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[/] [eco32/] [trunk/] [sim/] [mmu.c] - Blame information for rev 203

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/*
 * mmu.c -- MMU simulation
 */
 
 
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <setjmp.h>
 
#include "common.h"
#include "console.h"
#include "error.h"
#include "except.h"
#include "cpu.h"
#include "mmu.h"
#include "memory.h"
 
 
static Bool debugUse = false;
static Bool debugWrite = false;
 
 
static TLB_Entry tlb[TLB_SIZE];
static Word tlbIndex;
static Word tlbEntryHi;
static Word tlbEntryLo;
static Word mmuBadAddr;
static Word mmuBadAccs;
 
static int randomIndex;
 
 
static void updateRandomIndex(void) {
  if (randomIndex == TLB_FIXED) {
    randomIndex = TLB_MASK;
  } else {
    randomIndex--;
  }
}
 
 
static int assoc(Word page) {
  int n, i;
 
  n = -1;
  for (i = 0; i < TLB_SIZE; i++) {
    if (tlb[i].page == page) {
      n = i;
    }
  }
  return n;
}
 
 
static Word v2p(Word vAddr, Bool userMode, Bool writing, int accsWidth) {
  Word pAddr;
  Word page, offset;
  int index;
 
  if (debugUse) {
    cPrintf("**** vAddr = 0x%08X", vAddr);
  }
  if ((vAddr & 0x80000000) != 0 && userMode) {
    /* trying to access a privileged address from user mode */
    mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) | accsWidth;
    mmuBadAddr = vAddr;
    throwException(EXC_PRV_ADDRESS);
  }
  updateRandomIndex();
  if ((vAddr & 0xC0000000) == 0xC0000000) {
    /* unmapped address space */
    /* simulate delay introduced by assoc when using mapped
       addresses but not experienced with unmapped addresses */
    assoc(0);
    pAddr = vAddr & ~0xC0000000;
  } else {
    /* mapped address space */
    page = vAddr & PAGE_MASK;
    offset = vAddr & OFFSET_MASK;
    index = assoc(page);
    if (index == -1) {
      /* TLB miss exception */
      mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) | accsWidth;
      mmuBadAddr = vAddr;
      tlbEntryHi = page;
      throwException(EXC_TLB_MISS);
    }
    if (!tlb[index].valid) {
      /* TLB invalid exception */
      mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) | accsWidth;
      mmuBadAddr = vAddr;
      tlbEntryHi = page;
      throwException(EXC_TLB_INVALID);
    }
    if (!tlb[index].write && writing) {
      /* TLB write exception */
      mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) | accsWidth;
      mmuBadAddr = vAddr;
      tlbEntryHi = page;
      throwException(EXC_TLB_WRITE);
    }
    pAddr = tlb[index].frame | offset;
  }
  if (debugUse) {
    cPrintf(", pAddr = 0x%08X ****\n", pAddr);
  }
  return pAddr;
}
 
 
Word mmuReadWord(Word vAddr, Bool userMode) {
  if ((vAddr & 3) != 0) {
    /* throw illegal address exception */
    mmuBadAccs = MMU_ACCS_READ | MMU_ACCS_WORD;
    mmuBadAddr = vAddr;
    throwException(EXC_ILL_ADDRESS);
  }
  return memoryReadWord(v2p(vAddr, userMode, false, MMU_ACCS_WORD));
}
 
 
Half mmuReadHalf(Word vAddr, Bool userMode) {
  if ((vAddr & 1) != 0) {
    /* throw illegal address exception */
    mmuBadAccs = MMU_ACCS_READ | MMU_ACCS_HALF;
    mmuBadAddr = vAddr;
    throwException(EXC_ILL_ADDRESS);
  }
  return memoryReadHalf(v2p(vAddr, userMode, false, MMU_ACCS_HALF));
}
 
 
Byte mmuReadByte(Word vAddr, Bool userMode) {
  return memoryReadByte(v2p(vAddr, userMode, false, MMU_ACCS_BYTE));
}
 
 
void mmuWriteWord(Word vAddr, Word data, Bool userMode) {
  if ((vAddr & 3) != 0) {
    /* throw illegal address exception */
    mmuBadAccs = MMU_ACCS_WRITE | MMU_ACCS_WORD;
    mmuBadAddr = vAddr;
    throwException(EXC_ILL_ADDRESS);
  }
  memoryWriteWord(v2p(vAddr, userMode, true, MMU_ACCS_WORD), data);
}
 
 
void mmuWriteHalf(Word vAddr, Half data, Bool userMode) {
  if ((vAddr & 1) != 0) {
    /* throw illegal address exception */
    mmuBadAccs = MMU_ACCS_WRITE | MMU_ACCS_HALF;
    mmuBadAddr = vAddr;
    throwException(EXC_ILL_ADDRESS);
  }
  memoryWriteHalf(v2p(vAddr, userMode, true, MMU_ACCS_HALF), data);
}
 
 
void mmuWriteByte(Word vAddr, Byte data, Bool userMode) {
  memoryWriteByte(v2p(vAddr, userMode, true, MMU_ACCS_BYTE), data);
}
 
 
Word mmuGetIndex(void) {
  return tlbIndex;
}
 
 
void mmuSetIndex(Word value) {
  tlbIndex = value & TLB_MASK;
}
 
 
Word mmuGetEntryHi(void) {
  return tlbEntryHi;
}
 
 
void mmuSetEntryHi(Word value) {
  tlbEntryHi = value & PAGE_MASK;
}
 
 
Word mmuGetEntryLo(void) {
  return tlbEntryLo;
}
 
 
void mmuSetEntryLo(Word value) {
  tlbEntryLo = value & (PAGE_MASK | TLB_WRITE | TLB_VALID);
}
 
 
Word mmuGetBadAddr(void) {
  return mmuBadAddr;
}
 
 
void mmuSetBadAddr(Word value) {
  mmuBadAddr = value;
}
 
 
Word mmuGetBadAccs(void) {
  return mmuBadAccs;
}
 
 
void mmuSetBadAccs(Word value) {
  mmuBadAccs = value;
}
 
 
void mmuTbs(void) {
  int index;
 
  index = assoc(tlbEntryHi & PAGE_MASK);
  if (index == -1) {
    tlbIndex = 0x80000000;
  } else {
    tlbIndex = index;
  }
}
 
 
void mmuTbwr(void) {
  int index;
 
  /* choose a random index, but don't touch fixed entries */
  index = randomIndex;
  tlb[index].page = tlbEntryHi & PAGE_MASK;
  tlb[index].frame = tlbEntryLo & PAGE_MASK;
  tlb[index].write = tlbEntryLo & TLB_WRITE ? true : false;
  tlb[index].valid = tlbEntryLo & TLB_VALID ? true : false;
  if (debugWrite) {
    cPrintf("**** TLB[%02d] <- 0x%08X 0x%08X %c %c ****\n",
            index, tlb[index].page, tlb[index].frame,
            tlb[index].write ? 'w' : '-',
            tlb[index].valid ? 'v' : '-');
  }
}
 
 
void mmuTbri(void) {
  int index;
 
  index = tlbIndex & TLB_MASK;
  tlbEntryHi = tlb[index].page;
  tlbEntryLo = tlb[index].frame;
  if (tlb[index].write) {
    tlbEntryLo |= TLB_WRITE;
  }
  if (tlb[index].valid) {
    tlbEntryLo |= TLB_VALID;
  }
}
 
 
void mmuTbwi(void) {
  int index;
 
  index = tlbIndex & TLB_MASK;
  tlb[index].page = tlbEntryHi & PAGE_MASK;
  tlb[index].frame = tlbEntryLo & PAGE_MASK;
  tlb[index].write = tlbEntryLo & TLB_WRITE ? true : false;
  tlb[index].valid = tlbEntryLo & TLB_VALID ? true : false;
  if (debugWrite) {
    cPrintf("**** TLB[%02d] <- 0x%08X 0x%08X %c %c ****\n",
            index, tlb[index].page, tlb[index].frame,
            tlb[index].write ? 'w' : '-',
            tlb[index].valid ? 'v' : '-');
  }
}
 
 
TLB_Entry mmuGetTLB(int index) {
  return tlb[index & TLB_MASK];
}
 
 
void mmuSetTLB(int index, TLB_Entry tlbEntry) {
  index &= TLB_MASK;
  tlb[index] = tlbEntry;
  if (debugWrite) {
    cPrintf("**** TLB[%02d] <- 0x%08X 0x%08X %c %c ****\n",
            index, tlb[index].page, tlb[index].frame,
            tlb[index].write ? 'w' : '-',
            tlb[index].valid ? 'v' : '-');
  }
}
 
 
void mmuReset(void) {
  int i;
 
  cPrintf("Resetting MMU...\n");
  for (i = 0; i < TLB_SIZE; i++) {
    tlb[i].page = rand() & PAGE_MASK;
    tlb[i].frame = rand() & PAGE_MASK;
    tlb[i].write = rand() & 0x1000 ? true : false;
    tlb[i].valid = rand() & 0x1000 ? true : false;
    if (debugWrite) {
      cPrintf("**** TLB[%02d] <- 0x%08X 0x%08X %c %c ****\n",
              i, tlb[i].page, tlb[i].frame,
              tlb[i].write ? 'w' : '-',
              tlb[i].valid ? 'v' : '-');
    }
  }
  tlbIndex = rand() & TLB_MASK;
  tlbEntryHi = rand() & PAGE_MASK;
  tlbEntryLo = rand() & (PAGE_MASK | TLB_WRITE | TLB_VALID);
  mmuBadAddr = rand();
  mmuBadAccs = rand() & MMU_ACCS_MASK;
  randomIndex = TLB_MASK;
}
 
 
void mmuInit(void) {
  mmuReset();
}
 
 
void mmuExit(void) {
}

Line No.	Rev	Author	Line
1	8	hellwig	`/*`
2			`* mmu.c -- MMU simulation`
3			`*/`
4
5
6			`#include <stdio.h>`
7			`#include <stdlib.h>`
8			`#include <string.h>`
9			`#include <setjmp.h>`
10
11			`#include "common.h"`
12			`#include "console.h"`
13			`#include "error.h"`
14			`#include "except.h"`
15			`#include "cpu.h"`
16			`#include "mmu.h"`
17			`#include "memory.h"`
18
19
20			`static Bool debugUse = false;`
21			`static Bool debugWrite = false;`
22
23
24			`static TLB_Entry tlb[TLB_SIZE];`
25			`static Word tlbIndex;`
26			`static Word tlbEntryHi;`
27			`static Word tlbEntryLo;`
28	78	hellwig	`static Word mmuBadAddr;`
29	168	hellwig	`static Word mmuBadAccs;`
30	8	hellwig
31	202	hellwig	`static int randomIndex;`
32	8	hellwig
33	202	hellwig
34			`static void updateRandomIndex(void) {`
35			`if (randomIndex == TLB_FIXED) {`
36			`randomIndex = TLB_MASK;`
37			`} else {`
38			`randomIndex--;`
39			`}`
40			`}`
41
42
43	8	hellwig	`static int assoc(Word page) {`
44			`int n, i;`
45
46			`n = -1;`
47			`for (i = 0; i < TLB_SIZE; i++) {`
48			`if (tlb[i].page == page) {`
49			`n = i;`
50			`}`
51			`}`
52			`return n;`
53			`}`
54
55
56	168	hellwig	`static Word v2p(Word vAddr, Bool userMode, Bool writing, int accsWidth) {`
57	8	hellwig	`Word pAddr;`
58			`Word page, offset;`
59			`int index;`
60
61			`if (debugUse) {`
62			`cPrintf("**** vAddr = 0x%08X", vAddr);`
63			`}`
64			`if ((vAddr & 0x80000000) != 0 && userMode) {`
65			`/* trying to access a privileged address from user mode */`
66	168	hellwig	`mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) \| accsWidth;`
67	78	hellwig	`mmuBadAddr = vAddr;`
68	8	hellwig	`throwException(EXC_PRV_ADDRESS);`
69			`}`
70	203	hellwig	`updateRandomIndex();`
71	8	hellwig	`if ((vAddr & 0xC0000000) == 0xC0000000) {`
72			`/* unmapped address space */`
73	166	hellwig	`/* simulate delay introduced by assoc when using mapped`
74			`addresses but not experienced with unmapped addresses */`
75			`assoc(0);`
76	8	hellwig	`pAddr = vAddr & ~0xC0000000;`
77			`} else {`
78			`/* mapped address space */`
79			`page = vAddr & PAGE_MASK;`
80			`offset = vAddr & OFFSET_MASK;`
81			`index = assoc(page);`
82			`if (index == -1) {`
83			`/* TLB miss exception */`
84	168	hellwig	`mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) \| accsWidth;`
85	78	hellwig	`mmuBadAddr = vAddr;`
86	8	hellwig	`tlbEntryHi = page;`
87			`throwException(EXC_TLB_MISS);`
88			`}`
89			`if (!tlb[index].valid) {`
90			`/* TLB invalid exception */`
91	168	hellwig	`mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) \| accsWidth;`
92	78	hellwig	`mmuBadAddr = vAddr;`
93	8	hellwig	`tlbEntryHi = page;`
94			`throwException(EXC_TLB_INVALID);`
95			`}`
96			`if (!tlb[index].write && writing) {`
97			`/* TLB write exception */`
98	168	hellwig	`mmuBadAccs = (writing ? MMU_ACCS_WRITE : MMU_ACCS_READ) \| accsWidth;`
99	78	hellwig	`mmuBadAddr = vAddr;`
100	8	hellwig	`tlbEntryHi = page;`
101			`throwException(EXC_TLB_WRITE);`
102			`}`
103			`pAddr = tlb[index].frame \| offset;`
104			`}`
105			`if (debugUse) {`
106			`cPrintf(", pAddr = 0x%08X ****\n", pAddr);`
107			`}`
108			`return pAddr;`
109			`}`
110
111
112			`Word mmuReadWord(Word vAddr, Bool userMode) {`
113			`if ((vAddr & 3) != 0) {`
114			`/* throw illegal address exception */`
115	168	hellwig	`mmuBadAccs = MMU_ACCS_READ \| MMU_ACCS_WORD;`
116	78	hellwig	`mmuBadAddr = vAddr;`
117	8	hellwig	`throwException(EXC_ILL_ADDRESS);`
118			`}`
119	168	hellwig	`return memoryReadWord(v2p(vAddr, userMode, false, MMU_ACCS_WORD));`
120	8	hellwig	`}`
121
122
123			`Half mmuReadHalf(Word vAddr, Bool userMode) {`
124			`if ((vAddr & 1) != 0) {`
125			`/* throw illegal address exception */`
126	168	hellwig	`mmuBadAccs = MMU_ACCS_READ \| MMU_ACCS_HALF;`
127	78	hellwig	`mmuBadAddr = vAddr;`
128	8	hellwig	`throwException(EXC_ILL_ADDRESS);`
129			`}`
130	168	hellwig	`return memoryReadHalf(v2p(vAddr, userMode, false, MMU_ACCS_HALF));`
131	8	hellwig	`}`
132
133
134			`Byte mmuReadByte(Word vAddr, Bool userMode) {`
135	168	hellwig	`return memoryReadByte(v2p(vAddr, userMode, false, MMU_ACCS_BYTE));`
136	8	hellwig	`}`
137
138
139			`void mmuWriteWord(Word vAddr, Word data, Bool userMode) {`
140			`if ((vAddr & 3) != 0) {`
141			`/* throw illegal address exception */`
142	168	hellwig	`mmuBadAccs = MMU_ACCS_WRITE \| MMU_ACCS_WORD;`
143	78	hellwig	`mmuBadAddr = vAddr;`
144	8	hellwig	`throwException(EXC_ILL_ADDRESS);`
145			`}`
146	168	hellwig	`memoryWriteWord(v2p(vAddr, userMode, true, MMU_ACCS_WORD), data);`
147	8	hellwig	`}`
148
149
150			`void mmuWriteHalf(Word vAddr, Half data, Bool userMode) {`
151			`if ((vAddr & 1) != 0) {`
152			`/* throw illegal address exception */`
153	168	hellwig	`mmuBadAccs = MMU_ACCS_WRITE \| MMU_ACCS_HALF;`
154	78	hellwig	`mmuBadAddr = vAddr;`
155	8	hellwig	`throwException(EXC_ILL_ADDRESS);`
156			`}`
157	168	hellwig	`memoryWriteHalf(v2p(vAddr, userMode, true, MMU_ACCS_HALF), data);`
158	8	hellwig	`}`
159
160
161			`void mmuWriteByte(Word vAddr, Byte data, Bool userMode) {`
162	168	hellwig	`memoryWriteByte(v2p(vAddr, userMode, true, MMU_ACCS_BYTE), data);`
163	8	hellwig	`}`
164
165
166			`Word mmuGetIndex(void) {`
167			`return tlbIndex;`
168			`}`
169
170
171			`void mmuSetIndex(Word value) {`
172			`tlbIndex = value & TLB_MASK;`
173			`}`
174
175
176			`Word mmuGetEntryHi(void) {`
177			`return tlbEntryHi;`
178			`}`
179
180
181			`void mmuSetEntryHi(Word value) {`
182			`tlbEntryHi = value & PAGE_MASK;`
183			`}`
184
185
186			`Word mmuGetEntryLo(void) {`
187			`return tlbEntryLo;`
188			`}`
189
190
191			`void mmuSetEntryLo(Word value) {`
192			`tlbEntryLo = value & (PAGE_MASK \| TLB_WRITE \| TLB_VALID);`
193			`}`
194
195
196			`Word mmuGetBadAddr(void) {`
197	78	hellwig	`return mmuBadAddr;`
198	8	hellwig	`}`
199
200
201			`void mmuSetBadAddr(Word value) {`
202	78	hellwig	`mmuBadAddr = value;`
203	8	hellwig	`}`
204
205
206	168	hellwig	`Word mmuGetBadAccs(void) {`
207			`return mmuBadAccs;`
208			`}`
209
210
211			`void mmuSetBadAccs(Word value) {`
212			`mmuBadAccs = value;`
213			`}`
214
215
216	8	hellwig	`void mmuTbs(void) {`
217			`int index;`
218
219			`index = assoc(tlbEntryHi & PAGE_MASK);`
220			`if (index == -1) {`
221			`tlbIndex = 0x80000000;`
222			`} else {`
223			`tlbIndex = index;`
224			`}`
225			`}`
226
227
228			`void mmuTbwr(void) {`
229			`int index;`
230
231			`/* choose a random index, but don't touch fixed entries */`
232	202	hellwig	`index = randomIndex;`
233	8	hellwig	`tlb[index].page = tlbEntryHi & PAGE_MASK;`
234			`tlb[index].frame = tlbEntryLo & PAGE_MASK;`
235			`tlb[index].write = tlbEntryLo & TLB_WRITE ? true : false;`
236			`tlb[index].valid = tlbEntryLo & TLB_VALID ? true : false;`
237			`if (debugWrite) {`
238			`cPrintf("** TLB[%02d] <- 0x%08X 0x%08X %c %c **\n",`
239			`index, tlb[index].page, tlb[index].frame,`
240			`tlb[index].write ? 'w' : '-',`
241			`tlb[index].valid ? 'v' : '-');`
242			`}`
243			`}`
244
245
246			`void mmuTbri(void) {`
247			`int index;`
248
249			`index = tlbIndex & TLB_MASK;`
250			`tlbEntryHi = tlb[index].page;`
251			`tlbEntryLo = tlb[index].frame;`
252			`if (tlb[index].write) {`
253			`tlbEntryLo \|= TLB_WRITE;`
254			`}`
255			`if (tlb[index].valid) {`
256			`tlbEntryLo \|= TLB_VALID;`
257			`}`
258			`}`
259
260
261			`void mmuTbwi(void) {`
262			`int index;`
263
264			`index = tlbIndex & TLB_MASK;`
265			`tlb[index].page = tlbEntryHi & PAGE_MASK;`
266			`tlb[index].frame = tlbEntryLo & PAGE_MASK;`
267			`tlb[index].write = tlbEntryLo & TLB_WRITE ? true : false;`
268			`tlb[index].valid = tlbEntryLo & TLB_VALID ? true : false;`
269			`if (debugWrite) {`
270			`cPrintf("** TLB[%02d] <- 0x%08X 0x%08X %c %c **\n",`
271			`index, tlb[index].page, tlb[index].frame,`
272			`tlb[index].write ? 'w' : '-',`
273			`tlb[index].valid ? 'v' : '-');`
274			`}`
275			`}`
276
277
278			`TLB_Entry mmuGetTLB(int index) {`
279			`return tlb[index & TLB_MASK];`
280			`}`
281
282
283			`void mmuSetTLB(int index, TLB_Entry tlbEntry) {`
284			`index &= TLB_MASK;`
285			`tlb[index] = tlbEntry;`
286			`if (debugWrite) {`
287			`cPrintf("** TLB[%02d] <- 0x%08X 0x%08X %c %c **\n",`
288			`index, tlb[index].page, tlb[index].frame,`
289			`tlb[index].write ? 'w' : '-',`
290			`tlb[index].valid ? 'v' : '-');`
291			`}`
292			`}`
293
294
295			`void mmuReset(void) {`
296			`int i;`
297
298			`cPrintf("Resetting MMU...\n");`
299			`for (i = 0; i < TLB_SIZE; i++) {`
300			`tlb[i].page = rand() & PAGE_MASK;`
301			`tlb[i].frame = rand() & PAGE_MASK;`
302			`tlb[i].write = rand() & 0x1000 ? true : false;`
303			`tlb[i].valid = rand() & 0x1000 ? true : false;`
304			`if (debugWrite) {`
305			`cPrintf("** TLB[%02d] <- 0x%08X 0x%08X %c %c **\n",`
306			`i, tlb[i].page, tlb[i].frame,`
307			`tlb[i].write ? 'w' : '-',`
308			`tlb[i].valid ? 'v' : '-');`
309			`}`
310			`}`
311			`tlbIndex = rand() & TLB_MASK;`
312			`tlbEntryHi = rand() & PAGE_MASK;`
313			`tlbEntryLo = rand() & (PAGE_MASK \| TLB_WRITE \| TLB_VALID);`
314	78	hellwig	`mmuBadAddr = rand();`
315	168	hellwig	`mmuBadAccs = rand() & MMU_ACCS_MASK;`
316	202	hellwig	`randomIndex = TLB_MASK;`
317	8	hellwig	`}`
318
319
320			`void mmuInit(void) {`
321			`mmuReset();`
322			`}`
323
324
325			`void mmuExit(void) {`
326			`}`

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[/] [eco32/] [trunk/] [sim/] [mmu.c] - Blame information for rev 203