Files
ppsspp/Core/MemMapFunctions.cpp
Henrik RydgårdandClaude Sonnet 5 28cbb3a967 Add the scratchpad's missing kernel-mode mirrors, fix a mask bug hiding them
The scratchpad (PSP's repurposed-cache scratch RAM, 0x00010000+) was only
mirrored for user-mode access (cached 0x00010000, uncached 0x40010000) -
kernel-mode code sees it at 0x80010000/0xC0010000 (the kernel bit,
0x80000000, is independent of and combinable with the uncached bit,
0x40000000 - not "the uncached bit" as an earlier doc note in this branch
mistakenly called it). Missing entirely from MemMap.cpp's views[] table,
causing a real SIGSEGV the first time kernel-mode code (flash0:/reboot.bin)
touched it.

Adding the two missing views wasn't sufficient: the scratchpad range check
is duplicated eight times (IsValidAddress/IsValid2AlignedAddress/
IsValid4AlignedAddress/MaxSizeAtAddress in MemMap.h, and four more in
MemMapFunctions.cpp), and all eight used a mask (0xBFFFC000) that cleared
the uncached bit but kept the kernel bit, rejecting 0x80010000 as invalid
before ever reaching the now-mapped memory. Fixed all eight to 0x3FFFC000,
matching Memory::MEMVIEW32_MASK (which the JIT backends already used
correctly for the equivalent runtime check).

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01GZq8ZtJmFY7bkX5FVkr3P9
2026-08-13 11:36:42 +02:00

170 lines
5.6 KiB
C++

// Copyright (C) 2003 Dolphin Project / 2012 PPSSPP Project
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0 or later versions.
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License 2.0 for more details.
// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/
// Official git repository and contact information can be found at
// https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/.
#include "Common/CommonTypes.h"
#include "Common/LogReporting.h"
#include "Core/Core.h"
#include "Core/MemMap.h"
#include "Core/Config.h"
#include "Core/ConfigValues.h"
#include "Core/MIPS/MIPS.h"
namespace Memory {
u8 *GetPointerWriteOrException(const u32 address) {
if ((address & 0x3E000000) == 0x08000000 || // RAM
(address & 0xBF800000) == 0x04000000 || // VRAM
(address & 0x3FFFC000) == 0x00010000 || // Scratchpad
((address & 0x3F000000) >= 0x08000000 && (address & 0x3F000000) < 0x08000000 + g_MemorySize)) { // More RAM (remasters, etc.)
return GetPointerWriteUnchecked(address);
} else {
// Size is not known, we pass 0 to signal that.
Core_MemoryException(address, 0, currentMIPS->pc, MemoryExceptionType::WRITE_BLOCK);
return nullptr;
}
}
const u8 *GetPointerOrException(const u32 address) {
if ((address & 0x3E000000) == 0x08000000 || // RAM
(address & 0xBF800000) == 0x04000000 || // VRAM
(address & 0x3FFFC000) == 0x00010000 || // Scratchpad
((address & 0x3F000000) >= 0x08000000 && (address & 0x3F000000) < 0x08000000 + g_MemorySize)) { // More RAM (remasters, etc.)
return GetPointerUnchecked(address);
} else {
// Size is not known, we pass 0 to signal that.
Core_MemoryException(address, 0, currentMIPS->pc, MemoryExceptionType::READ_BLOCK);
return nullptr;
}
}
u8 *GetPointerWriteRangeOrException(const u32 address, const u32 size) {
u8 *ptr = GetPointerWriteOrException(address);
if (ptr) {
if (ClampValidSizeAt(address, size) != size) {
// That's a memory exception! TODO: Adjust reported address to the end of the range?
Core_MemoryException(address, size, currentMIPS->pc, MemoryExceptionType::WRITE_BLOCK);
return nullptr;
} else {
return ptr;
}
} else {
// Error was handled in GetPointerWrite already, if we're not ignoring errors.
return nullptr;
}
}
const u8 *GetPointerRangeOrException(const u32 address, const u32 size) {
const u8 *ptr = GetPointerOrException(address);
if (ptr) {
if (ClampValidSizeAt(address, size) != size) {
// That's a memory exception! TODO: Adjust reported address to the end of the range?
Core_MemoryException(address, size, currentMIPS->pc, MemoryExceptionType::READ_BLOCK);
return nullptr;
} else {
return ptr;
}
} else {
// Error was handled in GetPointer already, if we're not ignoring errors.
return nullptr;
}
}
template <typename T>
inline void ReadMemoryOrException(T &var, const u32 address) {
if ((address & 0x3E000000) == 0x08000000 || // RAM
(address & 0xBF800000) == 0x04000000 || // VRAM
(address & 0x3FFFC000) == 0x00010000 || // Scratchpad
((address & 0x3F000000) >= 0x08000000 && (address & 0x3F000000) < 0x08000000 + g_MemorySize)) { // More RAM (remasters, etc.)
var = *((const T*)GetPointerUnchecked(address));
} else {
Core_MemoryException(address, sizeof(T), currentMIPS->pc, MemoryExceptionType::READ_WORD);
var = 0;
}
}
template <typename T>
inline void WriteMemoryOrException(u32 address, const T data) {
if ((address & 0x3E000000) == 0x08000000 || // RAM
(address & 0xBF800000) == 0x04000000 || // VRAM
(address & 0x3FFFC000) == 0x00010000 || // Scratchpad
((address & 0x3F000000) >= 0x08000000 && (address & 0x3F000000) < 0x08000000 + g_MemorySize)) { // More RAM (remasters, etc.)
*(T*)GetPointerUnchecked(address) = data;
} else {
Core_MemoryException(address, sizeof(T), currentMIPS->pc, MemoryExceptionType::WRITE_WORD);
}
}
bool IsRAMAddress(const u32 address) {
if ((address & 0x3E000000) == 0x08000000) {
return true;
} else if ((address & 0x3F000000) >= 0x08000000 && (address & 0x3F000000) < 0x08000000 + g_MemorySize) {
return true;
} else {
return false;
}
}
bool IsScratchpadAddress(const u32 address) {
// Ignore both the kernel bit (0x80000000) and the uncached bit (0x40000000) - the
// scratchpad is mirrored across all four combinations, same as RAM (see MemMap.cpp).
return (address & ~(0xC0000000 | (SCRATCHPAD_SIZE - 1))) == 0x00010000;
}
u8 ReadOrException_U8(const u32 address) {
u8 value = 0;
ReadMemoryOrException<u8>(value, address);
return (u8)value;
}
u16 ReadOrException_U16(const u32 address) {
u16_le value = 0;
ReadMemoryOrException<u16_le>(value, address);
return (u16)value;
}
u32 ReadOrException_U32(const u32 address) {
u32_le value = 0;
ReadMemoryOrException<u32_le>(value, address);
return value;
}
u64 ReadOrException_U64(const u32 address) {
u64_le value = 0;
ReadMemoryOrException<u64_le>(value, address);
return value;
}
void WriteOrException_U8(const u8 _Data, const u32 address) {
WriteMemoryOrException<u8>(address, _Data);
}
void WriteOrException_U16(const u16 _Data, const u32 address) {
WriteMemoryOrException<u16_le>(address, _Data);
}
void WriteOrException_U32(const u32 _Data, const u32 address) {
WriteMemoryOrException<u32_le>(address, _Data);
}
void WriteOrException_U64(const u64 _Data, const u32 address) {
WriteMemoryOrException<u64_le>(address, _Data);
}
} // namespace Memory