1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved. 4 */ 5 6 #include <linux/kernel.h> 7 #include <linux/of.h> 8 #include <linux/of_address.h> 9 #include <linux/io.h> 10 11 #include <soc/tegra/fuse.h> 12 #include <soc/tegra/common.h> 13 14 #include "fuse.h" 15 16 #define FUSE_SKU_INFO 0x10 17 18 #define PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT 4 19 #define PMC_STRAPPING_OPT_A_RAM_CODE_MASK_LONG \ 20 (0xf << PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT) 21 #define PMC_STRAPPING_OPT_A_RAM_CODE_MASK_SHORT \ 22 (0x3 << PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT) 23 24 static void __iomem *apbmisc_base; 25 static void __iomem *strapping_base; 26 static bool long_ram_code; 27 28 u32 tegra_read_chipid(void) 29 { 30 if (!apbmisc_base) { 31 WARN(1, "Tegra Chip ID not yet available\n"); 32 return 0; 33 } 34 35 return readl_relaxed(apbmisc_base + 4); 36 } 37 38 u8 tegra_get_chip_id(void) 39 { 40 return (tegra_read_chipid() >> 8) & 0xff; 41 } 42 43 u32 tegra_read_straps(void) 44 { 45 if (strapping_base) 46 return readl_relaxed(strapping_base); 47 else 48 return 0; 49 } 50 51 u32 tegra_read_ram_code(void) 52 { 53 u32 straps = tegra_read_straps(); 54 55 if (long_ram_code) 56 straps &= PMC_STRAPPING_OPT_A_RAM_CODE_MASK_LONG; 57 else 58 straps &= PMC_STRAPPING_OPT_A_RAM_CODE_MASK_SHORT; 59 60 return straps >> PMC_STRAPPING_OPT_A_RAM_CODE_SHIFT; 61 } 62 63 static const struct of_device_id apbmisc_match[] __initconst = { 64 { .compatible = "nvidia,tegra20-apbmisc", }, 65 { .compatible = "nvidia,tegra186-misc", }, 66 {}, 67 }; 68 69 void __init tegra_init_revision(void) 70 { 71 u32 id, chip_id, minor_rev; 72 int rev; 73 74 id = tegra_read_chipid(); 75 chip_id = (id >> 8) & 0xff; 76 minor_rev = (id >> 16) & 0xf; 77 78 switch (minor_rev) { 79 case 1: 80 rev = TEGRA_REVISION_A01; 81 break; 82 case 2: 83 rev = TEGRA_REVISION_A02; 84 break; 85 case 3: 86 if (chip_id == TEGRA20 && (tegra_fuse_read_spare(18) || 87 tegra_fuse_read_spare(19))) 88 rev = TEGRA_REVISION_A03p; 89 else 90 rev = TEGRA_REVISION_A03; 91 break; 92 case 4: 93 rev = TEGRA_REVISION_A04; 94 break; 95 default: 96 rev = TEGRA_REVISION_UNKNOWN; 97 } 98 99 tegra_sku_info.revision = rev; 100 101 tegra_sku_info.sku_id = tegra_fuse_read_early(FUSE_SKU_INFO); 102 } 103 104 void __init tegra_init_apbmisc(void) 105 { 106 struct resource apbmisc, straps; 107 struct device_node *np; 108 109 np = of_find_matching_node(NULL, apbmisc_match); 110 if (!np) { 111 /* 112 * Fall back to legacy initialization for 32-bit ARM only. All 113 * 64-bit ARM device tree files for Tegra are required to have 114 * an APBMISC node. 115 * 116 * This is for backwards-compatibility with old device trees 117 * that didn't contain an APBMISC node. 118 */ 119 if (IS_ENABLED(CONFIG_ARM) && soc_is_tegra()) { 120 /* APBMISC registers (chip revision, ...) */ 121 apbmisc.start = 0x70000800; 122 apbmisc.end = 0x70000863; 123 apbmisc.flags = IORESOURCE_MEM; 124 125 /* strapping options */ 126 if (tegra_get_chip_id() == TEGRA124) { 127 straps.start = 0x7000e864; 128 straps.end = 0x7000e867; 129 } else { 130 straps.start = 0x70000008; 131 straps.end = 0x7000000b; 132 } 133 134 straps.flags = IORESOURCE_MEM; 135 136 pr_warn("Using APBMISC region %pR\n", &apbmisc); 137 pr_warn("Using strapping options registers %pR\n", 138 &straps); 139 } else { 140 /* 141 * At this point we're not running on Tegra, so play 142 * nice with multi-platform kernels. 143 */ 144 return; 145 } 146 } else { 147 /* 148 * Extract information from the device tree if we've found a 149 * matching node. 150 */ 151 if (of_address_to_resource(np, 0, &apbmisc) < 0) { 152 pr_err("failed to get APBMISC registers\n"); 153 return; 154 } 155 156 if (of_address_to_resource(np, 1, &straps) < 0) { 157 pr_err("failed to get strapping options registers\n"); 158 return; 159 } 160 } 161 162 apbmisc_base = ioremap_nocache(apbmisc.start, resource_size(&apbmisc)); 163 if (!apbmisc_base) 164 pr_err("failed to map APBMISC registers\n"); 165 166 strapping_base = ioremap_nocache(straps.start, resource_size(&straps)); 167 if (!strapping_base) 168 pr_err("failed to map strapping options registers\n"); 169 170 long_ram_code = of_property_read_bool(np, "nvidia,long-ram-code"); 171 } 172