1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/arch/arm/kernel/atags_compat.c 4 * 5 * Copyright (C) 2001 Russell King 6 * 7 * We keep the old params compatibility cruft in one place (here) 8 * so we don't end up with lots of mess around other places. 9 * 10 * NOTE: 11 * The old struct param_struct is deprecated, but it will be kept in 12 * the kernel for 5 years from now (2001). This will allow boot loaders 13 * to convert to the new struct tag way. 14 */ 15 #include <linux/types.h> 16 #include <linux/kernel.h> 17 #include <linux/string.h> 18 #include <linux/init.h> 19 20 #include <asm/setup.h> 21 #include <asm/mach-types.h> 22 #include <asm/page.h> 23 24 #include <asm/mach/arch.h> 25 26 #include "atags.h" 27 28 /* 29 * Usage: 30 * - do not go blindly adding fields, add them at the end 31 * - when adding fields, don't rely on the address until 32 * a patch from me has been released 33 * - unused fields should be zero (for future expansion) 34 * - this structure is relatively short-lived - only 35 * guaranteed to contain useful data in setup_arch() 36 * 37 * This is the old deprecated way to pass parameters to the kernel 38 */ 39 struct param_struct { 40 union { 41 struct { 42 unsigned long page_size; /* 0 */ 43 unsigned long nr_pages; /* 4 */ 44 unsigned long ramdisk_size; /* 8 */ 45 unsigned long flags; /* 12 */ 46 #define FLAG_READONLY 1 47 #define FLAG_RDLOAD 4 48 #define FLAG_RDPROMPT 8 49 unsigned long rootdev; /* 16 */ 50 unsigned long video_num_cols; /* 20 */ 51 unsigned long video_num_rows; /* 24 */ 52 unsigned long video_x; /* 28 */ 53 unsigned long video_y; /* 32 */ 54 unsigned long memc_control_reg; /* 36 */ 55 unsigned char sounddefault; /* 40 */ 56 unsigned char adfsdrives; /* 41 */ 57 unsigned char bytes_per_char_h; /* 42 */ 58 unsigned char bytes_per_char_v; /* 43 */ 59 unsigned long pages_in_bank[4]; /* 44 */ 60 unsigned long pages_in_vram; /* 60 */ 61 unsigned long initrd_start; /* 64 */ 62 unsigned long initrd_size; /* 68 */ 63 unsigned long rd_start; /* 72 */ 64 unsigned long system_rev; /* 76 */ 65 unsigned long system_serial_low; /* 80 */ 66 unsigned long system_serial_high; /* 84 */ 67 unsigned long mem_fclk_21285; /* 88 */ 68 } s; 69 char unused[256]; 70 } u1; 71 union { 72 char paths[8][128]; 73 struct { 74 unsigned long magic; 75 char n[1024 - sizeof(unsigned long)]; 76 } s; 77 } u2; 78 char commandline[COMMAND_LINE_SIZE]; 79 }; 80 81 static struct tag * __init memtag(struct tag *tag, unsigned long start, unsigned long size) 82 { 83 tag = tag_next(tag); 84 tag->hdr.tag = ATAG_MEM; 85 tag->hdr.size = tag_size(tag_mem32); 86 tag->u.mem.size = size; 87 tag->u.mem.start = start; 88 89 return tag; 90 } 91 92 static void __init build_tag_list(struct param_struct *params, void *taglist) 93 { 94 struct tag *tag = taglist; 95 96 if (params->u1.s.page_size != PAGE_SIZE) { 97 pr_warn("Warning: bad configuration page, trying to continue\n"); 98 return; 99 } 100 101 printk(KERN_DEBUG "Converting old-style param struct to taglist\n"); 102 103 #ifdef CONFIG_ARCH_NETWINDER 104 if (params->u1.s.nr_pages != 0x02000 && 105 params->u1.s.nr_pages != 0x04000 && 106 params->u1.s.nr_pages != 0x08000 && 107 params->u1.s.nr_pages != 0x10000) { 108 pr_warn("Warning: bad NeTTrom parameters detected, using defaults\n"); 109 110 params->u1.s.nr_pages = 0x1000; /* 16MB */ 111 params->u1.s.ramdisk_size = 0; 112 params->u1.s.flags = FLAG_READONLY; 113 params->u1.s.initrd_start = 0; 114 params->u1.s.initrd_size = 0; 115 params->u1.s.rd_start = 0; 116 } 117 #endif 118 119 tag->hdr.tag = ATAG_CORE; 120 tag->hdr.size = tag_size(tag_core); 121 tag->u.core.flags = params->u1.s.flags & FLAG_READONLY; 122 tag->u.core.pagesize = params->u1.s.page_size; 123 tag->u.core.rootdev = params->u1.s.rootdev; 124 125 tag = tag_next(tag); 126 tag->hdr.tag = ATAG_RAMDISK; 127 tag->hdr.size = tag_size(tag_ramdisk); 128 tag->u.ramdisk.flags = (params->u1.s.flags & FLAG_RDLOAD ? 1 : 0) | 129 (params->u1.s.flags & FLAG_RDPROMPT ? 2 : 0); 130 tag->u.ramdisk.size = params->u1.s.ramdisk_size; 131 tag->u.ramdisk.start = params->u1.s.rd_start; 132 133 tag = tag_next(tag); 134 tag->hdr.tag = ATAG_INITRD; 135 tag->hdr.size = tag_size(tag_initrd); 136 tag->u.initrd.start = params->u1.s.initrd_start; 137 tag->u.initrd.size = params->u1.s.initrd_size; 138 139 tag = tag_next(tag); 140 tag->hdr.tag = ATAG_SERIAL; 141 tag->hdr.size = tag_size(tag_serialnr); 142 tag->u.serialnr.low = params->u1.s.system_serial_low; 143 tag->u.serialnr.high = params->u1.s.system_serial_high; 144 145 tag = tag_next(tag); 146 tag->hdr.tag = ATAG_REVISION; 147 tag->hdr.size = tag_size(tag_revision); 148 tag->u.revision.rev = params->u1.s.system_rev; 149 150 #ifdef CONFIG_ARCH_ACORN 151 if (machine_is_riscpc()) { 152 int i; 153 for (i = 0; i < 4; i++) 154 tag = memtag(tag, PHYS_OFFSET + (i << 26), 155 params->u1.s.pages_in_bank[i] * PAGE_SIZE); 156 } else 157 #endif 158 tag = memtag(tag, PHYS_OFFSET, params->u1.s.nr_pages * PAGE_SIZE); 159 160 #ifdef CONFIG_FOOTBRIDGE 161 if (params->u1.s.mem_fclk_21285) { 162 tag = tag_next(tag); 163 tag->hdr.tag = ATAG_MEMCLK; 164 tag->hdr.size = tag_size(tag_memclk); 165 tag->u.memclk.fmemclk = params->u1.s.mem_fclk_21285; 166 } 167 #endif 168 169 #ifdef CONFIG_ARCH_EBSA285 170 if (machine_is_ebsa285()) { 171 tag = tag_next(tag); 172 tag->hdr.tag = ATAG_VIDEOTEXT; 173 tag->hdr.size = tag_size(tag_videotext); 174 tag->u.videotext.x = params->u1.s.video_x; 175 tag->u.videotext.y = params->u1.s.video_y; 176 tag->u.videotext.video_page = 0; 177 tag->u.videotext.video_mode = 0; 178 tag->u.videotext.video_cols = params->u1.s.video_num_cols; 179 tag->u.videotext.video_ega_bx = 0; 180 tag->u.videotext.video_lines = params->u1.s.video_num_rows; 181 tag->u.videotext.video_isvga = 1; 182 tag->u.videotext.video_points = 8; 183 } 184 #endif 185 186 #ifdef CONFIG_ARCH_ACORN 187 tag = tag_next(tag); 188 tag->hdr.tag = ATAG_ACORN; 189 tag->hdr.size = tag_size(tag_acorn); 190 tag->u.acorn.memc_control_reg = params->u1.s.memc_control_reg; 191 tag->u.acorn.vram_pages = params->u1.s.pages_in_vram; 192 tag->u.acorn.sounddefault = params->u1.s.sounddefault; 193 tag->u.acorn.adfsdrives = params->u1.s.adfsdrives; 194 #endif 195 196 tag = tag_next(tag); 197 tag->hdr.tag = ATAG_CMDLINE; 198 tag->hdr.size = (strlen(params->commandline) + 3 + 199 sizeof(struct tag_header)) >> 2; 200 strcpy(tag->u.cmdline.cmdline, params->commandline); 201 202 tag = tag_next(tag); 203 tag->hdr.tag = ATAG_NONE; 204 tag->hdr.size = 0; 205 206 memmove(params, taglist, ((int)tag) - ((int)taglist) + 207 sizeof(struct tag_header)); 208 } 209 210 void __init convert_to_tag_list(struct tag *tags) 211 { 212 struct param_struct *params = (struct param_struct *)tags; 213 build_tag_list(params, ¶ms->u2); 214 } 215