arch/arm/kernel/compat.c

   1 /*
   2  *  linux/arch/arm/kernel/compat.c
   3  *
   4  *  Copyright (C) 2001 Russell King
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 as
   8  * published by the Free Software Foundation.
   9  *
  10  * We keep the old params compatibility cruft in one place (here)
  11  * so we don't end up with lots of mess around other places.
  12  *
  13  * NOTE:
  14  *  The old struct param_struct is deprecated, but it will be kept in
  15  *  the kernel for 5 years from now (2001). This will allow boot loaders
  16  *  to convert to the new struct tag way.
  17  */
  18 #include <linux/config.h>
  19 #include <linux/types.h>
  20 #include <linux/kernel.h>
  21 #include <linux/string.h>
  22 #include <linux/init.h>
  23
  24 #include <asm/setup.h>
  25 #include <asm/mach-types.h>
  26 #include <asm/page.h>
  27
  28 #include <asm/mach/arch.h>
  29
  30 #include "compat.h"
  31
  32 /*
  33  * Usage:
  34  *  - do not go blindly adding fields, add them at the end
  35  *  - when adding fields, don't rely on the address until
  36  *    a patch from me has been released
  37  *  - unused fields should be zero (for future expansion)
  38  *  - this structure is relatively short-lived - only
  39  *    guaranteed to contain useful data in setup_arch()
  40  *
  41  * This is the old deprecated way to pass parameters to the kernel
  42  */
  43 struct param_struct {
  44     union {
  45         struct {
  46             unsigned long page_size;            /*  0 */
  47             unsigned long nr_pages;             /*  4 */
  48             unsigned long ramdisk_size;         /*  8 */
  49             unsigned long flags;                /* 12 */
  50 #define FLAG_READONLY   1
  51 #define FLAG_RDLOAD     4
  52 #define FLAG_RDPROMPT   8
  53             unsigned long rootdev;              /* 16 */
  54             unsigned long video_num_cols;       /* 20 */
  55             unsigned long video_num_rows;       /* 24 */
  56             unsigned long video_x;              /* 28 */
  57             unsigned long video_y;              /* 32 */
  58             unsigned long memc_control_reg;     /* 36 */
  59             unsigned char sounddefault;         /* 40 */
  60             unsigned char adfsdrives;           /* 41 */
  61             unsigned char bytes_per_char_h;     /* 42 */
  62             unsigned char bytes_per_char_v;     /* 43 */
  63             unsigned long pages_in_bank[4];     /* 44 */
  64             unsigned long pages_in_vram;        /* 60 */
  65             unsigned long initrd_start;         /* 64 */
  66             unsigned long initrd_size;          /* 68 */
  67             unsigned long rd_start;             /* 72 */
  68             unsigned long system_rev;           /* 76 */
  69             unsigned long system_serial_low;    /* 80 */
  70             unsigned long system_serial_high;   /* 84 */
  71             unsigned long mem_fclk_21285;       /* 88 */
  72         } s;
  73         char unused[256];
  74     } u1;
  75     union {
  76         char paths[8][128];
  77         struct {
  78             unsigned long magic;
  79             char n[1024 - sizeof(unsigned long)];
  80         } s;
  81     } u2;
  82     char commandline[COMMAND_LINE_SIZE];
  83 };
  84
  85 static struct tag * __init memtag(struct tag *tag, unsigned long start, unsigned long size)
  86 {
  87         tag = tag_next(tag);
  88         tag->hdr.tag = ATAG_MEM;
  89         tag->hdr.size = tag_size(tag_mem32);
  90         tag->u.mem.size = size;
  91         tag->u.mem.start = start;
  92
  93         return tag;
  94 }
  95
  96 static void __init build_tag_list(struct param_struct *params, void *taglist)
  97 {
  98         struct tag *tag = taglist;
  99
 100         if (params->u1.s.page_size != PAGE_SIZE) {
 101                 printk(KERN_WARNING "Warning: bad configuration page, "
 102                        "trying to continue\n");
 103                 return;
 104         }
 105
 106         printk(KERN_DEBUG "Converting old-style param struct to taglist\n");
 107
 108 #ifdef CONFIG_ARCH_NETWINDER
 109         if (params->u1.s.nr_pages != 0x02000 &&
 110             params->u1.s.nr_pages != 0x04000 &&
 111             params->u1.s.nr_pages != 0x08000 &&
 112             params->u1.s.nr_pages != 0x10000) {
 113                 printk(KERN_WARNING "Warning: bad NeTTrom parameters "
 114                        "detected, using defaults\n");
 115
 116                 params->u1.s.nr_pages = 0x1000; /* 16MB */
 117                 params->u1.s.ramdisk_size = 0;
 118                 params->u1.s.flags = FLAG_READONLY;
 119                 params->u1.s.initrd_start = 0;
 120                 params->u1.s.initrd_size = 0;
 121                 params->u1.s.rd_start = 0;
 122         }
 123 #endif
 124
 125         tag->hdr.tag  = ATAG_CORE;
 126         tag->hdr.size = tag_size(tag_core);
 127         tag->u.core.flags = params->u1.s.flags & FLAG_READONLY;
 128         tag->u.core.pagesize = params->u1.s.page_size;
 129         tag->u.core.rootdev = params->u1.s.rootdev;
 130
 131         tag = tag_next(tag);
 132         tag->hdr.tag = ATAG_RAMDISK;
 133         tag->hdr.size = tag_size(tag_ramdisk);
 134         tag->u.ramdisk.flags = (params->u1.s.flags & FLAG_RDLOAD ? 1 : 0) |
 135                                (params->u1.s.flags & FLAG_RDPROMPT ? 2 : 0);
 136         tag->u.ramdisk.size  = params->u1.s.ramdisk_size;
 137         tag->u.ramdisk.start = params->u1.s.rd_start;
 138
 139         tag = tag_next(tag);
 140         tag->hdr.tag = ATAG_INITRD;
 141         tag->hdr.size = tag_size(tag_initrd);
 142         tag->u.initrd.start = params->u1.s.initrd_start;
 143         tag->u.initrd.size  = params->u1.s.initrd_size;
 144
 145         tag = tag_next(tag);
 146         tag->hdr.tag = ATAG_SERIAL;
 147         tag->hdr.size = tag_size(tag_serialnr);
 148         tag->u.serialnr.low = params->u1.s.system_serial_low;
 149         tag->u.serialnr.high = params->u1.s.system_serial_high;
 150
 151         tag = tag_next(tag);
 152         tag->hdr.tag = ATAG_REVISION;
 153         tag->hdr.size = tag_size(tag_revision);
 154         tag->u.revision.rev = params->u1.s.system_rev;
 155
 156 #ifdef CONFIG_ARCH_ACORN
 157         if (machine_is_riscpc()) {
 158                 int i;
 159                 for (i = 0; i < 4; i++)
 160                         tag = memtag(tag, PHYS_OFFSET + (i << 26),
 161                                  params->u1.s.pages_in_bank[i] * PAGE_SIZE);
 162         } else
 163 #endif
 164         tag = memtag(tag, PHYS_OFFSET, params->u1.s.nr_pages * PAGE_SIZE);
 165
 166 #ifdef CONFIG_FOOTBRIDGE
 167         if (params->u1.s.mem_fclk_21285) {
 168                 tag = tag_next(tag);
 169                 tag->hdr.tag = ATAG_MEMCLK;
 170                 tag->hdr.size = tag_size(tag_memclk);
 171                 tag->u.memclk.fmemclk = params->u1.s.mem_fclk_21285;
 172         }
 173 #endif
 174
 175 #ifdef CONFIG_ARCH_EBSA285
 176         if (machine_is_ebsa285()) {
 177                 tag = tag_next(tag);
 178                 tag->hdr.tag = ATAG_VIDEOTEXT;
 179                 tag->hdr.size = tag_size(tag_videotext);
 180                 tag->u.videotext.x            = params->u1.s.video_x;
 181                 tag->u.videotext.y            = params->u1.s.video_y;
 182                 tag->u.videotext.video_page   = 0;
 183                 tag->u.videotext.video_mode   = 0;
 184                 tag->u.videotext.video_cols   = params->u1.s.video_num_cols;
 185                 tag->u.videotext.video_ega_bx = 0;
 186                 tag->u.videotext.video_lines  = params->u1.s.video_num_rows;
 187                 tag->u.videotext.video_isvga  = 1;
 188                 tag->u.videotext.video_points = 8;
 189         }
 190 #endif
 191
 192 #ifdef CONFIG_ARCH_ACORN
 193         tag = tag_next(tag);
 194         tag->hdr.tag = ATAG_ACORN;
 195         tag->hdr.size = tag_size(tag_acorn);
 196         tag->u.acorn.memc_control_reg = params->u1.s.memc_control_reg;
 197         tag->u.acorn.vram_pages       = params->u1.s.pages_in_vram;
 198         tag->u.acorn.sounddefault     = params->u1.s.sounddefault;
 199         tag->u.acorn.adfsdrives       = params->u1.s.adfsdrives;
 200 #endif
 201
 202         tag = tag_next(tag);
 203         tag->hdr.tag = ATAG_CMDLINE;
 204         tag->hdr.size = (strlen(params->commandline) + 3 +
 205                          sizeof(struct tag_header)) >> 2;
 206         strcpy(tag->u.cmdline.cmdline, params->commandline);
 207
 208         tag = tag_next(tag);
 209         tag->hdr.tag = ATAG_NONE;
 210         tag->hdr.size = 0;
 211
 212         memmove(params, taglist, ((int)tag) - ((int)taglist) +
 213                                  sizeof(struct tag_header));
 214 }
 215
 216 void __init convert_to_tag_list(struct tag *tags)
 217 {
 218         struct param_struct *params = (struct param_struct *)tags;
 219         build_tag_list(params, &params->u2);
 220 }
 221
 222 void __init squash_mem_tags(struct tag *tag)
 223 {
 224         for (; tag->hdr.size; tag = tag_next(tag))
 225                 if (tag->hdr.tag == ATAG_MEM)
 226                         tag->hdr.tag = ATAG_NONE;
 227 }