qemu/target/ppc/helper_regs.c
Richard Henderson 2df4fe7abe target/ppc: Disconnect hflags from MSR
Copying flags directly from msr has drawbacks: (1) msr bits
mean different things per cpu, (2) msr has 64 bits on 64 cpus
while tb->flags has only 32 bits.

Create a enum to define these bits.  Document the origin of each bit
and validate those bits that must match MSR.  This fixes the
truncation of env->hflags to tb->flags, because we no longer
have hflags bits set above bit 31.

Most of the code in ppc_tr_init_disas_context is moved over to
hreg_compute_hflags.  Some of it is simple extractions from msr,
some requires examining other cpu flags.  Anything that is moved
becomes a simple extract from hflags in ppc_tr_init_disas_context.

Several existing bugs are left in ppc_tr_init_disas_context, where
additional changes are required -- to be addressed in future patches.

Remove a broken #if 0 block.

Reported-by: Ivan Warren <ivan@vmfacility.fr>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20210323184340.619757-3-richard.henderson@linaro.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2021-05-04 11:41:24 +10:00

248 lines
7.4 KiB
C

/*
* PowerPC emulation special registers manipulation helpers for qemu.
*
* Copyright (c) 2003-2007 Jocelyn Mayer
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, see <http://www.gnu.org/licenses/>.
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "qemu/main-loop.h"
#include "exec/exec-all.h"
#include "sysemu/kvm.h"
#include "helper_regs.h"
/* Swap temporary saved registers with GPRs */
void hreg_swap_gpr_tgpr(CPUPPCState *env)
{
target_ulong tmp;
tmp = env->gpr[0];
env->gpr[0] = env->tgpr[0];
env->tgpr[0] = tmp;
tmp = env->gpr[1];
env->gpr[1] = env->tgpr[1];
env->tgpr[1] = tmp;
tmp = env->gpr[2];
env->gpr[2] = env->tgpr[2];
env->tgpr[2] = tmp;
tmp = env->gpr[3];
env->gpr[3] = env->tgpr[3];
env->tgpr[3] = tmp;
}
void hreg_compute_mem_idx(CPUPPCState *env)
{
/*
* This is our encoding for server processors. The architecture
* specifies that there is no such thing as userspace with
* translation off, however it appears that MacOS does it and some
* 32-bit CPUs support it. Weird...
*
* 0 = Guest User space virtual mode
* 1 = Guest Kernel space virtual mode
* 2 = Guest User space real mode
* 3 = Guest Kernel space real mode
* 4 = HV User space virtual mode
* 5 = HV Kernel space virtual mode
* 6 = HV User space real mode
* 7 = HV Kernel space real mode
*
* For BookE, we need 8 MMU modes as follow:
*
* 0 = AS 0 HV User space
* 1 = AS 0 HV Kernel space
* 2 = AS 1 HV User space
* 3 = AS 1 HV Kernel space
* 4 = AS 0 Guest User space
* 5 = AS 0 Guest Kernel space
* 6 = AS 1 Guest User space
* 7 = AS 1 Guest Kernel space
*/
if (env->mmu_model & POWERPC_MMU_BOOKE) {
env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
env->immu_idx += msr_is ? 2 : 0;
env->dmmu_idx += msr_ds ? 2 : 0;
env->immu_idx += msr_gs ? 4 : 0;
env->dmmu_idx += msr_gs ? 4 : 0;
} else {
env->immu_idx = env->dmmu_idx = msr_pr ? 0 : 1;
env->immu_idx += msr_ir ? 0 : 2;
env->dmmu_idx += msr_dr ? 0 : 2;
env->immu_idx += msr_hv ? 4 : 0;
env->dmmu_idx += msr_hv ? 4 : 0;
}
}
void hreg_compute_hflags(CPUPPCState *env)
{
target_ulong msr = env->msr;
uint32_t ppc_flags = env->flags;
uint32_t hflags = 0;
uint32_t msr_mask;
/* Some bits come straight across from MSR. */
QEMU_BUILD_BUG_ON(MSR_LE != HFLAGS_LE);
QEMU_BUILD_BUG_ON(MSR_PR != HFLAGS_PR);
QEMU_BUILD_BUG_ON(MSR_DR != HFLAGS_DR);
QEMU_BUILD_BUG_ON(MSR_IR != HFLAGS_IR);
QEMU_BUILD_BUG_ON(MSR_FP != HFLAGS_FP);
QEMU_BUILD_BUG_ON(MSR_SA != HFLAGS_SA);
QEMU_BUILD_BUG_ON(MSR_AP != HFLAGS_AP);
msr_mask = ((1 << MSR_LE) | (1 << MSR_PR) |
(1 << MSR_DR) | (1 << MSR_IR) |
(1 << MSR_FP) | (1 << MSR_SA) | (1 << MSR_AP));
if (ppc_flags & POWERPC_FLAG_HID0_LE) {
/*
* Note that MSR_LE is not set in env->msr_mask for this cpu,
* and so will never be set in msr.
*/
uint32_t le = extract32(env->spr[SPR_HID0], 3, 1);
hflags |= le << MSR_LE;
}
if (ppc_flags & POWERPC_FLAG_BE) {
QEMU_BUILD_BUG_ON(MSR_BE != HFLAGS_BE);
msr_mask |= 1 << MSR_BE;
}
if (ppc_flags & POWERPC_FLAG_SE) {
QEMU_BUILD_BUG_ON(MSR_SE != HFLAGS_SE);
msr_mask |= 1 << MSR_SE;
}
if (msr_is_64bit(env, msr)) {
hflags |= 1 << HFLAGS_64;
}
if ((ppc_flags & POWERPC_FLAG_SPE) && (msr & (1 << MSR_SPE))) {
hflags |= 1 << HFLAGS_SPE;
}
if (ppc_flags & POWERPC_FLAG_VRE) {
QEMU_BUILD_BUG_ON(MSR_VR != HFLAGS_VR);
msr_mask |= 1 << MSR_VR;
}
if ((ppc_flags & POWERPC_FLAG_VSX) && (msr & (1 << MSR_VSX))) {
hflags |= 1 << HFLAGS_VSX;
}
if ((ppc_flags & POWERPC_FLAG_TM) && (msr & (1ull << MSR_TM))) {
hflags |= 1 << HFLAGS_TM;
}
#ifndef CONFIG_USER_ONLY
if (!env->has_hv_mode || (msr & (1ull << MSR_HV))) {
hflags |= 1 << HFLAGS_HV;
}
#endif
env->hflags = hflags | (msr & msr_mask);
hreg_compute_mem_idx(env);
}
void cpu_interrupt_exittb(CPUState *cs)
{
if (!kvm_enabled()) {
return;
}
if (!qemu_mutex_iothread_locked()) {
qemu_mutex_lock_iothread();
cpu_interrupt(cs, CPU_INTERRUPT_EXITTB);
qemu_mutex_unlock_iothread();
} else {
cpu_interrupt(cs, CPU_INTERRUPT_EXITTB);
}
}
int hreg_store_msr(CPUPPCState *env, target_ulong value, int alter_hv)
{
int excp;
#if !defined(CONFIG_USER_ONLY)
CPUState *cs = env_cpu(env);
#endif
excp = 0;
value &= env->msr_mask;
#if !defined(CONFIG_USER_ONLY)
/* Neither mtmsr nor guest state can alter HV */
if (!alter_hv || !(env->msr & MSR_HVB)) {
value &= ~MSR_HVB;
value |= env->msr & MSR_HVB;
}
if (((value >> MSR_IR) & 1) != msr_ir ||
((value >> MSR_DR) & 1) != msr_dr) {
cpu_interrupt_exittb(cs);
}
if ((env->mmu_model & POWERPC_MMU_BOOKE) &&
((value >> MSR_GS) & 1) != msr_gs) {
cpu_interrupt_exittb(cs);
}
if (unlikely((env->flags & POWERPC_FLAG_TGPR) &&
((value ^ env->msr) & (1 << MSR_TGPR)))) {
/* Swap temporary saved registers with GPRs */
hreg_swap_gpr_tgpr(env);
}
if (unlikely((value >> MSR_EP) & 1) != msr_ep) {
/* Change the exception prefix on PowerPC 601 */
env->excp_prefix = ((value >> MSR_EP) & 1) * 0xFFF00000;
}
/*
* If PR=1 then EE, IR and DR must be 1
*
* Note: We only enforce this on 64-bit server processors.
* It appears that:
* - 32-bit implementations supports PR=1 and EE/DR/IR=0 and MacOS
* exploits it.
* - 64-bit embedded implementations do not need any operation to be
* performed when PR is set.
*/
if (is_book3s_arch2x(env) && ((value >> MSR_PR) & 1)) {
value |= (1 << MSR_EE) | (1 << MSR_DR) | (1 << MSR_IR);
}
#endif
env->msr = value;
hreg_compute_hflags(env);
#if !defined(CONFIG_USER_ONLY)
if (unlikely(msr_pow == 1)) {
if (!env->pending_interrupts && (*env->check_pow)(env)) {
cs->halted = 1;
excp = EXCP_HALTED;
}
}
#endif
return excp;
}
#ifndef CONFIG_USER_ONLY
void check_tlb_flush(CPUPPCState *env, bool global)
{
CPUState *cs = env_cpu(env);
/* Handle global flushes first */
if (global && (env->tlb_need_flush & TLB_NEED_GLOBAL_FLUSH)) {
env->tlb_need_flush &= ~TLB_NEED_GLOBAL_FLUSH;
env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
tlb_flush_all_cpus_synced(cs);
return;
}
/* Then handle local ones */
if (env->tlb_need_flush & TLB_NEED_LOCAL_FLUSH) {
env->tlb_need_flush &= ~TLB_NEED_LOCAL_FLUSH;
tlb_flush(cs);
}
}
#endif