src/arch/arm/linux/atag.hh

   1 /*
   2  * Copyright (c) 2010 ARM Limited
   3  * All rights reserved
   4  *
   5  * The license below extends only to copyright in the software and shall
   6  * not be construed as granting a license to any other intellectual
   7  * property including but not limited to intellectual property relating
   8  * to a hardware implementation of the functionality of the software
   9  * licensed hereunder.  You may use the software subject to the license
  10  * terms below provided that you ensure that this notice is replicated
  11  * unmodified and in its entirety in all distributions of the software,
  12  * modified or unmodified, in source code or in binary form.
  13  *
  14  * Redistribution and use in source and binary forms, with or without
  15  * modification, are permitted provided that the following conditions are
  16  * met: redistributions of source code must retain the above copyright
  17  * notice, this list of conditions and the following disclaimer;
  18  * redistributions in binary form must reproduce the above copyright
  19  * notice, this list of conditions and the following disclaimer in the
  20  * documentation and/or other materials provided with the distribution;
  21  * neither the name of the copyright holders nor the names of its
  22  * contributors may be used to endorse or promote products derived from
  23  * this software without specific prior written permission.
  24  *
  25  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  26  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  27  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  28  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  29  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  30  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  31  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  32  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  33  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  34  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  35  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  36  *
  37  * Authors: Ali Saidi
  38  */
  39
  40 #ifndef __ARCH_ARM_LINUX_ATAG_HH__
  41 #define __ARCH_ARM_LINUX_ATAG_HH__
  42
  43 #include <cstring>
  44 #include <string>
  45 #include "base/types.hh"
  46
  47 enum {
  48     CoreTag   = 0x54410001,
  49     MemTag    = 0x54410002,
  50     RevTag    = 0x54410007,
  51     SerialTag = 0x54410006,
  52     CmdTag    = 0x54410009,
  53     NoneTag   = 0x00000000,
  54 };
  55
  56 class AtagHeader
  57 {
  58   protected:
  59     uint32_t *storage;
  60     uint32_t _size;
  61
  62   public:
  63     /** Tag (normally starts with 'T''A' and 16 bits of number */
  64     virtual uint32_t tag() = 0;
  65     /** If the header should be 0 size */
  66     virtual bool null() { return false; }
  67
  68     uint32_t size() const { return _size; }
  69
  70     AtagHeader(uint32_t s)
  71         : _size(s)
  72     {
  73         storage = new uint32_t[size()];
  74     }
  75
  76     virtual ~AtagHeader()
  77     {
  78         delete[] storage;
  79     }
  80
  81     uint32_t copyOut(uint8_t *p)
  82     {
  83         storage[0] = null() ? 0 : size();
  84         storage[1] = tag();
  85         memcpy(p, storage, size() << 2);
  86         return size() << 2;
  87     }
  88 };
  89
  90 class AtagCore : public AtagHeader
  91 {
  92   public:
  93     static const uint32_t Size = 5;
  94     uint32_t tag() { return CoreTag; }
  95
  96     void flags(uint32_t i) { storage[2] = i; }
  97     void pagesize(uint32_t i) { storage[3] = i; }
  98     void rootdev(uint32_t i) { storage[4] = i; }
  99     AtagCore()
 100         : AtagHeader(Size)
 101     {}
 102 };
 103
 104 class AtagMem : public AtagHeader
 105 {
 106   public:
 107     static const uint32_t Size = 4;
 108     uint32_t tag() { return MemTag; }
 109
 110     void memSize(uint32_t i) { storage[2] = i; }
 111     void memStart(uint32_t i) { storage[3] = i; }
 112     AtagMem()
 113         : AtagHeader(Size)
 114     {}
 115 };
 116
 117 class AtagRev : public AtagHeader
 118 {
 119   public:
 120     static const uint32_t Size = 3;
 121     uint32_t tag() { return RevTag; }
 122
 123     void rev(uint32_t i) { storage[2] = i; }
 124     AtagRev()
 125         : AtagHeader(Size)
 126     {}
 127 };
 128
 129
 130 class AtagSerial : public AtagHeader
 131 {
 132   public:
 133     static const uint32_t Size = 4;
 134     uint32_t tag() { return SerialTag; }
 135
 136     void sn(uint64_t i) { storage[2] = (uint32_t)i; storage[3] = i >> 32; }
 137     AtagSerial()
 138         : AtagHeader(Size)
 139     {}
 140 };
 141
 142 class AtagCmdline : public AtagHeader
 143 {
 144   public:
 145     static const uint32_t Size = 3;
 146     uint32_t tag() { return CmdTag; }
 147
 148     void cmdline(const std::string &s)
 149     {
 150         // Add one for null terminator
 151         int len = s.length() + 1;
 152
 153         // 2 + ceiling(len/4)
 154         _size = 2 + ((len + 3) >> 2);
 155
 156         delete[] storage;
 157         storage = new uint32_t[size()];
 158
 159         strcpy((char*)&storage[2] , s.c_str());
 160     }
 161     AtagCmdline()
 162         : AtagHeader(Size)
 163     {}
 164 };
 165
 166 class AtagNone : public AtagHeader
 167 {
 168   public:
 169     static const uint32_t Size = 2;
 170     virtual bool null() { return true; }
 171     uint32_t tag() { return NoneTag; }
 172     AtagNone()
 173         : AtagHeader(Size)
 174     {}
 175 };
 176 /*
 177 //
 178 // example ARM Linux bootloader code
 179 // this example is distributed under the BSD licence
 180 // Code taken from http://www.simtec.co.uk/products/SWLINUX/files/booting_article.html
 181 ///
 182
 183 // list of possible tags
 184 #define ATAG_NONE       0x00000000
 185 #define ATAG_CORE       0x54410001
 186 #define ATAG_MEM        0x54410002
 187 #define ATAG_VIDEOTEXT  0x54410003
 188 #define ATAG_RAMDISK    0x54410004
 189 #define ATAG_INITRD2    0x54420005
 190 #define ATAG_SERIAL     0x54410006
 191 #define ATAG_REVISION   0x54410007
 192 #define ATAG_VIDEOLFB   0x54410008
 193 #define ATAG_CMDLINE    0x54410009
 194
 195 // structures for each atag
 196 struct atag_header {
 197         u32 size; // length of tag in words including this header
 198         u32 tag;  // tag type
 199 };
 200
 201 struct atag_core {
 202         u32 flags;
 203         u32 pagesize;
 204         u32 rootdev;
 205 };
 206
 207 struct atag_mem {
 208         u32     size;
 209         u32     start;
 210 };
 211
 212 struct atag_videotext {
 213         u8              x;
 214         u8              y;
 215         u16             video_page;
 216         u8              video_mode;
 217         u8              video_cols;
 218         u16             video_ega_bx;
 219         u8              video_lines;
 220         u8              video_isvga;
 221         u16             video_points;
 222 };
 223
 224 struct atag_ramdisk {
 225         u32 flags;
 226         u32 size;
 227         u32 start;
 228 };
 229
 230 struct atag_initrd2 {
 231         u32 start;
 232         u32 size;
 233 };
 234
 235 struct atag_serialnr {
 236         u32 low;
 237         u32 high;
 238 };
 239
 240 struct atag_revision {
 241         u32 rev;
 242 };
 243
 244 struct atag_videolfb {
 245         u16             lfb_width;
 246         u16             lfb_height;
 247         u16             lfb_depth;
 248         u16             lfb_linelength;
 249         u32             lfb_base;
 250         u32             lfb_size;
 251         u8              red_size;
 252         u8              red_pos;
 253         u8              green_size;
 254         u8              green_pos;
 255         u8              blue_size;
 256         u8              blue_pos;
 257         u8              rsvd_size;
 258         u8              rsvd_pos;
 259 };
 260
 261 struct atag_cmdline {
 262         char    cmdline[1];
 263 };
 264
 265 struct atag {
 266         struct atag_header hdr;
 267         union {
 268                 struct atag_core         core;
 269                 struct atag_mem          mem;
 270                 struct atag_videotext    videotext;
 271                 struct atag_ramdisk      ramdisk;
 272                 struct atag_initrd2      initrd2;
 273                 struct atag_serialnr     serialnr;
 274                 struct atag_revision     revision;
 275                 struct atag_videolfb     videolfb;
 276                 struct atag_cmdline      cmdline;
 277         } u;
 278 };
 279 */
 280
 281
 282 #endif // __ARCH_ARM_LINUX_ATAG_HH__