Atmosphere/thermosphere/src/exceptions.c
2021-02-19 21:51:29 +00:00

129 lines
3.9 KiB
C

/*
* Copyright (c) 2019 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope 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 for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#include "hvc.h"
#include "traps.h"
#include "sysreg_traps.h"
#include "smc.h"
#include "core_ctx.h"
#include "debug_log.h"
bool spsrEvaluateConditionCode(u64 spsr, u32 conditionCode)
{
if (conditionCode == 14) {
// AL
return true;
} else if (conditionCode == 15) {
// Invalid encoding
return false;
}
// NZCV
bool n = (spsr & BIT(31)) != 0;
bool z = (spsr & BIT(30)) != 0;
bool c = (spsr & BIT(29)) != 0;
bool v = (spsr & BIT(28)) != 0;
bool tableHalf[] = {
// EQ, CS, MI, VS, HI, GE, GT
z, c, n, v, c && !z, n == v, !z && n == v,
};
return (conditionCode & 1) == 0 ? tableHalf[conditionCode / 2] : !tableHalf[conditionCode / 2];
}
void dumpStackFrame(const ExceptionStackFrame *frame, bool sameEl)
{
#ifndef NDEBUG
for (u32 i = 0; i < 30; i += 2) {
DEBUG("x%u\t\t%016llx\t\tx%u\t\t%016llx\n", i, frame->x[i], i + 1, frame->x[i + 1]);
}
DEBUG("x30\t\t%016llx\n\n", frame->x[30]);
DEBUG("elr_el2\t\t%016llx\n", frame->elr_el2);
DEBUG("spsr_el2\t%016llx\n", frame->spsr_el2);
if (sameEl) {
DEBUG("sp_el2\t\t%016llx\n", frame->sp_el2);
} else {
DEBUG("sp_el0\t\t%016llx\n", frame->sp_el0);
}
DEBUG("sp_el1\t\t%016llx\n", frame->sp_el1);
#else
(void)frame;
(void)sameEl;
#endif
}
static void advanceItState(ExceptionStackFrame *frame)
{
// Just in case EL0 is executing A32 (& not sure if fully supported)
if (!spsrIsThumb(frame->spsr_el2) || spsrGetT32ItFlags(frame->spsr_el2) == 0) {
return;
}
u32 it = spsrGetT32ItFlags(frame->spsr_el2);
// Last instruction of the block => wipe, otherwise advance
spsrSetT32ItFlags(&frame->spsr_el2, (it & 7) == 0 ? 0 : (it & 0xE0) | ((it << 1) & 0x1F));
}
void skipFaultingInstruction(ExceptionStackFrame *frame, u32 size)
{
advanceItState(frame);
frame->elr_el2 += size;
}
void handleLowerElSyncException(ExceptionStackFrame *frame, ExceptionSyndromeRegister esr)
{
switch (esr.ec) {
case Exception_CP15RTTrap:
case Exception_CP15RRTTrap:
case Exception_CP14RTTrap:
case Exception_CP14DTTrap:
case Exception_CP14RRTTrap: {
// A32 stub: Skip instruction, read 0 if necessary (there are debug regs at EL0)
handleSysregAccessA32Stub(frame, esr);
break;
}
case Exception_HypervisorCallA64:
handleHypercall(frame, esr);
break;
case Exception_MonitorCallA64:
handleSmcTrap(frame, esr);
break;
case Exception_SystemRegisterTrap:
handleMsrMrsTrap(frame, esr);
break;
default:
DEBUG("Lower EL sync exception, EC = 0x%02llx IL=%llu ISS=0x%06llx\n", (u64)esr.ec, esr.il, esr.iss);
dumpStackFrame(frame, false);
break;
}
}
void handleSameElSyncException(ExceptionStackFrame *frame, ExceptionSyndromeRegister esr)
{
DEBUG("Same EL sync exception on core %x, EC = 0x%02llx IL=%llu ISS=0x%06llx\n", currentCoreCtx->coreId, (u64)esr.ec, esr.il, esr.iss);
dumpStackFrame(frame, true);
}
void handleUnknownException(u32 offset)
{
DEBUG("Unknown exception on core %x! (offset 0x%03lx)\n", offset, currentCoreCtx->coreId);
}