xemu/target/nios2/helper.c
Alex Bennée f1672e6f2b semihosting: move semihosting configuration into its own directory
In preparation for having some more common semihosting code let's
excise the current config magic from vl.c into its own file. We shall
later add more conditionals to the build configurations so we can
avoid building this if we don't need it.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Tested-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
2019-05-28 10:28:50 +01:00

315 lines
9.9 KiB
C

/*
* 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 "hw/semihosting/semihost.h"
#if defined(CONFIG_USER_ONLY)
void nios2_cpu_do_interrupt(CPUState *cs)
{
Nios2CPU *cpu = NIOS2_CPU(cs);
CPUNios2State *env = &cpu->env;
cs->exception_index = -1;
env->regs[R_EA] = env->regs[R_PC] + 4;
}
bool nios2_cpu_tlb_fill(CPUState *cs, vaddr address, int size,
MMUAccessType access_type, int mmu_idx,
bool probe, uintptr_t retaddr)
{
cs->exception_index = 0xaa;
cpu_loop_exit_restore(cs, retaddr);
}
#else /* !CONFIG_USER_ONLY */
void nios2_cpu_do_interrupt(CPUState *cs)
{
Nios2CPU *cpu = NIOS2_CPU(cs);
CPUNios2State *env = &cpu->env;
switch (cs->exception_index) {
case EXCP_IRQ:
assert(env->regs[CR_STATUS] & CR_STATUS_PIE);
qemu_log_mask(CPU_LOG_INT, "interrupt at pc=%x\n", env->regs[R_PC]);
env->regs[CR_ESTATUS] = env->regs[CR_STATUS];
env->regs[CR_STATUS] |= CR_STATUS_IH;
env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->regs[CR_EXCEPTION] &= ~(0x1F << 2);
env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2;
env->regs[R_EA] = env->regs[R_PC] + 4;
env->regs[R_PC] = cpu->exception_addr;
break;
case EXCP_TLBD:
if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) {
qemu_log_mask(CPU_LOG_INT, "TLB MISS (fast) at pc=%x\n",
env->regs[R_PC]);
/* Fast TLB miss */
/* Variation from the spec. Table 3-35 of the cpu reference shows
* estatus not being changed for TLB miss but this appears to
* be incorrect. */
env->regs[CR_ESTATUS] = env->regs[CR_STATUS];
env->regs[CR_STATUS] |= CR_STATUS_EH;
env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->regs[CR_EXCEPTION] &= ~(0x1F << 2);
env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2;
env->regs[CR_TLBMISC] &= ~CR_TLBMISC_DBL;
env->regs[CR_TLBMISC] |= CR_TLBMISC_WR;
env->regs[R_EA] = env->regs[R_PC] + 4;
env->regs[R_PC] = cpu->fast_tlb_miss_addr;
} else {
qemu_log_mask(CPU_LOG_INT, "TLB MISS (double) at pc=%x\n",
env->regs[R_PC]);
/* Double TLB miss */
env->regs[CR_STATUS] |= CR_STATUS_EH;
env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->regs[CR_EXCEPTION] &= ~(0x1F << 2);
env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2;
env->regs[CR_TLBMISC] |= CR_TLBMISC_DBL;
env->regs[R_PC] = cpu->exception_addr;
}
break;
case EXCP_TLBR:
case EXCP_TLBW:
case EXCP_TLBX:
qemu_log_mask(CPU_LOG_INT, "TLB PERM at pc=%x\n", env->regs[R_PC]);
env->regs[CR_ESTATUS] = env->regs[CR_STATUS];
env->regs[CR_STATUS] |= CR_STATUS_EH;
env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->regs[CR_EXCEPTION] &= ~(0x1F << 2);
env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2;
if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) {
env->regs[CR_TLBMISC] |= CR_TLBMISC_WR;
}
env->regs[R_EA] = env->regs[R_PC] + 4;
env->regs[R_PC] = cpu->exception_addr;
break;
case EXCP_SUPERA:
case EXCP_SUPERI:
case EXCP_SUPERD:
qemu_log_mask(CPU_LOG_INT, "SUPERVISOR exception at pc=%x\n",
env->regs[R_PC]);
if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) {
env->regs[CR_ESTATUS] = env->regs[CR_STATUS];
env->regs[R_EA] = env->regs[R_PC] + 4;
}
env->regs[CR_STATUS] |= CR_STATUS_EH;
env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->regs[CR_EXCEPTION] &= ~(0x1F << 2);
env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2;
env->regs[R_PC] = cpu->exception_addr;
break;
case EXCP_ILLEGAL:
case EXCP_TRAP:
qemu_log_mask(CPU_LOG_INT, "TRAP exception at pc=%x\n",
env->regs[R_PC]);
if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) {
env->regs[CR_ESTATUS] = env->regs[CR_STATUS];
env->regs[R_EA] = env->regs[R_PC] + 4;
}
env->regs[CR_STATUS] |= CR_STATUS_EH;
env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->regs[CR_EXCEPTION] &= ~(0x1F << 2);
env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2;
env->regs[R_PC] = cpu->exception_addr;
break;
case EXCP_BREAK:
qemu_log_mask(CPU_LOG_INT, "BREAK exception at pc=%x\n",
env->regs[R_PC]);
/* The semihosting instruction is "break 1". */
if (semihosting_enabled() &&
cpu_ldl_code(env, env->regs[R_PC]) == 0x003da07a) {
qemu_log_mask(CPU_LOG_INT, "Entering semihosting\n");
env->regs[R_PC] += 4;
do_nios2_semihosting(env);
break;
}
if ((env->regs[CR_STATUS] & CR_STATUS_EH) == 0) {
env->regs[CR_BSTATUS] = env->regs[CR_STATUS];
env->regs[R_BA] = env->regs[R_PC] + 4;
}
env->regs[CR_STATUS] |= CR_STATUS_EH;
env->regs[CR_STATUS] &= ~(CR_STATUS_PIE | CR_STATUS_U);
env->regs[CR_EXCEPTION] &= ~(0x1F << 2);
env->regs[CR_EXCEPTION] |= (cs->exception_index & 0x1F) << 2;
env->regs[R_PC] = cpu->exception_addr;
break;
default:
cpu_abort(cs, "unhandled exception type=%d\n",
cs->exception_index);
break;
}
}
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->regs[CR_BADADDR] = addr;
env->regs[CR_EXCEPTION] = EXCP_UNALIGN << 2;
helper_raise_exception(env, EXCP_UNALIGN);
}
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 = EXCP_TLBD;
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 = EXCP_SUPERA;
env->regs[CR_BADADDR] = address;
cpu_loop_exit_restore(cs, 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_TLBR :
access_type == MMU_DATA_STORE ? EXCP_TLBW : EXCP_TLBX);
}
if (probe) {
return false;
}
if (access_type == MMU_INST_FETCH) {
env->regs[CR_TLBMISC] &= ~CR_TLBMISC_D;
} else {
env->regs[CR_TLBMISC] |= CR_TLBMISC_D;
}
env->regs[CR_PTEADDR] &= CR_PTEADDR_PTBASE_MASK;
env->regs[CR_PTEADDR] |= (address >> 10) & CR_PTEADDR_VPN_MASK;
env->mmu.pteaddr_wr = env->regs[CR_PTEADDR];
cs->exception_index = excp;
env->regs[CR_BADADDR] = address;
cpu_loop_exit_restore(cs, retaddr);
}
#endif /* !CONFIG_USER_ONLY */