kvm: Add basic support for ARM

Architecture specific limitations:
 * LPAE is currently not supported by gem5. We therefore panic if LPAE
   is enabled when returning to gem5.
 * The co-processor based interface to the architected timer is
   unsupported. We can't support this due to limitations in the KVM
   API on ARM.
 * M5 ops are currently not supported. This requires either a kernel
   hack or a memory mapped device that handles the guest<->m5
   interface.
This commit is contained in:
Andreas Sandberg 2013-04-22 13:20:32 -04:00
parent 6d2941d990
commit f156020158
5 changed files with 914 additions and 0 deletions

View file

@ -953,6 +953,7 @@ if not have_kvm:
# Check if the requested target ISA is compatible with the host # Check if the requested target ISA is compatible with the host
def is_isa_kvm_compatible(isa): def is_isa_kvm_compatible(isa):
isa_comp_table = { isa_comp_table = {
"arm" : ( "armv7l" ),
} }
try: try:
import platform import platform

43
src/cpu/kvm/ArmKvmCPU.py Normal file
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@ -0,0 +1,43 @@
# Copyright (c) 2012 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: Andreas Sandberg
from m5.params import *
from BaseKvmCPU import BaseKvmCPU
class ArmKvmCPU(BaseKvmCPU):
type = 'ArmKvmCPU'
cxx_header = "cpu/kvm/arm_cpu.hh"

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@ -48,6 +48,10 @@ if env['USE_KVM']:
Source('perfevent.cc') Source('perfevent.cc')
Source('timer.cc') Source('timer.cc')
if env['TARGET_ISA'] == 'arm':
SimObject('ArmKvmCPU.py')
Source('arm_cpu.cc')
DebugFlag('Kvm', 'Basic KVM Functionality') DebugFlag('Kvm', 'Basic KVM Functionality')
DebugFlag('KvmContext', 'KVM/gem5 context synchronization') DebugFlag('KvmContext', 'KVM/gem5 context synchronization')
DebugFlag('KvmIO', 'KVM MMIO diagnostics') DebugFlag('KvmIO', 'KVM MMIO diagnostics')

705
src/cpu/kvm/arm_cpu.cc Normal file
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@ -0,0 +1,705 @@
/*
* Copyright (c) 2012 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: Andreas Sandberg
*/
#include <linux/kvm.h>
#include <algorithm>
#include <cerrno>
#include <memory>
#include "arch/registers.hh"
#include "cpu/kvm/arm_cpu.hh"
#include "cpu/kvm/base.hh"
#include "debug/Kvm.hh"
#include "debug/KvmContext.hh"
#include "debug/KvmInt.hh"
using namespace ArmISA;
#define EXTRACT_FIELD(val, mask, shift) \
(((val) & (mask)) >> (shift))
#define REG_IS_ARM(id) \
(((id) & KVM_REG_ARCH_MASK) == KVM_REG_ARM)
#define REG_IS_32BIT(id) \
(((id) & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32)
#define REG_IS_64BIT(id) \
(((id) & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64)
#define REG_IS_CP(id, cp) \
(((id) & KVM_REG_ARM_COPROC_MASK) == (cp))
#define REG_IS_CORE(id) REG_IS_CP((id), KVM_REG_ARM_CORE)
#define REG_IS_VFP(id) REG_IS_CP((id), KVM_REG_ARM_VFP)
#define REG_VFP_REG(id) ((id) & KVM_REG_ARM_VFP_MASK)
// HACK: These aren't really defined in any of the headers, so we'll
// assume some reasonable values for now.
#define REG_IS_VFP_REG(id) (REG_VFP_REG(id) < 0x100)
#define REG_IS_VFP_CTRL(id) (REG_VFP_REG(id) >= 0x100)
#define REG_IS_DEMUX(id) REG_IS_CP((id), KVM_REG_ARM_DEMUX)
// There is no constant in the kernel headers defining the mask to use
// to get the core register index. We'll just do what they do
// internally.
#define REG_CORE_IDX(id) \
(~(KVM_REG_ARCH_MASK | KVM_REG_SIZE_MASK | KVM_REG_ARM_CORE))
#define REG_CP(id) \
EXTRACT_FIELD(id, KVM_REG_ARM_COPROC_MASK, KVM_REG_ARM_COPROC_SHIFT)
#define REG_CRN(id) \
EXTRACT_FIELD(id, KVM_REG_ARM_32_CRN_MASK, KVM_REG_ARM_32_CRN_SHIFT)
#define REG_OPC1(id) \
EXTRACT_FIELD(id, KVM_REG_ARM_OPC1_MASK, KVM_REG_ARM_OPC1_SHIFT)
#define REG_CRM(id) \
EXTRACT_FIELD(id, KVM_REG_ARM_CRM_MASK, KVM_REG_ARM_CRM_SHIFT)
#define REG_OPC2(id) \
EXTRACT_FIELD(id, KVM_REG_ARM_32_OPC2_MASK, KVM_REG_ARM_32_OPC2_SHIFT)
#define REG_CP32(cpnum, crn, opc1, crm, opc2) ( \
(KVM_REG_ARM | KVM_REG_SIZE_U32) | \
((cpnum) << KVM_REG_ARM_COPROC_SHIFT) | \
((crn) << KVM_REG_ARM_32_CRN_SHIFT) | \
((opc1) << KVM_REG_ARM_OPC1_SHIFT) | \
((crm) << KVM_REG_ARM_CRM_SHIFT) | \
((opc2) << KVM_REG_ARM_32_OPC2_SHIFT))
#define REG_CP64(cpnum, opc1, crm) ( \
(KVM_REG_ARM | KVM_REG_SIZE_U64) | \
((cpnum) << KVM_REG_ARM_COPROC_SHIFT) | \
((opc1) << KVM_REG_ARM_OPC1_SHIFT) | \
((crm) << KVM_REG_ARM_CRM_SHIFT))
#define REG_CORE32(kname) ( \
(KVM_REG_ARM | KVM_REG_SIZE_U32) | \
(KVM_REG_ARM_CORE) | \
(KVM_REG_ARM_CORE_REG(kname)))
#define REG_VFP32(regno) ( \
(KVM_REG_ARM | KVM_REG_SIZE_U32) | \
KVM_REG_ARM_VFP | (regno))
#define REG_VFP64(regno) ( \
(KVM_REG_ARM | KVM_REG_SIZE_U64) | \
KVM_REG_ARM_VFP | (regno))
#define REG_DEMUX32(dmxid, val) ( \
(KVM_REG_ARM | KVM_REG_SIZE_U32) | \
(dmxid) | (val))
// Some of the co-processor registers are invariants and must have the
// same value on both the host and the guest. We need to keep a list
// of these to prevent gem5 from fiddling with them on the guest.
static uint64_t invariant_reg_vector[] = {
REG_CP32(15, 0, 0, 0, 0), // MIDR
REG_CP32(15, 0, 0, 0, 1), // CTR
REG_CP32(15, 0, 0, 0, 2), // TCMTR
REG_CP32(15, 0, 0, 0, 3), // TLBTR
REG_CP32(15, 0, 0, 0, 6), // REVIDR
REG_CP32(15, 0, 0, 1, 0), // ID_PFR0
REG_CP32(15, 0, 0, 1, 1), // ID_PFR1
REG_CP32(15, 0, 0, 1, 2), // ID_DFR0
REG_CP32(15, 0, 0, 1, 3), // ID_AFR0
REG_CP32(15, 0, 0, 1, 4), // ID_MMFR0
REG_CP32(15, 0, 0, 1, 5), // ID_MMFR1
REG_CP32(15, 0, 0, 1, 6), // ID_MMFR2
REG_CP32(15, 0, 0, 1, 7), // ID_MMFR3
REG_CP32(15, 0, 0, 2, 0), // ID_ISAR0
REG_CP32(15, 0, 0, 2, 1), // ID_ISAR1
REG_CP32(15, 0, 0, 2, 2), // ID_ISAR2
REG_CP32(15, 0, 0, 2, 3), // ID_ISAR3
REG_CP32(15, 0, 0, 2, 4), // ID_ISAR4
REG_CP32(15, 0, 0, 2, 5), // ID_ISAR5
REG_CP32(15, 0, 1, 0, 0), // CSSIDR
REG_CP32(15, 0, 1, 0, 1), // CLIDR
REG_CP32(15, 0, 1, 0, 7), // AIDR
REG_VFP32(KVM_REG_ARM_VFP_MVFR0),
REG_VFP32(KVM_REG_ARM_VFP_MVFR1),
REG_VFP32(KVM_REG_ARM_VFP_FPSID),
REG_DEMUX32(KVM_REG_ARM_DEMUX_ID_CCSIDR, 0),
};
const static uint64_t KVM_REG64_TTBR0(REG_CP64(15, 0, 2));
const static uint64_t KVM_REG64_TTBR1(REG_CP64(15, 1, 2));
#define INTERRUPT_ID(type, vcpu, irq) ( \
((type) << KVM_ARM_IRQ_TYPE_SHIFT) | \
((vcpu) << KVM_ARM_IRQ_VCPU_SHIFT) | \
((irq) << KVM_ARM_IRQ_NUM_SHIFT))
#define INTERRUPT_VCPU_IRQ(vcpu) \
INTERRUPT_ID(KVM_ARM_IRQ_TYPE_CPU, vcpu, KVM_ARM_IRQ_CPU_IRQ)
#define INTERRUPT_VCPU_FIQ(vcpu) \
INTERRUPT_ID(KVM_ARM_IRQ_TYPE_CPU, vcpu, KVM_ARM_IRQ_CPU_FIQ)
#define COUNT_OF(l) (sizeof(l) / sizeof(*l))
const std::set<uint64_t> ArmKvmCPU::invariant_regs(
invariant_reg_vector,
invariant_reg_vector + COUNT_OF(invariant_reg_vector));
ArmKvmCPU::KvmIntRegInfo ArmKvmCPU::kvmIntRegs[] = {
{ REG_CORE32(usr_regs.ARM_r0), INTREG_R0, "R0" },
{ REG_CORE32(usr_regs.ARM_r1), INTREG_R1, "R1" },
{ REG_CORE32(usr_regs.ARM_r2), INTREG_R2, "R2" },
{ REG_CORE32(usr_regs.ARM_r3), INTREG_R3, "R3" },
{ REG_CORE32(usr_regs.ARM_r4), INTREG_R4, "R4" },
{ REG_CORE32(usr_regs.ARM_r5), INTREG_R5, "R5" },
{ REG_CORE32(usr_regs.ARM_r6), INTREG_R6, "R6" },
{ REG_CORE32(usr_regs.ARM_r7), INTREG_R7, "R7" },
{ REG_CORE32(usr_regs.ARM_r8), INTREG_R8, "R8" },
{ REG_CORE32(usr_regs.ARM_r9), INTREG_R9, "R9" },
{ REG_CORE32(usr_regs.ARM_r10), INTREG_R10, "R10" },
{ REG_CORE32(usr_regs.ARM_fp), INTREG_R11, "R11" },
{ REG_CORE32(usr_regs.ARM_ip), INTREG_R12, "R12" },
{ REG_CORE32(usr_regs.ARM_sp), INTREG_R13, "R13(USR)" },
{ REG_CORE32(usr_regs.ARM_lr), INTREG_R14, "R14(USR)" },
{ REG_CORE32(svc_regs[0]), INTREG_SP_SVC, "R13(SVC)" },
{ REG_CORE32(svc_regs[1]), INTREG_LR_SVC, "R14(SVC)" },
{ REG_CORE32(abt_regs[0]), INTREG_SP_ABT, "R13(ABT)" },
{ REG_CORE32(abt_regs[1]), INTREG_LR_ABT, "R14(ABT)" },
{ REG_CORE32(und_regs[0]), INTREG_SP_UND, "R13(UND)" },
{ REG_CORE32(und_regs[1]), INTREG_LR_UND, "R14(UND)" },
{ REG_CORE32(irq_regs[0]), INTREG_SP_IRQ, "R13(IRQ)" },
{ REG_CORE32(irq_regs[1]), INTREG_LR_IRQ, "R14(IRQ)" },
{ REG_CORE32(fiq_regs[0]), INTREG_R8_FIQ, "R8(FIQ)" },
{ REG_CORE32(fiq_regs[1]), INTREG_R9_FIQ, "R9(FIQ)" },
{ REG_CORE32(fiq_regs[2]), INTREG_R10_FIQ, "R10(FIQ)" },
{ REG_CORE32(fiq_regs[3]), INTREG_R11_FIQ, "R11(FIQ)" },
{ REG_CORE32(fiq_regs[4]), INTREG_R12_FIQ, "R12(FIQ)" },
{ REG_CORE32(fiq_regs[5]), INTREG_R13_FIQ, "R13(FIQ)" },
{ REG_CORE32(fiq_regs[6]), INTREG_R14_FIQ, "R14(FIQ)" },
{ 0, NUM_INTREGS, NULL }
};
ArmKvmCPU::KvmCoreMiscRegInfo ArmKvmCPU::kvmCoreMiscRegs[] = {
{ REG_CORE32(usr_regs.ARM_cpsr), MISCREG_CPSR, "CPSR" },
{ REG_CORE32(svc_regs[2]), MISCREG_SPSR_SVC, "SPSR(SVC)" },
{ REG_CORE32(abt_regs[2]), MISCREG_SPSR_ABT, "SPSR(ABT)" },
{ REG_CORE32(und_regs[2]), MISCREG_SPSR_UND, "SPSR(UND)" },
{ REG_CORE32(irq_regs[2]), MISCREG_SPSR_IRQ, "SPSR(IRQ)" },
{ REG_CORE32(fiq_regs[2]), MISCREG_SPSR_FIQ, "SPSR(FIQ)" },
{ 0, NUM_MISCREGS }
};
ArmKvmCPU::ArmKvmCPU(ArmKvmCPUParams *params)
: BaseKvmCPU(params),
irqAsserted(false), fiqAsserted(false)
{
}
ArmKvmCPU::~ArmKvmCPU()
{
}
void
ArmKvmCPU::startup()
{
BaseKvmCPU::startup();
/* TODO: This needs to be moved when we start to support VMs with
* multiple threads since kvmArmVCpuInit requires that all CPUs in
* the VM have been created.
*/
/* TODO: The CPU type needs to be configurable once KVM on ARM
* starts to support more CPUs.
*/
kvmArmVCpuInit(KVM_ARM_TARGET_CORTEX_A15);
}
void
ArmKvmCPU::tick()
{
bool simFIQ(interrupts->checkRaw(INT_FIQ));
bool simIRQ(interrupts->checkRaw(INT_IRQ));
if (fiqAsserted != simFIQ) {
fiqAsserted = simFIQ;
DPRINTF(KvmInt, "KVM: Update FIQ state: %i\n", simFIQ);
vm.setIRQLine(INTERRUPT_VCPU_FIQ(vcpuID), simFIQ);
}
if (irqAsserted != simIRQ) {
irqAsserted = simIRQ;
DPRINTF(KvmInt, "KVM: Update IRQ state: %i\n", simIRQ);
vm.setIRQLine(INTERRUPT_VCPU_IRQ(vcpuID), simIRQ);
}
BaseKvmCPU::tick();
}
void
ArmKvmCPU::updateKvmState()
{
DPRINTF(KvmContext, "Updating KVM state...\n");
updateKvmStateCore();
updateKvmStateMisc();
}
void
ArmKvmCPU::updateThreadContext()
{
DPRINTF(KvmContext, "Updating gem5 state...\n");
updateTCStateCore();
updateTCStateMisc();
}
const ArmKvmCPU::RegIndexVector &
ArmKvmCPU::getRegList() const
{
if (_regIndexList.size() == 0) {
std::unique_ptr<struct kvm_reg_list> regs;
uint64_t i(1);
do {
i <<= 1;
regs.reset((struct kvm_reg_list *)
operator new(sizeof(struct kvm_reg_list) +
i * sizeof(uint64_t)));
regs->n = i;
} while (!getRegList(*regs));
_regIndexList.assign(regs->reg,
regs->reg + regs->n);
}
return _regIndexList;
}
void
ArmKvmCPU::kvmArmVCpuInit(uint32_t target)
{
struct kvm_vcpu_init init;
memset(&init, 0, sizeof(init));
init.target = target;
kvmArmVCpuInit(init);
}
void
ArmKvmCPU::kvmArmVCpuInit(const struct kvm_vcpu_init &init)
{
if (ioctl(KVM_ARM_VCPU_INIT, (void *)&init) == -1)
panic("KVM: Failed to initialize vCPU\n");
}
MiscRegIndex
ArmKvmCPU::decodeCoProcReg(uint64_t id) const
{
const unsigned cp(REG_CP(id));
const bool is_reg32(REG_IS_32BIT(id));
const bool is_reg64(REG_IS_64BIT(id));
// CP numbers larger than 15 are reserved for KVM extensions
if (cp > 15)
return NUM_MISCREGS;
const unsigned crm(REG_CRM(id));
const unsigned crn(REG_CRN(id));
const unsigned opc1(REG_OPC1(id));
const unsigned opc2(REG_OPC2(id));
if (is_reg32) {
switch (cp) {
case 14:
return decodeCP14Reg(crn, opc1, crm, opc2);
case 15:
return decodeCP15Reg(crn, opc1, crm, opc2);
default:
return NUM_MISCREGS;
}
} else if(is_reg64) {
return NUM_MISCREGS;
} else {
warn("Unhandled register length, register (0x%x) ignored.\n");
return NUM_MISCREGS;
}
}
ArmISA::MiscRegIndex
ArmKvmCPU::decodeVFPCtrlReg(uint64_t id) const
{
if (!REG_IS_ARM(id) || !REG_IS_VFP(id) || !REG_IS_VFP_CTRL(id))
return NUM_MISCREGS;
const unsigned vfp_reg(REG_VFP_REG(id));
switch (vfp_reg) {
case KVM_REG_ARM_VFP_FPSID: return MISCREG_FPSID;
case KVM_REG_ARM_VFP_FPSCR: return MISCREG_FPSCR;
case KVM_REG_ARM_VFP_MVFR0: return MISCREG_MVFR0;
case KVM_REG_ARM_VFP_MVFR1: return MISCREG_MVFR1;
case KVM_REG_ARM_VFP_FPEXC: return MISCREG_FPEXC;
case KVM_REG_ARM_VFP_FPINST:
case KVM_REG_ARM_VFP_FPINST2:
warn_once("KVM: FPINST not implemented.\n");
return NUM_MISCREGS;
default:
return NUM_MISCREGS;
}
}
bool
ArmKvmCPU::isInvariantReg(uint64_t id)
{
/* Mask away the value field from multiplexed registers, we assume
* that entire groups of multiplexed registers can be treated as
* invariant. */
if (REG_IS_ARM(id) && REG_IS_DEMUX(id))
id &= ~KVM_REG_ARM_DEMUX_VAL_MASK;
return invariant_regs.find(id) != invariant_regs.end();
}
bool
ArmKvmCPU::getRegList(struct kvm_reg_list &regs) const
{
if (ioctl(KVM_GET_REG_LIST, (void *)&regs) == -1) {
if (errno == E2BIG) {
return false;
} else {
panic("KVM: Failed to get vCPU register list (errno: %i)\n",
errno);
}
} else {
return true;
}
}
void
ArmKvmCPU::updateKvmStateCore()
{
for (const KvmIntRegInfo *ri(kvmIntRegs);
ri->idx != NUM_INTREGS; ++ri) {
uint64_t value(tc->readIntRegFlat(ri->idx));
DPRINTF(KvmContext, "kvm(%s) := 0x%x\n", ri->name, value);
setOneReg(ri->id, value);
}
DPRINTF(KvmContext, "kvm(PC) := 0x%x\n", tc->instAddr());
setOneReg(REG_CORE32(usr_regs.ARM_pc), tc->instAddr());
for (const KvmCoreMiscRegInfo *ri(kvmCoreMiscRegs);
ri->idx != NUM_MISCREGS; ++ri) {
uint64_t value(tc->readMiscReg(ri->idx));
DPRINTF(KvmContext, "kvm(%s) := 0x%x\n", ri->name, value);
setOneReg(ri->id, value);
}
}
void
ArmKvmCPU::updateKvmStateMisc()
{
static bool warned(false); // We can't use warn_once since we want
// to show /all/ registers
const RegIndexVector &regs(getRegList());
for (RegIndexVector::const_iterator it(regs.begin());
it != regs.end();
++it) {
if (!REG_IS_ARM(*it)) {
if (!warned)
warn("Skipping non-ARM register: 0x%x\n", *it);
} else if (isInvariantReg(*it)) {
DPRINTF(Kvm, "Skipping invariant register: 0x%x\n", *it);
} else if (REG_IS_CORE(*it)) {
// Core registers are handled in updateKvmStateCore
continue;
} else if (REG_CP(*it) <= 15) {
updateKvmStateCoProc(*it, !warned);
} else if (REG_IS_VFP(*it)) {
updateKvmStateVFP(*it, !warned);
} else {
if (!warned) {
warn("Skipping register with unknown CP (%i) id: 0x%x\n",
REG_CP(*it), *it);
}
}
}
warned = true;
}
void
ArmKvmCPU::updateKvmStateCoProc(uint64_t id, bool show_warnings)
{
MiscRegIndex reg(decodeCoProcReg(id));
assert(REG_IS_ARM(id));
assert(REG_CP(id) <= 15);
if (id == KVM_REG64_TTBR0 || id == KVM_REG64_TTBR1) {
// HACK HACK HACK: Workaround for 64-bit TTBRx
reg = (id == KVM_REG64_TTBR0 ? MISCREG_TTBR0 : MISCREG_TTBR1);
if (show_warnings)
hack("KVM: 64-bit TTBBRx workaround\n");
}
if (reg == NUM_MISCREGS) {
if (show_warnings) {
warn("KVM: Ignoring unknown KVM co-processor register (0x%.8x):\n",
id);
warn("\t0x%x: [CP: %i 64: %i CRn: c%i opc1: %.2i CRm: c%i"
" opc2: %i]\n",
id, REG_CP(id), REG_IS_64BIT(id), REG_CRN(id),
REG_OPC1(id), REG_CRM(id), REG_OPC2(id));
}
} else if (reg >= MISCREG_CP15_UNIMP_START && reg < MISCREG_CP15_END) {
if (show_warnings)
warn("KVM: Co-processor reg. %s not implemented by gem5.\n",
miscRegName[reg]);
} else {
setOneReg(id, tc->readMiscRegNoEffect(reg));
}
}
void
ArmKvmCPU::updateKvmStateVFP(uint64_t id, bool show_warnings)
{
assert(REG_IS_ARM(id));
assert(REG_IS_VFP(id));
if (REG_IS_VFP_REG(id)) {
if (!REG_IS_64BIT(id)) {
if (show_warnings)
warn("Unexpected VFP register length (reg: 0x%x).\n", id);
return;
}
const unsigned idx(id & KVM_REG_ARM_VFP_MASK);
const unsigned idx_base(idx << 1);
const unsigned idx_hi(idx_base + 1);
const unsigned idx_lo(idx_base + 0);
uint64_t value(
((uint64_t)tc->readFloatRegBitsFlat(idx_hi) << 32) |
tc->readFloatRegBitsFlat(idx_lo));
setOneReg(id, value);
} else if (REG_IS_VFP_CTRL(id)) {
MiscRegIndex idx(decodeVFPCtrlReg(id));
if (idx == NUM_MISCREGS) {
if (show_warnings)
warn("Unhandled VFP control register: 0x%x\n", id);
return;
}
if (!REG_IS_32BIT(id)) {
if (show_warnings)
warn("Ignoring VFP control register (%s) with "
"unexpected size.\n",
miscRegName[idx]);
return;
}
setOneReg(id, (uint32_t)tc->readMiscReg(idx));
} else {
if (show_warnings)
warn("Unhandled VFP register: 0x%x\n", id);
}
}
void
ArmKvmCPU::updateTCStateCore()
{
for (const KvmIntRegInfo *ri(kvmIntRegs);
ri->idx != NUM_INTREGS; ++ri) {
tc->setIntRegFlat(ri->idx, getOneRegU32(ri->id));
}
for (const KvmCoreMiscRegInfo *ri(kvmCoreMiscRegs);
ri->idx != NUM_MISCREGS; ++ri) {
tc->setMiscRegNoEffect(ri->idx, getOneRegU32(ri->id));
}
/* We want the simulator to execute all side-effects of the CPSR
* update since this updates PC state and register maps.
*/
tc->setMiscReg(MISCREG_CPSR, tc->readMiscRegNoEffect(MISCREG_CPSR));
// We update the PC state after we have updated the CPSR the
// contents of the CPSR affects how the npc is updated.
PCState pc(tc->pcState());
pc.set(getOneRegU32(REG_CORE32(usr_regs.ARM_pc)));
tc->pcState(pc);
}
void
ArmKvmCPU::updateTCStateMisc()
{
static bool warned(false); // We can't use warn_once since we want
// to show /all/ registers
const RegIndexVector &reg_ids(getRegList());;
for (RegIndexVector::const_iterator it(reg_ids.begin());
it != reg_ids.end(); ++it) {
if (!REG_IS_ARM(*it)) {
if (!warned)
warn("Skipping non-ARM register: 0x%x\n", *it);
} else if (REG_IS_CORE(*it)) {
// Core registers are handled in updateKvmStateCore
} else if (REG_CP(*it) <= 15) {
updateTCStateCoProc(*it, !warned);
} else if (REG_IS_VFP(*it)) {
updateTCStateVFP(*it, !warned);
} else {
if (!warned) {
warn("Skipping register with unknown CP (%i) id: 0x%x\n",
REG_CP(*it), *it);
}
}
}
warned = true;
}
void
ArmKvmCPU::updateTCStateCoProc(uint64_t id, bool show_warnings)
{
MiscRegIndex reg(decodeCoProcReg(id));
assert(REG_IS_ARM(id));
assert(REG_CP(id) <= 15);
if (id == KVM_REG64_TTBR0 || id == KVM_REG64_TTBR1) {
// HACK HACK HACK: We don't currently support 64-bit TTBR0/TTBR1
hack_once("KVM: 64-bit TTBRx workaround\n");
tc->setMiscRegNoEffect(
id == KVM_REG64_TTBR0 ? MISCREG_TTBR0 : MISCREG_TTBR1,
(uint32_t)(getOneRegU64(id) & 0xFFFFFFFF));
} else if (reg == MISCREG_TTBCR) {
uint32_t value(getOneRegU64(id));
if (value & 0x80000000)
panic("KVM: Guest tried to enable LPAE.\n");
tc->setMiscRegNoEffect(reg, value);
} else if (reg == NUM_MISCREGS) {
if (show_warnings) {
warn("KVM: Ignoring unknown KVM co-processor register:\n", id);
warn("\t0x%x: [CP: %i 64: %i CRn: c%i opc1: %.2i CRm: c%i"
" opc2: %i]\n",
id, REG_CP(id), REG_IS_64BIT(id), REG_CRN(id),
REG_OPC1(id), REG_CRM(id), REG_OPC2(id));
}
} else if (reg >= MISCREG_CP15_UNIMP_START && reg < MISCREG_CP15_END) {
if (show_warnings)
warn_once("KVM: Co-processor reg. %s not implemented by gem5.\n",
miscRegName[reg]);
} else {
tc->setMiscRegNoEffect(reg, getOneRegU32(id));
}
}
void
ArmKvmCPU::updateTCStateVFP(uint64_t id, bool show_warnings)
{
assert(REG_IS_ARM(id));
assert(REG_IS_VFP(id));
if (REG_IS_VFP_REG(id)) {
if (!REG_IS_64BIT(id)) {
if (show_warnings)
warn("Unexpected VFP register length (reg: 0x%x).\n", id);
return;
}
const unsigned idx(id & KVM_REG_ARM_VFP_MASK);
const unsigned idx_base(idx << 1);
const unsigned idx_hi(idx_base + 1);
const unsigned idx_lo(idx_base + 0);
uint64_t value(getOneRegU64(id));
tc->setFloatRegBitsFlat(idx_hi, (value >> 32) & 0xFFFFFFFF);
tc->setFloatRegBitsFlat(idx_lo, value & 0xFFFFFFFF);
} else if (REG_IS_VFP_CTRL(id)) {
MiscRegIndex idx(decodeVFPCtrlReg(id));
if (idx == NUM_MISCREGS) {
if (show_warnings)
warn("Unhandled VFP control register: 0x%x\n", id);
return;
}
if (!REG_IS_32BIT(id)) {
if (show_warnings)
warn("Ignoring VFP control register (%s) with "
"unexpected size.\n",
miscRegName[idx]);
return;
}
tc->setMiscReg(idx, getOneRegU64(id));
} else {
if (show_warnings)
warn("Unhandled VFP register: 0x%x\n", id);
}
}
ArmKvmCPU *
ArmKvmCPUParams::create()
{
return new ArmKvmCPU(this);
}

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/*
* Copyright (c) 2012 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: Andreas Sandberg
*/
#ifndef __CPU_KVM_ARM_CPU_HH__
#define __CPU_KVM_ARM_CPU_HH__
#include <set>
#include <vector>
#include "cpu/kvm/base.hh"
#include "params/ArmKvmCPU.hh"
/**
* ARM implementation of a KVM-based hardware virtualized CPU.
* Architecture specific limitations:
* * LPAE is currently not supported by gem5. We therefore panic if LPAE
* is enabled when returning to gem5.
* * The co-processor based interface to the architected timer is
* unsupported. We can't support this due to limitations in the KVM
* API on ARM.
* * M5 ops are currently not supported. This requires either a kernel
* hack or a memory mapped device that handles the guest<->m5
* interface.
*/
class ArmKvmCPU : public BaseKvmCPU
{
public:
ArmKvmCPU(ArmKvmCPUParams *params);
virtual ~ArmKvmCPU();
void startup();
protected:
struct KvmIntRegInfo {
/** KVM ID */
const uint64_t id;
/** gem5 index */
const IntRegIndex idx;
/** Name in debug output */
const char *name;
};
struct KvmCoreMiscRegInfo {
/** KVM ID */
const uint64_t id;
/** gem5 index */
const MiscRegIndex idx;
/** Name in debug output */
const char *name;
};
typedef std::vector<uint64_t> RegIndexVector;
void tick();
void updateKvmState();
void updateThreadContext();
/**
* Get a list of registers supported by getOneReg() and setOneReg().
*/
const RegIndexVector &getRegList() const;
void kvmArmVCpuInit(uint32_t target);
void kvmArmVCpuInit(const struct kvm_vcpu_init &init);
ArmISA::MiscRegIndex decodeCoProcReg(uint64_t id) const;
ArmISA::MiscRegIndex decodeVFPCtrlReg(uint64_t id) const;
/**
* Determine if a register is invariant.
*
* Some registers must have the same value in both the host and
* the guest. Such registers are referred to as "invariant"
* registers in KVM. This is a restriction imposed by KVM as
* having different values in ID registers (e.g., the cache
* identification registers) would confuse the guest kernel.
*/
bool isInvariantReg(uint64_t id);
static KvmIntRegInfo kvmIntRegs[];
static KvmCoreMiscRegInfo kvmCoreMiscRegs[];
private:
/**
* Get a list of registers supported by getOneReg() and setOneReg().
*
* @return False if the number of elements allocated in the list
* is too small to hold the complete register list (the required
* value is written into n in this case). True on success.
*/
bool getRegList(struct kvm_reg_list &regs) const;
void updateKvmStateCore();
void updateKvmStateMisc();
void updateKvmStateCoProc(uint64_t id, bool show_warnings);
void updateKvmStateVFP(uint64_t id, bool show_warnings);
void updateTCStateCore();
void updateTCStateMisc();
void updateTCStateCoProc(uint64_t id, bool show_warnings);
void updateTCStateVFP(uint64_t id, bool show_warnings);
/** Cached state of the IRQ line */
bool irqAsserted;
/** Cached state of the FIQ line */
bool fiqAsserted;
/**
* Cached copy of the list of co-processor registers supported by
* KVM
*/
mutable RegIndexVector _regIndexList;
/**
* List of co-processor registers that KVM requires to be
* identical on both the host and the guest. KVM does not allow
* writes to these registers.
*/
static const std::set<uint64_t> invariant_regs;
};
#endif