diff options
Diffstat (limited to 'drivers/soc/renesas/rcar-rst.c')
-rw-r--r-- | drivers/soc/renesas/rcar-rst.c | 171 |
1 files changed, 171 insertions, 0 deletions
diff --git a/drivers/soc/renesas/rcar-rst.c b/drivers/soc/renesas/rcar-rst.c new file mode 100644 index 000000000..e1c7e91f5 --- /dev/null +++ b/drivers/soc/renesas/rcar-rst.c @@ -0,0 +1,171 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * R-Car Gen1 RESET/WDT, R-Car Gen2, Gen3, and RZ/G RST Driver + * + * Copyright (C) 2016 Glider bvba + */ + +#include <linux/err.h> +#include <linux/io.h> +#include <linux/of_address.h> +#include <linux/soc/renesas/rcar-rst.h> + +#define WDTRSTCR_RESET 0xA55A0002 +#define WDTRSTCR 0x0054 + +#define CR7BAR 0x0070 +#define CR7BAREN BIT(4) +#define CR7BAR_MASK 0xFFFC0000 + +static void __iomem *rcar_rst_base; +static u32 saved_mode __initdata; +static int (*rcar_rst_set_rproc_boot_addr_func)(u64 boot_addr); + +static int rcar_rst_enable_wdt_reset(void __iomem *base) +{ + iowrite32(WDTRSTCR_RESET, base + WDTRSTCR); + return 0; +} + +/* + * Most of the R-Car Gen3 SoCs have an ARM Realtime Core. + * Firmware boot address has to be set in CR7BAR before + * starting the realtime core. + * Boot address must be aligned on a 256k boundary. + */ +static int rcar_rst_set_gen3_rproc_boot_addr(u64 boot_addr) +{ + if (boot_addr & ~(u64)CR7BAR_MASK) { + pr_err("Invalid boot address got %llx\n", boot_addr); + return -EINVAL; + } + + iowrite32(boot_addr, rcar_rst_base + CR7BAR); + iowrite32(boot_addr | CR7BAREN, rcar_rst_base + CR7BAR); + + return 0; +} + +struct rst_config { + unsigned int modemr; /* Mode Monitoring Register Offset */ + int (*configure)(void __iomem *base); /* Platform specific config */ + int (*set_rproc_boot_addr)(u64 boot_addr); +}; + +static const struct rst_config rcar_rst_gen1 __initconst = { + .modemr = 0x20, +}; + +static const struct rst_config rcar_rst_gen2 __initconst = { + .modemr = 0x60, + .configure = rcar_rst_enable_wdt_reset, +}; + +static const struct rst_config rcar_rst_gen3 __initconst = { + .modemr = 0x60, + .set_rproc_boot_addr = rcar_rst_set_gen3_rproc_boot_addr, +}; + +static const struct rst_config rcar_rst_gen4 __initconst = { + .modemr = 0x00, /* MODEMR0 and it has CPG related bits */ +}; + +static const struct of_device_id rcar_rst_matches[] __initconst = { + /* RZ/G1 is handled like R-Car Gen2 */ + { .compatible = "renesas,r8a7742-rst", .data = &rcar_rst_gen2 }, + { .compatible = "renesas,r8a7743-rst", .data = &rcar_rst_gen2 }, + { .compatible = "renesas,r8a7744-rst", .data = &rcar_rst_gen2 }, + { .compatible = "renesas,r8a7745-rst", .data = &rcar_rst_gen2 }, + { .compatible = "renesas,r8a77470-rst", .data = &rcar_rst_gen2 }, + /* RZ/G2 is handled like R-Car Gen3 */ + { .compatible = "renesas,r8a774a1-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a774b1-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a774c0-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a774e1-rst", .data = &rcar_rst_gen3 }, + /* 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 */ + { .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a77961-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a77965-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a77970-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a77980-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a77990-rst", .data = &rcar_rst_gen3 }, + { .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen3 }, + /* R-Car Gen4 */ + { .compatible = "renesas,r8a779a0-rst", .data = &rcar_rst_gen4 }, + { .compatible = "renesas,r8a779f0-rst", .data = &rcar_rst_gen4 }, + { .compatible = "renesas,r8a779g0-rst", .data = &rcar_rst_gen4 }, + { /* sentinel */ } +}; + +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; + rcar_rst_set_rproc_boot_addr_func = cfg->set_rproc_boot_addr; + + saved_mode = ioread32(base + cfg->modemr); + if (cfg->configure) { + error = cfg->configure(base); + if (error) { + pr_warn("%pOF: Cannot run SoC specific configuration\n", + np); + goto out_put; + } + } + + 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; +} + +int rcar_rst_set_rproc_boot_addr(u64 boot_addr) +{ + if (!rcar_rst_set_rproc_boot_addr_func) + return -EIO; + + return rcar_rst_set_rproc_boot_addr_func(boot_addr); +} +EXPORT_SYMBOL_GPL(rcar_rst_set_rproc_boot_addr); |