OpenE2K
/
qemu-e2k
13
4
Fork 0
Code Issues 4 Pull Requests Projects 2 Releases Activity
qemu-e2k/target/nios2/helper.c

373 lines
11 KiB
C
Raw Blame History

/*
* Altera Nios II helper routines.
*
* Copyright (c) 2012 Chris Wulff <crwulff@gmail.com>
*
* 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/lgpl-2.1.html>
*/
#include "qemu/osdep.h"
#include "cpu.h"
#include "qemu/host-utils.h"
#include "exec/exec-all.h"
#include "exec/cpu_ldst.h"
#include "exec/log.h"
#include "exec/helper-proto.h"
#include "semihosting/semihost.h"
static void do_exception(Nios2CPU *cpu, uint32_t exception_addr,
uint32_t tlbmisc_set, bool is_break)
{
CPUNios2State *env = &cpu->env;
CPUState *cs = CPU(cpu);
uint32_t old_status = env->ctrl[CR_STATUS];
uint32_t new_status = old_status;
/* With shadow regs, exceptions are always taken into CRS 0. */
new_status &= ~R_CR_STATUS_CRS_MASK;
env->regs = env->shadow_regs[0];
if ((old_status & CR_STATUS_EH) == 0) {
int r_ea = R_EA, cr_es = CR_ESTATUS;
if (is_break) {
r_ea = R_BA;
cr_es = CR_BSTATUS;
}
env->ctrl[cr_es] = old_status;
env->regs[r_ea] = env->pc;
if (cpu->mmu_present) {
new_status |= CR_STATUS_EH;
/*
* There are 4 bits that are always written.
* Explicitly clear them, to be set via the argument.
*/
env->ctrl[CR_TLBMISC] &= ~(CR_TLBMISC_D |
CR_TLBMISC_PERM |
CR_TLBMISC_BAD |
CR_TLBMISC_DBL);
env->ctrl[CR_TLBMISC] |= tlbmisc_set;
}
/*
* With shadow regs, and EH == 0, PRS is set from CRS.
* At least, so says Table 3-9, and some other text,
* though Table 3-38 says otherwise.
*/
new_status = FIELD_DP32(new_status, CR_STATUS, PRS,
FIELD_EX32(old_status, CR_STATUS, CRS));
}
new_status &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->ctrl[CR_STATUS] = new_status;
if (!is_break) {
env->ctrl[CR_EXCEPTION] = FIELD_DP32(0, CR_EXCEPTION, CAUSE,
cs->exception_index);
}
env->pc = exception_addr;
}
static void do_iic_irq(Nios2CPU *cpu)
{
do_exception(cpu, cpu->exception_addr, 0, false);
}
static void do_eic_irq(Nios2CPU *cpu)
{
CPUNios2State *env = &cpu->env;
uint32_t old_status = env->ctrl[CR_STATUS];
uint32_t new_status = old_status;
uint32_t old_rs = FIELD_EX32(old_status, CR_STATUS, CRS);
uint32_t new_rs = cpu->rrs;
new_status = FIELD_DP32(new_status, CR_STATUS, CRS, new_rs);
new_status = FIELD_DP32(new_status, CR_STATUS, IL, cpu->ril);
new_status = FIELD_DP32(new_status, CR_STATUS, NMI, cpu->rnmi);
new_status &= ~(CR_STATUS_RSIE | CR_STATUS_U);
new_status |= CR_STATUS_IH;
if (!(new_status & CR_STATUS_EH)) {
new_status = FIELD_DP32(new_status, CR_STATUS, PRS, old_rs);
if (new_rs == 0) {
env->ctrl[CR_ESTATUS] = old_status;
} else {
if (new_rs != old_rs) {
old_status |= CR_STATUS_SRS;
}
env->shadow_regs[new_rs][R_SSTATUS] = old_status;
}
env->shadow_regs[new_rs][R_EA] = env->pc;
}
env->ctrl[CR_STATUS] = new_status;
nios2_update_crs(env);
env->pc = cpu->rha;
}
void nios2_cpu_do_interrupt(CPUState *cs)
{
Nios2CPU *cpu = NIOS2_CPU(cs);
CPUNios2State *env = &cpu->env;
uint32_t tlbmisc_set = 0;
if (qemu_loglevel_mask(CPU_LOG_INT)) {
const char *name = NULL;
switch (cs->exception_index) {
case EXCP_IRQ:
name = "interrupt";
break;
case EXCP_TLB_X:
case EXCP_TLB_D:
if (env->ctrl[CR_STATUS] & CR_STATUS_EH) {
name = "TLB MISS (double)";
} else {
name = "TLB MISS (fast)";
}
break;
case EXCP_PERM_R:
case EXCP_PERM_W:
case EXCP_PERM_X:
name = "TLB PERM";
break;
case EXCP_SUPERA_X:
case EXCP_SUPERA_D:
name = "SUPERVISOR (address)";
break;
case EXCP_SUPERI:
name = "SUPERVISOR (insn)";
break;
case EXCP_ILLEGAL:
name = "ILLEGAL insn";
break;
case EXCP_UNALIGN:
name = "Misaligned (data)";
break;
case EXCP_UNALIGND:
name = "Misaligned (destination)";
break;
case EXCP_DIV:
name = "DIV error";
break;
case EXCP_TRAP:
name = "TRAP insn";
break;
case EXCP_BREAK:
name = "BREAK insn";
break;
case EXCP_SEMIHOST:
name = "SEMIHOST insn";
break;
}
if (name) {
qemu_log("%s at pc=0x%08x\n", name, env->pc);
} else {
qemu_log("Unknown exception %d at pc=0x%08x\n",
cs->exception_index, env->pc);
}
}
switch (cs->exception_index) {
case EXCP_IRQ:
/* Note that PC is advanced for interrupts as well. */
env->pc += 4;
if (cpu->eic_present) {
do_eic_irq(cpu);
} else {
do_iic_irq(cpu);
}
break;
case EXCP_TLB_D:
tlbmisc_set = CR_TLBMISC_D;
/* fall through */
case EXCP_TLB_X:
if (env->ctrl[CR_STATUS] & CR_STATUS_EH) {
tlbmisc_set |= CR_TLBMISC_DBL;
/*
* Normally, we don't write to tlbmisc unless !EH,
* so do it manually for the double-tlb miss exception.
*/
env->ctrl[CR_TLBMISC] &= ~(CR_TLBMISC_D |
CR_TLBMISC_PERM |
CR_TLBMISC_BAD);
env->ctrl[CR_TLBMISC] |= tlbmisc_set;
do_exception(cpu, cpu->exception_addr, 0, false);
} else {
tlbmisc_set |= CR_TLBMISC_WE;
do_exception(cpu, cpu->fast_tlb_miss_addr, tlbmisc_set, false);
}
break;
case EXCP_PERM_R:
case EXCP_PERM_W:
tlbmisc_set = CR_TLBMISC_D;
/* fall through */
case EXCP_PERM_X:
tlbmisc_set |= CR_TLBMISC_PERM;
if (!(env->ctrl[CR_STATUS] & CR_STATUS_EH)) {
tlbmisc_set |= CR_TLBMISC_WE;
}
do_exception(cpu, cpu->exception_addr, tlbmisc_set, false);
break;
case EXCP_SUPERA_D:
case EXCP_UNALIGN:
tlbmisc_set = CR_TLBMISC_D;
/* fall through */
case EXCP_SUPERA_X:
case EXCP_UNALIGND:
tlbmisc_set |= CR_TLBMISC_BAD;
do_exception(cpu, cpu->exception_addr, tlbmisc_set, false);
break;
case EXCP_SUPERI:
case EXCP_ILLEGAL:
case EXCP_DIV:
case EXCP_TRAP:
do_exception(cpu, cpu->exception_addr, 0, false);
break;
case EXCP_BREAK:
do_exception(cpu, cpu->exception_addr, 0, true);
break;
case EXCP_SEMIHOST:
do_nios2_semihosting(env);
break;
default:
cpu_abort(cs, "unhandled exception type=%d\n", cs->exception_index);
}
}
hwaddr nios2_cpu_get_phys_page_debug(CPUState *cs, vaddr addr)
{
Nios2CPU *cpu = NIOS2_CPU(cs);
CPUNios2State *env = &cpu->env;
target_ulong vaddr, paddr = 0;
Nios2MMULookup lu;
unsigned int hit;
if (cpu->mmu_present && (addr < 0xC0000000)) {
hit = mmu_translate(env, &lu, addr, 0, 0);
if (hit) {
vaddr = addr & TARGET_PAGE_MASK;
paddr = lu.paddr + vaddr - lu.vaddr;
} else {
paddr = -1;
qemu_log("cpu_get_phys_page debug MISS: %#" PRIx64 "\n", addr);
}
} else {
paddr = addr & TARGET_PAGE_MASK;
}
return paddr;
}
void nios2_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
MMUAccessType access_type,
int mmu_idx, uintptr_t retaddr)
{
Nios2CPU *cpu = NIOS2_CPU(cs);
CPUNios2State *env = &cpu->env;
env->ctrl[CR_BADADDR] = addr;
cs->exception_index = EXCP_UNALIGN;
nios2_cpu_loop_exit_advance(env, retaddr);
}
bool nios2_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr)
{
Nios2CPU *cpu = NIOS2_CPU(cs);
CPUNios2State *env = &cpu->env;
unsigned int excp;
target_ulong vaddr, paddr;
Nios2MMULookup lu;
unsigned int hit;
if (!cpu->mmu_present) {
/* No MMU */
address &= TARGET_PAGE_MASK;
tlb_set_page(cs, address, address, PAGE_BITS,
mmu_idx, TARGET_PAGE_SIZE);
return true;
}
if (MMU_SUPERVISOR_IDX == mmu_idx) {
if (address >= 0xC0000000) {
/* Kernel physical page - TLB bypassed */
address &= TARGET_PAGE_MASK;
tlb_set_page(cs, address, address, PAGE_BITS,
mmu_idx, TARGET_PAGE_SIZE);
return true;
}
} else {
if (address >= 0x80000000) {
/* Illegal access from user mode */
if (probe) {
return false;
}
cs->exception_index = (access_type == MMU_INST_FETCH
? EXCP_SUPERA_X : EXCP_SUPERA_D);
env->ctrl[CR_BADADDR] = address;
nios2_cpu_loop_exit_advance(env, retaddr);
}
}
/* Virtual page. */
hit = mmu_translate(env, &lu, address, access_type, mmu_idx);
if (hit) {
vaddr = address & TARGET_PAGE_MASK;
paddr = lu.paddr + vaddr - lu.vaddr;
if (((access_type == MMU_DATA_LOAD) && (lu.prot & PAGE_READ)) ||
((access_type == MMU_DATA_STORE) && (lu.prot & PAGE_WRITE)) ||
((access_type == MMU_INST_FETCH) && (lu.prot & PAGE_EXEC))) {
tlb_set_page(cs, vaddr, paddr, lu.prot,
mmu_idx, TARGET_PAGE_SIZE);
return true;
}
/* Permission violation */
excp = (access_type == MMU_DATA_LOAD ? EXCP_PERM_R :
access_type == MMU_DATA_STORE ? EXCP_PERM_W : EXCP_PERM_X);
} else {
excp = (access_type == MMU_INST_FETCH ? EXCP_TLB_X: EXCP_TLB_D);
}
if (probe) {
return false;
}
env->ctrl[CR_TLBMISC] = FIELD_DP32(env->ctrl[CR_TLBMISC], CR_TLBMISC, D,
access_type != MMU_INST_FETCH);
env->ctrl[CR_PTEADDR] = FIELD_DP32(env->ctrl[CR_PTEADDR], CR_PTEADDR, VPN,
address >> TARGET_PAGE_BITS);
env->mmu.pteaddr_wr = env->ctrl[CR_PTEADDR];
cs->exception_index = excp;
env->ctrl[CR_BADADDR] = address;
nios2_cpu_loop_exit_advance(env, retaddr);
}
Reference in New Issue View Git Blame Copy Permalink