gem5/src/arch/arm/isa.cc
Ali Saidi e097c4fb18 ARM: Remove the saturating (Q) condition code from the renamed register.
Move the saturating bit (which is also saturating) from the renamed register
that holds the flags to the CPSR miscreg and adds a allows setting it in a
similar way to the FP saturating registers. This removes a dependency in
instructions that don't write, but need to preserve the Q bit.
2011-05-13 17:27:01 -05:00

523 lines
18 KiB
C++

/*
* Copyright (c) 2010 ARM Limited
* All rights reserved
*
* The license below extends only to copyright in the software and shall
* not be construed as granting a license to any other intellectual
* property including but not limited to intellectual property relating
* to a hardware implementation of the functionality of the software
* licensed hereunder. You may use the software subject to the license
* terms below provided that you ensure that this notice is replicated
* unmodified and in its entirety in all distributions of the software,
* modified or unmodified, in source code or in binary form.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are
* met: redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer;
* redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution;
* neither the name of the copyright holders nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* Authors: Gabe Black
* Ali Saidi
*/
#include "arch/arm/isa.hh"
#include "debug/Arm.hh"
#include "debug/MiscRegs.hh"
#include "sim/faults.hh"
#include "sim/stat_control.hh"
#include "sim/system.hh"
namespace ArmISA
{
void
ISA::clear()
{
SCTLR sctlr_rst = miscRegs[MISCREG_SCTLR_RST];
uint32_t midr = miscRegs[MISCREG_MIDR];
memset(miscRegs, 0, sizeof(miscRegs));
CPSR cpsr = 0;
cpsr.mode = MODE_USER;
miscRegs[MISCREG_CPSR] = cpsr;
updateRegMap(cpsr);
SCTLR sctlr = 0;
sctlr.te = (bool)sctlr_rst.te;
sctlr.nmfi = (bool)sctlr_rst.nmfi;
sctlr.v = (bool)sctlr_rst.v;
sctlr.u = 1;
sctlr.xp = 1;
sctlr.rao2 = 1;
sctlr.rao3 = 1;
sctlr.rao4 = 1;
miscRegs[MISCREG_SCTLR] = sctlr;
miscRegs[MISCREG_SCTLR_RST] = sctlr_rst;
// Preserve MIDR accross reset
miscRegs[MISCREG_MIDR] = midr;
/* Start with an event in the mailbox */
miscRegs[MISCREG_SEV_MAILBOX] = 1;
// Separate Instruction and Data TLBs.
miscRegs[MISCREG_TLBTR] = 1;
MVFR0 mvfr0 = 0;
mvfr0.advSimdRegisters = 2;
mvfr0.singlePrecision = 2;
mvfr0.doublePrecision = 2;
mvfr0.vfpExceptionTrapping = 0;
mvfr0.divide = 1;
mvfr0.squareRoot = 1;
mvfr0.shortVectors = 1;
mvfr0.roundingModes = 1;
miscRegs[MISCREG_MVFR0] = mvfr0;
MVFR1 mvfr1 = 0;
mvfr1.flushToZero = 1;
mvfr1.defaultNaN = 1;
mvfr1.advSimdLoadStore = 1;
mvfr1.advSimdInteger = 1;
mvfr1.advSimdSinglePrecision = 1;
mvfr1.advSimdHalfPrecision = 1;
mvfr1.vfpHalfPrecision = 1;
miscRegs[MISCREG_MVFR1] = mvfr1;
miscRegs[MISCREG_MPIDR] = 0;
// Reset values of PRRR and NMRR are implementation dependent
miscRegs[MISCREG_PRRR] =
(1 << 19) | // 19
(0 << 18) | // 18
(0 << 17) | // 17
(1 << 16) | // 16
(2 << 14) | // 15:14
(0 << 12) | // 13:12
(2 << 10) | // 11:10
(2 << 8) | // 9:8
(2 << 6) | // 7:6
(2 << 4) | // 5:4
(1 << 2) | // 3:2
0; // 1:0
miscRegs[MISCREG_NMRR] =
(1 << 30) | // 31:30
(0 << 26) | // 27:26
(0 << 24) | // 25:24
(3 << 22) | // 23:22
(2 << 20) | // 21:20
(0 << 18) | // 19:18
(0 << 16) | // 17:16
(1 << 14) | // 15:14
(0 << 12) | // 13:12
(2 << 10) | // 11:10
(0 << 8) | // 9:8
(3 << 6) | // 7:6
(2 << 4) | // 5:4
(0 << 2) | // 3:2
0; // 1:0
miscRegs[MISCREG_CPACR] = 0;
miscRegs[MISCREG_FPSID] = 0x410430A0;
// See section B4.1.84 of ARM ARM
// All values are latest for ARMv7-A profile
miscRegs[MISCREG_ID_ISAR0] = 0x01101111;
miscRegs[MISCREG_ID_ISAR1] = 0x02112111;
miscRegs[MISCREG_ID_ISAR2] = 0x21232141;
miscRegs[MISCREG_ID_ISAR3] = 0x01112131;
miscRegs[MISCREG_ID_ISAR4] = 0x10010142;
miscRegs[MISCREG_ID_ISAR5] = 0x00000000;
//XXX We need to initialize the rest of the state.
}
MiscReg
ISA::readMiscRegNoEffect(int misc_reg)
{
assert(misc_reg < NumMiscRegs);
int flat_idx;
if (misc_reg == MISCREG_SPSR)
flat_idx = flattenMiscIndex(misc_reg);
else
flat_idx = misc_reg;
MiscReg val = miscRegs[flat_idx];
DPRINTF(MiscRegs, "Reading From misc reg %d (%d) : %#x\n",
misc_reg, flat_idx, val);
return val;
}
MiscReg
ISA::readMiscReg(int misc_reg, ThreadContext *tc)
{
if (misc_reg == MISCREG_CPSR) {
CPSR cpsr = miscRegs[misc_reg];
PCState pc = tc->pcState();
cpsr.j = pc.jazelle() ? 1 : 0;
cpsr.t = pc.thumb() ? 1 : 0;
return cpsr;
}
if (misc_reg >= MISCREG_CP15_UNIMP_START)
panic("Unimplemented CP15 register %s read.\n",
miscRegName[misc_reg]);
switch (misc_reg) {
case MISCREG_MPIDR:
return tc->cpuId();
break;
case MISCREG_ID_MMFR3:
return 0xF0102211; // SuperSec | Coherent TLB | Bcast Maint |
// BP Maint | Cache Maint Set/way | Cache Maint MVA
case MISCREG_CLIDR:
warn_once("The clidr register always reports 0 caches.\n");
break;
case MISCREG_CCSIDR:
warn_once("The ccsidr register isn't implemented and "
"always reads as 0.\n");
break;
case MISCREG_ID_PFR0:
warn("Returning thumbEE disabled for now since we don't support CP14"
"config registers and jumping to ThumbEE vectors\n");
return 0x0031; // !ThumbEE | !Jazelle | Thumb | ARM
case MISCREG_ID_PFR1:
warn("reading unimplmented register ID_PFR1");
return 0;
case MISCREG_ID_MMFR0:
return 0x03; //VMSAz7
case MISCREG_CTR:
return 0x86468006; // V7, 64 byte cache line, load/exclusive is exact
case MISCREG_ACTLR:
warn("Not doing anything for miscreg ACTLR\n");
break;
case MISCREG_PMCR:
case MISCREG_PMCCNTR:
case MISCREG_PMSELR:
warn("Not doing anything for read to miscreg %s\n",
miscRegName[misc_reg]);
break;
case MISCREG_CPSR_Q:
panic("shouldn't be reading this register seperately\n");
case MISCREG_FPSCR_QC:
return readMiscRegNoEffect(MISCREG_FPSCR) & ~FpscrQcMask;
case MISCREG_FPSCR_EXC:
return readMiscRegNoEffect(MISCREG_FPSCR) & ~FpscrExcMask;
}
return readMiscRegNoEffect(misc_reg);
}
void
ISA::setMiscRegNoEffect(int misc_reg, const MiscReg &val)
{
assert(misc_reg < NumMiscRegs);
int flat_idx;
if (misc_reg == MISCREG_SPSR)
flat_idx = flattenMiscIndex(misc_reg);
else
flat_idx = misc_reg;
miscRegs[flat_idx] = val;
DPRINTF(MiscRegs, "Writing to misc reg %d (%d) : %#x\n", misc_reg,
flat_idx, val);
}
void
ISA::setMiscReg(int misc_reg, const MiscReg &val, ThreadContext *tc)
{
MiscReg newVal = val;
int x;
System *sys;
ThreadContext *oc;
if (misc_reg == MISCREG_CPSR) {
updateRegMap(val);
CPSR old_cpsr = miscRegs[MISCREG_CPSR];
int old_mode = old_cpsr.mode;
CPSR cpsr = val;
if (old_mode != cpsr.mode) {
tc->getITBPtr()->invalidateMiscReg();
tc->getDTBPtr()->invalidateMiscReg();
}
DPRINTF(Arm, "Updating CPSR from %#x to %#x f:%d i:%d a:%d mode:%#x\n",
miscRegs[misc_reg], cpsr, cpsr.f, cpsr.i, cpsr.a, cpsr.mode);
PCState pc = tc->pcState();
pc.nextThumb(cpsr.t);
pc.nextJazelle(cpsr.j);
tc->pcState(pc);
} else if (misc_reg >= MISCREG_CP15_UNIMP_START &&
misc_reg < MISCREG_CP15_END) {
panic("Unimplemented CP15 register %s wrote with %#x.\n",
miscRegName[misc_reg], val);
} else {
switch (misc_reg) {
case MISCREG_CPACR:
{
const uint32_t ones = (uint32_t)(-1);
CPACR cpacrMask = 0;
// Only cp10, cp11, and ase are implemented, nothing else should
// be writable
cpacrMask.cp10 = ones;
cpacrMask.cp11 = ones;
cpacrMask.asedis = ones;
newVal &= cpacrMask;
DPRINTF(MiscRegs, "Writing misc reg %s: %#x\n",
miscRegName[misc_reg], newVal);
}
break;
case MISCREG_CSSELR:
warn_once("The csselr register isn't implemented.\n");
return;
case MISCREG_FPSCR:
{
const uint32_t ones = (uint32_t)(-1);
FPSCR fpscrMask = 0;
fpscrMask.ioc = ones;
fpscrMask.dzc = ones;
fpscrMask.ofc = ones;
fpscrMask.ufc = ones;
fpscrMask.ixc = ones;
fpscrMask.idc = ones;
fpscrMask.len = ones;
fpscrMask.stride = ones;
fpscrMask.rMode = ones;
fpscrMask.fz = ones;
fpscrMask.dn = ones;
fpscrMask.ahp = ones;
fpscrMask.qc = ones;
fpscrMask.v = ones;
fpscrMask.c = ones;
fpscrMask.z = ones;
fpscrMask.n = ones;
newVal = (newVal & (uint32_t)fpscrMask) |
(miscRegs[MISCREG_FPSCR] & ~(uint32_t)fpscrMask);
}
break;
case MISCREG_CPSR_Q:
{
assert(!(newVal & ~CpsrMaskQ));
newVal = miscRegs[MISCREG_CPSR] | newVal;
misc_reg = MISCREG_CPSR;
}
break;
case MISCREG_FPSCR_QC:
{
newVal = miscRegs[MISCREG_FPSCR] | (newVal & FpscrQcMask);
misc_reg = MISCREG_FPSCR;
}
break;
case MISCREG_FPSCR_EXC:
{
newVal = miscRegs[MISCREG_FPSCR] | (newVal & FpscrExcMask);
misc_reg = MISCREG_FPSCR;
}
break;
case MISCREG_FPEXC:
{
// vfpv3 architecture, section B.6.1 of DDI04068
// bit 29 - valid only if fpexc[31] is 0
const uint32_t fpexcMask = 0x60000000;
newVal = (newVal & fpexcMask) |
(miscRegs[MISCREG_FPEXC] & ~fpexcMask);
}
break;
case MISCREG_SCTLR:
{
DPRINTF(MiscRegs, "Writing SCTLR: %#x\n", newVal);
SCTLR sctlr = miscRegs[MISCREG_SCTLR];
SCTLR new_sctlr = newVal;
new_sctlr.nmfi = (bool)sctlr.nmfi;
miscRegs[MISCREG_SCTLR] = (MiscReg)new_sctlr;
tc->getITBPtr()->invalidateMiscReg();
tc->getDTBPtr()->invalidateMiscReg();
return;
}
case MISCREG_TLBTR:
case MISCREG_MVFR0:
case MISCREG_MVFR1:
case MISCREG_MPIDR:
case MISCREG_FPSID:
return;
case MISCREG_TLBIALLIS:
case MISCREG_TLBIALL:
sys = tc->getSystemPtr();
for (x = 0; x < sys->numContexts(); x++) {
oc = sys->getThreadContext(x);
assert(oc->getITBPtr() && oc->getDTBPtr());
oc->getITBPtr()->flushAll();
oc->getDTBPtr()->flushAll();
}
return;
case MISCREG_ITLBIALL:
tc->getITBPtr()->flushAll();
return;
case MISCREG_DTLBIALL:
tc->getDTBPtr()->flushAll();
return;
case MISCREG_TLBIMVAIS:
case MISCREG_TLBIMVA:
sys = tc->getSystemPtr();
for (x = 0; x < sys->numContexts(); x++) {
oc = sys->getThreadContext(x);
assert(oc->getITBPtr() && oc->getDTBPtr());
oc->getITBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
bits(newVal, 7,0));
oc->getDTBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
bits(newVal, 7,0));
}
return;
case MISCREG_TLBIASIDIS:
case MISCREG_TLBIASID:
sys = tc->getSystemPtr();
for (x = 0; x < sys->numContexts(); x++) {
oc = sys->getThreadContext(x);
assert(oc->getITBPtr() && oc->getDTBPtr());
oc->getITBPtr()->flushAsid(bits(newVal, 7,0));
oc->getDTBPtr()->flushAsid(bits(newVal, 7,0));
}
return;
case MISCREG_TLBIMVAAIS:
case MISCREG_TLBIMVAA:
sys = tc->getSystemPtr();
for (x = 0; x < sys->numContexts(); x++) {
oc = sys->getThreadContext(x);
assert(oc->getITBPtr() && oc->getDTBPtr());
oc->getITBPtr()->flushMva(mbits(newVal, 31,12));
oc->getDTBPtr()->flushMva(mbits(newVal, 31,12));
}
return;
case MISCREG_ITLBIMVA:
tc->getITBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
bits(newVal, 7,0));
return;
case MISCREG_DTLBIMVA:
tc->getDTBPtr()->flushMvaAsid(mbits(newVal, 31, 12),
bits(newVal, 7,0));
return;
case MISCREG_ITLBIASID:
tc->getITBPtr()->flushAsid(bits(newVal, 7,0));
return;
case MISCREG_DTLBIASID:
tc->getDTBPtr()->flushAsid(bits(newVal, 7,0));
return;
case MISCREG_ACTLR:
warn("Not doing anything for write of miscreg ACTLR\n");
break;
case MISCREG_PMCR:
{
// Performance counters not implemented. Instead, interpret
// a reset command to this register to reset the simulator
// statistics.
// PMCR_E | PMCR_P | PMCR_C
const int ResetAndEnableCounters = 0x7;
if (newVal == ResetAndEnableCounters) {
inform("Resetting all simobject stats\n");
Stats::schedStatEvent(false, true);
break;
}
}
case MISCREG_PMCCNTR:
case MISCREG_PMSELR:
warn("Not doing anything for write to miscreg %s\n",
miscRegName[misc_reg]);
break;
case MISCREG_V2PCWPR:
case MISCREG_V2PCWPW:
case MISCREG_V2PCWUR:
case MISCREG_V2PCWUW:
case MISCREG_V2POWPR:
case MISCREG_V2POWPW:
case MISCREG_V2POWUR:
case MISCREG_V2POWUW:
{
RequestPtr req = new Request;
unsigned flags;
BaseTLB::Mode mode;
Fault fault;
switch(misc_reg) {
case MISCREG_V2PCWPR:
flags = TLB::MustBeOne;
mode = BaseTLB::Read;
break;
case MISCREG_V2PCWPW:
flags = TLB::MustBeOne;
mode = BaseTLB::Write;
break;
case MISCREG_V2PCWUR:
flags = TLB::MustBeOne | TLB::UserMode;
mode = BaseTLB::Read;
break;
case MISCREG_V2PCWUW:
flags = TLB::MustBeOne | TLB::UserMode;
mode = BaseTLB::Write;
break;
default:
panic("Security Extensions not implemented!");
}
warn("Translating via MISCREG in atomic mode! Fix Me!\n");
req->setVirt(0, val, 1, flags, tc->pcState().pc());
fault = tc->getDTBPtr()->translateAtomic(req, tc, mode);
if (fault == NoFault) {
miscRegs[MISCREG_PAR] =
(req->getPaddr() & 0xfffff000) |
(tc->getDTBPtr()->getAttr() );
DPRINTF(MiscRegs,
"MISCREG: Translated addr 0x%08x: PAR: 0x%08x\n",
val, miscRegs[MISCREG_PAR]);
}
else {
// Set fault bit and FSR
FSR fsr = miscRegs[MISCREG_DFSR];
miscRegs[MISCREG_PAR] =
(fsr.ext << 6) |
(fsr.fsHigh << 5) |
(fsr.fsLow << 1) |
0x1; // F bit
}
return;
}
case MISCREG_CONTEXTIDR:
case MISCREG_PRRR:
case MISCREG_NMRR:
case MISCREG_DACR:
tc->getITBPtr()->invalidateMiscReg();
tc->getDTBPtr()->invalidateMiscReg();
break;
case MISCREG_CPSR_MODE:
// This miscreg is used by copy*Regs to set the CPSR mode
// without updating other CPSR variables. It's used to
// make sure the register map is in such a state that we can
// see all of the registers for the copy.
updateRegMap(val);
return;
}
}
setMiscRegNoEffect(misc_reg, newVal);
}
}