]> git.proxmox.com Git - mirror_qemu.git/blame - target/nios2/mmu.c
slirp: Make RA build more flexible
[mirror_qemu.git] / target / nios2 / mmu.c
CommitLineData
032c76bc
CW
1/*
2 * Altera Nios II MMU emulation for qemu.
3 *
4 * Copyright (C) 2012 Chris Wulff <crwulff@gmail.com>
5 *
6 * This library is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU Lesser General Public
8 * License as published by the Free Software Foundation; either
9 * version 2.1 of the License, or (at your option) any later version.
10 *
11 * This library is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 * Lesser General Public License for more details.
15 *
16 * You should have received a copy of the GNU Lesser General Public
17 * License along with this library; if not, see
18 * <http://www.gnu.org/licenses/lgpl-2.1.html>
19 */
20
21#include "qemu/osdep.h"
22#include "qemu-common.h"
23#include "cpu.h"
24#include "exec/exec-all.h"
25#include "mmu.h"
26
27#if !defined(CONFIG_USER_ONLY)
28
29/* Define this to enable MMU debug messages */
30/* #define DEBUG_MMU */
31
32#ifdef DEBUG_MMU
33#define MMU_LOG(x) x
34#else
35#define MMU_LOG(x)
36#endif
37
38void tlb_fill(CPUState *cs, target_ulong addr, MMUAccessType access_type,
39 int mmu_idx, uintptr_t retaddr)
40{
41 int ret;
42
43 ret = nios2_cpu_handle_mmu_fault(cs, addr, access_type, mmu_idx);
44 if (unlikely(ret)) {
45 if (retaddr) {
46 /* now we have a real cpu fault */
47 cpu_restore_state(cs, retaddr);
48 }
49 cpu_loop_exit(cs);
50 }
51}
52
53void mmu_read_debug(CPUNios2State *env, uint32_t rn)
54{
55 switch (rn) {
56 case CR_TLBACC:
57 MMU_LOG(qemu_log("TLBACC READ %08X\n", env->regs[rn]));
58 break;
59
60 case CR_TLBMISC:
61 MMU_LOG(qemu_log("TLBMISC READ %08X\n", env->regs[rn]));
62 break;
63
64 case CR_PTEADDR:
65 MMU_LOG(qemu_log("PTEADDR READ %08X\n", env->regs[rn]));
66 break;
67
68 default:
69 break;
70 }
71}
72
73/* rw - 0 = read, 1 = write, 2 = fetch. */
74unsigned int mmu_translate(CPUNios2State *env,
75 Nios2MMULookup *lu,
76 target_ulong vaddr, int rw, int mmu_idx)
77{
78 Nios2CPU *cpu = nios2_env_get_cpu(env);
79 int pid = (env->mmu.tlbmisc_wr & CR_TLBMISC_PID_MASK) >> 4;
80 int vpn = vaddr >> 12;
81
82 MMU_LOG(qemu_log("mmu_translate vaddr %08X, pid %08X, vpn %08X\n",
83 vaddr, pid, vpn));
84
85 int way;
86 for (way = 0; way < cpu->tlb_num_ways; way++) {
87
88 Nios2TLBEntry *entry =
89 &env->mmu.tlb[(way * cpu->tlb_num_ways) +
90 (vpn & env->mmu.tlb_entry_mask)];
91
92 MMU_LOG(qemu_log("TLB[%d] TAG %08X, VPN %08X\n",
93 (way * cpu->tlb_num_ways) +
94 (vpn & env->mmu.tlb_entry_mask),
95 entry->tag, (entry->tag >> 12)));
96
97 if (((entry->tag >> 12) != vpn) ||
98 (((entry->tag & (1 << 11)) == 0) &&
99 ((entry->tag & ((1 << cpu->pid_num_bits) - 1)) != pid))) {
100 continue;
101 }
102 lu->vaddr = vaddr & TARGET_PAGE_MASK;
103 lu->paddr = (entry->data & CR_TLBACC_PFN_MASK) << TARGET_PAGE_BITS;
104 lu->prot = ((entry->data & CR_TLBACC_R) ? PAGE_READ : 0) |
105 ((entry->data & CR_TLBACC_W) ? PAGE_WRITE : 0) |
106 ((entry->data & CR_TLBACC_X) ? PAGE_EXEC : 0);
107
108 MMU_LOG(qemu_log("HIT TLB[%d] %08X %08X %08X\n",
109 (way * cpu->tlb_num_ways) +
110 (vpn & env->mmu.tlb_entry_mask),
111 lu->vaddr, lu->paddr, lu->prot));
112 return 1;
113 }
114 return 0;
115}
116
117static void mmu_flush_pid(CPUNios2State *env, uint32_t pid)
118{
119 CPUState *cs = ENV_GET_CPU(env);
120 Nios2CPU *cpu = nios2_env_get_cpu(env);
121 int idx;
122 MMU_LOG(qemu_log("TLB Flush PID %d\n", pid));
123
124 for (idx = 0; idx < cpu->tlb_num_entries; idx++) {
125 Nios2TLBEntry *entry = &env->mmu.tlb[idx];
126
127 MMU_LOG(qemu_log("TLB[%d] => %08X %08X\n",
128 idx, entry->tag, entry->data));
129
130 if ((entry->tag & (1 << 10)) && (!(entry->tag & (1 << 11))) &&
131 ((entry->tag & ((1 << cpu->pid_num_bits) - 1)) == pid)) {
132 uint32_t vaddr = entry->tag & TARGET_PAGE_MASK;
133
134 MMU_LOG(qemu_log("TLB Flush Page %08X\n", vaddr));
135
136 tlb_flush_page(cs, vaddr);
137 }
138 }
139}
140
141void mmu_write(CPUNios2State *env, uint32_t rn, uint32_t v)
142{
143 CPUState *cs = ENV_GET_CPU(env);
144 Nios2CPU *cpu = nios2_env_get_cpu(env);
145
146 MMU_LOG(qemu_log("mmu_write %08X = %08X\n", rn, v));
147
148 switch (rn) {
149 case CR_TLBACC:
150 MMU_LOG(qemu_log("TLBACC: IG %02X, FLAGS %c%c%c%c%c, PFN %05X\n",
151 v >> CR_TLBACC_IGN_SHIFT,
152 (v & CR_TLBACC_C) ? 'C' : '.',
153 (v & CR_TLBACC_R) ? 'R' : '.',
154 (v & CR_TLBACC_W) ? 'W' : '.',
155 (v & CR_TLBACC_X) ? 'X' : '.',
156 (v & CR_TLBACC_G) ? 'G' : '.',
157 v & CR_TLBACC_PFN_MASK));
158
159 /* if tlbmisc.WE == 1 then trigger a TLB write on writes to TLBACC */
160 if (env->regs[CR_TLBMISC] & CR_TLBMISC_WR) {
161 int way = (env->regs[CR_TLBMISC] >> CR_TLBMISC_WAY_SHIFT);
162 int vpn = (env->mmu.pteaddr_wr & CR_PTEADDR_VPN_MASK) >> 2;
163 int pid = (env->mmu.tlbmisc_wr & CR_TLBMISC_PID_MASK) >> 4;
164 int g = (v & CR_TLBACC_G) ? 1 : 0;
165 int valid = ((vpn & CR_TLBACC_PFN_MASK) < 0xC0000) ? 1 : 0;
166 Nios2TLBEntry *entry =
167 &env->mmu.tlb[(way * cpu->tlb_num_ways) +
168 (vpn & env->mmu.tlb_entry_mask)];
169 uint32_t newTag = (vpn << 12) | (g << 11) | (valid << 10) | pid;
170 uint32_t newData = v & (CR_TLBACC_C | CR_TLBACC_R | CR_TLBACC_W |
171 CR_TLBACC_X | CR_TLBACC_PFN_MASK);
172
173 if ((entry->tag != newTag) || (entry->data != newData)) {
174 if (entry->tag & (1 << 10)) {
175 /* Flush existing entry */
176 MMU_LOG(qemu_log("TLB Flush Page (OLD) %08X\n",
177 entry->tag & TARGET_PAGE_MASK));
178 tlb_flush_page(cs, entry->tag & TARGET_PAGE_MASK);
179 }
180 entry->tag = newTag;
181 entry->data = newData;
182 MMU_LOG(qemu_log("TLB[%d] = %08X %08X\n",
183 (way * cpu->tlb_num_ways) +
184 (vpn & env->mmu.tlb_entry_mask),
185 entry->tag, entry->data));
186 }
187 /* Auto-increment tlbmisc.WAY */
188 env->regs[CR_TLBMISC] =
189 (env->regs[CR_TLBMISC] & ~CR_TLBMISC_WAY_MASK) |
190 (((way + 1) & (cpu->tlb_num_ways - 1)) <<
191 CR_TLBMISC_WAY_SHIFT);
192 }
193
194 /* Writes to TLBACC don't change the read-back value */
195 env->mmu.tlbacc_wr = v;
196 break;
197
198 case CR_TLBMISC:
199 MMU_LOG(qemu_log("TLBMISC: WAY %X, FLAGS %c%c%c%c%c%c, PID %04X\n",
200 v >> CR_TLBMISC_WAY_SHIFT,
201 (v & CR_TLBMISC_RD) ? 'R' : '.',
202 (v & CR_TLBMISC_WR) ? 'W' : '.',
203 (v & CR_TLBMISC_DBL) ? '2' : '.',
204 (v & CR_TLBMISC_BAD) ? 'B' : '.',
205 (v & CR_TLBMISC_PERM) ? 'P' : '.',
206 (v & CR_TLBMISC_D) ? 'D' : '.',
207 (v & CR_TLBMISC_PID_MASK) >> 4));
208
209 if ((v & CR_TLBMISC_PID_MASK) !=
210 (env->mmu.tlbmisc_wr & CR_TLBMISC_PID_MASK)) {
211 mmu_flush_pid(env, (env->mmu.tlbmisc_wr & CR_TLBMISC_PID_MASK) >>
212 CR_TLBMISC_PID_SHIFT);
213 }
214 /* if tlbmisc.RD == 1 then trigger a TLB read on writes to TLBMISC */
215 if (v & CR_TLBMISC_RD) {
216 int way = (v >> CR_TLBMISC_WAY_SHIFT);
217 int vpn = (env->mmu.pteaddr_wr & CR_PTEADDR_VPN_MASK) >> 2;
218 Nios2TLBEntry *entry =
219 &env->mmu.tlb[(way * cpu->tlb_num_ways) +
220 (vpn & env->mmu.tlb_entry_mask)];
221
222 env->regs[CR_TLBACC] &= CR_TLBACC_IGN_MASK;
223 env->regs[CR_TLBACC] |= entry->data;
224 env->regs[CR_TLBACC] |= (entry->tag & (1 << 11)) ? CR_TLBACC_G : 0;
225 env->regs[CR_TLBMISC] =
226 (v & ~CR_TLBMISC_PID_MASK) |
227 ((entry->tag & ((1 << cpu->pid_num_bits) - 1)) <<
228 CR_TLBMISC_PID_SHIFT);
229 env->regs[CR_PTEADDR] &= ~CR_PTEADDR_VPN_MASK;
230 env->regs[CR_PTEADDR] |= (entry->tag >> 12) << CR_PTEADDR_VPN_SHIFT;
231 MMU_LOG(qemu_log("TLB READ way %d, vpn %05X, tag %08X, data %08X, "
232 "tlbacc %08X, tlbmisc %08X, pteaddr %08X\n",
233 way, vpn, entry->tag, entry->data,
234 env->regs[CR_TLBACC], env->regs[CR_TLBMISC],
235 env->regs[CR_PTEADDR]));
236 } else {
237 env->regs[CR_TLBMISC] = v;
238 }
239
240 env->mmu.tlbmisc_wr = v;
241 break;
242
243 case CR_PTEADDR:
244 MMU_LOG(qemu_log("PTEADDR: PTBASE %03X, VPN %05X\n",
245 v >> CR_PTEADDR_PTBASE_SHIFT,
246 (v & CR_PTEADDR_VPN_MASK) >> CR_PTEADDR_VPN_SHIFT));
247
248 /* Writes to PTEADDR don't change the read-back VPN value */
249 env->regs[CR_PTEADDR] = (v & ~CR_PTEADDR_VPN_MASK) |
250 (env->regs[CR_PTEADDR] & CR_PTEADDR_VPN_MASK);
251 env->mmu.pteaddr_wr = v;
252 break;
253
254 default:
255 break;
256 }
257}
258
259void mmu_init(CPUNios2State *env)
260{
261 Nios2CPU *cpu = nios2_env_get_cpu(env);
262 Nios2MMU *mmu = &env->mmu;
263
264 MMU_LOG(qemu_log("mmu_init\n"));
265
266 mmu->tlb_entry_mask = (cpu->tlb_num_entries / cpu->tlb_num_ways) - 1;
267 mmu->tlb = g_new0(Nios2TLBEntry, cpu->tlb_num_entries);
268}
269
270void dump_mmu(FILE *f, fprintf_function cpu_fprintf, CPUNios2State *env)
271{
272 Nios2CPU *cpu = nios2_env_get_cpu(env);
273 int i;
274
275 cpu_fprintf(f, "MMU: ways %d, entries %d, pid bits %d\n",
276 cpu->tlb_num_ways, cpu->tlb_num_entries,
277 cpu->pid_num_bits);
278
279 for (i = 0; i < cpu->tlb_num_entries; i++) {
280 Nios2TLBEntry *entry = &env->mmu.tlb[i];
281 cpu_fprintf(f, "TLB[%d] = %08X %08X %c VPN %05X "
282 "PID %02X %c PFN %05X %c%c%c%c\n",
283 i, entry->tag, entry->data,
284 (entry->tag & (1 << 10)) ? 'V' : '-',
285 entry->tag >> 12,
286 entry->tag & ((1 << cpu->pid_num_bits) - 1),
287 (entry->tag & (1 << 11)) ? 'G' : '-',
288 entry->data & CR_TLBACC_PFN_MASK,
289 (entry->data & CR_TLBACC_C) ? 'C' : '-',
290 (entry->data & CR_TLBACC_R) ? 'R' : '-',
291 (entry->data & CR_TLBACC_W) ? 'W' : '-',
292 (entry->data & CR_TLBACC_X) ? 'X' : '-');
293 }
294}
295
296#endif /* !CONFIG_USER_ONLY */