3 based on Anton Blanchard microwatt dcache.vhdl
5 note that the microwatt dcache wishbone interface expects "stall".
6 for simplicity at the moment this is hard-coded to cyc & ~ack.
7 see WB4 spec, p84, section 5.2.1
9 IMPORTANT: for store, the data is sampled the cycle AFTER the "valid"
14 * https://libre-soc.org/3d_gpu/architecture/set_associative_cache.jpg
15 * https://bugs.libre-soc.org/show_bug.cgi?id=469
21 from nmutil
.gtkw
import write_gtkw
23 sys
.setrecursionlimit(1000000)
25 from enum
import Enum
, unique
27 from nmigen
import (Module
, Signal
, Elaboratable
, Cat
, Repl
, Array
, Const
,
29 from nmutil
.util
import Display
31 from copy
import deepcopy
32 from random
import randint
, seed
34 from nmigen_soc
.wishbone
.bus
import Interface
36 from nmigen
.cli
import main
37 from nmutil
.iocontrol
import RecordObject
38 from nmigen
.utils
import log2_int
39 from soc
.experiment
.mem_types
import (LoadStore1ToDCacheType
,
40 DCacheToLoadStore1Type
,
44 from soc
.experiment
.wb_types
import (WB_ADDR_BITS
, WB_DATA_BITS
, WB_SEL_BITS
,
45 WBAddrType
, WBDataType
, WBSelType
,
46 WBMasterOut
, WBSlaveOut
,
47 WBMasterOutVector
, WBSlaveOutVector
,
48 WBIOMasterOut
, WBIOSlaveOut
)
50 from soc
.experiment
.cache_ram
import CacheRam
51 #from soc.experiment.plru import PLRU
52 from nmutil
.plru
import PLRU
55 from soc
.bus
.sram
import SRAM
56 from nmigen
import Memory
57 from nmigen
.cli
import rtlil
59 # NOTE: to use cxxsim, export NMIGEN_SIM_MODE=cxxsim from the shell
60 # Also, check out the cxxsim nmigen branch, and latest yosys from git
61 from nmutil
.sim_tmp_alternative
import Simulator
63 from nmutil
.util
import wrap
66 # TODO: make these parameters of DCache at some point
67 LINE_SIZE
= 64 # Line size in bytes
68 NUM_LINES
= 16 # Number of lines in a set
69 NUM_WAYS
= 4 # Number of ways
70 TLB_SET_SIZE
= 64 # L1 DTLB entries per set
71 TLB_NUM_WAYS
= 2 # L1 DTLB number of sets
72 TLB_LG_PGSZ
= 12 # L1 DTLB log_2(page_size)
73 LOG_LENGTH
= 0 # Non-zero to enable log data collection
75 # BRAM organisation: We never access more than
76 # -- WB_DATA_BITS at a time so to save
77 # -- resources we make the array only that wide, and
78 # -- use consecutive indices to make a cache "line"
80 # -- ROW_SIZE is the width in bytes of the BRAM
81 # -- (based on WB, so 64-bits)
82 ROW_SIZE
= WB_DATA_BITS
// 8;
84 # ROW_PER_LINE is the number of row (wishbone
85 # transactions) in a line
86 ROW_PER_LINE
= LINE_SIZE
// ROW_SIZE
88 # BRAM_ROWS is the number of rows in BRAM needed
89 # to represent the full dcache
90 BRAM_ROWS
= NUM_LINES
* ROW_PER_LINE
92 print ("ROW_SIZE", ROW_SIZE
)
93 print ("ROW_PER_LINE", ROW_PER_LINE
)
94 print ("BRAM_ROWS", BRAM_ROWS
)
95 print ("NUM_WAYS", NUM_WAYS
)
97 # Bit fields counts in the address
99 # REAL_ADDR_BITS is the number of real address
103 # ROW_BITS is the number of bits to select a row
104 ROW_BITS
= log2_int(BRAM_ROWS
)
106 # ROW_LINE_BITS is the number of bits to select
107 # a row within a line
108 ROW_LINE_BITS
= log2_int(ROW_PER_LINE
)
110 # LINE_OFF_BITS is the number of bits for
111 # the offset in a cache line
112 LINE_OFF_BITS
= log2_int(LINE_SIZE
)
114 # ROW_OFF_BITS is the number of bits for
115 # the offset in a row
116 ROW_OFF_BITS
= log2_int(ROW_SIZE
)
118 # INDEX_BITS is the number if bits to
119 # select a cache line
120 INDEX_BITS
= log2_int(NUM_LINES
)
122 # SET_SIZE_BITS is the log base 2 of the set size
123 SET_SIZE_BITS
= LINE_OFF_BITS
+ INDEX_BITS
125 # TAG_BITS is the number of bits of
126 # the tag part of the address
127 TAG_BITS
= REAL_ADDR_BITS
- SET_SIZE_BITS
129 # TAG_WIDTH is the width in bits of each way of the tag RAM
130 TAG_WIDTH
= TAG_BITS
+ 7 - ((TAG_BITS
+ 7) % 8)
132 # WAY_BITS is the number of bits to select a way
133 WAY_BITS
= log2_int(NUM_WAYS
)
135 # Example of layout for 32 lines of 64 bytes:
137 .. tag |index| line |
139 .. | |---| | ROW_LINE_BITS (3)
140 .. | |--- - --| LINE_OFF_BITS (6)
141 .. | |- --| ROW_OFF_BITS (3)
142 .. |----- ---| | ROW_BITS (8)
143 .. |-----| | INDEX_BITS (5)
144 .. --------| | TAG_BITS (45)
147 print ("Dcache TAG %d IDX %d ROW_BITS %d ROFF %d LOFF %d RLB %d" % \
148 (TAG_BITS
, INDEX_BITS
, ROW_BITS
,
149 ROW_OFF_BITS
, LINE_OFF_BITS
, ROW_LINE_BITS
))
150 print ("index @: %d-%d" % (LINE_OFF_BITS
, SET_SIZE_BITS
))
151 print ("row @: %d-%d" % (LINE_OFF_BITS
, ROW_OFF_BITS
))
152 print ("tag @: %d-%d width %d" % (SET_SIZE_BITS
, REAL_ADDR_BITS
, TAG_WIDTH
))
154 TAG_RAM_WIDTH
= TAG_WIDTH
* NUM_WAYS
156 print ("TAG_RAM_WIDTH", TAG_RAM_WIDTH
)
159 tag_layout
= [('valid', 1),
160 ('tag', TAG_RAM_WIDTH
),
162 return Array(Record(tag_layout
, name
="tag%d" % x
) for x
in range(NUM_LINES
))
164 def RowPerLineValidArray():
165 return Array(Signal(name
="rows_valid%d" % x
) \
166 for x
in range(ROW_PER_LINE
))
169 TLB_SET_BITS
= log2_int(TLB_SET_SIZE
)
170 TLB_WAY_BITS
= log2_int(TLB_NUM_WAYS
)
171 TLB_EA_TAG_BITS
= 64 - (TLB_LG_PGSZ
+ TLB_SET_BITS
)
172 TLB_TAG_WAY_BITS
= TLB_NUM_WAYS
* TLB_EA_TAG_BITS
174 TLB_PTE_WAY_BITS
= TLB_NUM_WAYS
* TLB_PTE_BITS
;
177 return (1<<log2_int(x
, False)) == x
179 assert (LINE_SIZE
% ROW_SIZE
) == 0, "LINE_SIZE not multiple of ROW_SIZE"
180 assert ispow2(LINE_SIZE
), "LINE_SIZE not power of 2"
181 assert ispow2(NUM_LINES
), "NUM_LINES not power of 2"
182 assert ispow2(ROW_PER_LINE
), "ROW_PER_LINE not power of 2"
183 assert ROW_BITS
== (INDEX_BITS
+ ROW_LINE_BITS
), "geometry bits don't add up"
184 assert (LINE_OFF_BITS
== ROW_OFF_BITS
+ ROW_LINE_BITS
), \
185 "geometry bits don't add up"
186 assert REAL_ADDR_BITS
== (TAG_BITS
+ INDEX_BITS
+ LINE_OFF_BITS
), \
187 "geometry bits don't add up"
188 assert REAL_ADDR_BITS
== (TAG_BITS
+ ROW_BITS
+ ROW_OFF_BITS
), \
189 "geometry bits don't add up"
190 assert 64 == WB_DATA_BITS
, "Can't yet handle wb width that isn't 64-bits"
191 assert SET_SIZE_BITS
<= TLB_LG_PGSZ
, "Set indexed by virtual address"
194 return Record([('valid', 1),
195 ('way', TLB_WAY_BITS
)], name
=name
)
198 return Array(Signal(TLB_EA_TAG_BITS
, name
="tlbtagea%d" % x
) \
199 for x
in range (TLB_NUM_WAYS
))
202 tlb_layout
= [('valid', TLB_NUM_WAYS
),
203 ('tag', TLB_TAG_WAY_BITS
),
204 ('pte', TLB_PTE_WAY_BITS
)
206 return Record(tlb_layout
, name
=name
)
209 return Array(TLBRecord(name
="tlb%d" % x
) for x
in range(TLB_SET_SIZE
))
212 return Array(Signal(WAY_BITS
, name
="hitway_%d" % x
) \
213 for x
in range(TLB_NUM_WAYS
))
215 # Cache RAM interface
217 return Array(Signal(WB_DATA_BITS
, name
="cache_out%d" % x
) \
218 for x
in range(NUM_WAYS
))
220 # PLRU output interface
222 return Array(Signal(WAY_BITS
, name
="plru_out%d" % x
) \
223 for x
in range(NUM_LINES
))
225 # TLB PLRU output interface
227 return Array(Signal(TLB_WAY_BITS
, name
="tlbplru_out%d" % x
) \
228 for x
in range(TLB_SET_SIZE
))
230 # Helper functions to decode incoming requests
232 # Return the cache line index (tag index) for an address
234 return addr
[LINE_OFF_BITS
:SET_SIZE_BITS
]
236 # Return the cache row index (data memory) for an address
238 return addr
[ROW_OFF_BITS
:SET_SIZE_BITS
]
240 # Return the index of a row within a line
241 def get_row_of_line(row
):
242 return row
[:ROW_BITS
][:ROW_LINE_BITS
]
244 # Returns whether this is the last row of a line
245 def is_last_row_addr(addr
, last
):
246 return addr
[ROW_OFF_BITS
:LINE_OFF_BITS
] == last
248 # Returns whether this is the last row of a line
249 def is_last_row(row
, last
):
250 return get_row_of_line(row
) == last
252 # Return the next row in the current cache line. We use a
253 # dedicated function in order to limit the size of the
254 # generated adder to be only the bits within a cache line
255 # (3 bits with default settings)
257 row_v
= row
[0:ROW_LINE_BITS
] + 1
258 return Cat(row_v
[:ROW_LINE_BITS
], row
[ROW_LINE_BITS
:])
260 # Get the tag value from the address
262 return addr
[SET_SIZE_BITS
:REAL_ADDR_BITS
]
264 # Read a tag from a tag memory row
265 def read_tag(way
, tagset
):
266 return tagset
.word_select(way
, TAG_WIDTH
)[:TAG_BITS
]
268 # Read a TLB tag from a TLB tag memory row
269 def read_tlb_tag(way
, tags
):
270 return tags
.word_select(way
, TLB_EA_TAG_BITS
)
272 # Write a TLB tag to a TLB tag memory row
273 def write_tlb_tag(way
, tags
, tag
):
274 return read_tlb_tag(way
, tags
).eq(tag
)
276 # Read a PTE from a TLB PTE memory row
277 def read_tlb_pte(way
, ptes
):
278 return ptes
.word_select(way
, TLB_PTE_BITS
)
280 def write_tlb_pte(way
, ptes
, newpte
):
281 return read_tlb_pte(way
, ptes
).eq(newpte
)
284 # Record for storing permission, attribute, etc. bits from a PTE
285 class PermAttr(RecordObject
):
286 def __init__(self
, name
=None):
287 super().__init
__(name
=name
)
288 self
.reference
= Signal()
289 self
.changed
= Signal()
290 self
.nocache
= Signal()
292 self
.rd_perm
= Signal()
293 self
.wr_perm
= Signal()
296 def extract_perm_attr(pte
):
301 # Type of operation on a "valid" input
305 OP_BAD
= 1 # NC cache hit, TLB miss, prot/RC failure
306 OP_STCX_FAIL
= 2 # conditional store w/o reservation
307 OP_LOAD_HIT
= 3 # Cache hit on load
308 OP_LOAD_MISS
= 4 # Load missing cache
309 OP_LOAD_NC
= 5 # Non-cachable load
310 OP_STORE_HIT
= 6 # Store hitting cache
311 OP_STORE_MISS
= 7 # Store missing cache
314 # Cache state machine
317 IDLE
= 0 # Normal load hit processing
318 RELOAD_WAIT_ACK
= 1 # Cache reload wait ack
319 STORE_WAIT_ACK
= 2 # Store wait ack
320 NC_LOAD_WAIT_ACK
= 3 # Non-cachable load wait ack
325 # In order to make timing, we use the BRAMs with
326 # an output buffer, which means that the BRAM
327 # output is delayed by an extra cycle.
329 # Thus, the dcache has a 2-stage internal pipeline
330 # for cache hits with no stalls.
332 # All other operations are handled via stalling
333 # in the first stage.
335 # The second stage can thus complete a hit at the same
336 # time as the first stage emits a stall for a complex op.
338 # Stage 0 register, basically contains just the latched request
340 class RegStage0(RecordObject
):
341 def __init__(self
, name
=None):
342 super().__init
__(name
=name
)
343 self
.req
= LoadStore1ToDCacheType(name
="lsmem")
344 self
.tlbie
= Signal() # indicates a tlbie request (from MMU)
345 self
.doall
= Signal() # with tlbie, indicates flush whole TLB
346 self
.tlbld
= Signal() # indicates a TLB load request (from MMU)
347 self
.mmu_req
= Signal() # indicates source of request
348 self
.d_valid
= Signal() # indicates req.data is valid now
351 class MemAccessRequest(RecordObject
):
352 def __init__(self
, name
=None):
353 super().__init
__(name
=name
)
355 self
.valid
= Signal()
357 self
.real_addr
= Signal(REAL_ADDR_BITS
)
358 self
.data
= Signal(64)
359 self
.byte_sel
= Signal(8)
360 self
.hit_way
= Signal(WAY_BITS
)
361 self
.same_tag
= Signal()
362 self
.mmu_req
= Signal()
365 # First stage register, contains state for stage 1 of load hits
366 # and for the state machine used by all other operations
367 class RegStage1(RecordObject
):
368 def __init__(self
, name
=None):
369 super().__init
__(name
=name
)
370 # Info about the request
371 self
.full
= Signal() # have uncompleted request
372 self
.mmu_req
= Signal() # request is from MMU
373 self
.req
= MemAccessRequest(name
="reqmem")
376 self
.hit_way
= Signal(WAY_BITS
)
377 self
.hit_load_valid
= Signal()
378 self
.hit_index
= Signal(INDEX_BITS
)
379 self
.cache_hit
= Signal()
382 self
.tlb_hit
= TLBHit("tlb_hit")
383 self
.tlb_hit_index
= Signal(TLB_SET_BITS
)
385 # 2-stage data buffer for data forwarded from writes to reads
386 self
.forward_data1
= Signal(64)
387 self
.forward_data2
= Signal(64)
388 self
.forward_sel1
= Signal(8)
389 self
.forward_valid1
= Signal()
390 self
.forward_way1
= Signal(WAY_BITS
)
391 self
.forward_row1
= Signal(ROW_BITS
)
392 self
.use_forward1
= Signal()
393 self
.forward_sel
= Signal(8)
395 # Cache miss state (reload state machine)
396 self
.state
= Signal(State
)
398 self
.write_bram
= Signal()
399 self
.write_tag
= Signal()
400 self
.slow_valid
= Signal()
401 self
.wb
= WBMasterOut("wb")
402 self
.reload_tag
= Signal(TAG_BITS
)
403 self
.store_way
= Signal(WAY_BITS
)
404 self
.store_row
= Signal(ROW_BITS
)
405 self
.store_index
= Signal(INDEX_BITS
)
406 self
.end_row_ix
= Signal(ROW_LINE_BITS
)
407 self
.rows_valid
= RowPerLineValidArray()
408 self
.acks_pending
= Signal(3)
409 self
.inc_acks
= Signal()
410 self
.dec_acks
= Signal()
412 # Signals to complete (possibly with error)
413 self
.ls_valid
= Signal()
414 self
.ls_error
= Signal()
415 self
.mmu_done
= Signal()
416 self
.mmu_error
= Signal()
417 self
.cache_paradox
= Signal()
419 # Signal to complete a failed stcx.
420 self
.stcx_fail
= Signal()
423 # Reservation information
424 class Reservation(RecordObject
):
427 self
.valid
= Signal()
428 self
.addr
= Signal(64-LINE_OFF_BITS
)
431 class DTLBUpdate(Elaboratable
):
433 self
.tlbie
= Signal()
434 self
.tlbwe
= Signal()
435 self
.doall
= Signal()
436 self
.updated
= Signal()
437 self
.v_updated
= Signal()
438 self
.tlb_hit
= TLBHit("tlb_hit")
439 self
.tlb_req_index
= Signal(TLB_SET_BITS
)
441 self
.tlb_tag_way
= Signal(TLB_TAG_WAY_BITS
)
442 self
.tlb_pte_way
= Signal(TLB_PTE_WAY_BITS
)
443 self
.repl_way
= Signal(TLB_WAY_BITS
)
444 self
.eatag
= Signal(TLB_EA_TAG_BITS
)
445 self
.pte_data
= Signal(TLB_PTE_BITS
)
447 self
.dv
= Signal(TLB_NUM_WAYS
) # tlb_way_valids_t
449 self
.tb_out
= Signal(TLB_TAG_WAY_BITS
) # tlb_way_tags_t
450 self
.db_out
= Signal(TLB_NUM_WAYS
) # tlb_way_valids_t
451 self
.pb_out
= Signal(TLB_PTE_WAY_BITS
) # tlb_way_ptes_t
453 def elaborate(self
, platform
):
458 tagset
= Signal(TLB_TAG_WAY_BITS
)
459 pteset
= Signal(TLB_PTE_WAY_BITS
)
461 tb_out
, pb_out
, db_out
= self
.tb_out
, self
.pb_out
, self
.db_out
462 comb
+= db_out
.eq(self
.dv
)
464 with m
.If(self
.tlbie
& self
.doall
):
465 pass # clear all back in parent
466 with m
.Elif(self
.tlbie
):
467 with m
.If(self
.tlb_hit
.valid
):
468 comb
+= db_out
.bit_select(self
.tlb_hit
.way
, 1).eq(0)
469 comb
+= self
.v_updated
.eq(1)
471 with m
.Elif(self
.tlbwe
):
473 comb
+= tagset
.eq(self
.tlb_tag_way
)
474 comb
+= write_tlb_tag(self
.repl_way
, tagset
, self
.eatag
)
475 comb
+= tb_out
.eq(tagset
)
477 comb
+= pteset
.eq(self
.tlb_pte_way
)
478 comb
+= write_tlb_pte(self
.repl_way
, pteset
, self
.pte_data
)
479 comb
+= pb_out
.eq(pteset
)
481 comb
+= db_out
.bit_select(self
.repl_way
, 1).eq(1)
483 comb
+= self
.updated
.eq(1)
484 comb
+= self
.v_updated
.eq(1)
489 class DCachePendingHit(Elaboratable
):
491 def __init__(self
, tlb_way
,
492 cache_i_validdx
, cache_tag_set
,
497 self
.virt_mode
= Signal()
498 self
.is_hit
= Signal()
499 self
.tlb_hit
= TLBHit("tlb_hit")
500 self
.hit_way
= Signal(WAY_BITS
)
501 self
.rel_match
= Signal()
502 self
.req_index
= Signal(INDEX_BITS
)
503 self
.reload_tag
= Signal(TAG_BITS
)
505 self
.tlb_way
= tlb_way
506 self
.cache_i_validdx
= cache_i_validdx
507 self
.cache_tag_set
= cache_tag_set
508 self
.req_addr
= req_addr
509 self
.hit_set
= hit_set
511 def elaborate(self
, platform
):
517 virt_mode
= self
.virt_mode
519 tlb_way
= self
.tlb_way
520 cache_i_validdx
= self
.cache_i_validdx
521 cache_tag_set
= self
.cache_tag_set
522 req_addr
= self
.req_addr
523 tlb_hit
= self
.tlb_hit
524 hit_set
= self
.hit_set
525 hit_way
= self
.hit_way
526 rel_match
= self
.rel_match
527 req_index
= self
.req_index
528 reload_tag
= self
.reload_tag
530 rel_matches
= Array(Signal(name
="rel_matches_%d" % i
) \
531 for i
in range(TLB_NUM_WAYS
))
532 hit_way_set
= HitWaySet()
534 # Test if pending request is a hit on any way
535 # In order to make timing in virtual mode,
536 # when we are using the TLB, we compare each
537 # way with each of the real addresses from each way of
538 # the TLB, and then decide later which match to use.
540 with m
.If(virt_mode
):
541 for j
in range(TLB_NUM_WAYS
): # tlb_num_way_t
542 s_tag
= Signal(TAG_BITS
, name
="s_tag%d" % j
)
544 s_pte
= Signal(TLB_PTE_BITS
)
545 s_ra
= Signal(REAL_ADDR_BITS
)
546 comb
+= s_pte
.eq(read_tlb_pte(j
, tlb_way
.pte
))
547 comb
+= s_ra
.eq(Cat(req_addr
[0:TLB_LG_PGSZ
],
548 s_pte
[TLB_LG_PGSZ
:REAL_ADDR_BITS
]))
549 comb
+= s_tag
.eq(get_tag(s_ra
))
551 for i
in range(NUM_WAYS
): # way_t
552 is_tag_hit
= Signal(name
="is_tag_hit_%d_%d" % (j
, i
))
553 comb
+= is_tag_hit
.eq(go
& cache_i_validdx
[i
] &
554 (read_tag(i
, cache_tag_set
) == s_tag
)
555 & (tlb_way
.valid
[j
]))
556 with m
.If(is_tag_hit
):
557 comb
+= hit_way_set
[j
].eq(i
)
559 comb
+= hit_set
[j
].eq(s_hit
)
560 with m
.If(s_tag
== reload_tag
):
561 comb
+= rel_matches
[j
].eq(1)
562 with m
.If(tlb_hit
.way
):
563 comb
+= is_hit
.eq(hit_set
[tlb_hit
.way
])
564 comb
+= hit_way
.eq(hit_way_set
[tlb_hit
.way
])
565 comb
+= rel_match
.eq(rel_matches
[tlb_hit
.way
])
567 s_tag
= Signal(TAG_BITS
)
568 comb
+= s_tag
.eq(get_tag(req_addr
))
569 for i
in range(NUM_WAYS
): # way_t
570 is_tag_hit
= Signal(name
="is_tag_hit_%d" % i
)
571 comb
+= is_tag_hit
.eq(go
& cache_i_validdx
[i
] &
572 (read_tag(i
, cache_tag_set
) == s_tag
))
573 with m
.If(is_tag_hit
):
574 comb
+= hit_way
.eq(i
)
576 with m
.If(s_tag
== reload_tag
):
577 comb
+= rel_match
.eq(1)
582 class DCache(Elaboratable
):
583 """Set associative dcache write-through
585 TODO (in no specific order):
586 * See list in icache.vhdl
587 * Complete load misses on the cycle when WB data comes instead of
588 at the end of line (this requires dealing with requests coming in
592 self
.d_in
= LoadStore1ToDCacheType("d_in")
593 self
.d_out
= DCacheToLoadStore1Type("d_out")
595 self
.m_in
= MMUToDCacheType("m_in")
596 self
.m_out
= DCacheToMMUType("m_out")
598 self
.stall_out
= Signal()
600 # standard naming (wired to non-standard for compatibility)
601 self
.bus
= Interface(addr_width
=32,
608 self
.log_out
= Signal(20)
610 def stage_0(self
, m
, r0
, r1
, r0_full
):
611 """Latch the request in r0.req as long as we're not stalling
615 d_in
, d_out
, m_in
= self
.d_in
, self
.d_out
, self
.m_in
617 r
= RegStage0("stage0")
619 # TODO, this goes in unit tests and formal proofs
620 with m
.If(d_in
.valid
& m_in
.valid
):
621 sync
+= Display("request collision loadstore vs MMU")
623 with m
.If(m_in
.valid
):
624 comb
+= r
.req
.valid
.eq(1)
625 comb
+= r
.req
.load
.eq(~
(m_in
.tlbie | m_in
.tlbld
))# no invalidate
626 comb
+= r
.req
.dcbz
.eq(0)
627 comb
+= r
.req
.nc
.eq(0)
628 comb
+= r
.req
.reserve
.eq(0)
629 comb
+= r
.req
.virt_mode
.eq(0)
630 comb
+= r
.req
.priv_mode
.eq(1)
631 comb
+= r
.req
.addr
.eq(m_in
.addr
)
632 comb
+= r
.req
.data
.eq(m_in
.pte
)
633 comb
+= r
.req
.byte_sel
.eq(~
0) # Const -1 sets all to 0b111....
634 comb
+= r
.tlbie
.eq(m_in
.tlbie
)
635 comb
+= r
.doall
.eq(m_in
.doall
)
636 comb
+= r
.tlbld
.eq(m_in
.tlbld
)
637 comb
+= r
.mmu_req
.eq(1)
638 m
.d
.sync
+= Display(" DCACHE req mmu addr %x pte %x ld %d",
639 m_in
.addr
, m_in
.pte
, r
.req
.load
)
642 comb
+= r
.req
.eq(d_in
)
643 comb
+= r
.req
.data
.eq(0)
644 comb
+= r
.tlbie
.eq(0)
645 comb
+= r
.doall
.eq(0)
646 comb
+= r
.tlbld
.eq(0)
647 comb
+= r
.mmu_req
.eq(0)
648 with m
.If((~r1
.full
& ~d_in
.hold
) | ~r0_full
):
650 sync
+= r0_full
.eq(r
.req
.valid
)
651 # Sample data the cycle after a request comes in from loadstore1.
652 # If another request has come in already then the data will get
653 # put directly into req.data below.
654 with m
.If(r0
.req
.valid
& ~r
.req
.valid
& ~r0
.d_valid
&
656 sync
+= r0
.req
.data
.eq(d_in
.data
)
657 sync
+= r0
.d_valid
.eq(1)
658 with m
.If(d_in
.valid
):
659 m
.d
.sync
+= Display(" DCACHE req cache "
660 "virt %d addr %x data %x ld %d",
661 r
.req
.virt_mode
, r
.req
.addr
,
662 r
.req
.data
, r
.req
.load
)
664 def tlb_read(self
, m
, r0_stall
, tlb_way
, dtlb
):
666 Operates in the second cycle on the request latched in r0.req.
667 TLB updates write the entry at the end of the second cycle.
671 m_in
, d_in
= self
.m_in
, self
.d_in
673 index
= Signal(TLB_SET_BITS
)
674 addrbits
= Signal(TLB_SET_BITS
)
677 amax
= TLB_LG_PGSZ
+ TLB_SET_BITS
679 with m
.If(m_in
.valid
):
680 comb
+= addrbits
.eq(m_in
.addr
[amin
: amax
])
682 comb
+= addrbits
.eq(d_in
.addr
[amin
: amax
])
683 comb
+= index
.eq(addrbits
)
685 # If we have any op and the previous op isn't finished,
686 # then keep the same output for next cycle.
687 with m
.If(~r0_stall
):
688 sync
+= tlb_way
.eq(dtlb
[index
])
690 def maybe_tlb_plrus(self
, m
, r1
, tlb_plru_victim
):
691 """Generate TLB PLRUs
696 if TLB_NUM_WAYS
== 0:
698 for i
in range(TLB_SET_SIZE
):
700 tlb_plru
= PLRU(TLB_WAY_BITS
)
701 setattr(m
.submodules
, "maybe_plru_%d" % i
, tlb_plru
)
702 tlb_plru_acc_en
= Signal()
704 comb
+= tlb_plru_acc_en
.eq(r1
.tlb_hit
.valid
&
705 (r1
.tlb_hit_index
== i
))
706 comb
+= tlb_plru
.acc_en
.eq(tlb_plru_acc_en
)
707 comb
+= tlb_plru
.acc_i
.eq(r1
.tlb_hit
.way
)
708 comb
+= tlb_plru_victim
[i
].eq(tlb_plru
.lru_o
)
710 def tlb_search(self
, m
, tlb_req_index
, r0
, r0_valid
,
712 pte
, tlb_hit
, valid_ra
, perm_attr
, ra
):
716 hitway
= Signal(TLB_WAY_BITS
)
718 eatag
= Signal(TLB_EA_TAG_BITS
)
720 TLB_LG_END
= TLB_LG_PGSZ
+ TLB_SET_BITS
721 comb
+= tlb_req_index
.eq(r0
.req
.addr
[TLB_LG_PGSZ
: TLB_LG_END
])
722 comb
+= eatag
.eq(r0
.req
.addr
[TLB_LG_END
: 64 ])
724 for i
in range(TLB_NUM_WAYS
):
725 is_tag_hit
= Signal(name
="is_tag_hit%d" % i
)
726 tlb_tag
= Signal(TLB_EA_TAG_BITS
, name
="tlb_tag%d" % i
)
727 comb
+= tlb_tag
.eq(read_tlb_tag(i
, tlb_way
.tag
))
728 comb
+= is_tag_hit
.eq((tlb_way
.valid
[i
]) & (tlb_tag
== eatag
))
729 with m
.If(is_tag_hit
):
733 comb
+= tlb_hit
.valid
.eq(hit
& r0_valid
)
734 comb
+= tlb_hit
.way
.eq(hitway
)
736 with m
.If(tlb_hit
.valid
):
737 comb
+= pte
.eq(read_tlb_pte(hitway
, tlb_way
.pte
))
738 comb
+= valid_ra
.eq(tlb_hit
.valid | ~r0
.req
.virt_mode
)
740 with m
.If(r0
.req
.virt_mode
):
741 comb
+= ra
.eq(Cat(Const(0, ROW_OFF_BITS
),
742 r0
.req
.addr
[ROW_OFF_BITS
:TLB_LG_PGSZ
],
743 pte
[TLB_LG_PGSZ
:REAL_ADDR_BITS
]))
744 comb
+= perm_attr
.reference
.eq(pte
[8])
745 comb
+= perm_attr
.changed
.eq(pte
[7])
746 comb
+= perm_attr
.nocache
.eq(pte
[5])
747 comb
+= perm_attr
.priv
.eq(pte
[3])
748 comb
+= perm_attr
.rd_perm
.eq(pte
[2])
749 comb
+= perm_attr
.wr_perm
.eq(pte
[1])
751 comb
+= ra
.eq(Cat(Const(0, ROW_OFF_BITS
),
752 r0
.req
.addr
[ROW_OFF_BITS
:REAL_ADDR_BITS
]))
753 comb
+= perm_attr
.reference
.eq(1)
754 comb
+= perm_attr
.changed
.eq(1)
755 comb
+= perm_attr
.nocache
.eq(0)
756 comb
+= perm_attr
.priv
.eq(1)
757 comb
+= perm_attr
.rd_perm
.eq(1)
758 comb
+= perm_attr
.wr_perm
.eq(1)
761 m
.d
.sync
+= Display("DCACHE virt mode %d hit %d ra %x pte %x",
762 r0
.req
.virt_mode
, tlb_hit
.valid
, ra
, pte
)
763 m
.d
.sync
+= Display(" perm ref=%d", perm_attr
.reference
)
764 m
.d
.sync
+= Display(" perm chg=%d", perm_attr
.changed
)
765 m
.d
.sync
+= Display(" perm noc=%d", perm_attr
.nocache
)
766 m
.d
.sync
+= Display(" perm prv=%d", perm_attr
.priv
)
767 m
.d
.sync
+= Display(" perm rdp=%d", perm_attr
.rd_perm
)
768 m
.d
.sync
+= Display(" perm wrp=%d", perm_attr
.wr_perm
)
770 def tlb_update(self
, m
, r0_valid
, r0
, dtlb
, tlb_req_index
,
771 tlb_hit
, tlb_plru_victim
, tlb_way
):
779 comb
+= tlbie
.eq(r0_valid
& r0
.tlbie
)
780 comb
+= tlbwe
.eq(r0_valid
& r0
.tlbld
)
782 m
.submodules
.tlb_update
= d
= DTLBUpdate()
783 with m
.If(tlbie
& r0
.doall
):
784 # clear all valid bits at once
785 for i
in range(TLB_SET_SIZE
):
786 sync
+= dtlb
[i
].valid
.eq(0)
787 with m
.If(d
.updated
):
788 sync
+= dtlb
[tlb_req_index
].tag
.eq(d
.tb_out
)
789 sync
+= dtlb
[tlb_req_index
].pte
.eq(d
.pb_out
)
790 with m
.If(d
.v_updated
):
791 sync
+= dtlb
[tlb_req_index
].valid
.eq(d
.db_out
)
793 comb
+= d
.dv
.eq(dtlb
[tlb_req_index
].valid
)
795 comb
+= d
.tlbie
.eq(tlbie
)
796 comb
+= d
.tlbwe
.eq(tlbwe
)
797 comb
+= d
.doall
.eq(r0
.doall
)
798 comb
+= d
.tlb_hit
.eq(tlb_hit
)
799 comb
+= d
.tlb_tag_way
.eq(tlb_way
.tag
)
800 comb
+= d
.tlb_pte_way
.eq(tlb_way
.pte
)
801 comb
+= d
.tlb_req_index
.eq(tlb_req_index
)
803 with m
.If(tlb_hit
.valid
):
804 comb
+= d
.repl_way
.eq(tlb_hit
.way
)
806 comb
+= d
.repl_way
.eq(tlb_plru_victim
[tlb_req_index
])
807 comb
+= d
.eatag
.eq(r0
.req
.addr
[TLB_LG_PGSZ
+ TLB_SET_BITS
:64])
808 comb
+= d
.pte_data
.eq(r0
.req
.data
)
810 def maybe_plrus(self
, m
, r1
, plru_victim
):
816 if TLB_NUM_WAYS
== 0:
819 for i
in range(NUM_LINES
):
821 plru
= PLRU(WAY_BITS
)
822 setattr(m
.submodules
, "plru%d" % i
, plru
)
823 plru_acc_en
= Signal()
825 comb
+= plru_acc_en
.eq(r1
.cache_hit
& (r1
.hit_index
== i
))
826 comb
+= plru
.acc_en
.eq(plru_acc_en
)
827 comb
+= plru
.acc_i
.eq(r1
.hit_way
)
828 comb
+= plru_victim
[i
].eq(plru
.lru_o
)
830 def cache_tag_read(self
, m
, r0_stall
, req_index
, cache_tag_set
, cache_tags
):
831 """Cache tag RAM read port
835 m_in
, d_in
= self
.m_in
, self
.d_in
837 index
= Signal(INDEX_BITS
)
840 comb
+= index
.eq(req_index
)
841 with m
.Elif(m_in
.valid
):
842 comb
+= index
.eq(get_index(m_in
.addr
))
844 comb
+= index
.eq(get_index(d_in
.addr
))
845 sync
+= cache_tag_set
.eq(cache_tags
[index
].tag
)
847 def dcache_request(self
, m
, r0
, ra
, req_index
, req_row
, req_tag
,
848 r0_valid
, r1
, cache_tags
, replace_way
,
849 use_forward1_next
, use_forward2_next
,
850 req_hit_way
, plru_victim
, rc_ok
, perm_attr
,
851 valid_ra
, perm_ok
, access_ok
, req_op
, req_go
,
852 tlb_hit
, tlb_way
, cache_tag_set
,
853 cancel_store
, req_same_tag
, r0_stall
, early_req_row
):
854 """Cache request parsing and hit detection
858 m_in
, d_in
= self
.m_in
, self
.d_in
861 hit_way
= Signal(WAY_BITS
)
866 hit_set
= Array(Signal(name
="hit_set_%d" % i
) \
867 for i
in range(TLB_NUM_WAYS
))
868 cache_i_validdx
= Signal(NUM_WAYS
)
870 # Extract line, row and tag from request
871 comb
+= req_index
.eq(get_index(r0
.req
.addr
))
872 comb
+= req_row
.eq(get_row(r0
.req
.addr
))
873 comb
+= req_tag
.eq(get_tag(ra
))
875 if False: # display on comb is a bit... busy.
876 comb
+= Display("dcache_req addr:%x ra: %x idx: %x tag: %x row: %x",
877 r0
.req
.addr
, ra
, req_index
, req_tag
, req_row
)
879 comb
+= go
.eq(r0_valid
& ~
(r0
.tlbie | r0
.tlbld
) & ~r1
.ls_error
)
880 comb
+= cache_i_validdx
.eq(cache_tags
[req_index
].valid
)
882 m
.submodules
.dcache_pend
= dc
= DCachePendingHit(tlb_way
,
883 cache_i_validdx
, cache_tag_set
,
886 comb
+= dc
.tlb_hit
.eq(tlb_hit
)
887 comb
+= dc
.reload_tag
.eq(r1
.reload_tag
)
888 comb
+= dc
.virt_mode
.eq(r0
.req
.virt_mode
)
890 comb
+= dc
.req_index
.eq(req_index
)
892 comb
+= is_hit
.eq(dc
.is_hit
)
893 comb
+= hit_way
.eq(dc
.hit_way
)
894 comb
+= req_same_tag
.eq(dc
.rel_match
)
896 # See if the request matches the line currently being reloaded
897 with m
.If((r1
.state
== State
.RELOAD_WAIT_ACK
) &
898 (req_index
== r1
.store_index
) & req_same_tag
):
899 # For a store, consider this a hit even if the row isn't
900 # valid since it will be by the time we perform the store.
901 # For a load, check the appropriate row valid bit.
902 rrow
= Signal(ROW_LINE_BITS
)
903 comb
+= rrow
.eq(req_row
)
904 valid
= r1
.rows_valid
[rrow
]
905 comb
+= is_hit
.eq((~r0
.req
.load
) | valid
)
906 comb
+= hit_way
.eq(replace_way
)
908 # Whether to use forwarded data for a load or not
909 with m
.If((get_row(r1
.req
.real_addr
) == req_row
) &
910 (r1
.req
.hit_way
== hit_way
)):
911 # Only need to consider r1.write_bram here, since if we
912 # are writing refill data here, then we don't have a
913 # cache hit this cycle on the line being refilled.
914 # (There is the possibility that the load following the
915 # load miss that started the refill could be to the old
916 # contents of the victim line, since it is a couple of
917 # cycles after the refill starts before we see the updated
918 # cache tag. In that case we don't use the bypass.)
919 comb
+= use_forward1_next
.eq(r1
.write_bram
)
920 with m
.If((r1
.forward_row1
== req_row
) & (r1
.forward_way1
== hit_way
)):
921 comb
+= use_forward2_next
.eq(r1
.forward_valid1
)
923 # The way that matched on a hit
924 comb
+= req_hit_way
.eq(hit_way
)
926 # The way to replace on a miss
927 with m
.If(r1
.write_tag
):
928 comb
+= replace_way
.eq(plru_victim
[r1
.store_index
])
930 comb
+= replace_way
.eq(r1
.store_way
)
932 # work out whether we have permission for this access
933 # NB we don't yet implement AMR, thus no KUAP
934 comb
+= rc_ok
.eq(perm_attr
.reference
935 & (r0
.req
.load | perm_attr
.changed
))
936 comb
+= perm_ok
.eq((r0
.req
.priv_mode |
(~perm_attr
.priv
)) &
938 (r0
.req
.load
& perm_attr
.rd_perm
)))
939 comb
+= access_ok
.eq(valid_ra
& perm_ok
& rc_ok
)
941 # Combine the request and cache hit status to decide what
942 # operation needs to be done
943 comb
+= nc
.eq(r0
.req
.nc | perm_attr
.nocache
)
944 comb
+= op
.eq(Op
.OP_NONE
)
946 with m
.If(~access_ok
):
947 m
.d
.sync
+= Display("DCACHE access fail valid_ra=%d p=%d rc=%d",
948 valid_ra
, perm_ok
, rc_ok
)
949 comb
+= op
.eq(Op
.OP_BAD
)
950 with m
.Elif(cancel_store
):
951 m
.d
.sync
+= Display("DCACHE cancel store")
952 comb
+= op
.eq(Op
.OP_STCX_FAIL
)
954 m
.d
.sync
+= Display("DCACHE valid_ra=%d nc=%d ld=%d",
955 valid_ra
, nc
, r0
.req
.load
)
956 comb
+= opsel
.eq(Cat(is_hit
, nc
, r0
.req
.load
))
957 with m
.Switch(opsel
):
958 with m
.Case(0b101): comb
+= op
.eq(Op
.OP_LOAD_HIT
)
959 with m
.Case(0b100): comb
+= op
.eq(Op
.OP_LOAD_MISS
)
960 with m
.Case(0b110): comb
+= op
.eq(Op
.OP_LOAD_NC
)
961 with m
.Case(0b001): comb
+= op
.eq(Op
.OP_STORE_HIT
)
962 with m
.Case(0b000): comb
+= op
.eq(Op
.OP_STORE_MISS
)
963 with m
.Case(0b010): comb
+= op
.eq(Op
.OP_STORE_MISS
)
964 with m
.Case(0b011): comb
+= op
.eq(Op
.OP_BAD
)
965 with m
.Case(0b111): comb
+= op
.eq(Op
.OP_BAD
)
966 comb
+= req_op
.eq(op
)
967 comb
+= req_go
.eq(go
)
969 # Version of the row number that is valid one cycle earlier
970 # in the cases where we need to read the cache data BRAM.
971 # If we're stalling then we need to keep reading the last
973 with m
.If(~r0_stall
):
974 with m
.If(m_in
.valid
):
975 comb
+= early_req_row
.eq(get_row(m_in
.addr
))
977 comb
+= early_req_row
.eq(get_row(d_in
.addr
))
979 comb
+= early_req_row
.eq(req_row
)
981 def reservation_comb(self
, m
, cancel_store
, set_rsrv
, clear_rsrv
,
982 r0_valid
, r0
, reservation
):
983 """Handle load-with-reservation and store-conditional instructions
987 with m
.If(r0_valid
& r0
.req
.reserve
):
988 # XXX generate alignment interrupt if address
989 # is not aligned XXX or if r0.req.nc = '1'
990 with m
.If(r0
.req
.load
):
991 comb
+= set_rsrv
.eq(r0
.req
.atomic_last
) # load with reservation
993 comb
+= clear_rsrv
.eq(r0
.req
.atomic_last
) # store conditional
994 with m
.If((~reservation
.valid
) |
995 (r0
.req
.addr
[LINE_OFF_BITS
:64] != reservation
.addr
)):
996 comb
+= cancel_store
.eq(1)
998 def reservation_reg(self
, m
, r0_valid
, access_ok
, set_rsrv
, clear_rsrv
,
1003 with m
.If(r0_valid
& access_ok
):
1004 with m
.If(clear_rsrv
):
1005 sync
+= reservation
.valid
.eq(0)
1006 with m
.Elif(set_rsrv
):
1007 sync
+= reservation
.valid
.eq(1)
1008 sync
+= reservation
.addr
.eq(r0
.req
.addr
[LINE_OFF_BITS
:64])
1010 def writeback_control(self
, m
, r1
, cache_out_row
):
1011 """Return data for loads & completion control logic
1015 d_out
, m_out
= self
.d_out
, self
.m_out
1017 data_out
= Signal(64)
1018 data_fwd
= Signal(64)
1020 # Use the bypass if are reading the row that was
1021 # written 1 or 2 cycles ago, including for the
1022 # slow_valid = 1 case (i.e. completing a load
1023 # miss or a non-cacheable load).
1024 with m
.If(r1
.use_forward1
):
1025 comb
+= data_fwd
.eq(r1
.forward_data1
)
1027 comb
+= data_fwd
.eq(r1
.forward_data2
)
1029 comb
+= data_out
.eq(cache_out_row
)
1032 with m
.If(r1
.forward_sel
[i
]):
1033 dsel
= data_fwd
.word_select(i
, 8)
1034 comb
+= data_out
.word_select(i
, 8).eq(dsel
)
1036 # DCache output to LoadStore
1037 comb
+= d_out
.valid
.eq(r1
.ls_valid
)
1038 comb
+= d_out
.data
.eq(data_out
)
1039 comb
+= d_out
.store_done
.eq(~r1
.stcx_fail
)
1040 comb
+= d_out
.error
.eq(r1
.ls_error
)
1041 comb
+= d_out
.cache_paradox
.eq(r1
.cache_paradox
)
1044 comb
+= m_out
.done
.eq(r1
.mmu_done
)
1045 comb
+= m_out
.err
.eq(r1
.mmu_error
)
1046 comb
+= m_out
.data
.eq(data_out
)
1048 # We have a valid load or store hit or we just completed
1049 # a slow op such as a load miss, a NC load or a store
1051 # Note: the load hit is delayed by one cycle. However it
1052 # can still not collide with r.slow_valid (well unless I
1053 # miscalculated) because slow_valid can only be set on a
1054 # subsequent request and not on its first cycle (the state
1055 # machine must have advanced), which makes slow_valid
1056 # at least 2 cycles from the previous hit_load_valid.
1058 # Sanity: Only one of these must be set in any given cycle
1060 if False: # TODO: need Display to get this to work
1061 assert (r1
.slow_valid
& r1
.stcx_fail
) != 1, \
1062 "unexpected slow_valid collision with stcx_fail"
1064 assert ((r1
.slow_valid | r1
.stcx_fail
) | r1
.hit_load_valid
) != 1, \
1065 "unexpected hit_load_delayed collision with slow_valid"
1067 with m
.If(~r1
.mmu_req
):
1068 # Request came from loadstore1...
1069 # Load hit case is the standard path
1070 with m
.If(r1
.hit_load_valid
):
1071 sync
+= Display("completing load hit data=%x", data_out
)
1073 # error cases complete without stalling
1074 with m
.If(r1
.ls_error
):
1076 sync
+= Display("completing dcbz with error")
1078 sync
+= Display("completing ld/st with error")
1080 # Slow ops (load miss, NC, stores)
1081 with m
.If(r1
.slow_valid
):
1082 sync
+= Display("completing store or load miss adr=%x data=%x",
1083 r1
.req
.real_addr
, data_out
)
1086 # Request came from MMU
1087 with m
.If(r1
.hit_load_valid
):
1088 sync
+= Display("completing load hit to MMU, data=%x",
1090 # error cases complete without stalling
1091 with m
.If(r1
.mmu_error
):
1092 sync
+= Display("combpleting MMU ld with error")
1094 # Slow ops (i.e. load miss)
1095 with m
.If(r1
.slow_valid
):
1096 sync
+= Display("completing MMU load miss, adr=%x data=%x",
1097 r1
.req
.real_addr
, m_out
.data
)
1099 def rams(self
, m
, r1
, early_req_row
, cache_out_row
, replace_way
):
1101 Generate a cache RAM for each way. This handles the normal
1102 reads, writes from reloads and the special store-hit update
1105 Note: the BRAMs have an extra read buffer, meaning the output
1106 is pipelined an extra cycle. This differs from the
1107 icache. The writeback logic needs to take that into
1108 account by using 1-cycle delayed signals for load hits.
1113 for i
in range(NUM_WAYS
):
1114 do_read
= Signal(name
="do_rd%d" % i
)
1115 rd_addr
= Signal(ROW_BITS
, name
="rd_addr_%d" % i
)
1116 do_write
= Signal(name
="do_wr%d" % i
)
1117 wr_addr
= Signal(ROW_BITS
, name
="wr_addr_%d" % i
)
1118 wr_data
= Signal(WB_DATA_BITS
, name
="din_%d" % i
)
1119 wr_sel
= Signal(ROW_SIZE
)
1120 wr_sel_m
= Signal(ROW_SIZE
)
1121 _d_out
= Signal(WB_DATA_BITS
, name
="dout_%d" % i
) # cache_row_t
1123 way
= CacheRam(ROW_BITS
, WB_DATA_BITS
, ADD_BUF
=True, ram_num
=i
)
1124 setattr(m
.submodules
, "cacheram_%d" % i
, way
)
1126 comb
+= way
.rd_en
.eq(do_read
)
1127 comb
+= way
.rd_addr
.eq(rd_addr
)
1128 comb
+= _d_out
.eq(way
.rd_data_o
)
1129 comb
+= way
.wr_sel
.eq(wr_sel_m
)
1130 comb
+= way
.wr_addr
.eq(wr_addr
)
1131 comb
+= way
.wr_data
.eq(wr_data
)
1134 comb
+= do_read
.eq(1)
1135 comb
+= rd_addr
.eq(early_req_row
)
1136 with m
.If(r1
.hit_way
== i
):
1137 comb
+= cache_out_row
.eq(_d_out
)
1141 # Defaults to wishbone read responses (cache refill)
1143 # For timing, the mux on wr_data/sel/addr is not
1144 # dependent on anything other than the current state.
1146 with m
.If(r1
.write_bram
):
1147 # Write store data to BRAM. This happens one
1148 # cycle after the store is in r0.
1149 comb
+= wr_data
.eq(r1
.req
.data
)
1150 comb
+= wr_sel
.eq(r1
.req
.byte_sel
)
1151 comb
+= wr_addr
.eq(get_row(r1
.req
.real_addr
))
1153 with m
.If(i
== r1
.req
.hit_way
):
1154 comb
+= do_write
.eq(1)
1156 # Otherwise, we might be doing a reload or a DCBZ
1158 comb
+= wr_data
.eq(0)
1160 comb
+= wr_data
.eq(bus
.dat_r
)
1161 comb
+= wr_addr
.eq(r1
.store_row
)
1162 comb
+= wr_sel
.eq(~
0) # all 1s
1164 with m
.If((r1
.state
== State
.RELOAD_WAIT_ACK
)
1165 & bus
.ack
& (replace_way
== i
)):
1166 comb
+= do_write
.eq(1)
1168 # Mask write selects with do_write since BRAM
1169 # doesn't have a global write-enable
1170 with m
.If(do_write
):
1171 comb
+= wr_sel_m
.eq(wr_sel
)
1173 # Cache hit synchronous machine for the easy case.
1174 # This handles load hits.
1175 # It also handles error cases (TLB miss, cache paradox)
1176 def dcache_fast_hit(self
, m
, req_op
, r0_valid
, r0
, r1
,
1177 req_hit_way
, req_index
, req_tag
, access_ok
,
1178 tlb_hit
, tlb_req_index
):
1182 with m
.If(req_op
!= Op
.OP_NONE
):
1183 sync
+= Display("op:%d addr:%x nc: %d idx: %x tag: %x way: %x",
1184 req_op
, r0
.req
.addr
, r0
.req
.nc
,
1185 req_index
, req_tag
, req_hit_way
)
1187 with m
.If(r0_valid
):
1188 sync
+= r1
.mmu_req
.eq(r0
.mmu_req
)
1190 # Fast path for load/store hits.
1191 # Set signals for the writeback controls.
1192 sync
+= r1
.hit_way
.eq(req_hit_way
)
1193 sync
+= r1
.hit_index
.eq(req_index
)
1195 sync
+= r1
.hit_load_valid
.eq(req_op
== Op
.OP_LOAD_HIT
)
1196 sync
+= r1
.cache_hit
.eq((req_op
== Op
.OP_LOAD_HIT
) |
1197 (req_op
== Op
.OP_STORE_HIT
))
1199 with m
.If(req_op
== Op
.OP_BAD
):
1200 sync
+= Display("Signalling ld/st error "
1201 "ls_error=%i mmu_error=%i cache_paradox=%i",
1202 ~r0
.mmu_req
,r0
.mmu_req
,access_ok
)
1203 sync
+= r1
.ls_error
.eq(~r0
.mmu_req
)
1204 sync
+= r1
.mmu_error
.eq(r0
.mmu_req
)
1205 sync
+= r1
.cache_paradox
.eq(access_ok
)
1207 sync
+= r1
.ls_error
.eq(0)
1208 sync
+= r1
.mmu_error
.eq(0)
1209 sync
+= r1
.cache_paradox
.eq(0)
1211 sync
+= r1
.stcx_fail
.eq(req_op
== Op
.OP_STCX_FAIL
)
1213 # Record TLB hit information for updating TLB PLRU
1214 sync
+= r1
.tlb_hit
.eq(tlb_hit
)
1215 sync
+= r1
.tlb_hit_index
.eq(tlb_req_index
)
1217 # Memory accesses are handled by this state machine:
1219 # * Cache load miss/reload (in conjunction with "rams")
1220 # * Load hits for non-cachable forms
1221 # * Stores (the collision case is handled in "rams")
1223 # All wishbone requests generation is done here.
1224 # This machine operates at stage 1.
1225 def dcache_slow(self
, m
, r1
, use_forward1_next
, use_forward2_next
,
1227 req_hit_way
, req_same_tag
,
1228 r0_valid
, req_op
, cache_tags
, req_go
, ra
):
1235 req
= MemAccessRequest("mreq_ds")
1237 req_row
= Signal(ROW_BITS
)
1238 req_idx
= Signal(INDEX_BITS
)
1239 req_tag
= Signal(TAG_BITS
)
1240 comb
+= req_idx
.eq(get_index(req
.real_addr
))
1241 comb
+= req_row
.eq(get_row(req
.real_addr
))
1242 comb
+= req_tag
.eq(get_tag(req
.real_addr
))
1244 sync
+= r1
.use_forward1
.eq(use_forward1_next
)
1245 sync
+= r1
.forward_sel
.eq(0)
1247 with m
.If(use_forward1_next
):
1248 sync
+= r1
.forward_sel
.eq(r1
.req
.byte_sel
)
1249 with m
.Elif(use_forward2_next
):
1250 sync
+= r1
.forward_sel
.eq(r1
.forward_sel1
)
1252 sync
+= r1
.forward_data2
.eq(r1
.forward_data1
)
1253 with m
.If(r1
.write_bram
):
1254 sync
+= r1
.forward_data1
.eq(r1
.req
.data
)
1255 sync
+= r1
.forward_sel1
.eq(r1
.req
.byte_sel
)
1256 sync
+= r1
.forward_way1
.eq(r1
.req
.hit_way
)
1257 sync
+= r1
.forward_row1
.eq(get_row(r1
.req
.real_addr
))
1258 sync
+= r1
.forward_valid1
.eq(1)
1261 sync
+= r1
.forward_data1
.eq(0)
1263 sync
+= r1
.forward_data1
.eq(bus
.dat_r
)
1264 sync
+= r1
.forward_sel1
.eq(~
0) # all 1s
1265 sync
+= r1
.forward_way1
.eq(replace_way
)
1266 sync
+= r1
.forward_row1
.eq(r1
.store_row
)
1267 sync
+= r1
.forward_valid1
.eq(0)
1269 # One cycle pulses reset
1270 sync
+= r1
.slow_valid
.eq(0)
1271 sync
+= r1
.write_bram
.eq(0)
1272 sync
+= r1
.inc_acks
.eq(0)
1273 sync
+= r1
.dec_acks
.eq(0)
1275 sync
+= r1
.ls_valid
.eq(0)
1276 # complete tlbies and TLB loads in the third cycle
1277 sync
+= r1
.mmu_done
.eq(r0_valid
& (r0
.tlbie | r0
.tlbld
))
1279 with m
.If((req_op
== Op
.OP_LOAD_HIT
) |
(req_op
== Op
.OP_STCX_FAIL
)):
1280 with m
.If(~r0
.mmu_req
):
1281 sync
+= r1
.ls_valid
.eq(1)
1283 sync
+= r1
.mmu_done
.eq(1)
1285 with m
.If(r1
.write_tag
):
1286 # Store new tag in selected way
1287 for i
in range(NUM_WAYS
):
1288 with m
.If(i
== replace_way
):
1289 ct
= Signal(TAG_RAM_WIDTH
)
1290 comb
+= ct
.eq(cache_tags
[r1
.store_index
].tag
)
1291 comb
+= ct
.word_select(i
, TAG_WIDTH
).eq(r1
.reload_tag
)
1292 sync
+= cache_tags
[r1
.store_index
].tag
.eq(ct
)
1293 sync
+= r1
.store_way
.eq(replace_way
)
1294 sync
+= r1
.write_tag
.eq(0)
1296 # Take request from r1.req if there is one there,
1297 # else from req_op, ra, etc.
1299 comb
+= req
.eq(r1
.req
)
1301 comb
+= req
.op
.eq(req_op
)
1302 comb
+= req
.valid
.eq(req_go
)
1303 comb
+= req
.mmu_req
.eq(r0
.mmu_req
)
1304 comb
+= req
.dcbz
.eq(r0
.req
.dcbz
)
1305 comb
+= req
.real_addr
.eq(ra
)
1307 with m
.If(r0
.req
.dcbz
):
1308 # force data to 0 for dcbz
1309 comb
+= req
.data
.eq(0)
1310 with m
.Elif(r0
.d_valid
):
1311 comb
+= req
.data
.eq(r0
.req
.data
)
1313 comb
+= req
.data
.eq(d_in
.data
)
1315 # Select all bytes for dcbz
1316 # and for cacheable loads
1317 with m
.If(r0
.req
.dcbz |
(r0
.req
.load
& ~r0
.req
.nc
)):
1318 comb
+= req
.byte_sel
.eq(~
0) # all 1s
1320 comb
+= req
.byte_sel
.eq(r0
.req
.byte_sel
)
1321 comb
+= req
.hit_way
.eq(req_hit_way
)
1322 comb
+= req
.same_tag
.eq(req_same_tag
)
1324 # Store the incoming request from r0,
1325 # if it is a slow request
1326 # Note that r1.full = 1 implies req_op = OP_NONE
1327 with m
.If((req_op
== Op
.OP_LOAD_MISS
)
1328 |
(req_op
== Op
.OP_LOAD_NC
)
1329 |
(req_op
== Op
.OP_STORE_MISS
)
1330 |
(req_op
== Op
.OP_STORE_HIT
)):
1331 sync
+= r1
.req
.eq(req
)
1332 sync
+= r1
.full
.eq(1)
1334 # Main state machine
1335 with m
.Switch(r1
.state
):
1337 with m
.Case(State
.IDLE
):
1338 sync
+= r1
.wb
.adr
.eq(req
.real_addr
[ROW_LINE_BITS
:])
1339 sync
+= r1
.wb
.sel
.eq(req
.byte_sel
)
1340 sync
+= r1
.wb
.dat
.eq(req
.data
)
1341 sync
+= r1
.dcbz
.eq(req
.dcbz
)
1343 # Keep track of our index and way
1344 # for subsequent stores.
1345 sync
+= r1
.store_index
.eq(req_idx
)
1346 sync
+= r1
.store_row
.eq(req_row
)
1347 sync
+= r1
.end_row_ix
.eq(get_row_of_line(req_row
)-1)
1348 sync
+= r1
.reload_tag
.eq(req_tag
)
1349 sync
+= r1
.req
.same_tag
.eq(1)
1351 with m
.If(req
.op
== Op
.OP_STORE_HIT
):
1352 sync
+= r1
.store_way
.eq(req
.hit_way
)
1354 # Reset per-row valid bits,
1355 # ready for handling OP_LOAD_MISS
1356 for i
in range(ROW_PER_LINE
):
1357 sync
+= r1
.rows_valid
[i
].eq(0)
1359 with m
.If(req_op
!= Op
.OP_NONE
):
1360 sync
+= Display("cache op %d", req
.op
)
1362 with m
.Switch(req
.op
):
1363 with m
.Case(Op
.OP_LOAD_HIT
):
1364 # stay in IDLE state
1367 with m
.Case(Op
.OP_LOAD_MISS
):
1368 sync
+= Display("cache miss real addr: %x " \
1370 req
.real_addr
, req_row
, req_tag
)
1372 # Start the wishbone cycle
1373 sync
+= r1
.wb
.we
.eq(0)
1374 sync
+= r1
.wb
.cyc
.eq(1)
1375 sync
+= r1
.wb
.stb
.eq(1)
1377 # Track that we had one request sent
1378 sync
+= r1
.state
.eq(State
.RELOAD_WAIT_ACK
)
1379 sync
+= r1
.write_tag
.eq(1)
1381 with m
.Case(Op
.OP_LOAD_NC
):
1382 sync
+= r1
.wb
.cyc
.eq(1)
1383 sync
+= r1
.wb
.stb
.eq(1)
1384 sync
+= r1
.wb
.we
.eq(0)
1385 sync
+= r1
.state
.eq(State
.NC_LOAD_WAIT_ACK
)
1387 with m
.Case(Op
.OP_STORE_HIT
, Op
.OP_STORE_MISS
):
1388 with m
.If(~req
.dcbz
):
1389 sync
+= r1
.state
.eq(State
.STORE_WAIT_ACK
)
1390 sync
+= r1
.acks_pending
.eq(1)
1391 sync
+= r1
.full
.eq(0)
1392 sync
+= r1
.slow_valid
.eq(1)
1394 with m
.If(~req
.mmu_req
):
1395 sync
+= r1
.ls_valid
.eq(1)
1397 sync
+= r1
.mmu_done
.eq(1)
1399 with m
.If(req
.op
== Op
.OP_STORE_HIT
):
1400 sync
+= r1
.write_bram
.eq(1)
1402 # dcbz is handled much like a load miss except
1403 # that we are writing to memory instead of reading
1404 sync
+= r1
.state
.eq(State
.RELOAD_WAIT_ACK
)
1406 with m
.If(req
.op
== Op
.OP_STORE_MISS
):
1407 sync
+= r1
.write_tag
.eq(1)
1409 sync
+= r1
.wb
.we
.eq(1)
1410 sync
+= r1
.wb
.cyc
.eq(1)
1411 sync
+= r1
.wb
.stb
.eq(1)
1413 # OP_NONE and OP_BAD do nothing
1414 # OP_BAD & OP_STCX_FAIL were
1415 # handled above already
1416 with m
.Case(Op
.OP_NONE
):
1418 with m
.Case(Op
.OP_BAD
):
1420 with m
.Case(Op
.OP_STCX_FAIL
):
1423 with m
.Case(State
.RELOAD_WAIT_ACK
):
1424 ld_stbs_done
= Signal()
1425 # Requests are all sent if stb is 0
1426 comb
+= ld_stbs_done
.eq(~r1
.wb
.stb
)
1428 # If we are still sending requests, was one accepted?
1429 with m
.If((~bus
.stall
) & r1
.wb
.stb
):
1430 # That was the last word? We are done sending.
1431 # Clear stb and set ld_stbs_done so we can handle an
1432 # eventual last ack on the same cycle.
1433 # sigh - reconstruct wb adr with 3 extra 0s at front
1434 wb_adr
= Cat(Const(0, ROW_OFF_BITS
), r1
.wb
.adr
)
1435 with m
.If(is_last_row_addr(wb_adr
, r1
.end_row_ix
)):
1436 sync
+= r1
.wb
.stb
.eq(0)
1437 comb
+= ld_stbs_done
.eq(1)
1439 # Calculate the next row address in the current cache line
1440 row
= Signal(LINE_OFF_BITS
-ROW_OFF_BITS
)
1441 comb
+= row
.eq(r1
.wb
.adr
)
1442 sync
+= r1
.wb
.adr
[:LINE_OFF_BITS
-ROW_OFF_BITS
].eq(row
+1)
1444 # Incoming acks processing
1445 sync
+= r1
.forward_valid1
.eq(bus
.ack
)
1447 srow
= Signal(ROW_LINE_BITS
)
1448 comb
+= srow
.eq(r1
.store_row
)
1449 sync
+= r1
.rows_valid
[srow
].eq(1)
1451 # If this is the data we were looking for,
1452 # we can complete the request next cycle.
1453 # Compare the whole address in case the
1454 # request in r1.req is not the one that
1455 # started this refill.
1456 with m
.If(req
.valid
& r1
.req
.same_tag
&
1457 ((r1
.dcbz
& r1
.req
.dcbz
) |
1458 (~r1
.dcbz
& (r1
.req
.op
== Op
.OP_LOAD_MISS
))) &
1459 (r1
.store_row
== get_row(req
.real_addr
))):
1460 sync
+= r1
.full
.eq(0)
1461 sync
+= r1
.slow_valid
.eq(1)
1462 with m
.If(~r1
.mmu_req
):
1463 sync
+= r1
.ls_valid
.eq(1)
1465 sync
+= r1
.mmu_done
.eq(1)
1466 sync
+= r1
.forward_sel
.eq(~
0) # all 1s
1467 sync
+= r1
.use_forward1
.eq(1)
1469 # Check for completion
1470 with m
.If(ld_stbs_done
& is_last_row(r1
.store_row
,
1472 # Complete wishbone cycle
1473 sync
+= r1
.wb
.cyc
.eq(0)
1475 # Cache line is now valid
1476 cv
= Signal(INDEX_BITS
)
1477 comb
+= cv
.eq(cache_tags
[r1
.store_index
].valid
)
1478 comb
+= cv
.bit_select(r1
.store_way
, 1).eq(1)
1479 sync
+= cache_tags
[r1
.store_index
].valid
.eq(cv
)
1481 sync
+= r1
.state
.eq(State
.IDLE
)
1482 sync
+= Display("cache valid set %x "
1484 cv
, r1
.store_index
, r1
.store_way
)
1486 # Increment store row counter
1487 sync
+= r1
.store_row
.eq(next_row(r1
.store_row
))
1489 with m
.Case(State
.STORE_WAIT_ACK
):
1490 st_stbs_done
= Signal()
1492 adjust_acks
= Signal(3)
1494 comb
+= st_stbs_done
.eq(~r1
.wb
.stb
)
1495 comb
+= acks
.eq(r1
.acks_pending
)
1497 with m
.If(r1
.inc_acks
!= r1
.dec_acks
):
1498 with m
.If(r1
.inc_acks
):
1499 comb
+= adjust_acks
.eq(acks
+ 1)
1501 comb
+= adjust_acks
.eq(acks
- 1)
1503 comb
+= adjust_acks
.eq(acks
)
1505 sync
+= r1
.acks_pending
.eq(adjust_acks
)
1507 # Clear stb when slave accepted request
1508 with m
.If(~bus
.stall
):
1509 # See if there is another store waiting
1510 # to be done which is in the same real page.
1511 with m
.If(req
.valid
):
1512 _ra
= req
.real_addr
[ROW_LINE_BITS
:SET_SIZE_BITS
]
1513 sync
+= r1
.wb
.adr
[0:SET_SIZE_BITS
].eq(_ra
)
1514 sync
+= r1
.wb
.dat
.eq(req
.data
)
1515 sync
+= r1
.wb
.sel
.eq(req
.byte_sel
)
1517 with m
.If((adjust_acks
< 7) & req
.same_tag
&
1518 ((req
.op
== Op
.OP_STORE_MISS
)
1519 |
(req
.op
== Op
.OP_STORE_HIT
))):
1520 sync
+= r1
.wb
.stb
.eq(1)
1521 comb
+= st_stbs_done
.eq(0)
1523 with m
.If(req
.op
== Op
.OP_STORE_HIT
):
1524 sync
+= r1
.write_bram
.eq(1)
1525 sync
+= r1
.full
.eq(0)
1526 sync
+= r1
.slow_valid
.eq(1)
1528 # Store requests never come from the MMU
1529 sync
+= r1
.ls_valid
.eq(1)
1530 comb
+= st_stbs_done
.eq(0)
1531 sync
+= r1
.inc_acks
.eq(1)
1533 sync
+= r1
.wb
.stb
.eq(0)
1534 comb
+= st_stbs_done
.eq(1)
1536 # Got ack ? See if complete.
1538 with m
.If(st_stbs_done
& (adjust_acks
== 1)):
1539 sync
+= r1
.state
.eq(State
.IDLE
)
1540 sync
+= r1
.wb
.cyc
.eq(0)
1541 sync
+= r1
.wb
.stb
.eq(0)
1542 sync
+= r1
.dec_acks
.eq(1)
1544 with m
.Case(State
.NC_LOAD_WAIT_ACK
):
1545 # Clear stb when slave accepted request
1546 with m
.If(~bus
.stall
):
1547 sync
+= r1
.wb
.stb
.eq(0)
1549 # Got ack ? complete.
1551 sync
+= r1
.state
.eq(State
.IDLE
)
1552 sync
+= r1
.full
.eq(0)
1553 sync
+= r1
.slow_valid
.eq(1)
1555 with m
.If(~r1
.mmu_req
):
1556 sync
+= r1
.ls_valid
.eq(1)
1558 sync
+= r1
.mmu_done
.eq(1)
1560 sync
+= r1
.forward_sel
.eq(~
0) # all 1s
1561 sync
+= r1
.use_forward1
.eq(1)
1562 sync
+= r1
.wb
.cyc
.eq(0)
1563 sync
+= r1
.wb
.stb
.eq(0)
1565 def dcache_log(self
, m
, r1
, valid_ra
, tlb_hit
, stall_out
):
1568 d_out
, bus
, log_out
= self
.d_out
, self
.bus
, self
.log_out
1570 sync
+= log_out
.eq(Cat(r1
.state
[:3], valid_ra
, tlb_hit
.way
[:3],
1571 stall_out
, req_op
[:3], d_out
.valid
, d_out
.error
,
1572 r1
.wb
.cyc
, r1
.wb
.stb
, bus
.ack
, bus
.stall
,
1575 def elaborate(self
, platform
):
1581 # Storage. Hopefully "cache_rows" is a BRAM, the rest is LUTs
1582 cache_tags
= CacheTagArray()
1583 cache_tag_set
= Signal(TAG_RAM_WIDTH
)
1585 # TODO attribute ram_style : string;
1586 # TODO attribute ram_style of cache_tags : signal is "distributed";
1588 """note: these are passed to nmigen.hdl.Memory as "attributes".
1589 don't know how, just that they are.
1592 # TODO attribute ram_style of
1593 # dtlb_tags : signal is "distributed";
1594 # TODO attribute ram_style of
1595 # dtlb_ptes : signal is "distributed";
1597 r0
= RegStage0("r0")
1600 r1
= RegStage1("r1")
1602 reservation
= Reservation()
1604 # Async signals on incoming request
1605 req_index
= Signal(INDEX_BITS
)
1606 req_row
= Signal(ROW_BITS
)
1607 req_hit_way
= Signal(WAY_BITS
)
1608 req_tag
= Signal(TAG_BITS
)
1610 req_data
= Signal(64)
1611 req_same_tag
= Signal()
1614 early_req_row
= Signal(ROW_BITS
)
1616 cancel_store
= Signal()
1618 clear_rsrv
= Signal()
1623 use_forward1_next
= Signal()
1624 use_forward2_next
= Signal()
1626 cache_out_row
= Signal(WB_DATA_BITS
)
1628 plru_victim
= PLRUOut()
1629 replace_way
= Signal(WAY_BITS
)
1631 # Wishbone read/write/cache write formatting signals
1635 tlb_way
= TLBRecord("tlb_way")
1636 tlb_req_index
= Signal(TLB_SET_BITS
)
1637 tlb_hit
= TLBHit("tlb_hit")
1638 pte
= Signal(TLB_PTE_BITS
)
1639 ra
= Signal(REAL_ADDR_BITS
)
1641 perm_attr
= PermAttr("dc_perms")
1644 access_ok
= Signal()
1646 tlb_plru_victim
= TLBPLRUOut()
1648 # we don't yet handle collisions between loadstore1 requests
1650 comb
+= self
.m_out
.stall
.eq(0)
1652 # Hold off the request in r0 when r1 has an uncompleted request
1653 comb
+= r0_stall
.eq(r0_full
& (r1
.full | d_in
.hold
))
1654 comb
+= r0_valid
.eq(r0_full
& ~r1
.full
& ~d_in
.hold
)
1655 comb
+= self
.stall_out
.eq(r0_stall
)
1657 # deal with litex not doing wishbone pipeline mode
1658 # XXX in wrong way. FIFOs are needed in the SRAM test
1659 # so that stb/ack match up. same thing done in icache.py
1660 comb
+= self
.bus
.stall
.eq(self
.bus
.cyc
& ~self
.bus
.ack
)
1662 # Wire up wishbone request latch out of stage 1
1663 comb
+= self
.bus
.we
.eq(r1
.wb
.we
)
1664 comb
+= self
.bus
.adr
.eq(r1
.wb
.adr
)
1665 comb
+= self
.bus
.sel
.eq(r1
.wb
.sel
)
1666 comb
+= self
.bus
.stb
.eq(r1
.wb
.stb
)
1667 comb
+= self
.bus
.dat_w
.eq(r1
.wb
.dat
)
1668 comb
+= self
.bus
.cyc
.eq(r1
.wb
.cyc
)
1670 # call sub-functions putting everything together, using shared
1671 # signals established above
1672 self
.stage_0(m
, r0
, r1
, r0_full
)
1673 self
.tlb_read(m
, r0_stall
, tlb_way
, dtlb
)
1674 self
.tlb_search(m
, tlb_req_index
, r0
, r0_valid
,
1676 pte
, tlb_hit
, valid_ra
, perm_attr
, ra
)
1677 self
.tlb_update(m
, r0_valid
, r0
, dtlb
, tlb_req_index
,
1678 tlb_hit
, tlb_plru_victim
,
1680 self
.maybe_plrus(m
, r1
, plru_victim
)
1681 self
.maybe_tlb_plrus(m
, r1
, tlb_plru_victim
)
1682 self
.cache_tag_read(m
, r0_stall
, req_index
, cache_tag_set
, cache_tags
)
1683 self
.dcache_request(m
, r0
, ra
, req_index
, req_row
, req_tag
,
1684 r0_valid
, r1
, cache_tags
, replace_way
,
1685 use_forward1_next
, use_forward2_next
,
1686 req_hit_way
, plru_victim
, rc_ok
, perm_attr
,
1687 valid_ra
, perm_ok
, access_ok
, req_op
, req_go
,
1688 tlb_hit
, tlb_way
, cache_tag_set
,
1689 cancel_store
, req_same_tag
, r0_stall
, early_req_row
)
1690 self
.reservation_comb(m
, cancel_store
, set_rsrv
, clear_rsrv
,
1691 r0_valid
, r0
, reservation
)
1692 self
.reservation_reg(m
, r0_valid
, access_ok
, set_rsrv
, clear_rsrv
,
1694 self
.writeback_control(m
, r1
, cache_out_row
)
1695 self
.rams(m
, r1
, early_req_row
, cache_out_row
, replace_way
)
1696 self
.dcache_fast_hit(m
, req_op
, r0_valid
, r0
, r1
,
1697 req_hit_way
, req_index
, req_tag
, access_ok
,
1698 tlb_hit
, tlb_req_index
)
1699 self
.dcache_slow(m
, r1
, use_forward1_next
, use_forward2_next
,
1701 req_hit_way
, req_same_tag
,
1702 r0_valid
, req_op
, cache_tags
, req_go
, ra
)
1703 #self.dcache_log(m, r1, valid_ra, tlb_hit, stall_out)
1708 if __name__
== '__main__':
1710 vl
= rtlil
.convert(dut
, ports
=[])
1711 with
open("test_dcache.il", "w") as f
: