From: Anders Berg <anders.berg@xxxxxxx> Add Axxia (AXM55xx) SoC system reset driver. This driver handles only system reboot (and not power-off). Signed-off-by: Anders Berg <anders.berg@xxxxxxx> Cc: Dmitry Eremin-Solenikov <dbaryshkov@xxxxxxxxx> Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx> Acked-by: Linus Walleij <linus.walleij@xxxxxxxxxx> --- .../bindings/power_supply/axxia-reset.txt | 20 +++++ drivers/power/reset/Kconfig | 8 ++ drivers/power/reset/Makefile | 1 + drivers/power/reset/axxia-reset.c | 88 ++++++++++++++++++++++ 4 files changed, 117 insertions(+) create mode 100644 Documentation/devicetree/bindings/power_supply/axxia-reset.txt create mode 100644 drivers/power/reset/axxia-reset.c diff --git a/Documentation/devicetree/bindings/power_supply/axxia-reset.txt b/Documentation/devicetree/bindings/power_supply/axxia-reset.txt new file mode 100644 index 0000000..47e720d --- /dev/null +++ b/Documentation/devicetree/bindings/power_supply/axxia-reset.txt @@ -0,0 +1,20 @@ +Axxia Restart Driver + +This driver can do reset of the Axxia SoC. It uses the registers in the syscon +block to initiate a chip reset. + +Required Properties: + -compatible: "lsi,axm55xx-reset" + -syscon: phandle to the syscon node. + +Example: + + syscon: syscon@2010030000 { + compatible = "lsi,axxia-syscon", "syscon"; + reg = <0x20 0x10030000 0 0x2000>; + }; + + reset: reset@2010031000 { + compatible = "lsi,axm55xx-reset"; + syscon = <&syscon>; + }; diff --git a/drivers/power/reset/Kconfig b/drivers/power/reset/Kconfig index fa0e4e0..49b46e6 100644 --- a/drivers/power/reset/Kconfig +++ b/drivers/power/reset/Kconfig @@ -12,6 +12,14 @@ config POWER_RESET_AS3722 help This driver supports turning off board via a ams AS3722 power-off. +config POWER_RESET_AXXIA + bool "LSI Axxia reset driver" + depends on POWER_RESET && ARCH_AXXIA + help + This driver supports restart for Axxia SoC. + + Say Y if you have an Axxia family SoC. + config POWER_RESET_GPIO bool "GPIO power-off driver" depends on OF_GPIO && POWER_RESET diff --git a/drivers/power/reset/Makefile b/drivers/power/reset/Makefile index a5b4a77..16c0516 100644 --- a/drivers/power/reset/Makefile +++ b/drivers/power/reset/Makefile @@ -1,4 +1,5 @@ obj-$(CONFIG_POWER_RESET_AS3722) += as3722-poweroff.o +obj-$(CONFIG_POWER_RESET_AXXIA) += axxia-reset.o obj-$(CONFIG_POWER_RESET_GPIO) += gpio-poweroff.o obj-$(CONFIG_POWER_RESET_MSM) += msm-poweroff.o obj-$(CONFIG_POWER_RESET_QNAP) += qnap-poweroff.o diff --git a/drivers/power/reset/axxia-reset.c b/drivers/power/reset/axxia-reset.c new file mode 100644 index 0000000..3b1f8d6 --- /dev/null +++ b/drivers/power/reset/axxia-reset.c @@ -0,0 +1,88 @@ +/* + * Reset driver for Axxia devices + * + * Copyright (C) 2014 LSI + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 and + * only version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ +#include <linux/init.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/kernel.h> +#include <linux/mfd/syscon.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/reboot.h> +#include <linux/regmap.h> + +#include <asm/system_misc.h> + + +#define SC_CRIT_WRITE_KEY 0x1000 +#define SC_LATCH_ON_RESET 0x1004 +#define SC_RESET_CONTROL 0x1008 +#define RSTCTL_RST_ZERO (1<<3) +#define RSTCTL_RST_FAB (1<<2) +#define RSTCTL_RST_CHIP (1<<1) +#define RSTCTL_RST_SYS (1<<0) +#define SC_EFUSE_INT_STATUS 0x180c +#define EFUSE_READ_DONE (1<<31) + +static struct regmap *syscon; + +static void do_axxia_restart(enum reboot_mode reboot_mode, const char *cmd) +{ + /* Access Key (0xab) */ + regmap_write(syscon, SC_CRIT_WRITE_KEY, 0xab); + /* Select internal boot from 0xffff0000 */ + regmap_write(syscon, SC_LATCH_ON_RESET, 0x00000040); + /* Assert ResetReadDone (to avoid hanging in boot ROM) */ + regmap_write(syscon, SC_EFUSE_INT_STATUS, EFUSE_READ_DONE); + /* Assert chip reset */ + regmap_update_bits(syscon, SC_RESET_CONTROL, + RSTCTL_RST_CHIP, RSTCTL_RST_CHIP); +} + +static int axxia_reset_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + + syscon = syscon_regmap_lookup_by_phandle(dev->of_node, "syscon"); + if (IS_ERR(syscon)) { + pr_err("%s: syscon lookup failed\n", dev->of_node->name); + return PTR_ERR(syscon); + } + + arm_pm_restart = do_axxia_restart; + + return 0; +} + +static const struct of_device_id of_axxia_reset_match[] = { + { .compatible = "lsi,axm55xx-reset", }, + {}, +}; +MODULE_DEVICE_TABLE(of, of_axxia_reset_match); + +static struct platform_driver axxia_reset_driver = { + .probe = axxia_reset_probe, + .driver = { + .name = "axxia-reset", + .of_match_table = of_match_ptr(of_axxia_reset_match), + }, +}; + +static int __init axxia_reset_init(void) +{ + return platform_driver_register(&axxia_reset_driver); +} +device_initcall(axxia_reset_init); -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html