qemu-e2k/target-cris/mmu.c
edgar_igl 786c02f1ac Model more parts of the ETRAX mmu (still alot missing).
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@4056 c046a42c-6fe2-441c-8c8c-71466251a162
2008-03-14 01:08:09 +00:00

268 lines
6.3 KiB
C

/*
* 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"
#define D(x)
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 inline void set_field(uint32_t *dst, unsigned int val,
unsigned int offset, unsigned int width)
{
uint32_t mask;
mask = (1 << width) - 1;
mask <<= offset;
val <<= offset;
val &= mask;
D(printf ("val=%x mask=%x dst=%x\n", val, mask, *dst));
*dst &= ~(mask);
*dst |= val;
}
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 tlb_vpn, tlb_pfn = 0;
int tlb_pid, tlb_g, tlb_v, tlb_k, tlb_w, tlb_x;
int cfg_v, cfg_k, cfg_w, cfg_x;
int i, match = 0;
uint32_t r_cause;
uint32_t r_cfg;
int rwcause;
int update_sel = 0;
r_cause = env->sregs[SFR_R_MM_CAUSE];
r_cfg = env->sregs[SFR_RW_MM_CFG];
rwcause = rw ? CRIS_MMU_ERR_WRITE : CRIS_MMU_ERR_READ;
vpage = vaddr >> 13;
idx = vpage & 15;
/* We know the index which to check on each set.
Scan both I and D. */
#if 0
for (i = 0; i < 4; i++) {
int j;
for (j = 0; j < 16; j++) {
lo = env->tlbsets[1][i][j].lo;
hi = env->tlbsets[1][i][j].hi;
tlb_vpn = EXTRACT_FIELD(hi, 13, 31);
tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
printf ("TLB: [%d][%d] hi=%x lo=%x v=%x p=%x\n",
i, j, hi, lo, tlb_vpn, tlb_pfn);
}
}
#endif
for (i = 0; i < 4; i++)
{
lo = env->tlbsets[1][i][idx].lo;
hi = env->tlbsets[1][i][idx].hi;
tlb_vpn = EXTRACT_FIELD(hi, 13, 31);
tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
D(printf ("TLB[%d][%d] tlbv=%x vpage=%x -> pfn=%x\n",
i, idx, tlb_vpn, vpage, tlb_pfn));
if (tlb_vpn == vpage) {
match = 1;
break;
}
}
if (match) {
cfg_w = EXTRACT_FIELD(r_cfg, 19, 19);
cfg_k = EXTRACT_FIELD(r_cfg, 18, 18);
cfg_x = EXTRACT_FIELD(r_cfg, 17, 17);
cfg_v = EXTRACT_FIELD(r_cfg, 16, 16);
tlb_pid = EXTRACT_FIELD(hi, 0, 7);
tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
tlb_g = EXTRACT_FIELD(lo, 4, 4);
tlb_v = EXTRACT_FIELD(lo, 3, 3);
tlb_k = EXTRACT_FIELD(lo, 2, 2);
tlb_w = EXTRACT_FIELD(lo, 1, 1);
tlb_x = EXTRACT_FIELD(lo, 0, 0);
/*
set_exception_vector(0x04, i_mmu_refill);
set_exception_vector(0x05, i_mmu_invalid);
set_exception_vector(0x06, i_mmu_access);
set_exception_vector(0x07, i_mmu_execute);
set_exception_vector(0x08, d_mmu_refill);
set_exception_vector(0x09, d_mmu_invalid);
set_exception_vector(0x0a, d_mmu_access);
set_exception_vector(0x0b, d_mmu_write);
*/
if (cfg_v && !tlb_v) {
printf ("tlb: invalid\n");
set_field(&r_cause, rwcause, 8, 9);
match = 0;
res->bf_vec = 0x9;
update_sel = 1;
}
else if (!tlb_g
&& tlb_pid != 0xff
&& tlb_pid != env->pregs[PR_PID]
&& cfg_w && !tlb_w) {
printf ("tlb: wrong pid\n");
match = 0;
res->bf_vec = 0xa;
}
else if (rw && cfg_w && !tlb_w) {
printf ("tlb: write protected\n");
match = 0;
res->bf_vec = 0xb;
}
} else
update_sel = 1;
if (update_sel) {
/* miss. */
env->sregs[SFR_RW_MM_TLB_SEL] = 0;
D(printf ("tlb: miss %x vp=%x\n",
env->sregs[SFR_RW_MM_TLB_SEL], vpage & 15));
set_field(&env->sregs[SFR_RW_MM_TLB_SEL], vpage & 15, 0, 4);
set_field(&env->sregs[SFR_RW_MM_TLB_SEL], 0, 4, 5);
res->bf_vec = 0x8;
}
if (!match) {
set_field(&r_cause, rwcause, 8, 9);
set_field(&r_cause, vpage, 13, 19);
set_field(&r_cause, env->pregs[PR_PID], 0, 8);
env->sregs[SFR_R_MM_CAUSE] = r_cause;
}
D(printf ("%s mtch=%d pc=%x va=%x vpn=%x tlbvpn=%x pfn=%x pid=%x"
" %x cause=%x sel=%x r13=%x\n",
__func__, match, env->pc,
vaddr, vpage,
tlb_vpn, tlb_pfn, tlb_pid,
env->pregs[PR_PID],
r_cause,
env->sregs[SFR_RW_MM_TLB_SEL],
env->regs[13]));
res->pfn = tlb_pfn;
return !match;
}
/* Give us the vaddr corresponding to the latest TLB update. */
target_ulong cris_mmu_tlb_latest_update(CPUState *env, uint32_t new_lo)
{
uint32_t sel = env->sregs[SFR_RW_MM_TLB_SEL];
uint32_t vaddr;
uint32_t hi;
int set;
int idx;
idx = EXTRACT_FIELD(sel, 0, 4);
set = EXTRACT_FIELD(sel, 4, 5);
hi = env->tlbsets[1][set][idx].hi;
vaddr = EXTRACT_FIELD(hi, 13, 31);
return vaddr << TARGET_PAGE_BITS;
}
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;
}
}
D(printf ("miss=%d v=%x -> p=%x\n", miss, vaddr, phy));
return miss;
}
#endif