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