dingusppc/cpu/ppc/ppcexceptions.cpp
Maxim Poliakovski 461d859e73 ppcmmu: add debug memory reading function.
This function saves and restores the MMU state
so no invalid user input can break CPU execution.
2020-02-23 16:41:58 +01:00

157 lines
5.1 KiB
C++

/** @file Handling of low-level PPC exceptions. */
#include <setjmp.h>
#include <string>
#include <stdexcept>
#include "ppcemu.h"
jmp_buf exc_env; /* Global exception environment. */
[[noreturn]] void ppc_exception_handler(Except_Type exception_type,
uint32_t srr1_bits)
{
grab_exception = true;
#ifdef PROFILER
exceptions_performed++;
#endif
bb_kind = BB_end_kind::BB_EXCEPTION;
switch(exception_type) {
case Except_Type::EXC_SYSTEM_RESET:
ppc_state.ppc_spr[SPR::SRR0] = ppc_cur_instruction & 0xFFFFFFFC;
ppc_next_instruction_address = 0x0100;
break;
case Except_Type::EXC_MACHINE_CHECK:
if (!(ppc_state.ppc_msr & 0x1000)) {
/* TODO: handle internal checkstop */
}
ppc_state.ppc_spr[SPR::SRR0] = ppc_cur_instruction & 0xFFFFFFFC;
ppc_next_instruction_address = 0x0200;
break;
case Except_Type::EXC_DSI:
ppc_state.ppc_spr[SPR::SRR0] = ppc_cur_instruction & 0xFFFFFFFC;
ppc_next_instruction_address = 0x0300;
break;
case Except_Type::EXC_ISI:
ppc_state.ppc_spr[SPR::SRR0] = ppc_next_instruction_address;
ppc_next_instruction_address = 0x0400;
break;
case Except_Type::EXC_EXT_INT:
ppc_state.ppc_spr[SPR::SRR0] = ppc_next_instruction_address;
ppc_next_instruction_address = 0x0500;
break;
case Except_Type::EXC_ALIGNMENT:
ppc_state.ppc_spr[SPR::SRR0] = ppc_cur_instruction & 0xFFFFFFFC;
ppc_next_instruction_address = 0x0600;
break;
case Except_Type::EXC_PROGRAM:
ppc_state.ppc_spr[SPR::SRR0] = ppc_cur_instruction & 0xFFFFFFFC;
ppc_next_instruction_address = 0x0700;
break;
case Except_Type::EXC_NO_FPU:
ppc_state.ppc_spr[SPR::SRR0] = ppc_cur_instruction & 0xFFFFFFFC;
ppc_next_instruction_address = 0x0800;
break;
case Except_Type::EXC_DECR:
ppc_state.ppc_spr[SPR::SRR0] = (ppc_cur_instruction & 0xFFFFFFFC) + 4;
ppc_next_instruction_address = 0x0900;
break;
case Except_Type::EXC_SYSCALL:
ppc_state.ppc_spr[SPR::SRR0] = (ppc_cur_instruction & 0xFFFFFFFC) + 4;
ppc_next_instruction_address = 0x0C00;
break;
case Except_Type::EXC_TRACE:
ppc_state.ppc_spr[SPR::SRR0] = (ppc_cur_instruction & 0xFFFFFFFC) + 4;
ppc_next_instruction_address = 0x0D00;
break;
default:
//printf("Unknown exception occured: %X\n", exception_type);
//exit(-1);
break;
}
ppc_state.ppc_spr[SPR::SRR1] = (ppc_state.ppc_msr & 0x0000FF73) | srr1_bits;
ppc_state.ppc_msr &= 0xFFFB1041;
/* copy MSR[ILE] to MSR[LE] */
ppc_state.ppc_msr = (ppc_state.ppc_msr & 0xFFFFFFFE) |
((ppc_state.ppc_msr >> 16) & 1);
if (ppc_state.ppc_msr & 0x40) {
ppc_next_instruction_address |= 0xFFF00000;
}
longjmp(exc_env, 2); /* return to the main execution loop. */
}
[[noreturn]] void dbg_exception_handler(Except_Type exception_type,
uint32_t srr1_bits)
{
std::string exc_descriptor;
switch(exception_type) {
case Except_Type::EXC_SYSTEM_RESET:
exc_descriptor = "System reset exception occured";
break;
case Except_Type::EXC_MACHINE_CHECK:
exc_descriptor = "Machine check exception occured";
break;
case Except_Type::EXC_DSI:
case Except_Type::EXC_ISI:
if (ppc_state.ppc_spr[SPR::DSISR] & 0x40000000)
exc_descriptor = "DSI/ISI exception: unmapped memory access";
else if (ppc_state.ppc_spr[SPR::DSISR] & 0x08000000)
exc_descriptor = "DSI/ISI exception: access protection violation";
else {
if (exception_type == Except_Type::EXC_DSI)
exc_descriptor = "DSI exception";
else
exc_descriptor = "ISI exception";
}
break;
case Except_Type::EXC_EXT_INT:
exc_descriptor = "External interrupt exception occured";
break;
case Except_Type::EXC_ALIGNMENT:
exc_descriptor = "Alignment exception occured";
break;
case Except_Type::EXC_PROGRAM:
exc_descriptor = "Program exception occured";
break;
case Except_Type::EXC_NO_FPU:
exc_descriptor = "Floating-Point unavailable exception occured";
break;
case Except_Type::EXC_DECR:
exc_descriptor = "Decrementer exception occured";
break;
case Except_Type::EXC_SYSCALL:
exc_descriptor = "Syscall exception occured";
break;
case Except_Type::EXC_TRACE:
exc_descriptor = "Trace exception occured";
break;
}
throw std::invalid_argument(exc_descriptor);
}