diff options
Diffstat (limited to 'drivers/power/reset/xgene-reboot.c')
| -rw-r--r-- | drivers/power/reset/xgene-reboot.c | 103 | 
1 files changed, 103 insertions, 0 deletions
diff --git a/drivers/power/reset/xgene-reboot.c b/drivers/power/reset/xgene-reboot.c new file mode 100644 index 00000000000..ecd55f81b9d --- /dev/null +++ b/drivers/power/reset/xgene-reboot.c @@ -0,0 +1,103 @@ +/* + * AppliedMicro X-Gene SoC Reboot Driver + * + * Copyright (c) 2013, Applied Micro Circuits Corporation + * Author: Feng Kan <fkan@apm.com> + * Author: Loc Ho <lho@apm.com> + * + * 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; either version 2 of + * the License, or (at your option) any later version. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + * + * This driver provides system reboot functionality for APM X-Gene SoC. + * For system shutdown, this is board specify. If a board designer + * implements GPIO shutdown, use the gpio-poweroff.c driver. + */ +#include <linux/io.h> +#include <linux/of_device.h> +#include <linux/of_address.h> +#include <linux/platform_device.h> +#include <linux/stat.h> +#include <linux/slab.h> +#include <asm/system_misc.h> + +struct xgene_reboot_context { +	struct platform_device *pdev; +	void *csr; +	u32 mask; +}; + +static struct xgene_reboot_context *xgene_restart_ctx; + +static void xgene_restart(char str, const char *cmd) +{ +	struct xgene_reboot_context *ctx = xgene_restart_ctx; +	unsigned long timeout; + +	/* Issue the reboot */ +	if (ctx) +		writel(ctx->mask, ctx->csr); + +	timeout = jiffies + HZ; +	while (time_before(jiffies, timeout)) +		cpu_relax(); + +	dev_emerg(&ctx->pdev->dev, "Unable to restart system\n"); +} + +static int xgene_reboot_probe(struct platform_device *pdev) +{ +	struct xgene_reboot_context *ctx; + +	ctx = devm_kzalloc(&pdev->dev, sizeof(*ctx), GFP_KERNEL); +	if (!ctx) { +		dev_err(&pdev->dev, "out of memory for context\n"); +		return -ENODEV; +	} + +	ctx->csr = of_iomap(pdev->dev.of_node, 0); +	if (!ctx->csr) { +		devm_kfree(&pdev->dev, ctx); +		dev_err(&pdev->dev, "can not map resource\n"); +		return -ENODEV; +	} + +	if (of_property_read_u32(pdev->dev.of_node, "mask", &ctx->mask)) +		ctx->mask = 0xFFFFFFFF; + +	ctx->pdev = pdev; +	arm_pm_restart = xgene_restart; +	xgene_restart_ctx = ctx; + +	return 0; +} + +static struct of_device_id xgene_reboot_of_match[] = { +	{ .compatible = "apm,xgene-reboot" }, +	{} +}; + +static struct platform_driver xgene_reboot_driver = { +	.probe = xgene_reboot_probe, +	.driver = { +		.name = "xgene-reboot", +		.of_match_table = xgene_reboot_of_match, +	}, +}; + +static int __init xgene_reboot_init(void) +{ +	return platform_driver_register(&xgene_reboot_driver); +} +device_initcall(xgene_reboot_init);  | 
