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/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/arch.h>
  29 //#include <asm/mach/irq.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  */
  42 struct 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
  84 static 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
  95 static 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         tag->hdr.tag  = ATAG_CORE;
 108         tag->hdr.size = tag_size(tag_core);
 109         tag->u.core.flags = params->u1.s.flags & FLAG_READONLY;
 110         tag->u.core.pagesize = params->u1.s.page_size;
 111         tag->u.core.rootdev = params->u1.s.rootdev;
 112
 113         tag = tag_next(tag);
 114         tag->hdr.tag = ATAG_RAMDISK;
 115         tag->hdr.size = tag_size(tag_ramdisk);
 116         tag->u.ramdisk.flags = (params->u1.s.flags & FLAG_RDLOAD ? 1 : 0) |
 117                                (params->u1.s.flags & FLAG_RDPROMPT ? 2 : 0);
 118         tag->u.ramdisk.size  = params->u1.s.ramdisk_size;
 119         tag->u.ramdisk.start = params->u1.s.rd_start;
 120
 121         tag = tag_next(tag);
 122         tag->hdr.tag = ATAG_INITRD;
 123         tag->hdr.size = tag_size(tag_initrd);
 124         tag->u.initrd.start = params->u1.s.initrd_start;
 125         tag->u.initrd.size  = params->u1.s.initrd_size;
 126
 127         tag = tag_next(tag);
 128         tag->hdr.tag = ATAG_SERIAL;
 129         tag->hdr.size = tag_size(tag_serialnr);
 130         tag->u.serialnr.low = params->u1.s.system_serial_low;
 131         tag->u.serialnr.high = params->u1.s.system_serial_high;
 132
 133         tag = tag_next(tag);
 134         tag->hdr.tag = ATAG_REVISION;
 135         tag->hdr.size = tag_size(tag_revision);
 136         tag->u.revision.rev = params->u1.s.system_rev;
 137
 138         tag = memtag(tag, PHYS_OFFSET, params->u1.s.nr_pages * PAGE_SIZE);
 139
 140         tag = tag_next(tag);
 141         tag->hdr.tag = ATAG_ACORN;
 142         tag->hdr.size = tag_size(tag_acorn);
 143         tag->u.acorn.memc_control_reg = params->u1.s.memc_control_reg;
 144         tag->u.acorn.vram_pages       = params->u1.s.pages_in_vram;
 145         tag->u.acorn.sounddefault     = params->u1.s.sounddefault;
 146         tag->u.acorn.adfsdrives       = params->u1.s.adfsdrives;
 147
 148         tag = tag_next(tag);
 149         tag->hdr.tag = ATAG_CMDLINE;
 150         tag->hdr.size = (strlen(params->commandline) + 3 +
 151                          sizeof(struct tag_header)) >> 2;
 152         strcpy(tag->u.cmdline.cmdline, params->commandline);
 153
 154         tag = tag_next(tag);
 155         tag->hdr.tag = ATAG_NONE;
 156         tag->hdr.size = 0;
 157
 158         memmove(params, taglist, ((int)tag) - ((int)taglist) +
 159                                  sizeof(struct tag_header));
 160 }
 161
 162 void __init convert_to_tag_list(struct tag *tags)
 163 {
 164         struct param_struct *params = (struct param_struct *)tags;
 165         build_tag_list(params, &params->u2);
 166 }
 167
 168 void __init squash_mem_tags(struct tag *tag)
 169 {
 170         for (; tag->hdr.size; tag = tag_next(tag))
 171                 if (tag->hdr.tag == ATAG_MEM)
 172                         tag->hdr.tag = ATAG_NONE;
 173 }