diff options
Diffstat (limited to 'drivers/soc/renesas/rcar-rst.c')
-rw-r--r-- | drivers/soc/renesas/rcar-rst.c | 92 |
1 files changed, 92 insertions, 0 deletions
diff --git a/drivers/soc/renesas/rcar-rst.c b/drivers/soc/renesas/rcar-rst.c new file mode 100644 index 000000000000..a6d1c26d3167 --- /dev/null +++ b/drivers/soc/renesas/rcar-rst.c @@ -0,0 +1,92 @@ +/* + * 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 }, + { /* 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("%s: Cannot map regs\n", np->full_name); + error = -ENOMEM; + goto out_put; + } + + rcar_rst_base = base; + cfg = match->data; + saved_mode = ioread32(base + cfg->modemr); + + pr_debug("%s: MODE = 0x%08x\n", np->full_name, 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; +} |