linux/arch/arm/mach-mvebu/system-controller.c

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/*
* System controller support for Armada 370 and XP platforms.
*
* Copyright (C) 2012 Marvell
*
* Lior Amsalem <alior@marvell.com>
* Gregory CLEMENT <gregory.clement@free-electrons.com>
* Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
*
* This file is licensed under the terms of the GNU General Public
* License version 2. This program is licensed "as is" without any
* warranty of any kind, whether express or implied.
*
* The Armada 370 and Armada XP SoCs both have a range of
* miscellaneous registers, that do not belong to a particular device,
* but rather provide system-level features. This basic
* system-controller driver provides a device tree binding for those
* registers, and implements utility functions offering various
* features related to those registers.
*
* For now, the feature set is limited to restarting the platform by a
* soft-reset, but it might be extended in the future.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/of_address.h>
#include <linux/io.h>
static void __iomem *system_controller_base;
struct mvebu_system_controller {
u32 rstoutn_mask_offset;
u32 system_soft_reset_offset;
u32 rstoutn_mask_reset_out_en;
u32 system_soft_reset;
};
static struct mvebu_system_controller *mvebu_sc;
const struct mvebu_system_controller armada_370_xp_system_controller = {
.rstoutn_mask_offset = 0x60,
.system_soft_reset_offset = 0x64,
.rstoutn_mask_reset_out_en = 0x1,
.system_soft_reset = 0x1,
};
const struct mvebu_system_controller orion_system_controller = {
.rstoutn_mask_offset = 0x108,
.system_soft_reset_offset = 0x10c,
.rstoutn_mask_reset_out_en = 0x4,
.system_soft_reset = 0x1,
};
static struct of_device_id of_system_controller_table[] = {
{
.compatible = "marvell,orion-system-controller",
.data = (void *) &orion_system_controller,
}, {
.compatible = "marvell,armada-370-xp-system-controller",
.data = (void *) &armada_370_xp_system_controller,
},
{ /* end of list */ },
};
void mvebu_restart(char mode, const char *cmd)
{
if (!system_controller_base) {
pr_err("Cannot restart, system-controller not available: check the device tree\n");
} else {
/*
* Enable soft reset to assert RSTOUTn.
*/
writel(mvebu_sc->rstoutn_mask_reset_out_en,
system_controller_base +
mvebu_sc->rstoutn_mask_offset);
/*
* Assert soft reset.
*/
writel(mvebu_sc->system_soft_reset,
system_controller_base +
mvebu_sc->system_soft_reset_offset);
}
while (1)
;
}
static int __init mvebu_system_controller_init(void)
{
struct device_node *np;
np = of_find_matching_node(NULL, of_system_controller_table);
if (np) {
const struct of_device_id *match =
of_match_node(of_system_controller_table, np);
BUG_ON(!match);
system_controller_base = of_iomap(np, 0);
mvebu_sc = (struct mvebu_system_controller *)match->data;
}
return 0;
}
arch_initcall(mvebu_system_controller_init);