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qemu-e2k/target/riscv/op_helper.c

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RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
/*
* RISC-V Emulation Helpers for QEMU.
*
* Copyright (c) 2016-2017 Sagar Karandikar, sagark@eecs.berkeley.edu
* Copyright (c) 2017-2018 SiFive, Inc.
*
* 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 or later, 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 "qemu/osdep.h"
#include "qemu/log.h"
#include "cpu.h"
#include "qemu/main-loop.h"
#include "exec/exec-all.h"
#include "exec/helper-proto.h"
#ifndef CONFIG_USER_ONLY
#if defined(TARGET_RISCV32)
static const char valid_vm_1_09[16] = {
[VM_1_09_MBARE] = 1,
[VM_1_09_SV32] = 1,
};
static const char valid_vm_1_10[16] = {
[VM_1_10_MBARE] = 1,
[VM_1_10_SV32] = 1
};
#elif defined(TARGET_RISCV64)
static const char valid_vm_1_09[16] = {
[VM_1_09_MBARE] = 1,
[VM_1_09_SV39] = 1,
[VM_1_09_SV48] = 1,
};
static const char valid_vm_1_10[16] = {
[VM_1_10_MBARE] = 1,
[VM_1_10_SV39] = 1,
[VM_1_10_SV48] = 1,
[VM_1_10_SV57] = 1
};
#endif
static int validate_vm(CPURISCVState *env, target_ulong vm)
{
return (env->priv_ver >= PRIV_VERSION_1_10_0) ?
valid_vm_1_10[vm & 0xf] : valid_vm_1_09[vm & 0xf];
}
#endif
/* Exceptions processing helpers */
void QEMU_NORETURN do_raise_exception_err(CPURISCVState *env,
uint32_t exception, uintptr_t pc)
{
CPUState *cs = CPU(riscv_env_get_cpu(env));
qemu_log_mask(CPU_LOG_INT, "%s: %d\n", __func__, exception);
cs->exception_index = exception;
cpu_loop_exit_restore(cs, pc);
}
void helper_raise_exception(CPURISCVState *env, uint32_t exception)
{
do_raise_exception_err(env, exception, 0);
}
static void validate_mstatus_fs(CPURISCVState *env, uintptr_t ra)
{
#ifndef CONFIG_USER_ONLY
if (!(env->mstatus & MSTATUS_FS)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, ra);
}
#endif
}
/*
* Handle writes to CSRs and any resulting special behavior
*
* Adapted from Spike's processor_t::set_csr
*/
void csr_write_helper(CPURISCVState *env, target_ulong val_to_write,
target_ulong csrno)
{
#ifndef CONFIG_USER_ONLY
uint64_t delegable_ints = MIP_SSIP | MIP_STIP | MIP_SEIP | (1 << IRQ_X_COP);
uint64_t all_ints = delegable_ints | MIP_MSIP | MIP_MTIP;
#endif
switch (csrno) {
case CSR_FFLAGS:
validate_mstatus_fs(env, GETPC());
cpu_riscv_set_fflags(env, val_to_write & (FSR_AEXC >> FSR_AEXC_SHIFT));
break;
case CSR_FRM:
validate_mstatus_fs(env, GETPC());
env->frm = val_to_write & (FSR_RD >> FSR_RD_SHIFT);
break;
case CSR_FCSR:
validate_mstatus_fs(env, GETPC());
env->frm = (val_to_write & FSR_RD) >> FSR_RD_SHIFT;
cpu_riscv_set_fflags(env, (val_to_write & FSR_AEXC) >> FSR_AEXC_SHIFT);
break;
#ifndef CONFIG_USER_ONLY
case CSR_MSTATUS: {
target_ulong mstatus = env->mstatus;
target_ulong mask = 0;
target_ulong mpp = get_field(val_to_write, MSTATUS_MPP);
/* flush tlb on mstatus fields that affect VM */
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
if ((val_to_write ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPP |
MSTATUS_MPRV | MSTATUS_SUM | MSTATUS_VM)) {
helper_tlb_flush(env);
}
mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM |
MSTATUS_MPP | MSTATUS_MXR |
(validate_vm(env, get_field(val_to_write, MSTATUS_VM)) ?
MSTATUS_VM : 0);
}
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
if ((val_to_write ^ mstatus) & (MSTATUS_MXR | MSTATUS_MPP |
MSTATUS_MPRV | MSTATUS_SUM)) {
helper_tlb_flush(env);
}
mask = MSTATUS_SIE | MSTATUS_SPIE | MSTATUS_MIE | MSTATUS_MPIE |
MSTATUS_SPP | MSTATUS_FS | MSTATUS_MPRV | MSTATUS_SUM |
MSTATUS_MPP | MSTATUS_MXR;
}
/* silenty discard mstatus.mpp writes for unsupported modes */
if (mpp == PRV_H ||
(!riscv_has_ext(env, RVS) && mpp == PRV_S) ||
(!riscv_has_ext(env, RVU) && mpp == PRV_U)) {
mask &= ~MSTATUS_MPP;
}
mstatus = (mstatus & ~mask) | (val_to_write & mask);
RISC-V: Workaround for critical mstatus.FS bug This change is a workaround for a bug where mstatus.FS is not correctly reporting dirty after operations that modify floating point registers. This a critical bug or RISC-V in QEMU as it results in floating point register file corruption when running SMP Linux due to task migration and possibly uniprocessor Linux if more than one process is using the FPU. This workaround will return dirty if mstatus.FS is switched from off to initial or clean. According to the specification it is legal for an implementation to return only off, or dirty. Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Peter Maydell <peter.maydell@linaro.org> Cc: Alex Bennée <alex.bennee@linaro.org> Cc: Richard Henderson <richard.henderson@linaro.org> Cc: Philippe Mathieu-Daudé <f4bug@amsat.org> Tested-by: Richard W.M. Jones <rjones@redhat.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2018-03-24 00:49:07 +01:00
/* Note: this is a workaround for an issue where mstatus.FS
does not report dirty after floating point operations
that modify floating point state. This workaround is
technically compliant with the RISC-V Privileged
specification as it is legal to return only off, or dirty.
at the expense of extra floating point save/restore. */
/* FP is always dirty or off */
if (mstatus & MSTATUS_FS) {
mstatus |= MSTATUS_FS;
}
int dirty = ((mstatus & MSTATUS_FS) == MSTATUS_FS) |
((mstatus & MSTATUS_XS) == MSTATUS_XS);
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
mstatus = set_field(mstatus, MSTATUS_SD, dirty);
env->mstatus = mstatus;
break;
}
case CSR_MIP: {
/*
* Since the writeable bits in MIP are not set asynchrously by the
* CLINT, no additional locking is needed for read-modifiy-write
* CSR operations
*/
qemu_mutex_lock_iothread();
RISCVCPU *cpu = riscv_env_get_cpu(env);
riscv_set_local_interrupt(cpu, MIP_SSIP,
(val_to_write & MIP_SSIP) != 0);
riscv_set_local_interrupt(cpu, MIP_STIP,
(val_to_write & MIP_STIP) != 0);
/*
* csrs, csrc on mip.SEIP is not decomposable into separate read and
* write steps, so a different implementation is needed
*/
qemu_mutex_unlock_iothread();
break;
}
case CSR_MIE: {
env->mie = (env->mie & ~all_ints) |
(val_to_write & all_ints);
break;
}
case CSR_MIDELEG:
env->mideleg = (env->mideleg & ~delegable_ints)
| (val_to_write & delegable_ints);
break;
case CSR_MEDELEG: {
target_ulong mask = 0;
mask |= 1ULL << (RISCV_EXCP_INST_ADDR_MIS);
mask |= 1ULL << (RISCV_EXCP_INST_ACCESS_FAULT);
mask |= 1ULL << (RISCV_EXCP_ILLEGAL_INST);
mask |= 1ULL << (RISCV_EXCP_BREAKPOINT);
mask |= 1ULL << (RISCV_EXCP_LOAD_ADDR_MIS);
mask |= 1ULL << (RISCV_EXCP_LOAD_ACCESS_FAULT);
mask |= 1ULL << (RISCV_EXCP_STORE_AMO_ADDR_MIS);
mask |= 1ULL << (RISCV_EXCP_STORE_AMO_ACCESS_FAULT);
mask |= 1ULL << (RISCV_EXCP_U_ECALL);
mask |= 1ULL << (RISCV_EXCP_S_ECALL);
mask |= 1ULL << (RISCV_EXCP_H_ECALL);
mask |= 1ULL << (RISCV_EXCP_M_ECALL);
mask |= 1ULL << (RISCV_EXCP_INST_PAGE_FAULT);
mask |= 1ULL << (RISCV_EXCP_LOAD_PAGE_FAULT);
mask |= 1ULL << (RISCV_EXCP_STORE_PAGE_FAULT);
env->medeleg = (env->medeleg & ~mask)
| (val_to_write & mask);
break;
}
case CSR_MINSTRET:
RISC-V: No traps on writes to misa,minstret,mcycle These fields are marked WARL (Write Any Values, Reads Legal Values) in the RISC-V Privileged Architecture Specification so instead of raising exceptions, illegal writes are silently dropped. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-05 22:33:31 +01:00
/* minstret is WARL so unsupported writes are ignored */
break;
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MCYCLE:
RISC-V: No traps on writes to misa,minstret,mcycle These fields are marked WARL (Write Any Values, Reads Legal Values) in the RISC-V Privileged Architecture Specification so instead of raising exceptions, illegal writes are silently dropped. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-05 22:33:31 +01:00
/* mcycle is WARL so unsupported writes are ignored */
break;
#if defined(TARGET_RISCV32)
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MINSTRETH:
RISC-V: No traps on writes to misa,minstret,mcycle These fields are marked WARL (Write Any Values, Reads Legal Values) in the RISC-V Privileged Architecture Specification so instead of raising exceptions, illegal writes are silently dropped. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-05 22:33:31 +01:00
/* minstreth is WARL so unsupported writes are ignored */
break;
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MCYCLEH:
RISC-V: No traps on writes to misa,minstret,mcycle These fields are marked WARL (Write Any Values, Reads Legal Values) in the RISC-V Privileged Architecture Specification so instead of raising exceptions, illegal writes are silently dropped. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-05 22:33:31 +01:00
/* mcycleh is WARL so unsupported writes are ignored */
break;
#endif
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MUCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
env->scounteren = val_to_write;
break;
} else {
goto do_illegal;
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MSCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
env->mcounteren = val_to_write;
break;
} else {
goto do_illegal;
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_SSTATUS: {
target_ulong ms = env->mstatus;
target_ulong mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_UIE
| SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS
RISC-V: Allow S-mode mxr access when priv ISA >= v1.10 The mstatus.MXR alias in sstatus should only be writable by S-mode if the privileged ISA version >= v1.10. Also MXR was masked in sstatus CSR read but not sstatus CSR writes. Now we correctly mask sstatus.mxr in both read and write. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-09 02:06:30 +02:00
| SSTATUS_SUM | SSTATUS_SD;
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
mask |= SSTATUS_MXR;
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
ms = (ms & ~mask) | (val_to_write & mask);
csr_write_helper(env, ms, CSR_MSTATUS);
break;
}
case CSR_SIP: {
qemu_mutex_lock_iothread();
target_ulong next_mip = (env->mip & ~env->mideleg)
| (val_to_write & env->mideleg);
qemu_mutex_unlock_iothread();
csr_write_helper(env, next_mip, CSR_MIP);
break;
}
case CSR_SIE: {
target_ulong next_mie = (env->mie & ~env->mideleg)
| (val_to_write & env->mideleg);
csr_write_helper(env, next_mie, CSR_MIE);
break;
}
case CSR_SATP: /* CSR_SPTBR */ {
if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
RISC-V: Hardwire satp to 0 for no-mmu case satp is WARL so it should not trap on illegal writes, rather it can be hardwired to zero and silently ignore illegal writes. It seems the RISC-V WARL behaviour is preferred to having to trap overhead versus simply reading back the value and checking if the write took (saves hundreds of cycles and more complex trap handling code). Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-03-05 21:48:41 +01:00
break;
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
}
if (env->priv_ver <= PRIV_VERSION_1_09_1 && (val_to_write ^ env->sptbr))
{
helper_tlb_flush(env);
env->sptbr = val_to_write & (((target_ulong)
1 << (TARGET_PHYS_ADDR_SPACE_BITS - PGSHIFT)) - 1);
}
if (env->priv_ver >= PRIV_VERSION_1_10_0 &&
validate_vm(env, get_field(val_to_write, SATP_MODE)) &&
((val_to_write ^ env->satp) & (SATP_MODE | SATP_ASID | SATP_PPN)))
{
helper_tlb_flush(env);
env->satp = val_to_write;
}
break;
}
case CSR_SEPC:
env->sepc = val_to_write;
break;
case CSR_STVEC:
RISC-V: Make mtvec/stvec ignore vectored traps Vectored traps for asynchrounous interrupts are optional. The mtvec/stvec mode field is WARL and hence does not trap if an illegal value is written. Illegal values are ignored. Later we can add RISCV_FEATURE_VECTORED_TRAPS however until then the correct behavior for WARL (Write Any, Read Legal) fields is to drop writes to unsupported bits. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-05 22:17:11 +01:00
/* bits [1:0] encode mode; 0 = direct, 1 = vectored, 2 >= reserved */
if ((val_to_write & 3) == 0) {
env->stvec = val_to_write >> 2 << 2;
} else {
RISC-V: Add trailing '\n' to qemu_log() calls Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20180606152128.449-11-f4bug@amsat.org Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-08 14:15:33 +02:00
qemu_log_mask(LOG_UNIMP,
"CSR_STVEC: vectored traps not supported\n");
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
}
break;
case CSR_SCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
env->scounteren = val_to_write;
break;
} else {
goto do_illegal;
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_SSCRATCH:
env->sscratch = val_to_write;
break;
case CSR_SCAUSE:
env->scause = val_to_write;
break;
case CSR_SBADADDR:
env->sbadaddr = val_to_write;
break;
case CSR_MEPC:
env->mepc = val_to_write;
break;
case CSR_MTVEC:
RISC-V: Make mtvec/stvec ignore vectored traps Vectored traps for asynchrounous interrupts are optional. The mtvec/stvec mode field is WARL and hence does not trap if an illegal value is written. Illegal values are ignored. Later we can add RISCV_FEATURE_VECTORED_TRAPS however until then the correct behavior for WARL (Write Any, Read Legal) fields is to drop writes to unsupported bits. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-05 22:17:11 +01:00
/* bits [1:0] indicate mode; 0 = direct, 1 = vectored, 2 >= reserved */
if ((val_to_write & 3) == 0) {
env->mtvec = val_to_write >> 2 << 2;
} else {
RISC-V: Add trailing '\n' to qemu_log() calls Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org> Message-id: 20180606152128.449-11-f4bug@amsat.org Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2018-06-08 14:15:33 +02:00
qemu_log_mask(LOG_UNIMP,
"CSR_MTVEC: vectored traps not supported\n");
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
}
break;
case CSR_MCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
env->mcounteren = val_to_write;
break;
} else {
goto do_illegal;
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MSCRATCH:
env->mscratch = val_to_write;
break;
case CSR_MCAUSE:
env->mcause = val_to_write;
break;
case CSR_MBADADDR:
env->mbadaddr = val_to_write;
break;
RISC-V: No traps on writes to misa,minstret,mcycle These fields are marked WARL (Write Any Values, Reads Legal Values) in the RISC-V Privileged Architecture Specification so instead of raising exceptions, illegal writes are silently dropped. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-05 22:33:31 +01:00
case CSR_MISA:
/* misa is WARL so unsupported writes are ignored */
break;
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_PMPCFG0:
case CSR_PMPCFG1:
case CSR_PMPCFG2:
case CSR_PMPCFG3:
pmpcfg_csr_write(env, csrno - CSR_PMPCFG0, val_to_write);
break;
case CSR_PMPADDR0:
case CSR_PMPADDR1:
case CSR_PMPADDR2:
case CSR_PMPADDR3:
case CSR_PMPADDR4:
case CSR_PMPADDR5:
case CSR_PMPADDR6:
case CSR_PMPADDR7:
case CSR_PMPADDR8:
case CSR_PMPADDR9:
case CSR_PMPADDR10:
case CSR_PMPADDR11:
case CSR_PMPADDR12:
case CSR_PMPADDR13:
case CSR_PMPADDR14:
case CSR_PMPADDR15:
pmpaddr_csr_write(env, csrno - CSR_PMPADDR0, val_to_write);
break;
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
#endif
#if !defined(CONFIG_USER_ONLY)
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
do_illegal:
#endif
default:
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
}
/*
* Handle reads to CSRs and any resulting special behavior
*
* Adapted from Spike's processor_t::get_csr
*/
target_ulong csr_read_helper(CPURISCVState *env, target_ulong csrno)
{
#ifndef CONFIG_USER_ONLY
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
target_ulong ctr_en = env->priv == PRV_U ? env->scounteren :
env->priv == PRV_S ? env->mcounteren : -1U;
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
#else
target_ulong ctr_en = -1;
#endif
target_ulong ctr_ok = (ctr_en >> (csrno & 31)) & 1;
if (csrno >= CSR_HPMCOUNTER3 && csrno <= CSR_HPMCOUNTER31) {
if (ctr_ok) {
return 0;
}
}
#if defined(TARGET_RISCV32)
if (csrno >= CSR_HPMCOUNTER3H && csrno <= CSR_HPMCOUNTER31H) {
if (ctr_ok) {
return 0;
}
}
#endif
if (csrno >= CSR_MHPMCOUNTER3 && csrno <= CSR_MHPMCOUNTER31) {
return 0;
}
#if defined(TARGET_RISCV32)
if (csrno >= CSR_MHPMCOUNTER3 && csrno <= CSR_MHPMCOUNTER31) {
return 0;
}
#endif
if (csrno >= CSR_MHPMEVENT3 && csrno <= CSR_MHPMEVENT31) {
return 0;
}
switch (csrno) {
case CSR_FFLAGS:
validate_mstatus_fs(env, GETPC());
return cpu_riscv_get_fflags(env);
case CSR_FRM:
validate_mstatus_fs(env, GETPC());
return env->frm;
case CSR_FCSR:
validate_mstatus_fs(env, GETPC());
return (cpu_riscv_get_fflags(env) << FSR_AEXC_SHIFT)
| (env->frm << FSR_RD_SHIFT);
/* rdtime/rdtimeh is trapped and emulated by bbl in system mode */
#ifdef CONFIG_USER_ONLY
case CSR_TIME:
return cpu_get_host_ticks();
#if defined(TARGET_RISCV32)
case CSR_TIMEH:
return cpu_get_host_ticks() >> 32;
#endif
#endif
case CSR_INSTRET:
case CSR_CYCLE:
if (ctr_ok) {
RISC-V: Add mcycle/minstret support for -icount auto Previously the mycycle/minstret CSRs and rdcycle/rdinstret psuedo instructions would return the time as a proxy for an increasing instruction counter in the absence of having a precise instruction count. If QEMU is invoked with -icount, the mcycle/minstret CSRs and rdcycle/rdinstret psuedo instructions will return the instruction count. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-06 02:46:19 +02:00
#if !defined(CONFIG_USER_ONLY)
if (use_icount) {
return cpu_get_icount();
} else {
return cpu_get_host_ticks();
}
#else
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
return cpu_get_host_ticks();
RISC-V: Add mcycle/minstret support for -icount auto Previously the mycycle/minstret CSRs and rdcycle/rdinstret psuedo instructions would return the time as a proxy for an increasing instruction counter in the absence of having a precise instruction count. If QEMU is invoked with -icount, the mcycle/minstret CSRs and rdcycle/rdinstret psuedo instructions will return the instruction count. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-06 02:46:19 +02:00
#endif
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
}
break;
#if defined(TARGET_RISCV32)
case CSR_INSTRETH:
case CSR_CYCLEH:
if (ctr_ok) {
RISC-V: Add mcycle/minstret support for -icount auto Previously the mycycle/minstret CSRs and rdcycle/rdinstret psuedo instructions would return the time as a proxy for an increasing instruction counter in the absence of having a precise instruction count. If QEMU is invoked with -icount, the mcycle/minstret CSRs and rdcycle/rdinstret psuedo instructions will return the instruction count. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-06 02:46:19 +02:00
#if !defined(CONFIG_USER_ONLY)
if (use_icount) {
return cpu_get_icount() >> 32;
} else {
return cpu_get_host_ticks() >> 32;
}
#else
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
return cpu_get_host_ticks() >> 32;
RISC-V: Add mcycle/minstret support for -icount auto Previously the mycycle/minstret CSRs and rdcycle/rdinstret psuedo instructions would return the time as a proxy for an increasing instruction counter in the absence of having a precise instruction count. If QEMU is invoked with -icount, the mcycle/minstret CSRs and rdcycle/rdinstret psuedo instructions will return the instruction count. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-06 02:46:19 +02:00
#endif
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
}
break;
#endif
#ifndef CONFIG_USER_ONLY
case CSR_MINSTRET:
case CSR_MCYCLE:
RISC-V: Add mcycle/minstret support for -icount auto Previously the mycycle/minstret CSRs and rdcycle/rdinstret psuedo instructions would return the time as a proxy for an increasing instruction counter in the absence of having a precise instruction count. If QEMU is invoked with -icount, the mcycle/minstret CSRs and rdcycle/rdinstret psuedo instructions will return the instruction count. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-06 02:46:19 +02:00
if (use_icount) {
return cpu_get_icount();
} else {
return cpu_get_host_ticks();
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MINSTRETH:
case CSR_MCYCLEH:
#if defined(TARGET_RISCV32)
RISC-V: Add mcycle/minstret support for -icount auto Previously the mycycle/minstret CSRs and rdcycle/rdinstret psuedo instructions would return the time as a proxy for an increasing instruction counter in the absence of having a precise instruction count. If QEMU is invoked with -icount, the mcycle/minstret CSRs and rdcycle/rdinstret psuedo instructions will return the instruction count. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-06 02:46:19 +02:00
if (use_icount) {
return cpu_get_icount() >> 32;
} else {
return cpu_get_host_ticks() >> 32;
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
#endif
break;
case CSR_MUCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
return env->scounteren;
} else {
break; /* illegal instruction */
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MSCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver <= PRIV_VERSION_1_09_1) {
return env->mcounteren;
} else {
break; /* illegal instruction */
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_SSTATUS: {
target_ulong mask = SSTATUS_SIE | SSTATUS_SPIE | SSTATUS_UIE
| SSTATUS_UPIE | SSTATUS_SPP | SSTATUS_FS | SSTATUS_XS
RISC-V: Allow S-mode mxr access when priv ISA >= v1.10 The mstatus.MXR alias in sstatus should only be writable by S-mode if the privileged ISA version >= v1.10. Also MXR was masked in sstatus CSR read but not sstatus CSR writes. Now we correctly mask sstatus.mxr in both read and write. Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-04-09 02:06:30 +02:00
| SSTATUS_SUM | SSTATUS_SD;
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
mask |= SSTATUS_MXR;
}
return env->mstatus & mask;
}
case CSR_SIP: {
qemu_mutex_lock_iothread();
target_ulong tmp = env->mip & env->mideleg;
qemu_mutex_unlock_iothread();
return tmp;
}
case CSR_SIE:
return env->mie & env->mideleg;
case CSR_SEPC:
return env->sepc;
case CSR_SBADADDR:
return env->sbadaddr;
case CSR_STVEC:
return env->stvec;
case CSR_SCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
return env->scounteren;
} else {
break; /* illegal instruction */
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_SCAUSE:
return env->scause;
RISC-V: Hardwire satp to 0 for no-mmu case satp is WARL so it should not trap on illegal writes, rather it can be hardwired to zero and silently ignore illegal writes. It seems the RISC-V WARL behaviour is preferred to having to trap overhead versus simply reading back the value and checking if the write took (saves hundreds of cycles and more complex trap handling code). Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com> Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
2018-03-05 21:48:41 +01:00
case CSR_SATP: /* CSR_SPTBR */
if (!riscv_feature(env, RISCV_FEATURE_MMU)) {
return 0;
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
return env->satp;
} else {
return env->sptbr;
}
case CSR_SSCRATCH:
return env->sscratch;
case CSR_MSTATUS:
return env->mstatus;
case CSR_MIP: {
qemu_mutex_lock_iothread();
target_ulong tmp = env->mip;
qemu_mutex_unlock_iothread();
return tmp;
}
case CSR_MIE:
return env->mie;
case CSR_MEPC:
return env->mepc;
case CSR_MSCRATCH:
return env->mscratch;
case CSR_MCAUSE:
return env->mcause;
case CSR_MBADADDR:
return env->mbadaddr;
case CSR_MISA:
return env->misa;
case CSR_MARCHID:
return 0; /* as spike does */
case CSR_MIMPID:
return 0; /* as spike does */
case CSR_MVENDORID:
return 0; /* as spike does */
case CSR_MHARTID:
return env->mhartid;
case CSR_MTVEC:
return env->mtvec;
case CSR_MCOUNTEREN:
RISC-V: Use [ms]counteren CSRs when priv ISA >= v1.10 Privileged ISA v1.9.1 defines mscounteren and mucounteren: * mscounteren contains a mask of counters available to S-mode * mucounteren contains a mask of counters available to U-mode Privileged ISA v1.10 defines mcounteren and scounteren: * mcounteren contains a mask of counters available to S-mode * scounteren contains a mask of counters available to U-mode mcounteren and scounteren CSR registers were implemented however they were not honoured for counter accesses when the privilege ISA was >= v1.10. This fix solves the issue by coalescing the counter enable registers. In addition the code now generates illegal instruction exceptions for accesses to the counter enabled registers depending on the privileged ISA version. - Coalesce mscounteren and mcounteren into one variable - Coalesce mucounteren and scounteren into one variable - Makes mcounteren and scounteren CSR accesses generate illegal instructions when the privileged ISA <= v1.9.1 - Makes mscounteren and mucounteren CSR accesses generate illegal instructions when the privileged ISA >= v1.10 Cc: Sagar Karandikar <sagark@eecs.berkeley.edu> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de> Cc: Palmer Dabbelt <palmer@sifive.com> Cc: Alistair Francis <Alistair.Francis@wdc.com> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-04-09 01:33:05 +02:00
if (env->priv_ver >= PRIV_VERSION_1_10_0) {
return env->mcounteren;
} else {
break; /* illegal instruction */
}
RISC-V CPU Helpers Privileged control and status register helpers and page fault handling. Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Sagar Karandikar <sagark@eecs.berkeley.edu> Signed-off-by: Michael Clark <mjc@sifive.com>
2018-03-02 13:31:10 +01:00
case CSR_MEDELEG:
return env->medeleg;
case CSR_MIDELEG:
return env->mideleg;
case CSR_PMPCFG0:
case CSR_PMPCFG1:
case CSR_PMPCFG2:
case CSR_PMPCFG3:
return pmpcfg_csr_read(env, csrno - CSR_PMPCFG0);
case CSR_PMPADDR0:
case CSR_PMPADDR1:
case CSR_PMPADDR2:
case CSR_PMPADDR3:
case CSR_PMPADDR4:
case CSR_PMPADDR5:
case CSR_PMPADDR6:
case CSR_PMPADDR7:
case CSR_PMPADDR8:
case CSR_PMPADDR9:
case CSR_PMPADDR10:
case CSR_PMPADDR11:
case CSR_PMPADDR12:
case CSR_PMPADDR13:
case CSR_PMPADDR14:
case CSR_PMPADDR15:
return pmpaddr_csr_read(env, csrno - CSR_PMPADDR0);
#endif
}
/* used by e.g. MTIME read */
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
/*
* Check that CSR access is allowed.
*
* Adapted from Spike's decode.h:validate_csr
*/
static void validate_csr(CPURISCVState *env, uint64_t which,
uint64_t write, uintptr_t ra)
{
#ifndef CONFIG_USER_ONLY
unsigned csr_priv = get_field((which), 0x300);
unsigned csr_read_only = get_field((which), 0xC00) == 3;
if (((write) && csr_read_only) || (env->priv < csr_priv)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, ra);
}
#endif
}
target_ulong helper_csrrw(CPURISCVState *env, target_ulong src,
target_ulong csr)
{
validate_csr(env, csr, 1, GETPC());
uint64_t csr_backup = csr_read_helper(env, csr);
csr_write_helper(env, src, csr);
return csr_backup;
}
target_ulong helper_csrrs(CPURISCVState *env, target_ulong src,
target_ulong csr, target_ulong rs1_pass)
{
validate_csr(env, csr, rs1_pass != 0, GETPC());
uint64_t csr_backup = csr_read_helper(env, csr);
if (rs1_pass != 0) {
csr_write_helper(env, src | csr_backup, csr);
}
return csr_backup;
}
target_ulong helper_csrrc(CPURISCVState *env, target_ulong src,
target_ulong csr, target_ulong rs1_pass)
{
validate_csr(env, csr, rs1_pass != 0, GETPC());
uint64_t csr_backup = csr_read_helper(env, csr);
if (rs1_pass != 0) {
csr_write_helper(env, (~src) & csr_backup, csr);
}
return csr_backup;
}
#ifndef CONFIG_USER_ONLY
/* iothread_mutex must be held */
void riscv_set_local_interrupt(RISCVCPU *cpu, target_ulong mask, int value)
{
target_ulong old_mip = cpu->env.mip;
cpu->env.mip = (old_mip & ~mask) | (value ? mask : 0);
if (cpu->env.mip && !old_mip) {
cpu_interrupt(CPU(cpu), CPU_INTERRUPT_HARD);
} else if (!cpu->env.mip && old_mip) {
cpu_reset_interrupt(CPU(cpu), CPU_INTERRUPT_HARD);
}
}
void riscv_set_mode(CPURISCVState *env, target_ulong newpriv)
{
if (newpriv > PRV_M) {
g_assert_not_reached();
}
if (newpriv == PRV_H) {
newpriv = PRV_U;
}
/* tlb_flush is unnecessary as mode is contained in mmu_idx */
env->priv = newpriv;
}
target_ulong helper_sret(CPURISCVState *env, target_ulong cpu_pc_deb)
{
if (!(env->priv >= PRV_S)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
target_ulong retpc = env->sepc;
if (!riscv_has_ext(env, RVC) && (retpc & 0x3)) {
do_raise_exception_err(env, RISCV_EXCP_INST_ADDR_MIS, GETPC());
}
target_ulong mstatus = env->mstatus;
target_ulong prev_priv = get_field(mstatus, MSTATUS_SPP);
mstatus = set_field(mstatus,
env->priv_ver >= PRIV_VERSION_1_10_0 ?
MSTATUS_SIE : MSTATUS_UIE << prev_priv,
get_field(mstatus, MSTATUS_SPIE));
mstatus = set_field(mstatus, MSTATUS_SPIE, 0);
mstatus = set_field(mstatus, MSTATUS_SPP, PRV_U);
riscv_set_mode(env, prev_priv);
csr_write_helper(env, mstatus, CSR_MSTATUS);
return retpc;
}
target_ulong helper_mret(CPURISCVState *env, target_ulong cpu_pc_deb)
{
if (!(env->priv >= PRV_M)) {
do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC());
}
target_ulong retpc = env->mepc;
if (!riscv_has_ext(env, RVC) && (retpc & 0x3)) {
do_raise_exception_err(env, RISCV_EXCP_INST_ADDR_MIS, GETPC());
}
target_ulong mstatus = env->mstatus;
target_ulong prev_priv = get_field(mstatus, MSTATUS_MPP);
mstatus = set_field(mstatus,
env->priv_ver >= PRIV_VERSION_1_10_0 ?
MSTATUS_MIE : MSTATUS_UIE << prev_priv,
get_field(mstatus, MSTATUS_MPIE));
mstatus = set_field(mstatus, MSTATUS_MPIE, 0);
mstatus = set_field(mstatus, MSTATUS_MPP, PRV_U);
riscv_set_mode(env, prev_priv);
csr_write_helper(env, mstatus, CSR_MSTATUS);
return retpc;
}
void helper_wfi(CPURISCVState *env)
{
CPUState *cs = CPU(riscv_env_get_cpu(env));
cs->halted = 1;
cs->exception_index = EXCP_HLT;
cpu_loop_exit(cs);
}
void helper_tlb_flush(CPURISCVState *env)
{
RISCVCPU *cpu = riscv_env_get_cpu(env);
CPUState *cs = CPU(cpu);
tlb_flush(cs);
}
#endif /* !CONFIG_USER_ONLY */
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