VAL); + regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET, + 0x00f0); + regmap_write(syscon_regmap, REALVIEW_SYS_RESETCTL_OFFSET, + 0x00f4); + break; + } + dsb(); + + return NOTIFY_DONE; +} + +static struct notifier_block versatile_reboot_nb = { + .notifier_call = versatile_reboot, + .priority = 192, +}; + +static int __init versatile_reboot_probe(void) +{ + const struct of_device_id *reboot_id; + struct device_node *np; + int err; + + 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); + + err = register_restart_handler(&versatile_reboot_nb); + if (err) + return err; + + pr_info("versatile reboot driver registered\n"); + return 0; +} +device_initcall(versatile_reboot_probe); |