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slot ROM checksum is recalculated after patching during resolution switch

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This commit is contained in:
cebix 2001-06-29 12:51:21 +00:00
parent d011594d4e
commit 738fa25344
3 changed files with 38 additions and 14 deletions
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1
BasiliskII/src/include/slot_rom.h
View File

@ -22,5 +22,6 @@
#define SLOT_ROM_H
extern bool InstallSlotROM(void);
extern void ChecksumSlotROM(void);
#endif

45
BasiliskII/src/slot_rom.cpp
View File

@ -42,6 +42,9 @@ static uint8 srom[4096];
// Index in srom
static uint32 p;
// Length of slot ROM
static int slot_rom_size = 0;
// Check whether a mode with the specified depth exists
static bool has_depth(video_depth depth)
@ -433,23 +436,39 @@ bool InstallSlotROM(void)
// Format/header block
Offs(0, sRsrcDir); // sResource directory
Long(p + 16); // Length of declaration data
Long(0); // CRC (calculated below)
Long(0); // CRC (calculated later)
Word(0x0101); // Rev. level, format
Long(0x5a932bc7); // Test pattern
Word(0x000f); // Byte lanes
// Calculate CRC
uint32 crc = 0;
for (uint32 i=0; i<p; i++) {
crc = (crc << 1) | (crc >> 31);
crc += srom[i];
}
srom[p - 12] = crc >> 24;
srom[p - 11] = crc >> 16;
srom[p - 10] = crc >> 8;
srom[p - 9] = crc;
// Copy slot ROM to Mac ROM
memcpy(ROMBaseHost + ROMSize - p, srom, p);
slot_rom_size = p;
memcpy(ROMBaseHost + ROMSize - slot_rom_size, srom, slot_rom_size);
// Calculate checksum
ChecksumSlotROM();
return true;
}
/*
* Calculate slot ROM checksum (in-place)
*/
void ChecksumSlotROM(void)
{
// Calculate CRC
uint8 *p = ROMBaseHost + ROMSize - slot_rom_size;
p[slot_rom_size - 12] = 0;
p[slot_rom_size - 11] = 0;
p[slot_rom_size - 10] = 0;
p[slot_rom_size - 9] = 0;
uint32 crc = 0;
for (uint32 i=0; i<slot_rom_size; i++) {
crc = (crc << 1) | (crc >> 31);
crc += p[i];
}
p[slot_rom_size - 12] = crc >> 24;
p[slot_rom_size - 11] = crc >> 16;
p[slot_rom_size - 10] = crc >> 8;
p[slot_rom_size - 9] = crc;
}

6
BasiliskII/src/video.cpp
View File

@ -31,6 +31,7 @@
#include "cpu_emulation.h"
#include "main.h"
#include "macos_util.h"
#include "slot_rom.h"
#include "video.h"
#include "video_defs.h"
@ -349,7 +350,7 @@ int16 VideoDriverControl(uint32 pb, uint32 dce)
Execute68kTrap(0xa06e, &r); // SRsrcInfo()
uint32 rsrc = ReadMacInt32(sp + spPointer);
// Patch minorBase
// Patch minorBase (otherwise rebooting won't work)
WriteMacInt8(sp + spID, 0x0a); // minorBase
r.d[0] = 0x0006;
Execute68kTrap(0xa06e, &r); // SFindStruct()
@ -375,6 +376,9 @@ int16 VideoDriverControl(uint32 pb, uint32 dce)
ROMBaseHost[p + 16] = i->x >> 8;
ROMBaseHost[p + 17] = i->x;
// Recalculate slot ROM checksum
ChecksumSlotROM();
// Update sResource
WriteMacInt8(sp + spID, ReadMacInt8(dce + dCtlSlotId));
r.d[0] = 0x002b;