qemu-e2k/target/ppc/mmu-hash32.c
Benjamin Herrenschmidt 6e8a65abbb ppc/hash32: Rework R and C bit updates
With MT-TCG, we are now running translation in a racy way, thus
we need to mimic hardware when it comes to updating the R and
C bits, by doing byte stores.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Cédric Le Goater <clg@kaod.org>
Message-Id: <20190411080004.8690-5-clg@kaod.org>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
2019-04-26 11:37:57 +10:00

598 lines
17 KiB
C

/*
* PowerPC MMU, TLB and BAT emulation helpers for QEMU.
*
* Copyright (c) 2003-2007 Jocelyn Mayer
* Copyright (c) 2013 David Gibson, IBM Corporation
*
* 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 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 "exec/helper-proto.h"
#include "sysemu/kvm.h"
#include "kvm_ppc.h"
#include "mmu-hash32.h"
#include "exec/log.h"
/* #define DEBUG_BAT */
#ifdef DEBUG_BATS
# define LOG_BATS(...) qemu_log_mask(CPU_LOG_MMU, __VA_ARGS__)
#else
# define LOG_BATS(...) do { } while (0)
#endif
struct mmu_ctx_hash32 {
hwaddr raddr; /* Real address */
int prot; /* Protection bits */
int key; /* Access key */
};
static int ppc_hash32_pp_prot(int key, int pp, int nx)
{
int prot;
if (key == 0) {
switch (pp) {
case 0x0:
case 0x1:
case 0x2:
prot = PAGE_READ | PAGE_WRITE;
break;
case 0x3:
prot = PAGE_READ;
break;
default:
abort();
}
} else {
switch (pp) {
case 0x0:
prot = 0;
break;
case 0x1:
case 0x3:
prot = PAGE_READ;
break;
case 0x2:
prot = PAGE_READ | PAGE_WRITE;
break;
default:
abort();
}
}
if (nx == 0) {
prot |= PAGE_EXEC;
}
return prot;
}
static int ppc_hash32_pte_prot(PowerPCCPU *cpu,
target_ulong sr, ppc_hash_pte32_t pte)
{
CPUPPCState *env = &cpu->env;
unsigned pp, key;
key = !!(msr_pr ? (sr & SR32_KP) : (sr & SR32_KS));
pp = pte.pte1 & HPTE32_R_PP;
return ppc_hash32_pp_prot(key, pp, !!(sr & SR32_NX));
}
static target_ulong hash32_bat_size(PowerPCCPU *cpu,
target_ulong batu, target_ulong batl)
{
CPUPPCState *env = &cpu->env;
if ((msr_pr && !(batu & BATU32_VP))
|| (!msr_pr && !(batu & BATU32_VS))) {
return 0;
}
return BATU32_BEPI & ~((batu & BATU32_BL) << 15);
}
static int hash32_bat_prot(PowerPCCPU *cpu,
target_ulong batu, target_ulong batl)
{
int pp, prot;
prot = 0;
pp = batl & BATL32_PP;
if (pp != 0) {
prot = PAGE_READ | PAGE_EXEC;
if (pp == 0x2) {
prot |= PAGE_WRITE;
}
}
return prot;
}
static target_ulong hash32_bat_601_size(PowerPCCPU *cpu,
target_ulong batu, target_ulong batl)
{
if (!(batl & BATL32_601_V)) {
return 0;
}
return BATU32_BEPI & ~((batl & BATL32_601_BL) << 17);
}
static int hash32_bat_601_prot(PowerPCCPU *cpu,
target_ulong batu, target_ulong batl)
{
CPUPPCState *env = &cpu->env;
int key, pp;
pp = batu & BATU32_601_PP;
if (msr_pr == 0) {
key = !!(batu & BATU32_601_KS);
} else {
key = !!(batu & BATU32_601_KP);
}
return ppc_hash32_pp_prot(key, pp, 0);
}
static hwaddr ppc_hash32_bat_lookup(PowerPCCPU *cpu, target_ulong ea, int rwx,
int *prot)
{
CPUPPCState *env = &cpu->env;
target_ulong *BATlt, *BATut;
int i;
LOG_BATS("%s: %cBAT v " TARGET_FMT_lx "\n", __func__,
rwx == 2 ? 'I' : 'D', ea);
if (rwx == 2) {
BATlt = env->IBAT[1];
BATut = env->IBAT[0];
} else {
BATlt = env->DBAT[1];
BATut = env->DBAT[0];
}
for (i = 0; i < env->nb_BATs; i++) {
target_ulong batu = BATut[i];
target_ulong batl = BATlt[i];
target_ulong mask;
if (unlikely(env->mmu_model == POWERPC_MMU_601)) {
mask = hash32_bat_601_size(cpu, batu, batl);
} else {
mask = hash32_bat_size(cpu, batu, batl);
}
LOG_BATS("%s: %cBAT%d v " TARGET_FMT_lx " BATu " TARGET_FMT_lx
" BATl " TARGET_FMT_lx "\n", __func__,
type == ACCESS_CODE ? 'I' : 'D', i, ea, batu, batl);
if (mask && ((ea & mask) == (batu & BATU32_BEPI))) {
hwaddr raddr = (batl & mask) | (ea & ~mask);
if (unlikely(env->mmu_model == POWERPC_MMU_601)) {
*prot = hash32_bat_601_prot(cpu, batu, batl);
} else {
*prot = hash32_bat_prot(cpu, batu, batl);
}
return raddr & TARGET_PAGE_MASK;
}
}
/* No hit */
#if defined(DEBUG_BATS)
if (qemu_log_enabled()) {
LOG_BATS("no BAT match for " TARGET_FMT_lx ":\n", ea);
for (i = 0; i < 4; i++) {
BATu = &BATut[i];
BATl = &BATlt[i];
BEPIu = *BATu & BATU32_BEPIU;
BEPIl = *BATu & BATU32_BEPIL;
bl = (*BATu & 0x00001FFC) << 15;
LOG_BATS("%s: %cBAT%d v " TARGET_FMT_lx " BATu " TARGET_FMT_lx
" BATl " TARGET_FMT_lx "\n\t" TARGET_FMT_lx " "
TARGET_FMT_lx " " TARGET_FMT_lx "\n",
__func__, type == ACCESS_CODE ? 'I' : 'D', i, ea,
*BATu, *BATl, BEPIu, BEPIl, bl);
}
}
#endif
return -1;
}
static int ppc_hash32_direct_store(PowerPCCPU *cpu, target_ulong sr,
target_ulong eaddr, int rwx,
hwaddr *raddr, int *prot)
{
CPUState *cs = CPU(cpu);
CPUPPCState *env = &cpu->env;
int key = !!(msr_pr ? (sr & SR32_KP) : (sr & SR32_KS));
qemu_log_mask(CPU_LOG_MMU, "direct store...\n");
if ((sr & 0x1FF00000) >> 20 == 0x07f) {
/*
* Memory-forced I/O controller interface access
*
* If T=1 and BUID=x'07F', the 601 performs a memory access
* to SR[28-31] LA[4-31], bypassing all protection mechanisms.
*/
*raddr = ((sr & 0xF) << 28) | (eaddr & 0x0FFFFFFF);
*prot = PAGE_READ | PAGE_WRITE | PAGE_EXEC;
return 0;
}
if (rwx == 2) {
/* No code fetch is allowed in direct-store areas */
cs->exception_index = POWERPC_EXCP_ISI;
env->error_code = 0x10000000;
return 1;
}
switch (env->access_type) {
case ACCESS_INT:
/* Integer load/store : only access allowed */
break;
case ACCESS_FLOAT:
/* Floating point load/store */
cs->exception_index = POWERPC_EXCP_ALIGN;
env->error_code = POWERPC_EXCP_ALIGN_FP;
env->spr[SPR_DAR] = eaddr;
return 1;
case ACCESS_RES:
/* lwarx, ldarx or srwcx. */
env->error_code = 0;
env->spr[SPR_DAR] = eaddr;
if (rwx == 1) {
env->spr[SPR_DSISR] = 0x06000000;
} else {
env->spr[SPR_DSISR] = 0x04000000;
}
return 1;
case ACCESS_CACHE:
/*
* dcba, dcbt, dcbtst, dcbf, dcbi, dcbst, dcbz, or icbi
*
* Should make the instruction do no-op. As it already do
* no-op, it's quite easy :-)
*/
*raddr = eaddr;
return 0;
case ACCESS_EXT:
/* eciwx or ecowx */
cs->exception_index = POWERPC_EXCP_DSI;
env->error_code = 0;
env->spr[SPR_DAR] = eaddr;
if (rwx == 1) {
env->spr[SPR_DSISR] = 0x06100000;
} else {
env->spr[SPR_DSISR] = 0x04100000;
}
return 1;
default:
cpu_abort(cs, "ERROR: instruction should not need "
"address translation\n");
}
if ((rwx == 1 || key != 1) && (rwx == 0 || key != 0)) {
*raddr = eaddr;
return 0;
} else {
cs->exception_index = POWERPC_EXCP_DSI;
env->error_code = 0;
env->spr[SPR_DAR] = eaddr;
if (rwx == 1) {
env->spr[SPR_DSISR] = 0x0a000000;
} else {
env->spr[SPR_DSISR] = 0x08000000;
}
return 1;
}
}
hwaddr get_pteg_offset32(PowerPCCPU *cpu, hwaddr hash)
{
target_ulong mask = ppc_hash32_hpt_mask(cpu);
return (hash * HASH_PTEG_SIZE_32) & mask;
}
static hwaddr ppc_hash32_pteg_search(PowerPCCPU *cpu, hwaddr pteg_off,
bool secondary, target_ulong ptem,
ppc_hash_pte32_t *pte)
{
hwaddr pte_offset = pteg_off;
target_ulong pte0, pte1;
int i;
for (i = 0; i < HPTES_PER_GROUP; i++) {
pte0 = ppc_hash32_load_hpte0(cpu, pte_offset);
/*
* pte0 contains the valid bit and must be read before pte1,
* otherwise we might see an old pte1 with a new valid bit and
* thus an inconsistent hpte value
*/
smp_rmb();
pte1 = ppc_hash32_load_hpte1(cpu, pte_offset);
if ((pte0 & HPTE32_V_VALID)
&& (secondary == !!(pte0 & HPTE32_V_SECONDARY))
&& HPTE32_V_COMPARE(pte0, ptem)) {
pte->pte0 = pte0;
pte->pte1 = pte1;
return pte_offset;
}
pte_offset += HASH_PTE_SIZE_32;
}
return -1;
}
static void ppc_hash32_set_r(PowerPCCPU *cpu, hwaddr pte_offset, uint32_t pte1)
{
target_ulong base = ppc_hash32_hpt_base(cpu);
hwaddr offset = pte_offset + 6;
/* The HW performs a non-atomic byte update */
stb_phys(CPU(cpu)->as, base + offset, ((pte1 >> 8) & 0xff) | 0x01);
}
static void ppc_hash32_set_c(PowerPCCPU *cpu, hwaddr pte_offset, uint64_t pte1)
{
target_ulong base = ppc_hash32_hpt_base(cpu);
hwaddr offset = pte_offset + 7;
/* The HW performs a non-atomic byte update */
stb_phys(CPU(cpu)->as, base + offset, (pte1 & 0xff) | 0x80);
}
static hwaddr ppc_hash32_htab_lookup(PowerPCCPU *cpu,
target_ulong sr, target_ulong eaddr,
ppc_hash_pte32_t *pte)
{
hwaddr pteg_off, pte_offset;
hwaddr hash;
uint32_t vsid, pgidx, ptem;
vsid = sr & SR32_VSID;
pgidx = (eaddr & ~SEGMENT_MASK_256M) >> TARGET_PAGE_BITS;
hash = vsid ^ pgidx;
ptem = (vsid << 7) | (pgidx >> 10);
/* Page address translation */
qemu_log_mask(CPU_LOG_MMU, "htab_base " TARGET_FMT_plx
" htab_mask " TARGET_FMT_plx
" hash " TARGET_FMT_plx "\n",
ppc_hash32_hpt_base(cpu), ppc_hash32_hpt_mask(cpu), hash);
/* Primary PTEG lookup */
qemu_log_mask(CPU_LOG_MMU, "0 htab=" TARGET_FMT_plx "/" TARGET_FMT_plx
" vsid=%" PRIx32 " ptem=%" PRIx32
" hash=" TARGET_FMT_plx "\n",
ppc_hash32_hpt_base(cpu), ppc_hash32_hpt_mask(cpu),
vsid, ptem, hash);
pteg_off = get_pteg_offset32(cpu, hash);
pte_offset = ppc_hash32_pteg_search(cpu, pteg_off, 0, ptem, pte);
if (pte_offset == -1) {
/* Secondary PTEG lookup */
qemu_log_mask(CPU_LOG_MMU, "1 htab=" TARGET_FMT_plx "/" TARGET_FMT_plx
" vsid=%" PRIx32 " api=%" PRIx32
" hash=" TARGET_FMT_plx "\n", ppc_hash32_hpt_base(cpu),
ppc_hash32_hpt_mask(cpu), vsid, ptem, ~hash);
pteg_off = get_pteg_offset32(cpu, ~hash);
pte_offset = ppc_hash32_pteg_search(cpu, pteg_off, 1, ptem, pte);
}
return pte_offset;
}
static hwaddr ppc_hash32_pte_raddr(target_ulong sr, ppc_hash_pte32_t pte,
target_ulong eaddr)
{
hwaddr rpn = pte.pte1 & HPTE32_R_RPN;
hwaddr mask = ~TARGET_PAGE_MASK;
return (rpn & ~mask) | (eaddr & mask);
}
int ppc_hash32_handle_mmu_fault(PowerPCCPU *cpu, vaddr eaddr, int rwx,
int mmu_idx)
{
CPUState *cs = CPU(cpu);
CPUPPCState *env = &cpu->env;
target_ulong sr;
hwaddr pte_offset;
ppc_hash_pte32_t pte;
int prot;
const int need_prot[] = {PAGE_READ, PAGE_WRITE, PAGE_EXEC};
hwaddr raddr;
assert((rwx == 0) || (rwx == 1) || (rwx == 2));
/* 1. Handle real mode accesses */
if (((rwx == 2) && (msr_ir == 0)) || ((rwx != 2) && (msr_dr == 0))) {
/* Translation is off */
raddr = eaddr;
tlb_set_page(cs, eaddr & TARGET_PAGE_MASK, raddr & TARGET_PAGE_MASK,
PAGE_READ | PAGE_WRITE | PAGE_EXEC, mmu_idx,
TARGET_PAGE_SIZE);
return 0;
}
/* 2. Check Block Address Translation entries (BATs) */
if (env->nb_BATs != 0) {
raddr = ppc_hash32_bat_lookup(cpu, eaddr, rwx, &prot);
if (raddr != -1) {
if (need_prot[rwx] & ~prot) {
if (rwx == 2) {
cs->exception_index = POWERPC_EXCP_ISI;
env->error_code = 0x08000000;
} else {
cs->exception_index = POWERPC_EXCP_DSI;
env->error_code = 0;
env->spr[SPR_DAR] = eaddr;
if (rwx == 1) {
env->spr[SPR_DSISR] = 0x0a000000;
} else {
env->spr[SPR_DSISR] = 0x08000000;
}
}
return 1;
}
tlb_set_page(cs, eaddr & TARGET_PAGE_MASK,
raddr & TARGET_PAGE_MASK, prot, mmu_idx,
TARGET_PAGE_SIZE);
return 0;
}
}
/* 3. Look up the Segment Register */
sr = env->sr[eaddr >> 28];
/* 4. Handle direct store segments */
if (sr & SR32_T) {
if (ppc_hash32_direct_store(cpu, sr, eaddr, rwx,
&raddr, &prot) == 0) {
tlb_set_page(cs, eaddr & TARGET_PAGE_MASK,
raddr & TARGET_PAGE_MASK, prot, mmu_idx,
TARGET_PAGE_SIZE);
return 0;
} else {
return 1;
}
}
/* 5. Check for segment level no-execute violation */
if ((rwx == 2) && (sr & SR32_NX)) {
cs->exception_index = POWERPC_EXCP_ISI;
env->error_code = 0x10000000;
return 1;
}
/* 6. Locate the PTE in the hash table */
pte_offset = ppc_hash32_htab_lookup(cpu, sr, eaddr, &pte);
if (pte_offset == -1) {
if (rwx == 2) {
cs->exception_index = POWERPC_EXCP_ISI;
env->error_code = 0x40000000;
} else {
cs->exception_index = POWERPC_EXCP_DSI;
env->error_code = 0;
env->spr[SPR_DAR] = eaddr;
if (rwx == 1) {
env->spr[SPR_DSISR] = 0x42000000;
} else {
env->spr[SPR_DSISR] = 0x40000000;
}
}
return 1;
}
qemu_log_mask(CPU_LOG_MMU,
"found PTE at offset %08" HWADDR_PRIx "\n", pte_offset);
/* 7. Check access permissions */
prot = ppc_hash32_pte_prot(cpu, sr, pte);
if (need_prot[rwx] & ~prot) {
/* Access right violation */
qemu_log_mask(CPU_LOG_MMU, "PTE access rejected\n");
if (rwx == 2) {
cs->exception_index = POWERPC_EXCP_ISI;
env->error_code = 0x08000000;
} else {
cs->exception_index = POWERPC_EXCP_DSI;
env->error_code = 0;
env->spr[SPR_DAR] = eaddr;
if (rwx == 1) {
env->spr[SPR_DSISR] = 0x0a000000;
} else {
env->spr[SPR_DSISR] = 0x08000000;
}
}
return 1;
}
qemu_log_mask(CPU_LOG_MMU, "PTE access granted !\n");
/* 8. Update PTE referenced and changed bits if necessary */
if (!(pte.pte1 & HPTE32_R_R)) {
ppc_hash32_set_r(cpu, pte_offset, pte.pte1);
}
if (!(pte.pte1 & HPTE32_R_C)) {
if (rwx == 1) {
ppc_hash32_set_c(cpu, pte_offset, pte.pte1);
} else {
/*
* Treat the page as read-only for now, so that a later write
* will pass through this function again to set the C bit
*/
prot &= ~PAGE_WRITE;
}
}
/* 9. Determine the real address from the PTE */
raddr = ppc_hash32_pte_raddr(sr, pte, eaddr);
tlb_set_page(cs, eaddr & TARGET_PAGE_MASK, raddr & TARGET_PAGE_MASK,
prot, mmu_idx, TARGET_PAGE_SIZE);
return 0;
}
hwaddr ppc_hash32_get_phys_page_debug(PowerPCCPU *cpu, target_ulong eaddr)
{
CPUPPCState *env = &cpu->env;
target_ulong sr;
hwaddr pte_offset;
ppc_hash_pte32_t pte;
int prot;
if (msr_dr == 0) {
/* Translation is off */
return eaddr;
}
if (env->nb_BATs != 0) {
hwaddr raddr = ppc_hash32_bat_lookup(cpu, eaddr, 0, &prot);
if (raddr != -1) {
return raddr;
}
}
sr = env->sr[eaddr >> 28];
if (sr & SR32_T) {
/* FIXME: Add suitable debug support for Direct Store segments */
return -1;
}
pte_offset = ppc_hash32_htab_lookup(cpu, sr, eaddr, &pte);
if (pte_offset == -1) {
return -1;
}
return ppc_hash32_pte_raddr(sr, pte, eaddr) & TARGET_PAGE_MASK;
}