| rjw | 1f88458 | 2022-01-06 17:20:42 +0800 | [diff] [blame^] | 1 | /* |
| 2 | * R-Car Gen1 RESET/WDT, R-Car Gen2, Gen3, and RZ/G RST Driver |
| 3 | * |
| 4 | * Copyright (C) 2016 Glider bvba |
| 5 | * |
| 6 | * This file is subject to the terms and conditions of the GNU General Public |
| 7 | * License. See the file "COPYING" in the main directory of this archive |
| 8 | * for more details. |
| 9 | */ |
| 10 | |
| 11 | #include <linux/err.h> |
| 12 | #include <linux/io.h> |
| 13 | #include <linux/of_address.h> |
| 14 | #include <linux/soc/renesas/rcar-rst.h> |
| 15 | |
| 16 | struct rst_config { |
| 17 | unsigned int modemr; /* Mode Monitoring Register Offset */ |
| 18 | }; |
| 19 | |
| 20 | static const struct rst_config rcar_rst_gen1 __initconst = { |
| 21 | .modemr = 0x20, |
| 22 | }; |
| 23 | |
| 24 | static const struct rst_config rcar_rst_gen2 __initconst = { |
| 25 | .modemr = 0x60, |
| 26 | }; |
| 27 | |
| 28 | static const struct of_device_id rcar_rst_matches[] __initconst = { |
| 29 | /* RZ/G is handled like R-Car Gen2 */ |
| 30 | { .compatible = "renesas,r8a7743-rst", .data = &rcar_rst_gen2 }, |
| 31 | { .compatible = "renesas,r8a7745-rst", .data = &rcar_rst_gen2 }, |
| 32 | /* R-Car Gen1 */ |
| 33 | { .compatible = "renesas,r8a7778-reset-wdt", .data = &rcar_rst_gen1 }, |
| 34 | { .compatible = "renesas,r8a7779-reset-wdt", .data = &rcar_rst_gen1 }, |
| 35 | /* R-Car Gen2 */ |
| 36 | { .compatible = "renesas,r8a7790-rst", .data = &rcar_rst_gen2 }, |
| 37 | { .compatible = "renesas,r8a7791-rst", .data = &rcar_rst_gen2 }, |
| 38 | { .compatible = "renesas,r8a7792-rst", .data = &rcar_rst_gen2 }, |
| 39 | { .compatible = "renesas,r8a7793-rst", .data = &rcar_rst_gen2 }, |
| 40 | { .compatible = "renesas,r8a7794-rst", .data = &rcar_rst_gen2 }, |
| 41 | /* R-Car Gen3 is handled like R-Car Gen2 */ |
| 42 | { .compatible = "renesas,r8a7795-rst", .data = &rcar_rst_gen2 }, |
| 43 | { .compatible = "renesas,r8a7796-rst", .data = &rcar_rst_gen2 }, |
| 44 | { .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen2 }, |
| 45 | { /* sentinel */ } |
| 46 | }; |
| 47 | |
| 48 | static void __iomem *rcar_rst_base __initdata; |
| 49 | static u32 saved_mode __initdata; |
| 50 | |
| 51 | static int __init rcar_rst_init(void) |
| 52 | { |
| 53 | const struct of_device_id *match; |
| 54 | const struct rst_config *cfg; |
| 55 | struct device_node *np; |
| 56 | void __iomem *base; |
| 57 | int error = 0; |
| 58 | |
| 59 | np = of_find_matching_node_and_match(NULL, rcar_rst_matches, &match); |
| 60 | if (!np) |
| 61 | return -ENODEV; |
| 62 | |
| 63 | base = of_iomap(np, 0); |
| 64 | if (!base) { |
| 65 | pr_warn("%pOF: Cannot map regs\n", np); |
| 66 | error = -ENOMEM; |
| 67 | goto out_put; |
| 68 | } |
| 69 | |
| 70 | rcar_rst_base = base; |
| 71 | cfg = match->data; |
| 72 | saved_mode = ioread32(base + cfg->modemr); |
| 73 | |
| 74 | pr_debug("%pOF: MODE = 0x%08x\n", np, saved_mode); |
| 75 | |
| 76 | out_put: |
| 77 | of_node_put(np); |
| 78 | return error; |
| 79 | } |
| 80 | |
| 81 | int __init rcar_rst_read_mode_pins(u32 *mode) |
| 82 | { |
| 83 | int error; |
| 84 | |
| 85 | if (!rcar_rst_base) { |
| 86 | error = rcar_rst_init(); |
| 87 | if (error) |
| 88 | return error; |
| 89 | } |
| 90 | |
| 91 | *mode = saved_mode; |
| 92 | return 0; |
| 93 | } |