89 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
		
		
			
		
	
	
			89 lines
		
	
	
	
		
			2.4 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
|   | /*
 | ||
|  |  * 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); |