boot/freeldr/freeldr/arch/i386/xboxmem.c

   1 /*
   2  *  FreeLoader
   3  *
   4  *  This program is free software; you can redistribute it and/or modify
   5  *  it under the terms of the GNU General Public License as published by
   6  *  the Free Software Foundation; either version 2 of the License, or
   7  *  (at your option) any later version.
   8  *
   9  *  This program is distributed in the hope that it will be useful,
  10  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  *  GNU General Public License for more details.
  13  *
  14  *  You should have received a copy of the GNU General Public License along
  15  *  with this program; if not, write to the Free Software Foundation, Inc.,
  16  *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  *  Note: much of this code was based on knowledge and/or code developed
  19  *  by the Xbox Linux group: http://www.xbox-linux.org
  20  */
  21
  22 #include <freeldr.h>
  23 #include <debug.h>
  24
  25 DBG_DEFAULT_CHANNEL(MEMORY);
  26
  27 static ULONG InstalledMemoryMb = 0;
  28 static ULONG AvailableMemoryMb = 0;
  29
  30 #define TEST_SIZE     0x200
  31 #define TEST_PATTERN1 0xAA
  32 #define TEST_PATTERN2 0x55
  33
  34 extern VOID
  35 SetMemory(
  36     PFREELDR_MEMORY_DESCRIPTOR MemoryMap,
  37     ULONG_PTR BaseAddress,
  38     SIZE_T Size,
  39     TYPE_OF_MEMORY MemoryType);
  40
  41 extern ULONG
  42 PcMemFinalizeMemoryMap(
  43     PFREELDR_MEMORY_DESCRIPTOR MemoryMap);
  44
  45 VOID
  46 XboxMemInit(VOID)
  47 {
  48     UCHAR ControlRegion[TEST_SIZE];
  49     PVOID MembaseTop = (PVOID)(64 * 1024 * 1024);
  50     PVOID MembaseLow = (PVOID)0;
  51
  52     (*(PULONG)(0xfd000000 + 0x100200)) = 0x03070103;
  53     (*(PULONG)(0xfd000000 + 0x100204)) = 0x11448000;
  54
  55     WRITE_PORT_ULONG((ULONG*) 0xcf8, CONFIG_CMD(0, 0, 0x84));
  56     WRITE_PORT_ULONG((ULONG*) 0xcfc, 0x7ffffff);             /* Prep hardware for 128 Mb */
  57
  58     InstalledMemoryMb = 64;
  59     memset(ControlRegion, TEST_PATTERN1, TEST_SIZE);
  60     memset(MembaseTop, TEST_PATTERN1, TEST_SIZE);
  61     __wbinvd();
  62
  63     if (memcmp(MembaseTop, ControlRegion, TEST_SIZE) == 0)
  64     {
  65         /* Looks like there is memory .. maybe a 128MB box */
  66         memset(ControlRegion, TEST_PATTERN2, TEST_SIZE);
  67         memset(MembaseTop, TEST_PATTERN2, TEST_SIZE);
  68         __wbinvd();
  69         if (memcmp(MembaseTop, ControlRegion, TEST_SIZE) == 0)
  70         {
  71             /* Definitely looks like there is memory */
  72             if (memcmp(MembaseLow, ControlRegion, TEST_SIZE) == 0)
  73             {
  74                 /* Hell, we find the Test-string at 0x0 too! */
  75                 InstalledMemoryMb = 64;
  76             }
  77             else
  78             {
  79                 InstalledMemoryMb = 128;
  80             }
  81         }
  82     }
  83
  84     /* Set hardware for amount of memory detected */
  85     WRITE_PORT_ULONG((ULONG*) 0xcf8, CONFIG_CMD(0, 0, 0x84));
  86     WRITE_PORT_ULONG((ULONG*) 0xcfc, InstalledMemoryMb * 1024 * 1024 - 1);
  87
  88     /* 4 MB video framebuffer is reserved later using XboxMemReserveMemory() */
  89     AvailableMemoryMb = InstalledMemoryMb;
  90 }
  91
  92 FREELDR_MEMORY_DESCRIPTOR XboxMemoryMap[2];
  93
  94 PFREELDR_MEMORY_DESCRIPTOR
  95 XboxMemGetMemoryMap(ULONG *MemoryMapSize)
  96 {
  97     TRACE("XboxMemGetMemoryMap()\n");
  98
  99     /* Synthesize memory map */
 100
 101     /* Available RAM block */
 102     SetMemory(XboxMemoryMap,
 103               0,
 104               AvailableMemoryMb * 1024 * 1024,
 105               LoaderFree);
 106
 107     /* Video memory */
 108     SetMemory(XboxMemoryMap,
 109               AvailableMemoryMb * 1024 * 1024,
 110               (InstalledMemoryMb - AvailableMemoryMb) * 1024 * 1024,
 111               LoaderFirmwarePermanent);
 112
 113     *MemoryMapSize = PcMemFinalizeMemoryMap(XboxMemoryMap);
 114     return XboxMemoryMap;
 115 }
 116
 117 PVOID
 118 XboxMemReserveMemory(ULONG MbToReserve)
 119 {
 120     /* This function is used to reserve video framebuffer in XboxVideoInit() */
 121
 122     if (InstalledMemoryMb == 0)
 123     {
 124         /* Hmm, seems we're not initialized yet */
 125         XboxMemInit();
 126     }
 127
 128     if (MbToReserve > AvailableMemoryMb)
 129     {
 130         /* Can't satisfy the request */
 131         return NULL;
 132     }
 133
 134     AvailableMemoryMb -= MbToReserve;
 135
 136     /* Top of available memory points to the space just reserved */
 137     return (PVOID)(AvailableMemoryMb * 1024 * 1024);
 138 }
 139
 140 /* EOF */