/* * Copyright (C) 2013 Broadcom Corporation * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License as * published by the Free Software Foundation version 2. * * This program is distributed "as is" WITHOUT ANY WARRANTY of any * kind, whether express or implied; without even the implied warranty * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. */ #include <linux/bitops.h> #include <linux/device.h> #include <linux/errno.h> #include <linux/init.h> #include <linux/io.h> #include <linux/jiffies.h> #include <linux/notifier.h> #include <linux/of_address.h> #include <linux/of_irq.h> #include <linux/of_platform.h> #include <linux/platform_device.h> #include <linux/printk.h> #include <linux/reboot.h> #include <linux/regmap.h> #include <linux/smp.h> #include <linux/mfd/syscon.h> #define RESET_SOURCE_ENABLE_REG 1 #define SW_MASTER_RESET_REG 2 static struct regmap *regmap; static u32 rst_src_en; static u32 sw_mstr_rst; struct reset_reg_mask { u32 rst_src_en_mask; u32 sw_mstr_rst_mask; }; static const struct reset_reg_mask *reset_masks; static int brcmstb_restart_handler(struct notifier_block *this, unsigned long mode, void *cmd) { int rc; u32 tmp; rc = regmap_write(regmap, rst_src_en, reset_masks->rst_src_en_mask); if (rc) { pr_err("failed to write rst_src_en (%d)\n", rc); return NOTIFY_DONE; } rc = regmap_read(regmap, rst_src_en, &tmp); if (rc) { pr_err("failed to read rst_src_en (%d)\n", rc); return NOTIFY_DONE; } rc = regmap_write(regmap, sw_mstr_rst, reset_masks->sw_mstr_rst_mask); if (rc) { pr_err("failed to write sw_mstr_rst (%d)\n", rc); return NOTIFY_DONE; } rc = regmap_read(regmap, sw_mstr_rst, &tmp); if (rc) { pr_err("failed to read sw_mstr_rst (%d)\n", rc); return NOTIFY_DONE; } while (1) ; return NOTIFY_DONE; } static struct notifier_block brcmstb_restart_nb = { .notifier_call = brcmstb_restart_handler, .priority = 128, }; static const struct reset_reg_mask reset_bits_40nm = { .rst_src_en_mask = BIT(0), .sw_mstr_rst_mask = BIT(0), }; static const struct reset_reg_mask reset_bits_65nm = { .rst_src_en_mask = BIT(3), .sw_mstr_rst_mask = BIT(31), }; static const struct of_device_id of_match[] = { { .compatible = "brcm,brcmstb-reboot", .data = &reset_bits_40nm }, { .compatible = "brcm,bcm7038-reboot", .data = &reset_bits_65nm }, {}, }; static int brcmstb_reboot_probe(struct platform_device *pdev) { int rc; struct device_node *np = pdev->dev.of_node; const struct of_device_id *of_id; of_id = of_match_node(of_match, np); if (!of_id) { pr_err("failed to look up compatible string\n"); return -EINVAL; } reset_masks = of_id->data; regmap = syscon_regmap_lookup_by_phandle(np, "syscon"); if (IS_ERR(regmap)) { pr_err("failed to get syscon phandle\n"); return -EINVAL; } rc = of_property_read_u32_index(np, "syscon", RESET_SOURCE_ENABLE_REG, &rst_src_en); if (rc) { pr_err("can't get rst_src_en offset (%d)\n", rc); return -EINVAL; } rc = of_property_read_u32_index(np, "syscon", SW_MASTER_RESET_REG, &sw_mstr_rst); if (rc) { pr_err("can't get sw_mstr_rst offset (%d)\n", rc); return -EINVAL; } rc = register_restart_handler(&brcmstb_restart_nb); if (rc) dev_err(&pdev->dev, "cannot register restart handler (err=%d)\n", rc); return rc; } static struct platform_driver brcmstb_reboot_driver = { .probe = brcmstb_reboot_probe, .driver = { .name = "brcmstb-reboot", .of_match_table = of_match, }, }; static int __init brcmstb_reboot_init(void) { return platform_driver_probe(&brcmstb_reboot_driver, brcmstb_reboot_probe); } subsys_initcall(brcmstb_reboot_init);