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add function _prtable_lookup and unit test
[soc.git] / src / soc / decoder / isa / radixmmu.py
1 # SPDX-License-Identifier: LGPLv3+
2 # Copyright (C) 2020, 2021 Luke Kenneth Casson Leighton <lkcl@lkcl.net>
3 # Copyright (C) 2021 Tobias Platen
4 # Funded by NLnet http://nlnet.nl
5 """core of the python-based POWER9 simulator
6
7 this is part of a cycle-accurate POWER9 simulator. its primary purpose is
8 not speed, it is for both learning and educational purposes, as well as
9 a method of verifying the HDL.
10
11 related bugs:
12
13 * https://bugs.libre-soc.org/show_bug.cgi?id=604
14 """
15
16 from nmigen.back.pysim import Settle
17 from copy import copy
18 from soc.decoder.selectable_int import (FieldSelectableInt, SelectableInt,
19 selectconcat)
20 from soc.decoder.helpers import exts, gtu, ltu, undefined
21 from soc.decoder.isa.mem import Mem
22 from soc.consts import MSRb # big-endian (PowerISA versions)
23
24 import math
25 import sys
26 import unittest
27
28 # very quick, TODO move to SelectableInt utils later
29 def genmask(shift, size):
30 res = SelectableInt(0, size)
31 for i in range(size):
32 if i < shift:
33 res[size-1-i] = SelectableInt(1, 1)
34 return res
35
36 # NOTE: POWER 3.0B annotation order! see p4 1.3.2
37 # MSB is indexed **LOWEST** (sigh)
38 # from gem5 radixwalk.hh
39 # Bitfield<63> valid; 64 - (63 + 1) = 0
40 # Bitfield<62> leaf; 64 - (62 + 1) = 1
41
42 def rpte_valid(r):
43 return bool(r[0])
44
45 def rpte_leaf(r):
46 return bool(r[1])
47
48 ## Shift address bits 61--12 right by 0--47 bits and
49 ## supply the least significant 16 bits of the result.
50 def addrshift(addr,shift):
51 x = addr.value >> shift.value
52 return SelectableInt(x,16)
53
54 def NLB(x):
55 """
56 Next Level Base
57 right shifted by 8
58 """
59 return x[4:55]
60
61 def NLS(x):
62 """
63 Next Level Size
64 NLS >= 5
65 """
66 return x[59:63]
67
68 """
69 Get Root Page
70
71 //Accessing 2nd double word of partition table (pate1)
72 //Ref: Power ISA Manual v3.0B, Book-III, section 5.7.6.1
73 // PTCR Layout
74 // ====================================================
75 // -----------------------------------------------
76 // | /// | PATB | /// | PATS |
77 // -----------------------------------------------
78 // 0 4 51 52 58 59 63
79 // PATB[4:51] holds the base address of the Partition Table,
80 // right shifted by 12 bits.
81 // This is because the address of the Partition base is
82 // 4k aligned. Hence, the lower 12bits, which are always
83 // 0 are ommitted from the PTCR.
84 //
85 // Thus, The Partition Table Base is obtained by (PATB << 12)
86 //
87 // PATS represents the partition table size right-shifted by 12 bits.
88 // The minimal size of the partition table is 4k.
89 // Thus partition table size = (1 << PATS + 12).
90 //
91 // Partition Table
92 // ====================================================
93 // 0 PATE0 63 PATE1 127
94 // |----------------------|----------------------|
95 // | | |
96 // |----------------------|----------------------|
97 // | | |
98 // |----------------------|----------------------|
99 // | | | <-- effLPID
100 // |----------------------|----------------------|
101 // .
102 // .
103 // .
104 // |----------------------|----------------------|
105 // | | |
106 // |----------------------|----------------------|
107 //
108 // The effective LPID forms the index into the Partition Table.
109 //
110 // Each entry in the partition table contains 2 double words, PATE0, PATE1,
111 // corresponding to that partition.
112 //
113 // In case of Radix, The structure of PATE0 and PATE1 is as follows.
114 //
115 // PATE0 Layout
116 // -----------------------------------------------
117 // |1|RTS1|/| RPDB | RTS2 | RPDS |
118 // -----------------------------------------------
119 // 0 1 2 3 4 55 56 58 59 63
120 //
121 // HR[0] : For Radix Page table, first bit should be 1.
122 // RTS1[1:2] : Gives one fragment of the Radix treesize
123 // RTS2[56:58] : Gives the second fragment of the Radix Tree size.
124 // RTS = (RTS1 << 3 + RTS2) + 31.
125 //
126 // RPDB[4:55] = Root Page Directory Base.
127 // RPDS = Logarithm of Root Page Directory Size right shifted by 3.
128 // Thus, Root page directory size = 1 << (RPDS + 3).
129 // Note: RPDS >= 5.
130 //
131 // PATE1 Layout
132 // -----------------------------------------------
133 // |///| PRTB | // | PRTS |
134 // -----------------------------------------------
135 // 0 3 4 51 52 58 59 63
136 //
137 // PRTB[4:51] = Process Table Base. This is aligned to size.
138 // PRTS[59: 63] = Process Table Size right shifted by 12.
139 // Minimal size of the process table is 4k.
140 // Process Table Size = (1 << PRTS + 12).
141 // Note: PRTS <= 24.
142 //
143 // Computing the size aligned Process Table Base:
144 // table_base = (PRTB & ~((1 << PRTS) - 1)) << 12
145 // Thus, the lower 12+PRTS bits of table_base will
146 // be zero.
147
148
149 //Ref: Power ISA Manual v3.0B, Book-III, section 5.7.6.2
150 //
151 // Process Table
152 // ==========================
153 // 0 PRTE0 63 PRTE1 127
154 // |----------------------|----------------------|
155 // | | |
156 // |----------------------|----------------------|
157 // | | |
158 // |----------------------|----------------------|
159 // | | | <-- effPID
160 // |----------------------|----------------------|
161 // .
162 // .
163 // .
164 // |----------------------|----------------------|
165 // | | |
166 // |----------------------|----------------------|
167 //
168 // The effective Process id (PID) forms the index into the Process Table.
169 //
170 // Each entry in the partition table contains 2 double words, PRTE0, PRTE1,
171 // corresponding to that process
172 //
173 // In case of Radix, The structure of PRTE0 and PRTE1 is as follows.
174 //
175 // PRTE0 Layout
176 // -----------------------------------------------
177 // |/|RTS1|/| RPDB | RTS2 | RPDS |
178 // -----------------------------------------------
179 // 0 1 2 3 4 55 56 58 59 63
180 //
181 // RTS1[1:2] : Gives one fragment of the Radix treesize
182 // RTS2[56:58] : Gives the second fragment of the Radix Tree size.
183 // RTS = (RTS1 << 3 + RTS2) << 31,
184 // since minimal Radix Tree size is 4G.
185 //
186 // RPDB = Root Page Directory Base.
187 // RPDS = Root Page Directory Size right shifted by 3.
188 // Thus, Root page directory size = RPDS << 3.
189 // Note: RPDS >= 5.
190 //
191 // PRTE1 Layout
192 // -----------------------------------------------
193 // | /// |
194 // -----------------------------------------------
195 // 0 63
196 // All bits are reserved.
197
198
199 """
200
201 testmem = {
202
203 0x10000: # PARTITION_TABLE_2 (not implemented yet)
204 # PATB_GR=1 PRTB=0x1000 PRTS=0xb
205 0x800000000100000b,
206
207 0x30000: # RADIX_ROOT_PTE
208 # V = 1 L = 0 NLB = 0x400 NLS = 9
209 0x8000000000040009,
210 0x40000: # RADIX_SECOND_LEVEL
211 # V = 1 L = 1 SW = 0 RPN = 0
212 # R = 1 C = 1 ATT = 0 EAA 0x7
213 0xc000000000000187,
214
215 0x1000000: # PROCESS_TABLE_3
216 # RTS1 = 0x2 RPDB = 0x300 RTS2 = 0x5 RPDS = 13
217 0x40000000000300ad,
218 }
219
220 # this one has a 2nd level RADIX with a RPN of 0x5000
221 testmem2 = {
222
223 0x10000: # PARTITION_TABLE_2 (not implemented yet)
224 # PATB_GR=1 PRTB=0x1000 PRTS=0xb
225 0x800000000100000b,
226
227 0x30000: # RADIX_ROOT_PTE
228 # V = 1 L = 0 NLB = 0x400 NLS = 9
229 0x8000000000040009,
230 0x40000: # RADIX_SECOND_LEVEL
231 # V = 1 L = 1 SW = 0 RPN = 0x5000
232 # R = 1 C = 1 ATT = 0 EAA 0x7
233 0xc000000005000187,
234
235 0x1000000: # PROCESS_TABLE_3
236 # RTS1 = 0x2 RPDB = 0x300 RTS2 = 0x5 RPDS = 13
237 0x40000000000300ad,
238 }
239
240
241 testresult = """
242 prtbl = 1000000
243 DCACHE GET 1000000 PROCESS_TABLE_3
244 DCACHE GET 30000 RADIX_ROOT_PTE V = 1 L = 0
245 DCACHE GET 40000 RADIX_SECOND_LEVEL V = 1 L = 1
246 DCACHE GET 10000 PARTITION_TABLE_2
247 translated done 1 err 0 badtree 0 addr 40000 pte 0
248 """
249
250 # see qemu/target/ppc/mmu-radix64.c for reference
251 class RADIX:
252 def __init__(self, mem, caller):
253 self.mem = mem
254 self.caller = caller
255 if caller is not None:
256 self.dsisr = self.caller.spr["DSISR"]
257 self.dar = self.caller.spr["DAR"]
258 self.pidr = self.caller.spr["PIDR"]
259 self.prtbl = self.caller.spr["PRTBL"]
260 self.msr = self.caller.msr
261
262 # cached page table stuff
263 self.pgtbl0 = 0
264 self.pt0_valid = False
265 self.pgtbl3 = 0
266 self.pt3_valid = False
267
268 def __call__(self, addr, sz):
269 val = self.ld(addr.value, sz, swap=False)
270 print("RADIX memread", addr, sz, val)
271 return SelectableInt(val, sz*8)
272
273 def ld(self, address, width=8, swap=True, check_in_mem=False,
274 instr_fetch=False):
275 print("RADIX: ld from addr 0x%x width %d" % (address, width))
276
277 priv = ~(self.msr(MSR_PR).value) # problem-state ==> privileged
278 if instr_fetch:
279 mode = 'EXECUTE'
280 else:
281 mode = 'LOAD'
282 addr = SelectableInt(address, 64)
283 (shift, mbits, pgbase) = self._decode_prte(addr)
284 #shift = SelectableInt(0, 32)
285
286 pte = self._walk_tree(addr, pgbase, mode, mbits, shift, priv)
287
288 # use pte to caclculate phys address
289 return self.mem.ld(address, width, swap, check_in_mem)
290
291 # XXX set SPRs on error
292
293 # TODO implement
294 def st(self, address, v, width=8, swap=True):
295 print("RADIX: st to addr 0x%x width %d data %x" % (address, width, v))
296
297 priv = ~(self.msr(MSR_PR).value) # problem-state ==> privileged
298 mode = 'STORE'
299 addr = SelectableInt(address, 64)
300 (shift, mbits, pgbase) = self._decode_prte(addr)
301 pte = self._walk_tree(addr, pgbase, mode, mbits, shift, priv)
302
303 # use pte to caclculate phys address (addr)
304 return self.mem.st(addr.value, v, width, swap)
305
306 # XXX set SPRs on error
307
308 def memassign(self, addr, sz, val):
309 print("memassign", addr, sz, val)
310 self.st(addr.value, val.value, sz, swap=False)
311
312 def _next_level(self, addr, entry_width, swap, check_in_mem):
313 # implement read access to mmu mem here
314
315 value = self.mem.ld(addr.value, 8, False, check_in_mem)
316 assert(value is not None, "address lookup %x not found" % addr.value)
317
318 print("addr", hex(addr.value))
319 data = SelectableInt(value, 64) # convert to SelectableInt
320 print("value", hex(value))
321 # index += 1
322 return data;
323
324 def _prtable_lookup(self, prtbl, addr, pid):
325 # v.shift := unsigned('0' & r.prtbl(4 downto 0));
326 shift = prtbl[59:63]
327 print("shift",shift)
328 prtable_addr = self._get_prtable_addr(shift, prtbl, addr, pid)
329 print("prtable_addr",prtable_addr)
330 # TODO check and loop if needed
331
332 assert(prtable_addr==0x1000000)
333 print("fetch data from PROCESS_TABLE_3")
334 return "TODO"
335
336 def _walk_tree(self, addr, pgbase, mode, mbits, shift, priv=1):
337 """walk tree
338
339 // vaddr 64 Bit
340 // vaddr |-----------------------------------------------------|
341 // | Unused | Used |
342 // |-----------|-----------------------------------------|
343 // | 0000000 | usefulBits = X bits (typically 52) |
344 // |-----------|-----------------------------------------|
345 // | |<--Cursize---->| |
346 // | | Index | |
347 // | | into Page | |
348 // | | Directory | |
349 // |-----------------------------------------------------|
350 // | |
351 // V |
352 // PDE |---------------------------| |
353 // |V|L|//| NLB |///|NLS| |
354 // |---------------------------| |
355 // PDE = Page Directory Entry |
356 // [0] = V = Valid Bit |
357 // [1] = L = Leaf bit. If 0, then |
358 // [4:55] = NLB = Next Level Base |
359 // right shifted by 8 |
360 // [59:63] = NLS = Next Level Size |
361 // | NLS >= 5 |
362 // | V
363 // | |--------------------------|
364 // | | usfulBits = X-Cursize |
365 // | |--------------------------|
366 // |---------------------><--NLS-->| |
367 // | Index | |
368 // | into | |
369 // | PDE | |
370 // |--------------------------|
371 // |
372 // If the next PDE obtained by |
373 // (NLB << 8 + 8 * index) is a |
374 // nonleaf, then repeat the above. |
375 // |
376 // If the next PDE is a leaf, |
377 // then Leaf PDE structure is as |
378 // follows |
379 // |
380 // |
381 // Leaf PDE |
382 // |------------------------------| |----------------|
383 // |V|L|sw|//|RPN|sw|R|C|/|ATT|EAA| | usefulBits |
384 // |------------------------------| |----------------|
385 // [0] = V = Valid Bit |
386 // [1] = L = Leaf Bit = 1 if leaf |
387 // PDE |
388 // [2] = Sw = Sw bit 0. |
389 // [7:51] = RPN = Real Page Number, V
390 // real_page = RPN << 12 -------------> Logical OR
391 // [52:54] = Sw Bits 1:3 |
392 // [55] = R = Reference |
393 // [56] = C = Change V
394 // [58:59] = Att = Physical Address
395 // 0b00 = Normal Memory
396 // 0b01 = SAO
397 // 0b10 = Non Idenmpotent
398 // 0b11 = Tolerant I/O
399 // [60:63] = Encoded Access
400 // Authority
401 //
402 """
403 # get sprs
404 print("_walk_tree")
405 pidr = self.caller.spr["PIDR"]
406 prtbl = self.caller.spr["PRTBL"]
407 print(pidr)
408 print(prtbl)
409 p = addr[55:63]
410 print("last 8 bits ----------")
411 print
412
413 prtbl = SelectableInt(0x1000000,64) #FIXME do not hardcode
414
415 # get address of root entry
416 shift = selectconcat(SelectableInt(0,1),prtbl[58:63]) # TODO verify
417 addr_next = self._get_prtable_addr(shift, prtbl, addr, pidr)
418 print("starting with prtable, addr_next",addr_next)
419
420 assert(addr_next.bits == 64)
421 assert(addr_next.value == 0x1000000) #TODO
422
423 addr_next = SelectableInt(0x30000,64) # radix root for testing
424
425 # walk tree starts on prtbl
426 while True:
427 print("nextlevel----------------------------")
428 # read an entry
429 swap = False
430 check_in_mem = False
431 entry_width = 8
432
433 data = self._next_level(addr_next, entry_width, swap, check_in_mem)
434 valid = rpte_valid(data)
435 leaf = rpte_leaf(data)
436
437 print(" valid, leaf", valid, leaf)
438 if not valid:
439 return "invalid" # TODO: return error
440 if leaf:
441 print ("is leaf, checking perms")
442 ok = self._check_perms(data, priv, mode)
443 if ok == True: # data was ok, found phys address, return it?
444 paddr = self._get_pte(addrsh, addr, data)
445 print (" phys addr", hex(paddr.value))
446 return paddr
447 return ok # return the error code
448 else:
449 newlookup = self._new_lookup(data, mbits, shift)
450 if newlookup == 'badtree':
451 return newlookup
452 shift, mask, pgbase = newlookup
453 print (" next level", shift, mask, pgbase)
454 shift = SelectableInt(shift.value,16) #THIS is wrong !!!
455 print("calling _get_pgtable_addr")
456 print(mask) #SelectableInt(value=0x9, bits=4)
457 print(pgbase) #SelectableInt(value=0x40000, bits=56)
458 print(shift) #SelectableInt(value=0x4, bits=16) #FIXME
459 pgbase = SelectableInt(pgbase.value, 64)
460 addrsh = addrshift(addr,shift)
461 addr_next = self._get_pgtable_addr(mask, pgbase, addrsh)
462 print("addr_next",addr_next)
463 print("addrsh",addrsh)
464
465 def _new_lookup(self, data, mbits, shift):
466 """
467 mbits := unsigned('0' & data(4 downto 0));
468 if mbits < 5 or mbits > 16 or mbits > r.shift then
469 v.state := RADIX_FINISH;
470 v.badtree := '1'; -- throw error
471 else
472 v.shift := v.shift - mbits;
473 v.mask_size := mbits(4 downto 0);
474 v.pgbase := data(55 downto 8) & x"00"; NLB?
475 v.state := RADIX_LOOKUP; --> next level
476 end if;
477 """
478 mbits = data[59:64]
479 print("mbits=", mbits)
480 if mbits < 5 or mbits > 16: #fixme compare with r.shift
481 print("badtree")
482 return "badtree"
483 # reduce shift (has to be done at same bitwidth)
484 shift = shift - selectconcat(SelectableInt(0, 1), mbits)
485 mask_size = mbits[1:5] # get 4 LSBs
486 pgbase = selectconcat(data[8:56], SelectableInt(0, 8)) # shift up 8
487 return shift, mask_size, pgbase
488
489 def _decode_prte(self, data):
490 """PRTE0 Layout
491 -----------------------------------------------
492 |/|RTS1|/| RPDB | RTS2 | RPDS |
493 -----------------------------------------------
494 0 1 2 3 4 55 56 58 59 63
495 """
496 # note that SelectableInt does big-endian! so the indices
497 # below *directly* match the spec, unlike microwatt which
498 # has to turn them around (to LE)
499 zero = SelectableInt(0, 1)
500 rts = selectconcat(zero,
501 data[56:59], # RTS2
502 data[1:3], # RTS1
503 )
504 masksize = data[59:64] # RPDS
505 mbits = selectconcat(zero, masksize)
506 pgbase = selectconcat(data[8:56], # part of RPDB
507 SelectableInt(0, 16),)
508
509 return (rts, mbits, pgbase)
510
511 def _segment_check(self, addr, mbits, shift):
512 """checks segment valid
513 mbits := '0' & r.mask_size;
514 v.shift := r.shift + (31 - 12) - mbits;
515 nonzero := or(r.addr(61 downto 31) and not finalmask(30 downto 0));
516 if r.addr(63) /= r.addr(62) or nonzero = '1' then
517 v.state := RADIX_FINISH;
518 v.segerror := '1';
519 elsif mbits < 5 or mbits > 16 or mbits > (r.shift + (31 - 12)) then
520 v.state := RADIX_FINISH;
521 v.badtree := '1';
522 else
523 v.state := RADIX_LOOKUP;
524 """
525 # note that SelectableInt does big-endian! so the indices
526 # below *directly* match the spec, unlike microwatt which
527 # has to turn them around (to LE)
528 mask = genmask(shift, 44)
529 nonzero = addr[2:33] & mask[13:44] # mask 31 LSBs (BE numbered 13:44)
530 print ("RADIX _segment_check nonzero", bin(nonzero.value))
531 print ("RADIX _segment_check addr[0-1]", addr[0].value, addr[1].value)
532 if addr[0] != addr[1] or nonzero != 0:
533 return "segerror"
534 limit = shift + (31 - 12)
535 if mbits < 5 or mbits > 16 or mbits > limit:
536 return "badtree"
537 new_shift = shift + (31 - 12) - mbits
538 return new_shift
539
540 def _check_perms(self, data, priv, mode):
541 """check page permissions
542 // Leaf PDE |
543 // |------------------------------| |----------------|
544 // |V|L|sw|//|RPN|sw|R|C|/|ATT|EAA| | usefulBits |
545 // |------------------------------| |----------------|
546 // [0] = V = Valid Bit |
547 // [1] = L = Leaf Bit = 1 if leaf |
548 // PDE |
549 // [2] = Sw = Sw bit 0. |
550 // [7:51] = RPN = Real Page Number, V
551 // real_page = RPN << 12 -------------> Logical OR
552 // [52:54] = Sw Bits 1:3 |
553 // [55] = R = Reference |
554 // [56] = C = Change V
555 // [58:59] = Att = Physical Address
556 // 0b00 = Normal Memory
557 // 0b01 = SAO
558 // 0b10 = Non Idenmpotent
559 // 0b11 = Tolerant I/O
560 // [60:63] = Encoded Access
561 // Authority
562 //
563 -- test leaf bit
564 -- check permissions and RC bits
565 perm_ok := '0';
566 if r.priv = '1' or data(3) = '0' then
567 if r.iside = '0' then
568 perm_ok := data(1) or (data(2) and not r.store);
569 else
570 -- no IAMR, so no KUEP support for now
571 -- deny execute permission if cache inhibited
572 perm_ok := data(0) and not data(5);
573 end if;
574 end if;
575 rc_ok := data(8) and (data(7) or not r.store);
576 if perm_ok = '1' and rc_ok = '1' then
577 v.state := RADIX_LOAD_TLB;
578 else
579 v.state := RADIX_FINISH;
580 v.perm_err := not perm_ok;
581 -- permission error takes precedence over RC error
582 v.rc_error := perm_ok;
583 end if;
584 """
585 # decode mode into something that matches microwatt equivalent code
586 instr_fetch, store = 0, 0
587 if mode == 'STORE':
588 store = 1
589 if mode == 'EXECUTE':
590 inst_fetch = 1
591
592 # check permissions and RC bits
593 perm_ok = 0
594 if priv == 1 or data[60] == 0:
595 if instr_fetch == 0:
596 perm_ok = data[62] | (data[61] & (store == 0))
597 # no IAMR, so no KUEP support for now
598 # deny execute permission if cache inhibited
599 perm_ok = data[63] & ~data[58]
600 rc_ok = data[55] & (data[56] | (store == 0))
601 if perm_ok == 1 and rc_ok == 1:
602 return True
603
604 return "perm_err" if perm_ok == 0 else "rc_err"
605
606 def _get_prtable_addr(self, shift, prtbl, addr, pid):
607 """
608 if r.addr(63) = '1' then
609 effpid := x"00000000";
610 else
611 effpid := r.pid;
612 end if;
613 x"00" & r.prtbl(55 downto 36) &
614 ((r.prtbl(35 downto 12) and not finalmask(23 downto 0)) or
615 (effpid(31 downto 8) and finalmask(23 downto 0))) &
616 effpid(7 downto 0) & "0000";
617 """
618 print ("_get_prtable_addr", shift, prtbl, addr, pid)
619 finalmask = genmask(shift, 44)
620 finalmask24 = finalmask[20:44]
621 if addr[0].value == 1:
622 effpid = SelectableInt(0, 32)
623 else:
624 effpid = pid #self.pid # TODO, check on this
625 zero8 = SelectableInt(0, 8)
626 zero4 = SelectableInt(0, 4)
627 res = selectconcat(zero8,
628 prtbl[8:28], #
629 (prtbl[28:52] & ~finalmask24) | #
630 (effpid[0:24] & finalmask24), #
631 effpid[24:32],
632 zero4
633 )
634 return res
635
636 def _get_pgtable_addr(self, mask_size, pgbase, addrsh):
637 """
638 x"00" & r.pgbase(55 downto 19) &
639 ((r.pgbase(18 downto 3) and not mask) or (addrsh and mask)) &
640 "000";
641 """
642 mask16 = genmask(mask_size+5, 16)
643 zero8 = SelectableInt(0, 8)
644 zero3 = SelectableInt(0, 3)
645 res = selectconcat(zero8,
646 pgbase[8:45], #
647 (pgbase[45:61] & ~mask16) | #
648 (addrsh & mask16), #
649 zero3
650 )
651 return res
652
653 def _get_pte(self, shift, addr, pde):
654 """
655 x"00" &
656 ((r.pde(55 downto 12) and not finalmask) or
657 (r.addr(55 downto 12) and finalmask))
658 & r.pde(11 downto 0);
659 """
660 shift.value = 12
661 finalmask = genmask(shift, 44)
662 zero8 = SelectableInt(0, 8)
663 rpn = pde[8:52] # RPN = Real Page Number
664 abits = addr[8:52] # non-masked address bits
665 print(" get_pte RPN", hex(rpn.value))
666 print(" abits", hex(abits.value))
667 print(" shift", shift.value)
668 print(" finalmask", bin(finalmask.value))
669 res = selectconcat(zero8,
670 (rpn & ~finalmask) | #
671 (abits & finalmask), #
672 addr[52:64],
673 )
674 return res
675
676 class TestRadixMMU(unittest.TestCase):
677
678 def test_genmask(self):
679 shift = SelectableInt(5, 6)
680 mask = genmask(shift, 43)
681 print (" mask", bin(mask.value))
682
683 self.assertEqual(mask.value, 0b11111, "mask should be 5 1s")
684
685 def test_get_pgtable_addr(self):
686
687 mem = None
688 caller = None
689 dut = RADIX(mem, caller)
690
691 mask_size=4
692 pgbase = SelectableInt(0,64)
693 addrsh = SelectableInt(0,16)
694 ret = dut._get_pgtable_addr(mask_size, pgbase, addrsh)
695 print("ret=", ret)
696 self.assertEqual(ret, 0, "pgtbl_addr should be 0")
697
698 def test_prtable_lookup(self):
699
700 mem = None
701 caller = None
702 dut = RADIX(mem, caller)
703
704 prtbl = SelectableInt(0x1000000,64)
705 addr = SelectableInt(0, 64)
706 pid = SelectableInt(0, 64)
707 ret = dut._prtable_lookup(prtbl, addr, pid)
708
709 def test_walk_tree_1(self):
710
711 # test address as in
712 # https://github.com/power-gem5/gem5/blob/gem5-experimental/src/arch/power/radix_walk_example.txt#L65
713 testaddr = 0x1000
714 expected = 0x1000
715
716 # set up dummy minimal ISACaller
717 spr = {'DSISR': SelectableInt(0, 64),
718 'DAR': SelectableInt(0, 64),
719 'PIDR': SelectableInt(0, 64),
720 'PRTBL': SelectableInt(0, 64)
721 }
722 # set problem state == 0 (other unit tests, set to 1)
723 msr = SelectableInt(0, 64)
724 msr[MSRb.PR] = 0
725 class ISACaller: pass
726 caller = ISACaller()
727 caller.spr = spr
728 caller.msr = msr
729
730 shift = SelectableInt(5, 6)
731 mask = genmask(shift, 43)
732 print (" mask", bin(mask.value))
733
734 mem = Mem(row_bytes=8, initial_mem=testmem)
735 mem = RADIX(mem, caller)
736 # -----------------------------------------------
737 # |/|RTS1|/| RPDB | RTS2 | RPDS |
738 # -----------------------------------------------
739 # |0|1 2|3|4 55|56 58|59 63|
740 data = SelectableInt(0, 64)
741 data[1:3] = 0b01
742 data[56:59] = 0b11
743 data[59:64] = 0b01101 # mask
744 data[55] = 1
745 (rts, mbits, pgbase) = mem._decode_prte(data)
746 print (" rts", bin(rts.value), rts.bits)
747 print (" mbits", bin(mbits.value), mbits.bits)
748 print (" pgbase", hex(pgbase.value), pgbase.bits)
749 addr = SelectableInt(0x1000, 64)
750 check = mem._segment_check(addr, mbits, shift)
751 print (" segment check", check)
752
753 print("walking tree")
754 addr = SelectableInt(testaddr,64)
755 # pgbase = None
756 mode = None
757 #mbits = None
758 shift = rts
759 result = mem._walk_tree(addr, pgbase, mode, mbits, shift)
760 print(" walking tree result", result)
761 print("should be", testresult)
762 self.assertEqual(result.value, expected,
763 "expected 0x%x got 0x%x" % (expected,
764 result.value))
765
766
767 def test_walk_tree_2(self):
768
769 # test address slightly different
770 testaddr = 0x1101
771 expected = 0x5001101
772
773 # set up dummy minimal ISACaller
774 spr = {'DSISR': SelectableInt(0, 64),
775 'DAR': SelectableInt(0, 64),
776 'PIDR': SelectableInt(0, 64),
777 'PRTBL': SelectableInt(0, 64)
778 }
779 # set problem state == 0 (other unit tests, set to 1)
780 msr = SelectableInt(0, 64)
781 msr[MSRb.PR] = 0
782 class ISACaller: pass
783 caller = ISACaller()
784 caller.spr = spr
785 caller.msr = msr
786
787 shift = SelectableInt(5, 6)
788 mask = genmask(shift, 43)
789 print (" mask", bin(mask.value))
790
791 mem = Mem(row_bytes=8, initial_mem=testmem2)
792 mem = RADIX(mem, caller)
793 # -----------------------------------------------
794 # |/|RTS1|/| RPDB | RTS2 | RPDS |
795 # -----------------------------------------------
796 # |0|1 2|3|4 55|56 58|59 63|
797 data = SelectableInt(0, 64)
798 data[1:3] = 0b01
799 data[56:59] = 0b11
800 data[59:64] = 0b01101 # mask
801 data[55] = 1
802 (rts, mbits, pgbase) = mem._decode_prte(data)
803 print (" rts", bin(rts.value), rts.bits)
804 print (" mbits", bin(mbits.value), mbits.bits)
805 print (" pgbase", hex(pgbase.value), pgbase.bits)
806 addr = SelectableInt(0x1000, 64)
807 check = mem._segment_check(addr, mbits, shift)
808 print (" segment check", check)
809
810 print("walking tree")
811 addr = SelectableInt(testaddr,64)
812 # pgbase = None
813 mode = None
814 #mbits = None
815 shift = rts
816 result = mem._walk_tree(addr, pgbase, mode, mbits, shift)
817 print(" walking tree result", result)
818 print("should be", testresult)
819 self.assertEqual(result.value, expected,
820 "expected 0x%x got 0x%x" % (expected,
821 result.value))
822
823
824 if __name__ == '__main__':
825 unittest.main()