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