rcar-rst.c
/*
* R-Car Gen1 RESET/WDT, R-Car Gen2, Gen3, and RZ/G RST Driver
*
* Copyright (C) 2016 Glider bvba
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/err.h>
#include <linux/io.h>
#include <linux/of_address.h>
#include <linux/soc/renesas/rcar-rst.h>
struct rst_config {
unsigned int modemr; /* Mode Monitoring Register Offset */
};
static const struct rst_config rcar_rst_gen1 __initconst = {
.modemr = 0x20,
};
static const struct rst_config rcar_rst_gen2 __initconst = {
.modemr = 0x60,
};
static const struct of_device_id rcar_rst_matches[] __initconst = {
/* RZ/G is handled like R-Car Gen2 */
{ .compatible = "renesas,r8a7743-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a7745-rst", .data = &rcar_rst_gen2 },
/* R-Car Gen1 */
{ .compatible = "renesas,r8a7778-reset-wdt", .data = &rcar_rst_gen1 },
{ .compatible = "renesas,r8a7779-reset-wdt", .data = &rcar_rst_gen1 },
/* R-Car Gen2 */
{ .compatible = "renesas,r8a7790-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a7791-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a7792-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a7793-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a7794-rst", .data = &rcar_rst_gen2 },
/* R-Car Gen3 is handled like R-Car Gen2 */
{ .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a77970-rst", .data = &rcar_rst_gen2 },
{ .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen2 },
{ /* sentinel */ }
};
static void __iomem *rcar_rst_base __initdata;
static u32 saved_mode __initdata;
static int __init rcar_rst_init(void)
{
const struct of_device_id *match;
const struct rst_config *cfg;
struct device_node *np;
void __iomem *base;
int error = 0;
np = of_find_matching_node_and_match(NULL, rcar_rst_matches, &match);
if (!np)
return -ENODEV;
base = of_iomap(np, 0);
if (!base) {
pr_warn("%pOF: Cannot map regs\n", np);
error = -ENOMEM;
goto out_put;
}
rcar_rst_base = base;
cfg = match->data;
saved_mode = ioread32(base + cfg->modemr);
pr_debug("%pOF: MODE = 0x%08x\n", np, saved_mode);
out_put:
of_node_put(np);
return error;
}
int __init rcar_rst_read_mode_pins(u32 *mode)
{
int error;
if (!rcar_rst_base) {
error = rcar_rst_init();
if (error)
return error;
}
*mode = saved_mode;
return 0;
}