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CommitLineData
94cff60a
TS
1/*
2 * CRIS mmu emulation.
3 *
4 * Copyright (c) 2007 AXIS Communications AB
5 * Written by Edgar E. Iglesias.
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
8167ee88 18 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
94cff60a
TS
19 */
20
21#ifndef CONFIG_USER_ONLY
22
23#include <stdio.h>
24#include <string.h>
25#include <stdlib.h>
26
27#include "config.h"
28#include "cpu.h"
29#include "mmu.h"
30#include "exec-all.h"
31
d297f464
EI
32#ifdef DEBUG
33#define D(x) x
93fcfe39 34#define D_LOG(...) qemu_log(__VA__ARGS__)
d297f464 35#else
786c02f1 36#define D(x)
d12d51d5 37#define D_LOG(...) do { } while (0)
d297f464 38#endif
94cff60a 39
44cd42ee
EI
40void cris_mmu_init(CPUState *env)
41{
42 env->mmu_rand_lfsr = 0xcccc;
43}
44
45#define SR_POLYNOM 0x8805
46static inline unsigned int compute_polynom(unsigned int sr)
47{
48 unsigned int i;
49 unsigned int f;
50
51 f = 0;
52 for (i = 0; i < 16; i++)
53 f += ((SR_POLYNOM >> i) & 1) & ((sr >> i) & 1);
54
55 return f;
56}
57
ef29a70d 58static inline int cris_mmu_enabled(uint32_t rw_gc_cfg)
94cff60a
TS
59{
60 return (rw_gc_cfg & 12) != 0;
61}
62
ef29a70d 63static inline int cris_mmu_segmented_addr(int seg, uint32_t rw_mm_cfg)
94cff60a
TS
64{
65 return (1 << seg) & rw_mm_cfg;
66}
67
68static uint32_t cris_mmu_translate_seg(CPUState *env, int seg)
69{
70 uint32_t base;
71 int i;
72
73 if (seg < 8)
74 base = env->sregs[SFR_RW_MM_KBASE_LO];
75 else
76 base = env->sregs[SFR_RW_MM_KBASE_HI];
77
78 i = seg & 7;
79 base >>= i * 4;
80 base &= 15;
81
82 base <<= 28;
83 return base;
84}
85/* Used by the tlb decoder. */
86#define EXTRACT_FIELD(src, start, end) \
786c02f1
EI
87 (((src) >> start) & ((1 << (end - start + 1)) - 1))
88
89static inline void set_field(uint32_t *dst, unsigned int val,
90 unsigned int offset, unsigned int width)
91{
92 uint32_t mask;
93
94 mask = (1 << width) - 1;
95 mask <<= offset;
96 val <<= offset;
97
98 val &= mask;
786c02f1
EI
99 *dst &= ~(mask);
100 *dst |= val;
101}
94cff60a 102
d297f464 103#ifdef DEBUG
b41f7df0
EI
104static void dump_tlb(CPUState *env, int mmu)
105{
106 int set;
107 int idx;
108 uint32_t hi, lo, tlb_vpn, tlb_pfn;
109
110 for (set = 0; set < 4; set++) {
111 for (idx = 0; idx < 16; idx++) {
112 lo = env->tlbsets[mmu][set][idx].lo;
113 hi = env->tlbsets[mmu][set][idx].hi;
114 tlb_vpn = EXTRACT_FIELD(hi, 13, 31);
115 tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
116
117 printf ("TLB: [%d][%d] hi=%x lo=%x v=%x p=%x\n",
118 set, idx, hi, lo, tlb_vpn, tlb_pfn);
119 }
120 }
121}
d297f464 122#endif
b41f7df0
EI
123
124/* rw 0 = read, 1 = write, 2 = exec. */
2fa73ec8 125static int cris_mmu_translate_page(struct cris_mmu_result *res,
94cff60a
TS
126 CPUState *env, uint32_t vaddr,
127 int rw, int usermode)
128{
129 unsigned int vpage;
130 unsigned int idx;
b23761f9 131 uint32_t pid, lo, hi;
786c02f1
EI
132 uint32_t tlb_vpn, tlb_pfn = 0;
133 int tlb_pid, tlb_g, tlb_v, tlb_k, tlb_w, tlb_x;
134 int cfg_v, cfg_k, cfg_w, cfg_x;
b41f7df0 135 int set, match = 0;
786c02f1
EI
136 uint32_t r_cause;
137 uint32_t r_cfg;
138 int rwcause;
b41f7df0
EI
139 int mmu = 1; /* Data mmu is default. */
140 int vect_base;
786c02f1
EI
141
142 r_cause = env->sregs[SFR_R_MM_CAUSE];
143 r_cfg = env->sregs[SFR_RW_MM_CFG];
28de16da 144 pid = env->pregs[PR_PID] & 0xff;
b41f7df0
EI
145
146 switch (rw) {
147 case 2: rwcause = CRIS_MMU_ERR_EXEC; mmu = 0; break;
148 case 1: rwcause = CRIS_MMU_ERR_WRITE; break;
149 default:
150 case 0: rwcause = CRIS_MMU_ERR_READ; break;
151 }
152
153 /* I exception vectors 4 - 7, D 8 - 11. */
154 vect_base = (mmu + 1) * 4;
94cff60a
TS
155
156 vpage = vaddr >> 13;
94cff60a
TS
157
158 /* We know the index which to check on each set.
159 Scan both I and D. */
786c02f1 160#if 0
b41f7df0
EI
161 for (set = 0; set < 4; set++) {
162 for (idx = 0; idx < 16; idx++) {
163 lo = env->tlbsets[mmu][set][idx].lo;
164 hi = env->tlbsets[mmu][set][idx].hi;
786c02f1
EI
165 tlb_vpn = EXTRACT_FIELD(hi, 13, 31);
166 tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
167
168 printf ("TLB: [%d][%d] hi=%x lo=%x v=%x p=%x\n",
b41f7df0 169 set, idx, hi, lo, tlb_vpn, tlb_pfn);
786c02f1
EI
170 }
171 }
172#endif
b41f7df0
EI
173
174 idx = vpage & 15;
175 for (set = 0; set < 4; set++)
94cff60a 176 {
b41f7df0
EI
177 lo = env->tlbsets[mmu][set][idx].lo;
178 hi = env->tlbsets[mmu][set][idx].hi;
94cff60a 179
b23761f9 180 tlb_vpn = hi >> 13;
44cd42ee 181 tlb_pid = EXTRACT_FIELD(hi, 0, 7);
44cd42ee 182 tlb_g = EXTRACT_FIELD(lo, 4, 4);
94cff60a 183
d12d51d5
AL
184 D_LOG("TLB[%d][%d][%d] v=%x vpage=%x lo=%x hi=%x\n",
185 mmu, set, idx, tlb_vpn, vpage, lo, hi);
b23761f9 186 if ((tlb_g || (tlb_pid == pid))
44cd42ee 187 && tlb_vpn == vpage) {
94cff60a
TS
188 match = 1;
189 break;
190 }
191 }
192
b41f7df0 193 res->bf_vec = vect_base;
94cff60a 194 if (match) {
786c02f1
EI
195 cfg_w = EXTRACT_FIELD(r_cfg, 19, 19);
196 cfg_k = EXTRACT_FIELD(r_cfg, 18, 18);
197 cfg_x = EXTRACT_FIELD(r_cfg, 17, 17);
198 cfg_v = EXTRACT_FIELD(r_cfg, 16, 16);
199
786c02f1 200 tlb_pfn = EXTRACT_FIELD(lo, 13, 31);
786c02f1
EI
201 tlb_v = EXTRACT_FIELD(lo, 3, 3);
202 tlb_k = EXTRACT_FIELD(lo, 2, 2);
203 tlb_w = EXTRACT_FIELD(lo, 1, 1);
204 tlb_x = EXTRACT_FIELD(lo, 0, 0);
205
206 /*
207 set_exception_vector(0x04, i_mmu_refill);
208 set_exception_vector(0x05, i_mmu_invalid);
209 set_exception_vector(0x06, i_mmu_access);
210 set_exception_vector(0x07, i_mmu_execute);
211 set_exception_vector(0x08, d_mmu_refill);
212 set_exception_vector(0x09, d_mmu_invalid);
213 set_exception_vector(0x0a, d_mmu_access);
214 set_exception_vector(0x0b, d_mmu_write);
215 */
44cd42ee 216 if (cfg_k && tlb_k && usermode) {
ef29a70d
EI
217 D(printf ("tlb: kernel protected %x lo=%x pc=%x\n",
218 vaddr, lo, env->pc));
219 match = 0;
220 res->bf_vec = vect_base + 2;
b41f7df0 221 } else if (rw == 1 && cfg_w && !tlb_w) {
ef29a70d
EI
222 D(printf ("tlb: write protected %x lo=%x pc=%x\n",
223 vaddr, lo, env->pc));
224 match = 0;
225 /* write accesses never go through the I mmu. */
226 res->bf_vec = vect_base + 3;
227 } else if (rw == 2 && cfg_x && !tlb_x) {
228 D(printf ("tlb: exec protected %x lo=%x pc=%x\n",
229 vaddr, lo, env->pc));
786c02f1 230 match = 0;
b41f7df0
EI
231 res->bf_vec = vect_base + 3;
232 } else if (cfg_v && !tlb_v) {
233 D(printf ("tlb: invalid %x\n", vaddr));
786c02f1 234 match = 0;
b41f7df0 235 res->bf_vec = vect_base + 1;
786c02f1 236 }
786c02f1 237
b41f7df0
EI
238 res->prot = 0;
239 if (match) {
240 res->prot |= PAGE_READ;
241 if (tlb_w)
242 res->prot |= PAGE_WRITE;
243 if (tlb_x)
244 res->prot |= PAGE_EXEC;
245 }
246 else
247 D(dump_tlb(env, mmu));
44cd42ee
EI
248 } else {
249 /* If refill, provide a randomized set. */
250 set = env->mmu_rand_lfsr & 3;
786c02f1
EI
251 }
252
253 if (!match) {
44cd42ee
EI
254 unsigned int f;
255
256 /* Update lfsr at every fault. */
257 f = compute_polynom(env->mmu_rand_lfsr);
258 env->mmu_rand_lfsr >>= 1;
259 env->mmu_rand_lfsr |= (f << 15);
260 env->mmu_rand_lfsr &= 0xffff;
261
262 /* Compute index. */
b41f7df0 263 idx = vpage & 15;
b41f7df0
EI
264
265 /* Update RW_MM_TLB_SEL. */
266 env->sregs[SFR_RW_MM_TLB_SEL] = 0;
267 set_field(&env->sregs[SFR_RW_MM_TLB_SEL], idx, 0, 4);
44cd42ee 268 set_field(&env->sregs[SFR_RW_MM_TLB_SEL], set, 4, 2);
b41f7df0
EI
269
270 /* Update RW_MM_CAUSE. */
271 set_field(&r_cause, rwcause, 8, 2);
786c02f1 272 set_field(&r_cause, vpage, 13, 19);
28de16da 273 set_field(&r_cause, pid, 0, 8);
786c02f1 274 env->sregs[SFR_R_MM_CAUSE] = r_cause;
b41f7df0 275 D(printf("refill vaddr=%x pc=%x\n", vaddr, env->pc));
94cff60a 276 }
b41f7df0 277
b41f7df0
EI
278 D(printf ("%s rw=%d mtch=%d pc=%x va=%x vpn=%x tlbvpn=%x pfn=%x pid=%x"
279 " %x cause=%x sel=%x sp=%x %x %x\n",
280 __func__, rw, match, env->pc,
786c02f1
EI
281 vaddr, vpage,
282 tlb_vpn, tlb_pfn, tlb_pid,
28de16da 283 pid,
786c02f1
EI
284 r_cause,
285 env->sregs[SFR_RW_MM_TLB_SEL],
b41f7df0 286 env->regs[R_SP], env->pregs[PR_USP], env->ksp));
786c02f1 287
bf91ada5 288 res->phy = tlb_pfn << TARGET_PAGE_BITS;
94cff60a
TS
289 return !match;
290}
291
cf1d97f0 292void cris_mmu_flush_pid(CPUState *env, uint32_t pid)
786c02f1 293{
cf1d97f0
EI
294 target_ulong vaddr;
295 unsigned int idx;
296 uint32_t lo, hi;
297 uint32_t tlb_vpn;
80e1b265 298 int tlb_pid, tlb_g, tlb_v;
cf1d97f0
EI
299 unsigned int set;
300 unsigned int mmu;
301
302 pid &= 0xff;
303 for (mmu = 0; mmu < 2; mmu++) {
304 for (set = 0; set < 4; set++)
305 {
306 for (idx = 0; idx < 16; idx++) {
307 lo = env->tlbsets[mmu][set][idx].lo;
308 hi = env->tlbsets[mmu][set][idx].hi;
309
310 tlb_vpn = EXTRACT_FIELD(hi, 13, 31);
311 tlb_pid = EXTRACT_FIELD(hi, 0, 7);
312 tlb_g = EXTRACT_FIELD(lo, 4, 4);
313 tlb_v = EXTRACT_FIELD(lo, 3, 3);
cf1d97f0 314
80e1b265 315 if (tlb_v && !tlb_g && (tlb_pid == pid)) {
cf1d97f0 316 vaddr = tlb_vpn << TARGET_PAGE_BITS;
d12d51d5
AL
317 D_LOG("flush pid=%x vaddr=%x\n",
318 pid, vaddr);
cf1d97f0
EI
319 tlb_flush_page(env, vaddr);
320 }
321 }
322 }
323 }
786c02f1
EI
324}
325
2fa73ec8 326int cris_mmu_translate(struct cris_mmu_result *res,
94cff60a 327 CPUState *env, uint32_t vaddr,
6ebbf390 328 int rw, int mmu_idx)
94cff60a
TS
329{
330 uint32_t phy = vaddr;
331 int seg;
332 int miss = 0;
786c02f1 333 int is_user = mmu_idx == MMU_USER_IDX;
b41f7df0
EI
334 uint32_t old_srs;
335
336 old_srs= env->pregs[PR_SRS];
337
338 /* rw == 2 means exec, map the access to the insn mmu. */
339 env->pregs[PR_SRS] = rw == 2 ? 1 : 2;
94cff60a
TS
340
341 if (!cris_mmu_enabled(env->sregs[SFR_RW_GC_CFG])) {
342 res->phy = vaddr;
b23761f9 343 res->prot = PAGE_BITS;
b41f7df0 344 goto done;
94cff60a
TS
345 }
346
347 seg = vaddr >> 28;
218951ef 348 if (!is_user && cris_mmu_segmented_addr(seg, env->sregs[SFR_RW_MM_CFG]))
94cff60a
TS
349 {
350 uint32_t base;
351
352 miss = 0;
353 base = cris_mmu_translate_seg(env, seg);
354 phy = base | (0x0fffffff & vaddr);
355 res->phy = phy;
b23761f9 356 res->prot = PAGE_BITS;
94cff60a
TS
357 }
358 else
94cff60a 359 miss = cris_mmu_translate_page(res, env, vaddr, rw, is_user);
b41f7df0
EI
360 done:
361 env->pregs[PR_SRS] = old_srs;
94cff60a
TS
362 return miss;
363}
364#endif