arch/arm26/kernel/compat.c

   1 /*
   2  *  linux/arch/arm26/kernel/compat.c
   3  *
   4  *  Copyright (C) 2001 Russell King
   5  *                2003 Ian Molton
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  *
  11  * We keep the old params compatibility cruft in one place (here)
  12  * so we don't end up with lots of mess around other places.
  13  *
  14  * NOTE:
  15  *  The old struct param_struct is deprecated, but it will be kept in
  16  *  the kernel for 5 years from now (2001). This will allow boot loaders
  17  *  to convert to the new struct tag way.
  18  */
  19 #include <linux/config.h>
  20 #include <linux/types.h>
  21 #include <linux/kernel.h>
  22 #include <linux/string.h>
  23 #include <linux/init.h>
  24
  25 #include <asm/setup.h>
  26 #include <asm/mach-types.h>
  27 #include <asm/page.h>
  28
  29 //#include <asm/arch.h>
  30 //#include <asm/mach/irq.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         tag->hdr.tag  = ATAG_CORE;
 109         tag->hdr.size = tag_size(tag_core);
 110         tag->u.core.flags = params->u1.s.flags & FLAG_READONLY;
 111         tag->u.core.pagesize = params->u1.s.page_size;
 112         tag->u.core.rootdev = params->u1.s.rootdev;
 113
 114         tag = tag_next(tag);
 115         tag->hdr.tag = ATAG_RAMDISK;
 116         tag->hdr.size = tag_size(tag_ramdisk);
 117         tag->u.ramdisk.flags = (params->u1.s.flags & FLAG_RDLOAD ? 1 : 0) |
 118                                (params->u1.s.flags & FLAG_RDPROMPT ? 2 : 0);
 119         tag->u.ramdisk.size  = params->u1.s.ramdisk_size;
 120         tag->u.ramdisk.start = params->u1.s.rd_start;
 121
 122         tag = tag_next(tag);
 123         tag->hdr.tag = ATAG_INITRD;
 124         tag->hdr.size = tag_size(tag_initrd);
 125         tag->u.initrd.start = params->u1.s.initrd_start;
 126         tag->u.initrd.size  = params->u1.s.initrd_size;
 127
 128         tag = tag_next(tag);
 129         tag->hdr.tag = ATAG_SERIAL;
 130         tag->hdr.size = tag_size(tag_serialnr);
 131         tag->u.serialnr.low = params->u1.s.system_serial_low;
 132         tag->u.serialnr.high = params->u1.s.system_serial_high;
 133
 134         tag = tag_next(tag);
 135         tag->hdr.tag = ATAG_REVISION;
 136         tag->hdr.size = tag_size(tag_revision);
 137         tag->u.revision.rev = params->u1.s.system_rev;
 138
 139         tag = memtag(tag, PHYS_OFFSET, params->u1.s.nr_pages * PAGE_SIZE);
 140
 141         tag = tag_next(tag);
 142         tag->hdr.tag = ATAG_ACORN;
 143         tag->hdr.size = tag_size(tag_acorn);
 144         tag->u.acorn.memc_control_reg = params->u1.s.memc_control_reg;
 145         tag->u.acorn.vram_pages       = params->u1.s.pages_in_vram;
 146         tag->u.acorn.sounddefault     = params->u1.s.sounddefault;
 147         tag->u.acorn.adfsdrives       = params->u1.s.adfsdrives;
 148
 149         tag = tag_next(tag);
 150         tag->hdr.tag = ATAG_CMDLINE;
 151         tag->hdr.size = (strlen(params->commandline) + 3 +
 152                          sizeof(struct tag_header)) >> 2;
 153         strcpy(tag->u.cmdline.cmdline, params->commandline);
 154
 155         tag = tag_next(tag);
 156         tag->hdr.tag = ATAG_NONE;
 157         tag->hdr.size = 0;
 158
 159         memmove(params, taglist, ((int)tag) - ((int)taglist) +
 160                                  sizeof(struct tag_header));
 161 }
 162
 163 void __init convert_to_tag_list(struct tag *tags)
 164 {
 165         struct param_struct *params = (struct param_struct *)tags;
 166         build_tag_list(params, &params->u2);
 167 }
 168
 169 void __init squash_mem_tags(struct tag *tag)
 170 {
 171         for (; tag->hdr.size; tag = tag_next(tag))
 172                 if (tag->hdr.tag == ATAG_MEM)
 173                         tag->hdr.tag = ATAG_NONE;
 174 }