qemu-e2k/target-cris/mmu.c

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/*
* CRIS mmu emulation.
*
* Copyright (c) 2007 AXIS Communications AB
* Written by Edgar E. Iglesias.
*
* 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, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#ifndef CONFIG_USER_ONLY
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "config.h"
#include "cpu.h"
#include "mmu.h"
#include "exec-all.h"
static int cris_mmu_enabled(uint32_t rw_gc_cfg)
{
return (rw_gc_cfg & 12) != 0;
}
static int cris_mmu_segmented_addr(int seg, uint32_t rw_mm_cfg)
{
return (1 << seg) & rw_mm_cfg;
}
static uint32_t cris_mmu_translate_seg(CPUState *env, int seg)
{
uint32_t base;
int i;
if (seg < 8)
base = env->sregs[SFR_RW_MM_KBASE_LO];
else
base = env->sregs[SFR_RW_MM_KBASE_HI];
i = seg & 7;
base >>= i * 4;
base &= 15;
base <<= 28;
return base;
}
/* Used by the tlb decoder. */
#define EXTRACT_FIELD(src, start, end) \
(((src) >> start) & ((1 << (end - start + 1)) - 1))
static int cris_mmu_translate_page(struct cris_mmu_result_t *res,
CPUState *env, uint32_t vaddr,
int rw, int usermode)
{
unsigned int vpage;
unsigned int idx;
uint32_t lo, hi;
uint32_t vpn, pfn = 0, pid, fg, fv, fk, fw, fx;
int i, match = 0;
vpage = vaddr >> 13;
idx = vpage & 31;
vpage >>= 4;
/* We know the index which to check on each set.
Scan both I and D. */
for (i = 0; i < 4; i++)
{
lo = env->tlbsets[0][i][idx].lo;
hi = env->tlbsets[0][i][idx].hi;
vpn = EXTRACT_FIELD(hi, 13, 31);
pid = EXTRACT_FIELD(hi, 0, 7);
if (vpn == vpage
&& pid == env->pregs[SR_PID]) {
match = 1;
break;
}
}
if (match) {
pfn = EXTRACT_FIELD(lo, 13, 31);
fg = EXTRACT_FIELD(lo, 4, 4);
fv = EXTRACT_FIELD(lo, 3, 3);
fk = EXTRACT_FIELD(lo, 2, 2);
fw = EXTRACT_FIELD(lo, 1, 1);
fx = EXTRACT_FIELD(lo, 0, 0);
}
printf ("%s match=%d vaddr=%x vpage=%x vpn=%x pfn=%x pid=%x %x\n",
__func__, match,
vaddr, vpage,
vpn, pfn, pid, env->pregs[SR_PID]);
res->pfn = pfn;
return !match;
}
int cris_mmu_translate(struct cris_mmu_result_t *res,
CPUState *env, uint32_t vaddr,
int rw, int mmu_idx)
{
uint32_t phy = vaddr;
int seg;
int miss = 0;
int is_user = mmu_idx == MMU_USER_IDX;
if (!cris_mmu_enabled(env->sregs[SFR_RW_GC_CFG])) {
res->phy = vaddr;
return 0;
}
seg = vaddr >> 28;
if (cris_mmu_segmented_addr(seg, env->sregs[SFR_RW_MM_CFG]))
{
uint32_t base;
miss = 0;
base = cris_mmu_translate_seg(env, seg);
phy = base | (0x0fffffff & vaddr);
res->phy = phy;
}
else
{
miss = cris_mmu_translate_page(res, env, vaddr, rw, is_user);
if (!miss) {
phy &= 8191;
phy |= (res->pfn << 13);
res->phy = phy;
}
}
// printf ("miss=%d v=%x -> p=%x\n", miss, vaddr, phy);
return miss;
}
#endif