tlb.cc revision 8607:5fb918115c07 
1/*
2 * Copyright (c) 2001-2005 The Regents of The University of Michigan
3 * Copyright (c) 2007 MIPS Technologies, Inc.
4 * Copyright (c) 2007-2008 The Florida State University
5 * Copyright (c) 2009 The University of Edinburgh
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are
10 * met: redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer;
12 * redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution;
15 * neither the name of the copyright holders nor the names of its
16 * contributors may be used to endorse or promote products derived from
17 * this software without specific prior written permission.
18 *
19 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
20 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
21 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
22 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
23 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
24 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
25 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
26 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
27 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
28 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
29 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
30 *
31 * Authors: Nathan Binkert
32 *          Steve Reinhardt
33 *          Jaidev Patwardhan
34 *          Stephen Hines
35 *          Timothy M. Jones
36 */
37
38#include <string>
39#include <vector>
40
41#include "arch/power/faults.hh"
42#include "arch/power/pagetable.hh"
43#include "arch/power/tlb.hh"
44#include "arch/power/utility.hh"
45#include "base/inifile.hh"
46#include "base/str.hh"
47#include "base/trace.hh"
48#include "cpu/thread_context.hh"
49#include "debug/Power.hh"
50#include "debug/TLB.hh"
51#include "mem/page_table.hh"
52#include "params/PowerTLB.hh"
53#include "sim/process.hh"
54
55using namespace std;
56using namespace PowerISA;
57
58///////////////////////////////////////////////////////////////////////
59//
60//  POWER TLB
61//
62
63#define MODE2MASK(X) (1 << (X))
64
65TLB::TLB(const Params *p)
66    : BaseTLB(p), size(p->size), nlu(0)
67{
68    table = new PowerISA::PTE[size];
69    memset(table, 0, sizeof(PowerISA::PTE[size]));
70    smallPages = 0;
71}
72
73TLB::~TLB()
74{
75    if (table)
76        delete [] table;
77}
78
79// look up an entry in the TLB
80PowerISA::PTE *
81TLB::lookup(Addr vpn, uint8_t asn) const
82{
83    // assume not found...
84    PowerISA::PTE *retval = NULL;
85    PageTable::const_iterator i = lookupTable.find(vpn);
86    if (i != lookupTable.end()) {
87        while (i->first == vpn) {
88            int index = i->second;
89            PowerISA::PTE *pte = &table[index];
90            Addr Mask = pte->Mask;
91            Addr InvMask = ~Mask;
92            Addr VPN  = pte->VPN;
93            if (((vpn & InvMask) == (VPN & InvMask))
94               && (pte->G  || (asn == pte->asid))) {
95
96                // We have a VPN + ASID Match
97                retval = pte;
98                break;
99            }
100            ++i;
101        }
102    }
103
104    DPRINTF(TLB, "lookup %#x, asn %#x -> %s ppn %#x\n", vpn, (int)asn,
105            retval ? "hit" : "miss", retval ? retval->PFN1 : 0);
106    return retval;
107}
108
109PowerISA::PTE*
110TLB::getEntry(unsigned Index) const
111{
112    // Make sure that Index is valid
113    assert(Index<size);
114    return &table[Index];
115}
116
117int
118TLB::probeEntry(Addr vpn,uint8_t asn) const
119{
120    // assume not found...
121    int Ind = -1;
122    PageTable::const_iterator i = lookupTable.find(vpn);
123    if (i != lookupTable.end()) {
124        while (i->first == vpn) {
125            int index = i->second;
126            PowerISA::PTE *pte = &table[index];
127            Addr Mask = pte->Mask;
128            Addr InvMask = ~Mask;
129            Addr VPN  = pte->VPN;
130            if (((vpn & InvMask) == (VPN & InvMask))
131                && (pte->G  || (asn == pte->asid))) {
132
133                // We have a VPN + ASID Match
134                Ind = index;
135                break;
136            }
137            ++i;
138        }
139    }
140
141    DPRINTF(Power, "VPN: %x, asid: %d, Result of TLBP: %d\n", vpn, asn, Ind);
142    return Ind;
143}
144
145inline Fault
146TLB::checkCacheability(RequestPtr &req)
147{
148    Addr VAddrUncacheable = 0xA0000000;
149    if ((req->getVaddr() & VAddrUncacheable) == VAddrUncacheable) {
150
151        // mark request as uncacheable
152        req->setFlags(Request::UNCACHEABLE);
153    }
154    return NoFault;
155}
156
157void
158TLB::insertAt(PowerISA::PTE &pte, unsigned Index, int _smallPages)
159{
160    smallPages=_smallPages;
161    if (Index > size){
162        warn("Attempted to write at index (%d) beyond TLB size (%d)",
163             Index, size);
164    } else {
165
166        // Update TLB
167        if (table[Index].V0 == true || table[Index].V1 == true) {
168
169            // Previous entry is valid
170            PageTable::iterator i = lookupTable.find(table[Index].VPN);
171            lookupTable.erase(i);
172        }
173        table[Index]=pte;
174
175        // Update fast lookup table
176        lookupTable.insert(make_pair(table[Index].VPN, Index));
177    }
178}
179
180// insert a new TLB entry
181void
182TLB::insert(Addr addr, PowerISA::PTE &pte)
183{
184    fatal("TLB Insert not yet implemented\n");
185}
186
187void
188TLB::flushAll()
189{
190    DPRINTF(TLB, "flushAll\n");
191    memset(table, 0, sizeof(PowerISA::PTE[size]));
192    lookupTable.clear();
193    nlu = 0;
194}
195
196void
197TLB::serialize(ostream &os)
198{
199    SERIALIZE_SCALAR(size);
200    SERIALIZE_SCALAR(nlu);
201
202    for (int i = 0; i < size; i++) {
203        nameOut(os, csprintf("%s.PTE%d", name(), i));
204        table[i].serialize(os);
205    }
206}
207
208void
209TLB::unserialize(Checkpoint *cp, const string &section)
210{
211    UNSERIALIZE_SCALAR(size);
212    UNSERIALIZE_SCALAR(nlu);
213
214    for (int i = 0; i < size; i++) {
215        table[i].unserialize(cp, csprintf("%s.PTE%d", section, i));
216        if (table[i].V0 || table[i].V1) {
217            lookupTable.insert(make_pair(table[i].VPN, i));
218        }
219    }
220}
221
222void
223TLB::regStats()
224{
225    read_hits
226        .name(name() + ".read_hits")
227        .desc("DTB read hits")
228        ;
229
230    read_misses
231        .name(name() + ".read_misses")
232        .desc("DTB read misses")
233        ;
234
235
236    read_accesses
237        .name(name() + ".read_accesses")
238        .desc("DTB read accesses")
239        ;
240
241    write_hits
242        .name(name() + ".write_hits")
243        .desc("DTB write hits")
244        ;
245
246    write_misses
247        .name(name() + ".write_misses")
248        .desc("DTB write misses")
249        ;
250
251
252    write_accesses
253        .name(name() + ".write_accesses")
254        .desc("DTB write accesses")
255        ;
256
257    hits
258        .name(name() + ".hits")
259        .desc("DTB hits")
260        ;
261
262    misses
263        .name(name() + ".misses")
264        .desc("DTB misses")
265        ;
266
267    accesses
268        .name(name() + ".accesses")
269        .desc("DTB accesses")
270        ;
271
272    hits = read_hits + write_hits;
273    misses = read_misses + write_misses;
274    accesses = read_accesses + write_accesses;
275}
276
277Fault
278TLB::translateInst(RequestPtr req, ThreadContext *tc)
279{
280    // Instruction accesses must be word-aligned
281    if (req->getVaddr() & 0x3) {
282        DPRINTF(TLB, "Alignment Fault on %#x, size = %d\n", req->getVaddr(),
283                req->getSize());
284        return new AlignmentFault();
285    }
286
287     Process * p = tc->getProcessPtr();
288
289     Fault fault = p->pTable->translate(req);
290    if (fault != NoFault)
291        return fault;
292
293    return NoFault;
294}
295
296Fault
297TLB::translateData(RequestPtr req, ThreadContext *tc, bool write)
298{
299    Process * p = tc->getProcessPtr();
300
301    Fault fault = p->pTable->translate(req);
302    if (fault != NoFault)
303        return fault;
304
305    return NoFault;
306}
307
308Fault
309TLB::translateAtomic(RequestPtr req, ThreadContext *tc, Mode mode)
310{
311#if !FULL_SYSTEM
312    if (mode == Execute)
313        return translateInst(req, tc);
314    else
315        return translateData(req, tc, mode == Write);
316#else
317  fatal("translate atomic not yet implemented\n");
318#endif
319}
320
321void
322TLB::translateTiming(RequestPtr req, ThreadContext *tc,
323                     Translation *translation, Mode mode)
324{
325    assert(translation);
326    translation->finish(translateAtomic(req, tc, mode), req, tc, mode);
327}
328
329PowerISA::PTE &
330TLB::index(bool advance)
331{
332    PowerISA::PTE *pte = &table[nlu];
333
334    if (advance)
335        nextnlu();
336
337    return *pte;
338}
339
340PowerISA::TLB *
341PowerTLBParams::create()
342{
343    return new PowerISA::TLB(this);
344}
345