qemu/target/ppc/mem_helper.c
Richard Henderson f6bcc5b8f9 target/ppc: Improve helper_dcbz for user-only
Mark the reserve_addr check unlikely.  Use tlb_vaddr_to_host
instead of probe_write, relying on the memset itself to test
for page writability.  Use set/clear_helper_retaddr so that
we can properly unwind on segfault.

With this, a trivial loop around guest memset will no longer
spend nearly 25% of runtime within page_get_flags.

Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
2024-07-23 10:56:16 +10:00

539 lines
19 KiB
C

/*
* PowerPC memory access emulation 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 "exec/exec-all.h"
#include "qemu/host-utils.h"
#include "exec/helper-proto.h"
#include "helper_regs.h"
#include "exec/cpu_ldst.h"
#include "internal.h"
#include "qemu/atomic128.h"
/* #define DEBUG_OP */
static inline bool needs_byteswap(const CPUPPCState *env)
{
#if TARGET_BIG_ENDIAN
return FIELD_EX64(env->msr, MSR, LE);
#else
return !FIELD_EX64(env->msr, MSR, LE);
#endif
}
/*****************************************************************************/
/* Memory load and stores */
static inline target_ulong addr_add(CPUPPCState *env, target_ulong addr,
target_long arg)
{
#if defined(TARGET_PPC64)
if (!msr_is_64bit(env, env->msr)) {
return (uint32_t)(addr + arg);
} else
#endif
{
return addr + arg;
}
}
static void *probe_contiguous(CPUPPCState *env, target_ulong addr, uint32_t nb,
MMUAccessType access_type, int mmu_idx,
uintptr_t raddr)
{
void *host1, *host2;
uint32_t nb_pg1, nb_pg2;
nb_pg1 = -(addr | TARGET_PAGE_MASK);
if (likely(nb <= nb_pg1)) {
/* The entire operation is on a single page. */
return probe_access(env, addr, nb, access_type, mmu_idx, raddr);
}
/* The operation spans two pages. */
nb_pg2 = nb - nb_pg1;
host1 = probe_access(env, addr, nb_pg1, access_type, mmu_idx, raddr);
addr = addr_add(env, addr, nb_pg1);
host2 = probe_access(env, addr, nb_pg2, access_type, mmu_idx, raddr);
/* If the two host pages are contiguous, optimize. */
if (host2 == host1 + nb_pg1) {
return host1;
}
return NULL;
}
void helper_lmw(CPUPPCState *env, target_ulong addr, uint32_t reg)
{
uintptr_t raddr = GETPC();
int mmu_idx = ppc_env_mmu_index(env, false);
void *host = probe_contiguous(env, addr, (32 - reg) * 4,
MMU_DATA_LOAD, mmu_idx, raddr);
if (likely(host)) {
/* Fast path -- the entire operation is in RAM at host. */
for (; reg < 32; reg++) {
env->gpr[reg] = (uint32_t)ldl_be_p(host);
host += 4;
}
} else {
/* Slow path -- at least some of the operation requires i/o. */
for (; reg < 32; reg++) {
env->gpr[reg] = cpu_ldl_mmuidx_ra(env, addr, mmu_idx, raddr);
addr = addr_add(env, addr, 4);
}
}
}
void helper_stmw(CPUPPCState *env, target_ulong addr, uint32_t reg)
{
uintptr_t raddr = GETPC();
int mmu_idx = ppc_env_mmu_index(env, false);
void *host = probe_contiguous(env, addr, (32 - reg) * 4,
MMU_DATA_STORE, mmu_idx, raddr);
if (likely(host)) {
/* Fast path -- the entire operation is in RAM at host. */
for (; reg < 32; reg++) {
stl_be_p(host, env->gpr[reg]);
host += 4;
}
} else {
/* Slow path -- at least some of the operation requires i/o. */
for (; reg < 32; reg++) {
cpu_stl_mmuidx_ra(env, addr, env->gpr[reg], mmu_idx, raddr);
addr = addr_add(env, addr, 4);
}
}
}
static void do_lsw(CPUPPCState *env, target_ulong addr, uint32_t nb,
uint32_t reg, uintptr_t raddr)
{
int mmu_idx;
void *host;
uint32_t val;
if (unlikely(nb == 0)) {
return;
}
mmu_idx = ppc_env_mmu_index(env, false);
host = probe_contiguous(env, addr, nb, MMU_DATA_LOAD, mmu_idx, raddr);
if (likely(host)) {
/* Fast path -- the entire operation is in RAM at host. */
for (; nb > 3; nb -= 4) {
env->gpr[reg] = (uint32_t)ldl_be_p(host);
reg = (reg + 1) % 32;
host += 4;
}
switch (nb) {
default:
return;
case 1:
val = ldub_p(host) << 24;
break;
case 2:
val = lduw_be_p(host) << 16;
break;
case 3:
val = (lduw_be_p(host) << 16) | (ldub_p(host + 2) << 8);
break;
}
} else {
/* Slow path -- at least some of the operation requires i/o. */
for (; nb > 3; nb -= 4) {
env->gpr[reg] = cpu_ldl_mmuidx_ra(env, addr, mmu_idx, raddr);
reg = (reg + 1) % 32;
addr = addr_add(env, addr, 4);
}
switch (nb) {
default:
return;
case 1:
val = cpu_ldub_mmuidx_ra(env, addr, mmu_idx, raddr) << 24;
break;
case 2:
val = cpu_lduw_mmuidx_ra(env, addr, mmu_idx, raddr) << 16;
break;
case 3:
val = cpu_lduw_mmuidx_ra(env, addr, mmu_idx, raddr) << 16;
addr = addr_add(env, addr, 2);
val |= cpu_ldub_mmuidx_ra(env, addr, mmu_idx, raddr) << 8;
break;
}
}
env->gpr[reg] = val;
}
void helper_lsw(CPUPPCState *env, target_ulong addr,
uint32_t nb, uint32_t reg)
{
do_lsw(env, addr, nb, reg, GETPC());
}
/*
* PPC32 specification says we must generate an exception if rA is in
* the range of registers to be loaded. In an other hand, IBM says
* this is valid, but rA won't be loaded. For now, I'll follow the
* spec...
*/
void helper_lswx(CPUPPCState *env, target_ulong addr, uint32_t reg,
uint32_t ra, uint32_t rb)
{
if (likely(xer_bc != 0)) {
int num_used_regs = DIV_ROUND_UP(xer_bc, 4);
if (unlikely((ra != 0 && lsw_reg_in_range(reg, num_used_regs, ra)) ||
lsw_reg_in_range(reg, num_used_regs, rb))) {
raise_exception_err_ra(env, POWERPC_EXCP_PROGRAM,
POWERPC_EXCP_INVAL |
POWERPC_EXCP_INVAL_LSWX, GETPC());
} else {
do_lsw(env, addr, xer_bc, reg, GETPC());
}
}
}
void helper_stsw(CPUPPCState *env, target_ulong addr, uint32_t nb,
uint32_t reg)
{
uintptr_t raddr = GETPC();
int mmu_idx;
void *host;
uint32_t val;
if (unlikely(nb == 0)) {
return;
}
mmu_idx = ppc_env_mmu_index(env, false);
host = probe_contiguous(env, addr, nb, MMU_DATA_STORE, mmu_idx, raddr);
if (likely(host)) {
/* Fast path -- the entire operation is in RAM at host. */
for (; nb > 3; nb -= 4) {
stl_be_p(host, env->gpr[reg]);
reg = (reg + 1) % 32;
host += 4;
}
val = env->gpr[reg];
switch (nb) {
case 1:
stb_p(host, val >> 24);
break;
case 2:
stw_be_p(host, val >> 16);
break;
case 3:
stw_be_p(host, val >> 16);
stb_p(host + 2, val >> 8);
break;
}
} else {
for (; nb > 3; nb -= 4) {
cpu_stl_mmuidx_ra(env, addr, env->gpr[reg], mmu_idx, raddr);
reg = (reg + 1) % 32;
addr = addr_add(env, addr, 4);
}
val = env->gpr[reg];
switch (nb) {
case 1:
cpu_stb_mmuidx_ra(env, addr, val >> 24, mmu_idx, raddr);
break;
case 2:
cpu_stw_mmuidx_ra(env, addr, val >> 16, mmu_idx, raddr);
break;
case 3:
cpu_stw_mmuidx_ra(env, addr, val >> 16, mmu_idx, raddr);
addr = addr_add(env, addr, 2);
cpu_stb_mmuidx_ra(env, addr, val >> 8, mmu_idx, raddr);
break;
}
}
}
static void dcbz_common(CPUPPCState *env, target_ulong addr,
int mmu_idx, int dcbz_size, uintptr_t retaddr)
{
target_ulong mask = ~(target_ulong)(dcbz_size - 1);
void *haddr;
/* Align address */
addr &= mask;
/* Check reservation */
if (unlikely((env->reserve_addr & mask) == addr)) {
env->reserve_addr = (target_ulong)-1ULL;
}
/* Try fast path translate */
#ifdef CONFIG_USER_ONLY
haddr = tlb_vaddr_to_host(env, addr, MMU_DATA_STORE, mmu_idx);
#else
haddr = probe_write(env, addr, dcbz_size, mmu_idx, retaddr);
if (unlikely(!haddr)) {
/* Slow path */
for (int i = 0; i < dcbz_size; i += 8) {
cpu_stq_mmuidx_ra(env, addr + i, 0, mmu_idx, retaddr);
}
return;
}
#endif
set_helper_retaddr(retaddr);
memset(haddr, 0, dcbz_size);
clear_helper_retaddr();
}
void helper_dcbz(CPUPPCState *env, target_ulong addr, int mmu_idx)
{
dcbz_common(env, addr, mmu_idx, env->dcache_line_size, GETPC());
}
#ifdef TARGET_PPC64
void helper_dcbzl(CPUPPCState *env, target_ulong addr)
{
int dcbz_size = env->dcache_line_size;
/*
* The translator checked for POWERPC_EXCP_970.
* All that's left is to check HID5.
*/
if (((env->spr[SPR_970_HID5] >> 7) & 0x3) == 1) {
dcbz_size = 32;
}
dcbz_common(env, addr, ppc_env_mmu_index(env, false), dcbz_size, GETPC());
}
#endif
void helper_icbi(CPUPPCState *env, target_ulong addr)
{
addr &= ~(env->dcache_line_size - 1);
/*
* Invalidate one cache line :
* PowerPC specification says this is to be treated like a load
* (not a fetch) by the MMU. To be sure it will be so,
* do the load "by hand".
*/
cpu_ldl_data_ra(env, addr, GETPC());
}
void helper_icbiep(CPUPPCState *env, target_ulong addr)
{
#if !defined(CONFIG_USER_ONLY)
/* See comments above */
addr &= ~(env->dcache_line_size - 1);
cpu_ldl_mmuidx_ra(env, addr, PPC_TLB_EPID_LOAD, GETPC());
#endif
}
/* XXX: to be tested */
target_ulong helper_lscbx(CPUPPCState *env, target_ulong addr, uint32_t reg,
uint32_t ra, uint32_t rb)
{
int i, c, d;
d = 24;
for (i = 0; i < xer_bc; i++) {
c = cpu_ldub_data_ra(env, addr, GETPC());
addr = addr_add(env, addr, 1);
/* ra (if not 0) and rb are never modified */
if (likely(reg != rb && (ra == 0 || reg != ra))) {
env->gpr[reg] = (env->gpr[reg] & ~(0xFF << d)) | (c << d);
}
if (unlikely(c == xer_cmp)) {
break;
}
if (likely(d != 0)) {
d -= 8;
} else {
d = 24;
reg++;
reg = reg & 0x1F;
}
}
return i;
}
/*****************************************************************************/
/* Altivec extension helpers */
#if HOST_BIG_ENDIAN
#define HI_IDX 0
#define LO_IDX 1
#else
#define HI_IDX 1
#define LO_IDX 0
#endif
/*
* We use MSR_LE to determine index ordering in a vector. However,
* byteswapping is not simply controlled by MSR_LE. We also need to
* take into account endianness of the target. This is done for the
* little-endian PPC64 user-mode target.
*/
#define LVE(name, access, swap, element) \
void helper_##name(CPUPPCState *env, ppc_avr_t *r, \
target_ulong addr) \
{ \
size_t n_elems = ARRAY_SIZE(r->element); \
int adjust = HI_IDX * (n_elems - 1); \
int sh = sizeof(r->element[0]) >> 1; \
int index = (addr & 0xf) >> sh; \
if (FIELD_EX64(env->msr, MSR, LE)) { \
index = n_elems - index - 1; \
} \
\
if (needs_byteswap(env)) { \
r->element[LO_IDX ? index : (adjust - index)] = \
swap(access(env, addr, GETPC())); \
} else { \
r->element[LO_IDX ? index : (adjust - index)] = \
access(env, addr, GETPC()); \
} \
}
#define I(x) (x)
LVE(LVEBX, cpu_ldub_data_ra, I, u8)
LVE(LVEHX, cpu_lduw_data_ra, bswap16, u16)
LVE(LVEWX, cpu_ldl_data_ra, bswap32, u32)
#undef I
#undef LVE
#define STVE(name, access, swap, element) \
void helper_##name(CPUPPCState *env, ppc_avr_t *r, \
target_ulong addr) \
{ \
size_t n_elems = ARRAY_SIZE(r->element); \
int adjust = HI_IDX * (n_elems - 1); \
int sh = sizeof(r->element[0]) >> 1; \
int index = (addr & 0xf) >> sh; \
if (FIELD_EX64(env->msr, MSR, LE)) { \
index = n_elems - index - 1; \
} \
\
if (needs_byteswap(env)) { \
access(env, addr, swap(r->element[LO_IDX ? index : \
(adjust - index)]), \
GETPC()); \
} else { \
access(env, addr, r->element[LO_IDX ? index : \
(adjust - index)], GETPC()); \
} \
}
#define I(x) (x)
STVE(STVEBX, cpu_stb_data_ra, I, u8)
STVE(STVEHX, cpu_stw_data_ra, bswap16, u16)
STVE(STVEWX, cpu_stl_data_ra, bswap32, u32)
#undef I
#undef LVE
#ifdef TARGET_PPC64
#define GET_NB(rb) ((rb >> 56) & 0xFF)
#define VSX_LXVL(name, lj) \
void helper_##name(CPUPPCState *env, target_ulong addr, \
ppc_vsr_t *xt, target_ulong rb) \
{ \
ppc_vsr_t t; \
uint64_t nb = GET_NB(rb); \
int i; \
\
t.s128 = int128_zero(); \
if (nb) { \
nb = (nb >= 16) ? 16 : nb; \
if (FIELD_EX64(env->msr, MSR, LE) && !lj) { \
for (i = 16; i > 16 - nb; i--) { \
t.VsrB(i - 1) = cpu_ldub_data_ra(env, addr, GETPC()); \
addr = addr_add(env, addr, 1); \
} \
} else { \
for (i = 0; i < nb; i++) { \
t.VsrB(i) = cpu_ldub_data_ra(env, addr, GETPC()); \
addr = addr_add(env, addr, 1); \
} \
} \
} \
*xt = t; \
}
VSX_LXVL(lxvl, 0)
VSX_LXVL(lxvll, 1)
#undef VSX_LXVL
#define VSX_STXVL(name, lj) \
void helper_##name(CPUPPCState *env, target_ulong addr, \
ppc_vsr_t *xt, target_ulong rb) \
{ \
target_ulong nb = GET_NB(rb); \
int i; \
\
if (!nb) { \
return; \
} \
\
nb = (nb >= 16) ? 16 : nb; \
if (FIELD_EX64(env->msr, MSR, LE) && !lj) { \
for (i = 16; i > 16 - nb; i--) { \
cpu_stb_data_ra(env, addr, xt->VsrB(i - 1), GETPC()); \
addr = addr_add(env, addr, 1); \
} \
} else { \
for (i = 0; i < nb; i++) { \
cpu_stb_data_ra(env, addr, xt->VsrB(i), GETPC()); \
addr = addr_add(env, addr, 1); \
} \
} \
}
VSX_STXVL(stxvl, 0)
VSX_STXVL(stxvll, 1)
#undef VSX_STXVL
#undef GET_NB
#endif /* TARGET_PPC64 */
#undef HI_IDX
#undef LO_IDX
void helper_tbegin(CPUPPCState *env)
{
/*
* As a degenerate implementation, always fail tbegin. The reason
* given is "Nesting overflow". The "persistent" bit is set,
* providing a hint to the error handler to not retry. The TFIAR
* captures the address of the failure, which is this tbegin
* instruction. Instruction execution will continue with the next
* instruction in memory, which is precisely what we want.
*/
env->spr[SPR_TEXASR] =
(1ULL << TEXASR_FAILURE_PERSISTENT) |
(1ULL << TEXASR_NESTING_OVERFLOW) |
(FIELD_EX64_HV(env->msr) << TEXASR_PRIVILEGE_HV) |
(FIELD_EX64(env->msr, MSR, PR) << TEXASR_PRIVILEGE_PR) |
(1ULL << TEXASR_FAILURE_SUMMARY) |
(1ULL << TEXASR_TFIAR_EXACT);
env->spr[SPR_TFIAR] = env->nip | (FIELD_EX64_HV(env->msr) << 1) |
FIELD_EX64(env->msr, MSR, PR);
env->spr[SPR_TFHAR] = env->nip + 4;
env->crf[0] = 0xB; /* 0b1010 = transaction failure */
}