11a59d1b8SThomas Gleixner // SPDX-License-Identifier: GPL-2.0-or-later
267778e0eSLoc Ho /*
367778e0eSLoc Ho * AppliedMicro X-Gene SoC Reboot Driver
467778e0eSLoc Ho *
567778e0eSLoc Ho * Copyright (c) 2013, Applied Micro Circuits Corporation
667778e0eSLoc Ho * Author: Feng Kan <fkan@apm.com>
767778e0eSLoc Ho * Author: Loc Ho <lho@apm.com>
867778e0eSLoc Ho *
967778e0eSLoc Ho * This driver provides system reboot functionality for APM X-Gene SoC.
1067778e0eSLoc Ho * For system shutdown, this is board specify. If a board designer
1167778e0eSLoc Ho * implements GPIO shutdown, use the gpio-poweroff.c driver.
1267778e0eSLoc Ho */
13745e1976SGuenter Roeck #include <linux/delay.h>
1467778e0eSLoc Ho #include <linux/io.h>
158f57f231SGuenter Roeck #include <linux/notifier.h>
16*2ce8284cSRob Herring #include <linux/of.h>
1767778e0eSLoc Ho #include <linux/of_address.h>
1867778e0eSLoc Ho #include <linux/platform_device.h>
198f57f231SGuenter Roeck #include <linux/reboot.h>
2067778e0eSLoc Ho #include <linux/stat.h>
2167778e0eSLoc Ho #include <linux/slab.h>
2267778e0eSLoc Ho
2367778e0eSLoc Ho struct xgene_reboot_context {
2443160718SGuenter Roeck struct device *dev;
2567778e0eSLoc Ho void *csr;
2667778e0eSLoc Ho u32 mask;
278f57f231SGuenter Roeck struct notifier_block restart_handler;
2867778e0eSLoc Ho };
2967778e0eSLoc Ho
xgene_restart_handler(struct notifier_block * this,unsigned long mode,void * cmd)308f57f231SGuenter Roeck static int xgene_restart_handler(struct notifier_block *this,
318f57f231SGuenter Roeck unsigned long mode, void *cmd)
3267778e0eSLoc Ho {
338f57f231SGuenter Roeck struct xgene_reboot_context *ctx =
348f57f231SGuenter Roeck container_of(this, struct xgene_reboot_context,
358f57f231SGuenter Roeck restart_handler);
3667778e0eSLoc Ho
3767778e0eSLoc Ho /* Issue the reboot */
3867778e0eSLoc Ho writel(ctx->mask, ctx->csr);
3967778e0eSLoc Ho
40745e1976SGuenter Roeck mdelay(1000);
4167778e0eSLoc Ho
4243160718SGuenter Roeck dev_emerg(ctx->dev, "Unable to restart system\n");
438f57f231SGuenter Roeck
448f57f231SGuenter Roeck return NOTIFY_DONE;
4567778e0eSLoc Ho }
4667778e0eSLoc Ho
xgene_reboot_probe(struct platform_device * pdev)4767778e0eSLoc Ho static int xgene_reboot_probe(struct platform_device *pdev)
4867778e0eSLoc Ho {
4967778e0eSLoc Ho struct xgene_reboot_context *ctx;
5043160718SGuenter Roeck struct device *dev = &pdev->dev;
518f57f231SGuenter Roeck int err;
5267778e0eSLoc Ho
5343160718SGuenter Roeck ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
54ef288f9fSGuenter Roeck if (!ctx)
55ef288f9fSGuenter Roeck return -ENOMEM;
5667778e0eSLoc Ho
5743160718SGuenter Roeck ctx->csr = of_iomap(dev->of_node, 0);
5867778e0eSLoc Ho if (!ctx->csr) {
5943160718SGuenter Roeck dev_err(dev, "can not map resource\n");
6067778e0eSLoc Ho return -ENODEV;
6167778e0eSLoc Ho }
6267778e0eSLoc Ho
6343160718SGuenter Roeck if (of_property_read_u32(dev->of_node, "mask", &ctx->mask))
6467778e0eSLoc Ho ctx->mask = 0xFFFFFFFF;
6567778e0eSLoc Ho
6643160718SGuenter Roeck ctx->dev = dev;
678f57f231SGuenter Roeck ctx->restart_handler.notifier_call = xgene_restart_handler;
688f57f231SGuenter Roeck ctx->restart_handler.priority = 128;
698f57f231SGuenter Roeck err = register_restart_handler(&ctx->restart_handler);
70896af83eSArvind Yadav if (err) {
71896af83eSArvind Yadav iounmap(ctx->csr);
728f57f231SGuenter Roeck dev_err(dev, "cannot register restart handler (err=%d)\n", err);
73896af83eSArvind Yadav }
7467778e0eSLoc Ho
758f57f231SGuenter Roeck return err;
7667778e0eSLoc Ho }
7767778e0eSLoc Ho
788fb08855SFabian Frederick static const struct of_device_id xgene_reboot_of_match[] = {
7967778e0eSLoc Ho { .compatible = "apm,xgene-reboot" },
8067778e0eSLoc Ho {}
8167778e0eSLoc Ho };
8267778e0eSLoc Ho
8367778e0eSLoc Ho static struct platform_driver xgene_reboot_driver = {
8467778e0eSLoc Ho .probe = xgene_reboot_probe,
8567778e0eSLoc Ho .driver = {
8667778e0eSLoc Ho .name = "xgene-reboot",
8767778e0eSLoc Ho .of_match_table = xgene_reboot_of_match,
8867778e0eSLoc Ho },
8967778e0eSLoc Ho };
9067778e0eSLoc Ho
xgene_reboot_init(void)9167778e0eSLoc Ho static int __init xgene_reboot_init(void)
9267778e0eSLoc Ho {
9367778e0eSLoc Ho return platform_driver_register(&xgene_reboot_driver);
9467778e0eSLoc Ho }
9567778e0eSLoc Ho device_initcall(xgene_reboot_init);
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