167778e0eSLoc Ho /* 267778e0eSLoc Ho * AppliedMicro X-Gene SoC Reboot Driver 367778e0eSLoc Ho * 467778e0eSLoc Ho * Copyright (c) 2013, Applied Micro Circuits Corporation 567778e0eSLoc Ho * Author: Feng Kan <fkan@apm.com> 667778e0eSLoc Ho * Author: Loc Ho <lho@apm.com> 767778e0eSLoc Ho * 867778e0eSLoc Ho * This program is free software; you can redistribute it and/or 967778e0eSLoc Ho * modify it under the terms of the GNU General Public License as 1067778e0eSLoc Ho * published by the Free Software Foundation; either version 2 of 1167778e0eSLoc Ho * the License, or (at your option) any later version. 1267778e0eSLoc Ho * 1367778e0eSLoc Ho * This program is distributed in the hope that it will be useful, 1467778e0eSLoc Ho * but WITHOUT ANY WARRANTY; without even the implied warranty of 1567778e0eSLoc Ho * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1667778e0eSLoc Ho * GNU General Public License for more details. 1767778e0eSLoc Ho * 1867778e0eSLoc Ho * You should have received a copy of the GNU General Public License 1967778e0eSLoc Ho * along with this program; if not, write to the Free Software 2067778e0eSLoc Ho * Foundation, Inc., 59 Temple Place, Suite 330, Boston, 2167778e0eSLoc Ho * MA 02111-1307 USA 2267778e0eSLoc Ho * 2367778e0eSLoc Ho * This driver provides system reboot functionality for APM X-Gene SoC. 2467778e0eSLoc Ho * For system shutdown, this is board specify. If a board designer 2567778e0eSLoc Ho * implements GPIO shutdown, use the gpio-poweroff.c driver. 2667778e0eSLoc Ho */ 27745e1976SGuenter Roeck #include <linux/delay.h> 2867778e0eSLoc Ho #include <linux/io.h> 298f57f231SGuenter Roeck #include <linux/notifier.h> 3067778e0eSLoc Ho #include <linux/of_device.h> 3167778e0eSLoc Ho #include <linux/of_address.h> 3267778e0eSLoc Ho #include <linux/platform_device.h> 338f57f231SGuenter Roeck #include <linux/reboot.h> 3467778e0eSLoc Ho #include <linux/stat.h> 3567778e0eSLoc Ho #include <linux/slab.h> 3667778e0eSLoc Ho 3767778e0eSLoc Ho struct xgene_reboot_context { 3843160718SGuenter Roeck struct device *dev; 3967778e0eSLoc Ho void *csr; 4067778e0eSLoc Ho u32 mask; 418f57f231SGuenter Roeck struct notifier_block restart_handler; 4267778e0eSLoc Ho }; 4367778e0eSLoc Ho 448f57f231SGuenter Roeck static int xgene_restart_handler(struct notifier_block *this, 458f57f231SGuenter Roeck unsigned long mode, void *cmd) 4667778e0eSLoc Ho { 478f57f231SGuenter Roeck struct xgene_reboot_context *ctx = 488f57f231SGuenter Roeck container_of(this, struct xgene_reboot_context, 498f57f231SGuenter Roeck restart_handler); 5067778e0eSLoc Ho 5167778e0eSLoc Ho /* Issue the reboot */ 5267778e0eSLoc Ho writel(ctx->mask, ctx->csr); 5367778e0eSLoc Ho 54745e1976SGuenter Roeck mdelay(1000); 5567778e0eSLoc Ho 5643160718SGuenter Roeck dev_emerg(ctx->dev, "Unable to restart system\n"); 578f57f231SGuenter Roeck 588f57f231SGuenter Roeck return NOTIFY_DONE; 5967778e0eSLoc Ho } 6067778e0eSLoc Ho 6167778e0eSLoc Ho static int xgene_reboot_probe(struct platform_device *pdev) 6267778e0eSLoc Ho { 6367778e0eSLoc Ho struct xgene_reboot_context *ctx; 6443160718SGuenter Roeck struct device *dev = &pdev->dev; 658f57f231SGuenter Roeck int err; 6667778e0eSLoc Ho 6743160718SGuenter Roeck ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL); 68ef288f9fSGuenter Roeck if (!ctx) 69ef288f9fSGuenter Roeck return -ENOMEM; 7067778e0eSLoc Ho 7143160718SGuenter Roeck ctx->csr = of_iomap(dev->of_node, 0); 7267778e0eSLoc Ho if (!ctx->csr) { 7343160718SGuenter Roeck dev_err(dev, "can not map resource\n"); 7467778e0eSLoc Ho return -ENODEV; 7567778e0eSLoc Ho } 7667778e0eSLoc Ho 7743160718SGuenter Roeck if (of_property_read_u32(dev->of_node, "mask", &ctx->mask)) 7867778e0eSLoc Ho ctx->mask = 0xFFFFFFFF; 7967778e0eSLoc Ho 8043160718SGuenter Roeck ctx->dev = dev; 818f57f231SGuenter Roeck ctx->restart_handler.notifier_call = xgene_restart_handler; 828f57f231SGuenter Roeck ctx->restart_handler.priority = 128; 838f57f231SGuenter Roeck err = register_restart_handler(&ctx->restart_handler); 848f57f231SGuenter Roeck if (err) 858f57f231SGuenter Roeck dev_err(dev, "cannot register restart handler (err=%d)\n", err); 8667778e0eSLoc Ho 878f57f231SGuenter Roeck return err; 8867778e0eSLoc Ho } 8967778e0eSLoc Ho 908fb08855SFabian Frederick static const struct of_device_id xgene_reboot_of_match[] = { 9167778e0eSLoc Ho { .compatible = "apm,xgene-reboot" }, 9267778e0eSLoc Ho {} 9367778e0eSLoc Ho }; 9467778e0eSLoc Ho 9567778e0eSLoc Ho static struct platform_driver xgene_reboot_driver = { 9667778e0eSLoc Ho .probe = xgene_reboot_probe, 9767778e0eSLoc Ho .driver = { 9867778e0eSLoc Ho .name = "xgene-reboot", 9967778e0eSLoc Ho .of_match_table = xgene_reboot_of_match, 10067778e0eSLoc Ho }, 10167778e0eSLoc Ho }; 10267778e0eSLoc Ho 10367778e0eSLoc Ho static int __init xgene_reboot_init(void) 10467778e0eSLoc Ho { 10567778e0eSLoc Ho return platform_driver_register(&xgene_reboot_driver); 10667778e0eSLoc Ho } 10767778e0eSLoc Ho device_initcall(xgene_reboot_init); 108