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,r8a77970-rst", .data = &rcar_rst_gen2 }, 45 { .compatible = "renesas,r8a77995-rst", .data = &rcar_rst_gen2 }, 46 { /* sentinel */ } 47 }; 48 49 static void __iomem *rcar_rst_base __initdata; 50 static u32 saved_mode __initdata; 51 52 static int __init rcar_rst_init(void) 53 { 54 const struct of_device_id *match; 55 const struct rst_config *cfg; 56 struct device_node *np; 57 void __iomem *base; 58 int error = 0; 59 60 np = of_find_matching_node_and_match(NULL, rcar_rst_matches, &match); 61 if (!np) 62 return -ENODEV; 63 64 base = of_iomap(np, 0); 65 if (!base) { 66 pr_warn("%pOF: Cannot map regs\n", np); 67 error = -ENOMEM; 68 goto out_put; 69 } 70 71 rcar_rst_base = base; 72 cfg = match->data; 73 saved_mode = ioread32(base + cfg->modemr); 74 75 pr_debug("%pOF: MODE = 0x%08x\n", np, saved_mode); 76 77 out_put: 78 of_node_put(np); 79 return error; 80 } 81 82 int __init rcar_rst_read_mode_pins(u32 *mode) 83 { 84 int error; 85 86 if (!rcar_rst_base) { 87 error = rcar_rst_init(); 88 if (error) 89 return error; 90 } 91 92 *mode = saved_mode; 93 return 0; 94 } 95