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
30 from nmigen
.lib
.coding
import Decoder
32 from copy
import deepcopy
33 from random
import randint
, seed
35 from nmigen_soc
.wishbone
.bus
import Interface
37 from nmigen
.cli
import main
38 from nmutil
.iocontrol
import RecordObject
39 from nmigen
.utils
import log2_int
40 from soc
.experiment
.mem_types
import (LoadStore1ToDCacheType
,
41 DCacheToLoadStore1Type
,
45 from soc
.experiment
.wb_types
import (WB_ADDR_BITS
, WB_DATA_BITS
, WB_SEL_BITS
,
46 WBAddrType
, WBDataType
, WBSelType
,
47 WBMasterOut
, WBSlaveOut
,
48 WBMasterOutVector
, WBSlaveOutVector
,
49 WBIOMasterOut
, WBIOSlaveOut
)
51 from soc
.experiment
.cache_ram
import CacheRam
52 #from soc.experiment.plru import PLRU
53 from nmutil
.plru
import PLRU
, PLRUs
56 from soc
.bus
.sram
import SRAM
57 from nmigen
import Memory
58 from nmigen
.cli
import rtlil
60 # NOTE: to use cxxsim, export NMIGEN_SIM_MODE=cxxsim from the shell
61 # Also, check out the cxxsim nmigen branch, and latest yosys from git
62 from nmutil
.sim_tmp_alternative
import Simulator
64 from nmutil
.util
import wrap
67 # TODO: make these parameters of DCache at some point
68 LINE_SIZE
= 64 # Line size in bytes
69 NUM_LINES
= 16 # Number of lines in a set
70 NUM_WAYS
= 4 # Number of ways
71 TLB_SET_SIZE
= 64 # L1 DTLB entries per set
72 TLB_NUM_WAYS
= 2 # L1 DTLB number of sets
73 TLB_LG_PGSZ
= 12 # L1 DTLB log_2(page_size)
74 LOG_LENGTH
= 0 # Non-zero to enable log data collection
76 # BRAM organisation: We never access more than
77 # -- WB_DATA_BITS at a time so to save
78 # -- resources we make the array only that wide, and
79 # -- use consecutive indices to make a cache "line"
81 # -- ROW_SIZE is the width in bytes of the BRAM
82 # -- (based on WB, so 64-bits)
83 ROW_SIZE
= WB_DATA_BITS
// 8;
85 # ROW_PER_LINE is the number of row (wishbone
86 # transactions) in a line
87 ROW_PER_LINE
= LINE_SIZE
// ROW_SIZE
89 # BRAM_ROWS is the number of rows in BRAM needed
90 # to represent the full dcache
91 BRAM_ROWS
= NUM_LINES
* ROW_PER_LINE
93 print ("ROW_SIZE", ROW_SIZE
)
94 print ("ROW_PER_LINE", ROW_PER_LINE
)
95 print ("BRAM_ROWS", BRAM_ROWS
)
96 print ("NUM_WAYS", NUM_WAYS
)
98 # Bit fields counts in the address
100 # REAL_ADDR_BITS is the number of real address
104 # ROW_BITS is the number of bits to select a row
105 ROW_BITS
= log2_int(BRAM_ROWS
)
107 # ROW_LINE_BITS is the number of bits to select
108 # a row within a line
109 ROW_LINE_BITS
= log2_int(ROW_PER_LINE
)
111 # LINE_OFF_BITS is the number of bits for
112 # the offset in a cache line
113 LINE_OFF_BITS
= log2_int(LINE_SIZE
)
115 # ROW_OFF_BITS is the number of bits for
116 # the offset in a row
117 ROW_OFF_BITS
= log2_int(ROW_SIZE
)
119 # INDEX_BITS is the number if bits to
120 # select a cache line
121 INDEX_BITS
= log2_int(NUM_LINES
)
123 # SET_SIZE_BITS is the log base 2 of the set size
124 SET_SIZE_BITS
= LINE_OFF_BITS
+ INDEX_BITS
126 # TAG_BITS is the number of bits of
127 # the tag part of the address
128 TAG_BITS
= REAL_ADDR_BITS
- SET_SIZE_BITS
130 # TAG_WIDTH is the width in bits of each way of the tag RAM
131 TAG_WIDTH
= TAG_BITS
+ 7 - ((TAG_BITS
+ 7) % 8)
133 # WAY_BITS is the number of bits to select a way
134 WAY_BITS
= log2_int(NUM_WAYS
)
136 # Example of layout for 32 lines of 64 bytes:
138 .. tag |index| line |
140 .. | |---| | ROW_LINE_BITS (3)
141 .. | |--- - --| LINE_OFF_BITS (6)
142 .. | |- --| ROW_OFF_BITS (3)
143 .. |----- ---| | ROW_BITS (8)
144 .. |-----| | INDEX_BITS (5)
145 .. --------| | TAG_BITS (45)
148 print ("Dcache TAG %d IDX %d ROW_BITS %d ROFF %d LOFF %d RLB %d" % \
149 (TAG_BITS
, INDEX_BITS
, ROW_BITS
,
150 ROW_OFF_BITS
, LINE_OFF_BITS
, ROW_LINE_BITS
))
151 print ("index @: %d-%d" % (LINE_OFF_BITS
, SET_SIZE_BITS
))
152 print ("row @: %d-%d" % (LINE_OFF_BITS
, ROW_OFF_BITS
))
153 print ("tag @: %d-%d width %d" % (SET_SIZE_BITS
, REAL_ADDR_BITS
, TAG_WIDTH
))
155 TAG_RAM_WIDTH
= TAG_WIDTH
* NUM_WAYS
157 print ("TAG_RAM_WIDTH", TAG_RAM_WIDTH
)
160 tag_layout
= [('valid', 1),
161 ('tag', TAG_RAM_WIDTH
),
163 return Array(Record(tag_layout
, name
="tag%d" % x
) for x
in range(NUM_LINES
))
165 def RowPerLineValidArray():
166 return Array(Signal(name
="rows_valid%d" % x
) \
167 for x
in range(ROW_PER_LINE
))
170 TLB_SET_BITS
= log2_int(TLB_SET_SIZE
)
171 TLB_WAY_BITS
= log2_int(TLB_NUM_WAYS
)
172 TLB_EA_TAG_BITS
= 64 - (TLB_LG_PGSZ
+ TLB_SET_BITS
)
173 TLB_TAG_WAY_BITS
= TLB_NUM_WAYS
* TLB_EA_TAG_BITS
175 TLB_PTE_WAY_BITS
= TLB_NUM_WAYS
* TLB_PTE_BITS
;
178 return (1<<log2_int(x
, False)) == x
180 assert (LINE_SIZE
% ROW_SIZE
) == 0, "LINE_SIZE not multiple of ROW_SIZE"
181 assert ispow2(LINE_SIZE
), "LINE_SIZE not power of 2"
182 assert ispow2(NUM_LINES
), "NUM_LINES not power of 2"
183 assert ispow2(ROW_PER_LINE
), "ROW_PER_LINE not power of 2"
184 assert ROW_BITS
== (INDEX_BITS
+ ROW_LINE_BITS
), "geometry bits don't add up"
185 assert (LINE_OFF_BITS
== ROW_OFF_BITS
+ ROW_LINE_BITS
), \
186 "geometry bits don't add up"
187 assert REAL_ADDR_BITS
== (TAG_BITS
+ INDEX_BITS
+ LINE_OFF_BITS
), \
188 "geometry bits don't add up"
189 assert REAL_ADDR_BITS
== (TAG_BITS
+ ROW_BITS
+ ROW_OFF_BITS
), \
190 "geometry bits don't add up"
191 assert 64 == WB_DATA_BITS
, "Can't yet handle wb width that isn't 64-bits"
192 assert SET_SIZE_BITS
<= TLB_LG_PGSZ
, "Set indexed by virtual address"
195 return Record([('valid', 1),
196 ('way', TLB_WAY_BITS
)], name
=name
)
199 return Array(Signal(TLB_EA_TAG_BITS
, name
="tlbtagea%d" % x
) \
200 for x
in range (TLB_NUM_WAYS
))
203 tlb_layout
= [('valid', TLB_NUM_WAYS
),
204 ('tag', TLB_TAG_WAY_BITS
),
205 ('pte', TLB_PTE_WAY_BITS
)
207 return Record(tlb_layout
, name
=name
)
210 return Array(TLBRecord(name
="tlb%d" % x
) for x
in range(TLB_SET_SIZE
))
213 return Array(Signal(WAY_BITS
, name
="hitway_%d" % x
) \
214 for x
in range(TLB_NUM_WAYS
))
216 # Cache RAM interface
218 return Array(Signal(WB_DATA_BITS
, name
="cache_out%d" % x
) \
219 for x
in range(NUM_WAYS
))
221 # PLRU output interface
223 return Array(Signal(WAY_BITS
, name
="plru_out%d" % x
) \
224 for x
in range(NUM_LINES
))
226 # TLB PLRU output interface
228 return Array(Signal(TLB_WAY_BITS
, name
="tlbplru_out%d" % x
) \
229 for x
in range(TLB_SET_SIZE
))
231 # Helper functions to decode incoming requests
233 # Return the cache line index (tag index) for an address
235 return addr
[LINE_OFF_BITS
:SET_SIZE_BITS
]
237 # Return the cache row index (data memory) for an address
239 return addr
[ROW_OFF_BITS
:SET_SIZE_BITS
]
241 # Return the index of a row within a line
242 def get_row_of_line(row
):
243 return row
[:ROW_BITS
][:ROW_LINE_BITS
]
245 # Returns whether this is the last row of a line
246 def is_last_row_addr(addr
, last
):
247 return addr
[ROW_OFF_BITS
:LINE_OFF_BITS
] == last
249 # Returns whether this is the last row of a line
250 def is_last_row(row
, last
):
251 return get_row_of_line(row
) == last
253 # Return the next row in the current cache line. We use a
254 # dedicated function in order to limit the size of the
255 # generated adder to be only the bits within a cache line
256 # (3 bits with default settings)
258 row_v
= row
[0:ROW_LINE_BITS
] + 1
259 return Cat(row_v
[:ROW_LINE_BITS
], row
[ROW_LINE_BITS
:])
261 # Get the tag value from the address
263 return addr
[SET_SIZE_BITS
:REAL_ADDR_BITS
]
265 # Read a tag from a tag memory row
266 def read_tag(way
, tagset
):
267 return tagset
.word_select(way
, TAG_WIDTH
)[:TAG_BITS
]
269 # Read a TLB tag from a TLB tag memory row
270 def read_tlb_tag(way
, tags
):
271 return tags
.word_select(way
, TLB_EA_TAG_BITS
)
273 # Write a TLB tag to a TLB tag memory row
274 def write_tlb_tag(way
, tags
, tag
):
275 return read_tlb_tag(way
, tags
).eq(tag
)
277 # Read a PTE from a TLB PTE memory row
278 def read_tlb_pte(way
, ptes
):
279 return ptes
.word_select(way
, TLB_PTE_BITS
)
281 def write_tlb_pte(way
, ptes
, newpte
):
282 return read_tlb_pte(way
, ptes
).eq(newpte
)
285 # Record for storing permission, attribute, etc. bits from a PTE
286 class PermAttr(RecordObject
):
287 def __init__(self
, name
=None):
288 super().__init
__(name
=name
)
289 self
.reference
= Signal()
290 self
.changed
= Signal()
291 self
.nocache
= Signal()
293 self
.rd_perm
= Signal()
294 self
.wr_perm
= Signal()
297 def extract_perm_attr(pte
):
302 # Type of operation on a "valid" input
306 OP_BAD
= 1 # NC cache hit, TLB miss, prot/RC failure
307 OP_STCX_FAIL
= 2 # conditional store w/o reservation
308 OP_LOAD_HIT
= 3 # Cache hit on load
309 OP_LOAD_MISS
= 4 # Load missing cache
310 OP_LOAD_NC
= 5 # Non-cachable load
311 OP_STORE_HIT
= 6 # Store hitting cache
312 OP_STORE_MISS
= 7 # Store missing cache
315 # Cache state machine
318 IDLE
= 0 # Normal load hit processing
319 RELOAD_WAIT_ACK
= 1 # Cache reload wait ack
320 STORE_WAIT_ACK
= 2 # Store wait ack
321 NC_LOAD_WAIT_ACK
= 3 # Non-cachable load wait ack
326 # In order to make timing, we use the BRAMs with
327 # an output buffer, which means that the BRAM
328 # output is delayed by an extra cycle.
330 # Thus, the dcache has a 2-stage internal pipeline
331 # for cache hits with no stalls.
333 # All other operations are handled via stalling
334 # in the first stage.
336 # The second stage can thus complete a hit at the same
337 # time as the first stage emits a stall for a complex op.
339 # Stage 0 register, basically contains just the latched request
341 class RegStage0(RecordObject
):
342 def __init__(self
, name
=None):
343 super().__init
__(name
=name
)
344 self
.req
= LoadStore1ToDCacheType(name
="lsmem")
345 self
.tlbie
= Signal() # indicates a tlbie request (from MMU)
346 self
.doall
= Signal() # with tlbie, indicates flush whole TLB
347 self
.tlbld
= Signal() # indicates a TLB load request (from MMU)
348 self
.mmu_req
= Signal() # indicates source of request
349 self
.d_valid
= Signal() # indicates req.data is valid now
352 class MemAccessRequest(RecordObject
):
353 def __init__(self
, name
=None):
354 super().__init
__(name
=name
)
356 self
.valid
= Signal()
358 self
.real_addr
= Signal(REAL_ADDR_BITS
)
359 self
.data
= Signal(64)
360 self
.byte_sel
= Signal(8)
361 self
.hit_way
= Signal(WAY_BITS
)
362 self
.same_tag
= Signal()
363 self
.mmu_req
= Signal()
366 # First stage register, contains state for stage 1 of load hits
367 # and for the state machine used by all other operations
368 class RegStage1(RecordObject
):
369 def __init__(self
, name
=None):
370 super().__init
__(name
=name
)
371 # Info about the request
372 self
.full
= Signal() # have uncompleted request
373 self
.mmu_req
= Signal() # request is from MMU
374 self
.req
= MemAccessRequest(name
="reqmem")
377 self
.hit_way
= Signal(WAY_BITS
)
378 self
.hit_load_valid
= Signal()
379 self
.hit_index
= Signal(INDEX_BITS
)
380 self
.cache_hit
= Signal()
383 self
.tlb_hit
= TLBHit("tlb_hit")
384 self
.tlb_hit_index
= Signal(TLB_SET_BITS
)
386 # 2-stage data buffer for data forwarded from writes to reads
387 self
.forward_data1
= Signal(64)
388 self
.forward_data2
= Signal(64)
389 self
.forward_sel1
= Signal(8)
390 self
.forward_valid1
= Signal()
391 self
.forward_way1
= Signal(WAY_BITS
)
392 self
.forward_row1
= Signal(ROW_BITS
)
393 self
.use_forward1
= Signal()
394 self
.forward_sel
= Signal(8)
396 # Cache miss state (reload state machine)
397 self
.state
= Signal(State
)
399 self
.write_bram
= Signal()
400 self
.write_tag
= Signal()
401 self
.slow_valid
= Signal()
402 self
.wb
= WBMasterOut("wb")
403 self
.reload_tag
= Signal(TAG_BITS
)
404 self
.store_way
= Signal(WAY_BITS
)
405 self
.store_row
= Signal(ROW_BITS
)
406 self
.store_index
= Signal(INDEX_BITS
)
407 self
.end_row_ix
= Signal(ROW_LINE_BITS
)
408 self
.rows_valid
= RowPerLineValidArray()
409 self
.acks_pending
= Signal(3)
410 self
.inc_acks
= Signal()
411 self
.dec_acks
= Signal()
413 # Signals to complete (possibly with error)
414 self
.ls_valid
= Signal()
415 self
.ls_error
= Signal()
416 self
.mmu_done
= Signal()
417 self
.mmu_error
= Signal()
418 self
.cache_paradox
= Signal()
420 # Signal to complete a failed stcx.
421 self
.stcx_fail
= Signal()
424 # Reservation information
425 class Reservation(RecordObject
):
428 self
.valid
= Signal()
429 self
.addr
= Signal(64-LINE_OFF_BITS
)
432 class DTLBUpdate(Elaboratable
):
434 self
.tlbie
= Signal()
435 self
.tlbwe
= Signal()
436 self
.doall
= Signal()
437 self
.updated
= Signal()
438 self
.v_updated
= Signal()
439 self
.tlb_hit
= TLBHit("tlb_hit")
440 self
.tlb_req_index
= Signal(TLB_SET_BITS
)
442 self
.tlb_tag_way
= Signal(TLB_TAG_WAY_BITS
)
443 self
.tlb_pte_way
= Signal(TLB_PTE_WAY_BITS
)
444 self
.repl_way
= Signal(TLB_WAY_BITS
)
445 self
.eatag
= Signal(TLB_EA_TAG_BITS
)
446 self
.pte_data
= Signal(TLB_PTE_BITS
)
448 self
.dv
= Signal(TLB_NUM_WAYS
) # tlb_way_valids_t
450 self
.tb_out
= Signal(TLB_TAG_WAY_BITS
) # tlb_way_tags_t
451 self
.db_out
= Signal(TLB_NUM_WAYS
) # tlb_way_valids_t
452 self
.pb_out
= Signal(TLB_PTE_WAY_BITS
) # tlb_way_ptes_t
454 def elaborate(self
, platform
):
459 tagset
= Signal(TLB_TAG_WAY_BITS
)
460 pteset
= Signal(TLB_PTE_WAY_BITS
)
462 tb_out
, pb_out
, db_out
= self
.tb_out
, self
.pb_out
, self
.db_out
463 comb
+= db_out
.eq(self
.dv
)
465 with m
.If(self
.tlbie
& self
.doall
):
466 pass # clear all back in parent
467 with m
.Elif(self
.tlbie
):
468 with m
.If(self
.tlb_hit
.valid
):
469 comb
+= db_out
.bit_select(self
.tlb_hit
.way
, 1).eq(0)
470 comb
+= self
.v_updated
.eq(1)
472 with m
.Elif(self
.tlbwe
):
474 comb
+= tagset
.eq(self
.tlb_tag_way
)
475 comb
+= write_tlb_tag(self
.repl_way
, tagset
, self
.eatag
)
476 comb
+= tb_out
.eq(tagset
)
478 comb
+= pteset
.eq(self
.tlb_pte_way
)
479 comb
+= write_tlb_pte(self
.repl_way
, pteset
, self
.pte_data
)
480 comb
+= pb_out
.eq(pteset
)
482 comb
+= db_out
.bit_select(self
.repl_way
, 1).eq(1)
484 comb
+= self
.updated
.eq(1)
485 comb
+= self
.v_updated
.eq(1)
490 class DCachePendingHit(Elaboratable
):
492 def __init__(self
, tlb_way
,
493 cache_i_validdx
, cache_tag_set
,
498 self
.virt_mode
= Signal()
499 self
.is_hit
= Signal()
500 self
.tlb_hit
= TLBHit("tlb_hit")
501 self
.hit_way
= Signal(WAY_BITS
)
502 self
.rel_match
= Signal()
503 self
.req_index
= Signal(INDEX_BITS
)
504 self
.reload_tag
= Signal(TAG_BITS
)
506 self
.tlb_way
= tlb_way
507 self
.cache_i_validdx
= cache_i_validdx
508 self
.cache_tag_set
= cache_tag_set
509 self
.req_addr
= req_addr
510 self
.hit_set
= hit_set
512 def elaborate(self
, platform
):
518 virt_mode
= self
.virt_mode
520 tlb_way
= self
.tlb_way
521 cache_i_validdx
= self
.cache_i_validdx
522 cache_tag_set
= self
.cache_tag_set
523 req_addr
= self
.req_addr
524 tlb_hit
= self
.tlb_hit
525 hit_set
= self
.hit_set
526 hit_way
= self
.hit_way
527 rel_match
= self
.rel_match
528 req_index
= self
.req_index
529 reload_tag
= self
.reload_tag
531 rel_matches
= Array(Signal(name
="rel_matches_%d" % i
) \
532 for i
in range(TLB_NUM_WAYS
))
533 hit_way_set
= HitWaySet()
535 # Test if pending request is a hit on any way
536 # In order to make timing in virtual mode,
537 # when we are using the TLB, we compare each
538 # way with each of the real addresses from each way of
539 # the TLB, and then decide later which match to use.
541 with m
.If(virt_mode
):
542 for j
in range(TLB_NUM_WAYS
): # tlb_num_way_t
543 s_tag
= Signal(TAG_BITS
, name
="s_tag%d" % j
)
545 s_pte
= Signal(TLB_PTE_BITS
)
546 s_ra
= Signal(REAL_ADDR_BITS
)
547 comb
+= s_pte
.eq(read_tlb_pte(j
, tlb_way
.pte
))
548 comb
+= s_ra
.eq(Cat(req_addr
[0:TLB_LG_PGSZ
],
549 s_pte
[TLB_LG_PGSZ
:REAL_ADDR_BITS
]))
550 comb
+= s_tag
.eq(get_tag(s_ra
))
552 for i
in range(NUM_WAYS
): # way_t
553 is_tag_hit
= Signal(name
="is_tag_hit_%d_%d" % (j
, i
))
554 comb
+= is_tag_hit
.eq(go
& cache_i_validdx
[i
] &
555 (read_tag(i
, cache_tag_set
) == s_tag
)
556 & (tlb_way
.valid
[j
]))
557 with m
.If(is_tag_hit
):
558 comb
+= hit_way_set
[j
].eq(i
)
560 comb
+= hit_set
[j
].eq(s_hit
)
561 with m
.If(s_tag
== reload_tag
):
562 comb
+= rel_matches
[j
].eq(1)
563 with m
.If(tlb_hit
.way
):
564 comb
+= is_hit
.eq(hit_set
[tlb_hit
.way
])
565 comb
+= hit_way
.eq(hit_way_set
[tlb_hit
.way
])
566 comb
+= rel_match
.eq(rel_matches
[tlb_hit
.way
])
568 s_tag
= Signal(TAG_BITS
)
569 comb
+= s_tag
.eq(get_tag(req_addr
))
570 for i
in range(NUM_WAYS
): # way_t
571 is_tag_hit
= Signal(name
="is_tag_hit_%d" % i
)
572 comb
+= is_tag_hit
.eq(go
& cache_i_validdx
[i
] &
573 (read_tag(i
, cache_tag_set
) == s_tag
))
574 with m
.If(is_tag_hit
):
575 comb
+= hit_way
.eq(i
)
577 with m
.If(s_tag
== reload_tag
):
578 comb
+= rel_match
.eq(1)
583 class DCache(Elaboratable
):
584 """Set associative dcache write-through
586 TODO (in no specific order):
587 * See list in icache.vhdl
588 * Complete load misses on the cycle when WB data comes instead of
589 at the end of line (this requires dealing with requests coming in
593 self
.d_in
= LoadStore1ToDCacheType("d_in")
594 self
.d_out
= DCacheToLoadStore1Type("d_out")
596 self
.m_in
= MMUToDCacheType("m_in")
597 self
.m_out
= DCacheToMMUType("m_out")
599 self
.stall_out
= Signal()
601 # standard naming (wired to non-standard for compatibility)
602 self
.bus
= Interface(addr_width
=32,
609 self
.log_out
= Signal(20)
611 def stage_0(self
, m
, r0
, r1
, r0_full
):
612 """Latch the request in r0.req as long as we're not stalling
616 d_in
, d_out
, m_in
= self
.d_in
, self
.d_out
, self
.m_in
618 r
= RegStage0("stage0")
620 # TODO, this goes in unit tests and formal proofs
621 with m
.If(d_in
.valid
& m_in
.valid
):
622 sync
+= Display("request collision loadstore vs MMU")
624 with m
.If(m_in
.valid
):
625 comb
+= r
.req
.valid
.eq(1)
626 comb
+= r
.req
.load
.eq(~
(m_in
.tlbie | m_in
.tlbld
))# no invalidate
627 comb
+= r
.req
.dcbz
.eq(0)
628 comb
+= r
.req
.nc
.eq(0)
629 comb
+= r
.req
.reserve
.eq(0)
630 comb
+= r
.req
.virt_mode
.eq(0)
631 comb
+= r
.req
.priv_mode
.eq(1)
632 comb
+= r
.req
.addr
.eq(m_in
.addr
)
633 comb
+= r
.req
.data
.eq(m_in
.pte
)
634 comb
+= r
.req
.byte_sel
.eq(~
0) # Const -1 sets all to 0b111....
635 comb
+= r
.tlbie
.eq(m_in
.tlbie
)
636 comb
+= r
.doall
.eq(m_in
.doall
)
637 comb
+= r
.tlbld
.eq(m_in
.tlbld
)
638 comb
+= r
.mmu_req
.eq(1)
639 m
.d
.sync
+= Display(" DCACHE req mmu addr %x pte %x ld %d",
640 m_in
.addr
, m_in
.pte
, r
.req
.load
)
643 comb
+= r
.req
.eq(d_in
)
644 comb
+= r
.req
.data
.eq(0)
645 comb
+= r
.tlbie
.eq(0)
646 comb
+= r
.doall
.eq(0)
647 comb
+= r
.tlbld
.eq(0)
648 comb
+= r
.mmu_req
.eq(0)
649 with m
.If((~r1
.full
& ~d_in
.hold
) | ~r0_full
):
651 sync
+= r0_full
.eq(r
.req
.valid
)
652 # Sample data the cycle after a request comes in from loadstore1.
653 # If another request has come in already then the data will get
654 # put directly into req.data below.
655 with m
.If(r0
.req
.valid
& ~r
.req
.valid
& ~r0
.d_valid
&
657 sync
+= r0
.req
.data
.eq(d_in
.data
)
658 sync
+= r0
.d_valid
.eq(1)
659 with m
.If(d_in
.valid
):
660 m
.d
.sync
+= Display(" DCACHE req cache "
661 "virt %d addr %x data %x ld %d",
662 r
.req
.virt_mode
, r
.req
.addr
,
663 r
.req
.data
, r
.req
.load
)
665 def tlb_read(self
, m
, r0_stall
, tlb_way
, dtlb
):
667 Operates in the second cycle on the request latched in r0.req.
668 TLB updates write the entry at the end of the second cycle.
672 m_in
, d_in
= self
.m_in
, self
.d_in
674 index
= Signal(TLB_SET_BITS
)
675 addrbits
= Signal(TLB_SET_BITS
)
678 amax
= TLB_LG_PGSZ
+ TLB_SET_BITS
680 with m
.If(m_in
.valid
):
681 comb
+= addrbits
.eq(m_in
.addr
[amin
: amax
])
683 comb
+= addrbits
.eq(d_in
.addr
[amin
: amax
])
684 comb
+= index
.eq(addrbits
)
686 # If we have any op and the previous op isn't finished,
687 # then keep the same output for next cycle.
688 with m
.If(~r0_stall
):
689 sync
+= tlb_way
.eq(dtlb
[index
])
691 def maybe_tlb_plrus(self
, m
, r1
, tlb_plru_victim
):
692 """Generate TLB PLRUs
697 if TLB_NUM_WAYS
== 0:
700 # Binary-to-Unary one-hot, enabled by tlb_hit valid
701 tlb_plrus
= PLRUs(TLB_SET_SIZE
, TLB_WAY_BITS
, tlb_plru_victim
)
702 m
.submodules
.tlb_plrus
= tlb_plrus
703 comb
+= tlb_plrus
.way
.eq(r1
.tlb_hit
.way
)
704 comb
+= tlb_plrus
.valid
.eq(r1
.tlb_hit
.valid
)
705 comb
+= tlb_plrus
.index
.eq(r1
.tlb_hit_index
)
707 def tlb_search(self
, m
, tlb_req_index
, r0
, r0_valid
,
709 pte
, tlb_hit
, valid_ra
, perm_attr
, ra
):
713 hitway
= Signal(TLB_WAY_BITS
)
715 eatag
= Signal(TLB_EA_TAG_BITS
)
717 TLB_LG_END
= TLB_LG_PGSZ
+ TLB_SET_BITS
718 comb
+= tlb_req_index
.eq(r0
.req
.addr
[TLB_LG_PGSZ
: TLB_LG_END
])
719 comb
+= eatag
.eq(r0
.req
.addr
[TLB_LG_END
: 64 ])
721 for i
in range(TLB_NUM_WAYS
):
722 is_tag_hit
= Signal(name
="is_tag_hit%d" % i
)
723 tlb_tag
= Signal(TLB_EA_TAG_BITS
, name
="tlb_tag%d" % i
)
724 comb
+= tlb_tag
.eq(read_tlb_tag(i
, tlb_way
.tag
))
725 comb
+= is_tag_hit
.eq((tlb_way
.valid
[i
]) & (tlb_tag
== eatag
))
726 with m
.If(is_tag_hit
):
730 comb
+= tlb_hit
.valid
.eq(hit
& r0_valid
)
731 comb
+= tlb_hit
.way
.eq(hitway
)
733 with m
.If(tlb_hit
.valid
):
734 comb
+= pte
.eq(read_tlb_pte(hitway
, tlb_way
.pte
))
735 comb
+= valid_ra
.eq(tlb_hit
.valid | ~r0
.req
.virt_mode
)
737 with m
.If(r0
.req
.virt_mode
):
738 comb
+= ra
.eq(Cat(Const(0, ROW_OFF_BITS
),
739 r0
.req
.addr
[ROW_OFF_BITS
:TLB_LG_PGSZ
],
740 pte
[TLB_LG_PGSZ
:REAL_ADDR_BITS
]))
741 comb
+= perm_attr
.reference
.eq(pte
[8])
742 comb
+= perm_attr
.changed
.eq(pte
[7])
743 comb
+= perm_attr
.nocache
.eq(pte
[5])
744 comb
+= perm_attr
.priv
.eq(pte
[3])
745 comb
+= perm_attr
.rd_perm
.eq(pte
[2])
746 comb
+= perm_attr
.wr_perm
.eq(pte
[1])
748 comb
+= ra
.eq(Cat(Const(0, ROW_OFF_BITS
),
749 r0
.req
.addr
[ROW_OFF_BITS
:REAL_ADDR_BITS
]))
750 comb
+= perm_attr
.reference
.eq(1)
751 comb
+= perm_attr
.changed
.eq(1)
752 comb
+= perm_attr
.nocache
.eq(0)
753 comb
+= perm_attr
.priv
.eq(1)
754 comb
+= perm_attr
.rd_perm
.eq(1)
755 comb
+= perm_attr
.wr_perm
.eq(1)
758 m
.d
.sync
+= Display("DCACHE virt mode %d hit %d ra %x pte %x",
759 r0
.req
.virt_mode
, tlb_hit
.valid
, ra
, pte
)
760 m
.d
.sync
+= Display(" perm ref=%d", perm_attr
.reference
)
761 m
.d
.sync
+= Display(" perm chg=%d", perm_attr
.changed
)
762 m
.d
.sync
+= Display(" perm noc=%d", perm_attr
.nocache
)
763 m
.d
.sync
+= Display(" perm prv=%d", perm_attr
.priv
)
764 m
.d
.sync
+= Display(" perm rdp=%d", perm_attr
.rd_perm
)
765 m
.d
.sync
+= Display(" perm wrp=%d", perm_attr
.wr_perm
)
767 def tlb_update(self
, m
, r0_valid
, r0
, dtlb
, tlb_req_index
,
768 tlb_hit
, tlb_plru_victim
, tlb_way
):
776 comb
+= tlbie
.eq(r0_valid
& r0
.tlbie
)
777 comb
+= tlbwe
.eq(r0_valid
& r0
.tlbld
)
779 m
.submodules
.tlb_update
= d
= DTLBUpdate()
780 with m
.If(tlbie
& r0
.doall
):
781 # clear all valid bits at once
782 for i
in range(TLB_SET_SIZE
):
783 sync
+= dtlb
[i
].valid
.eq(0)
784 with m
.If(d
.updated
):
785 sync
+= dtlb
[tlb_req_index
].tag
.eq(d
.tb_out
)
786 sync
+= dtlb
[tlb_req_index
].pte
.eq(d
.pb_out
)
787 with m
.If(d
.v_updated
):
788 sync
+= dtlb
[tlb_req_index
].valid
.eq(d
.db_out
)
790 comb
+= d
.dv
.eq(dtlb
[tlb_req_index
].valid
)
792 comb
+= d
.tlbie
.eq(tlbie
)
793 comb
+= d
.tlbwe
.eq(tlbwe
)
794 comb
+= d
.doall
.eq(r0
.doall
)
795 comb
+= d
.tlb_hit
.eq(tlb_hit
)
796 comb
+= d
.tlb_tag_way
.eq(tlb_way
.tag
)
797 comb
+= d
.tlb_pte_way
.eq(tlb_way
.pte
)
798 comb
+= d
.tlb_req_index
.eq(tlb_req_index
)
800 with m
.If(tlb_hit
.valid
):
801 comb
+= d
.repl_way
.eq(tlb_hit
.way
)
803 comb
+= d
.repl_way
.eq(tlb_plru_victim
[tlb_req_index
])
804 comb
+= d
.eatag
.eq(r0
.req
.addr
[TLB_LG_PGSZ
+ TLB_SET_BITS
:64])
805 comb
+= d
.pte_data
.eq(r0
.req
.data
)
807 def maybe_plrus(self
, m
, r1
, plru_victim
):
813 if TLB_NUM_WAYS
== 0:
816 m
.submodules
.plrus
= plrus
= PLRUs(NUM_LINES
, WAY_BITS
, plru_victim
)
817 comb
+= plrus
.way
.eq(r1
.hit_way
)
818 comb
+= plrus
.valid
.eq(r1
.cache_hit
)
819 comb
+= plrus
.index
.eq(r1
.hit_index
)
821 def cache_tag_read(self
, m
, r0_stall
, req_index
, cache_tag_set
, cache_tags
):
822 """Cache tag RAM read port
826 m_in
, d_in
= self
.m_in
, self
.d_in
828 index
= Signal(INDEX_BITS
)
831 comb
+= index
.eq(req_index
)
832 with m
.Elif(m_in
.valid
):
833 comb
+= index
.eq(get_index(m_in
.addr
))
835 comb
+= index
.eq(get_index(d_in
.addr
))
836 sync
+= cache_tag_set
.eq(cache_tags
[index
].tag
)
838 def dcache_request(self
, m
, r0
, ra
, req_index
, req_row
, req_tag
,
839 r0_valid
, r1
, cache_tags
, replace_way
,
840 use_forward1_next
, use_forward2_next
,
841 req_hit_way
, plru_victim
, rc_ok
, perm_attr
,
842 valid_ra
, perm_ok
, access_ok
, req_op
, req_go
,
843 tlb_hit
, tlb_way
, cache_tag_set
,
844 cancel_store
, req_same_tag
, r0_stall
, early_req_row
):
845 """Cache request parsing and hit detection
849 m_in
, d_in
= self
.m_in
, self
.d_in
852 hit_way
= Signal(WAY_BITS
)
857 hit_set
= Array(Signal(name
="hit_set_%d" % i
) \
858 for i
in range(TLB_NUM_WAYS
))
859 cache_i_validdx
= Signal(NUM_WAYS
)
861 # Extract line, row and tag from request
862 comb
+= req_index
.eq(get_index(r0
.req
.addr
))
863 comb
+= req_row
.eq(get_row(r0
.req
.addr
))
864 comb
+= req_tag
.eq(get_tag(ra
))
866 if False: # display on comb is a bit... busy.
867 comb
+= Display("dcache_req addr:%x ra: %x idx: %x tag: %x row: %x",
868 r0
.req
.addr
, ra
, req_index
, req_tag
, req_row
)
870 comb
+= go
.eq(r0_valid
& ~
(r0
.tlbie | r0
.tlbld
) & ~r1
.ls_error
)
871 comb
+= cache_i_validdx
.eq(cache_tags
[req_index
].valid
)
873 m
.submodules
.dcache_pend
= dc
= DCachePendingHit(tlb_way
,
874 cache_i_validdx
, cache_tag_set
,
877 comb
+= dc
.tlb_hit
.eq(tlb_hit
)
878 comb
+= dc
.reload_tag
.eq(r1
.reload_tag
)
879 comb
+= dc
.virt_mode
.eq(r0
.req
.virt_mode
)
881 comb
+= dc
.req_index
.eq(req_index
)
883 comb
+= is_hit
.eq(dc
.is_hit
)
884 comb
+= hit_way
.eq(dc
.hit_way
)
885 comb
+= req_same_tag
.eq(dc
.rel_match
)
887 # See if the request matches the line currently being reloaded
888 with m
.If((r1
.state
== State
.RELOAD_WAIT_ACK
) &
889 (req_index
== r1
.store_index
) & req_same_tag
):
890 # For a store, consider this a hit even if the row isn't
891 # valid since it will be by the time we perform the store.
892 # For a load, check the appropriate row valid bit.
893 rrow
= Signal(ROW_LINE_BITS
)
894 comb
+= rrow
.eq(req_row
)
895 valid
= r1
.rows_valid
[rrow
]
896 comb
+= is_hit
.eq((~r0
.req
.load
) | valid
)
897 comb
+= hit_way
.eq(replace_way
)
899 # Whether to use forwarded data for a load or not
900 with m
.If((get_row(r1
.req
.real_addr
) == req_row
) &
901 (r1
.req
.hit_way
== hit_way
)):
902 # Only need to consider r1.write_bram here, since if we
903 # are writing refill data here, then we don't have a
904 # cache hit this cycle on the line being refilled.
905 # (There is the possibility that the load following the
906 # load miss that started the refill could be to the old
907 # contents of the victim line, since it is a couple of
908 # cycles after the refill starts before we see the updated
909 # cache tag. In that case we don't use the bypass.)
910 comb
+= use_forward1_next
.eq(r1
.write_bram
)
911 with m
.If((r1
.forward_row1
== req_row
) & (r1
.forward_way1
== hit_way
)):
912 comb
+= use_forward2_next
.eq(r1
.forward_valid1
)
914 # The way that matched on a hit
915 comb
+= req_hit_way
.eq(hit_way
)
917 # The way to replace on a miss
918 with m
.If(r1
.write_tag
):
919 comb
+= replace_way
.eq(plru_victim
[r1
.store_index
])
921 comb
+= replace_way
.eq(r1
.store_way
)
923 # work out whether we have permission for this access
924 # NB we don't yet implement AMR, thus no KUAP
925 comb
+= rc_ok
.eq(perm_attr
.reference
926 & (r0
.req
.load | perm_attr
.changed
))
927 comb
+= perm_ok
.eq((r0
.req
.priv_mode |
(~perm_attr
.priv
)) &
929 (r0
.req
.load
& perm_attr
.rd_perm
)))
930 comb
+= access_ok
.eq(valid_ra
& perm_ok
& rc_ok
)
932 # Combine the request and cache hit status to decide what
933 # operation needs to be done
934 comb
+= nc
.eq(r0
.req
.nc | perm_attr
.nocache
)
935 comb
+= op
.eq(Op
.OP_NONE
)
937 with m
.If(~access_ok
):
938 m
.d
.sync
+= Display("DCACHE access fail valid_ra=%d p=%d rc=%d",
939 valid_ra
, perm_ok
, rc_ok
)
940 comb
+= op
.eq(Op
.OP_BAD
)
941 with m
.Elif(cancel_store
):
942 m
.d
.sync
+= Display("DCACHE cancel store")
943 comb
+= op
.eq(Op
.OP_STCX_FAIL
)
945 m
.d
.sync
+= Display("DCACHE valid_ra=%d nc=%d ld=%d",
946 valid_ra
, nc
, r0
.req
.load
)
947 comb
+= opsel
.eq(Cat(is_hit
, nc
, r0
.req
.load
))
948 with m
.Switch(opsel
):
949 with m
.Case(0b101): comb
+= op
.eq(Op
.OP_LOAD_HIT
)
950 with m
.Case(0b100): comb
+= op
.eq(Op
.OP_LOAD_MISS
)
951 with m
.Case(0b110): comb
+= op
.eq(Op
.OP_LOAD_NC
)
952 with m
.Case(0b001): comb
+= op
.eq(Op
.OP_STORE_HIT
)
953 with m
.Case(0b000): comb
+= op
.eq(Op
.OP_STORE_MISS
)
954 with m
.Case(0b010): comb
+= op
.eq(Op
.OP_STORE_MISS
)
955 with m
.Case(0b011): comb
+= op
.eq(Op
.OP_BAD
)
956 with m
.Case(0b111): comb
+= op
.eq(Op
.OP_BAD
)
957 comb
+= req_op
.eq(op
)
958 comb
+= req_go
.eq(go
)
960 # Version of the row number that is valid one cycle earlier
961 # in the cases where we need to read the cache data BRAM.
962 # If we're stalling then we need to keep reading the last
964 with m
.If(~r0_stall
):
965 with m
.If(m_in
.valid
):
966 comb
+= early_req_row
.eq(get_row(m_in
.addr
))
968 comb
+= early_req_row
.eq(get_row(d_in
.addr
))
970 comb
+= early_req_row
.eq(req_row
)
972 def reservation_comb(self
, m
, cancel_store
, set_rsrv
, clear_rsrv
,
973 r0_valid
, r0
, reservation
):
974 """Handle load-with-reservation and store-conditional instructions
978 with m
.If(r0_valid
& r0
.req
.reserve
):
979 # XXX generate alignment interrupt if address
980 # is not aligned XXX or if r0.req.nc = '1'
981 with m
.If(r0
.req
.load
):
982 comb
+= set_rsrv
.eq(r0
.req
.atomic_last
) # load with reservation
984 comb
+= clear_rsrv
.eq(r0
.req
.atomic_last
) # store conditional
985 with m
.If((~reservation
.valid
) |
986 (r0
.req
.addr
[LINE_OFF_BITS
:64] != reservation
.addr
)):
987 comb
+= cancel_store
.eq(1)
989 def reservation_reg(self
, m
, r0_valid
, access_ok
, set_rsrv
, clear_rsrv
,
994 with m
.If(r0_valid
& access_ok
):
995 with m
.If(clear_rsrv
):
996 sync
+= reservation
.valid
.eq(0)
997 with m
.Elif(set_rsrv
):
998 sync
+= reservation
.valid
.eq(1)
999 sync
+= reservation
.addr
.eq(r0
.req
.addr
[LINE_OFF_BITS
:64])
1001 def writeback_control(self
, m
, r1
, cache_out_row
):
1002 """Return data for loads & completion control logic
1006 d_out
, m_out
= self
.d_out
, self
.m_out
1008 data_out
= Signal(64)
1009 data_fwd
= Signal(64)
1011 # Use the bypass if are reading the row that was
1012 # written 1 or 2 cycles ago, including for the
1013 # slow_valid = 1 case (i.e. completing a load
1014 # miss or a non-cacheable load).
1015 with m
.If(r1
.use_forward1
):
1016 comb
+= data_fwd
.eq(r1
.forward_data1
)
1018 comb
+= data_fwd
.eq(r1
.forward_data2
)
1020 comb
+= data_out
.eq(cache_out_row
)
1023 with m
.If(r1
.forward_sel
[i
]):
1024 dsel
= data_fwd
.word_select(i
, 8)
1025 comb
+= data_out
.word_select(i
, 8).eq(dsel
)
1027 # DCache output to LoadStore
1028 comb
+= d_out
.valid
.eq(r1
.ls_valid
)
1029 comb
+= d_out
.data
.eq(data_out
)
1030 comb
+= d_out
.store_done
.eq(~r1
.stcx_fail
)
1031 comb
+= d_out
.error
.eq(r1
.ls_error
)
1032 comb
+= d_out
.cache_paradox
.eq(r1
.cache_paradox
)
1035 comb
+= m_out
.done
.eq(r1
.mmu_done
)
1036 comb
+= m_out
.err
.eq(r1
.mmu_error
)
1037 comb
+= m_out
.data
.eq(data_out
)
1039 # We have a valid load or store hit or we just completed
1040 # a slow op such as a load miss, a NC load or a store
1042 # Note: the load hit is delayed by one cycle. However it
1043 # can still not collide with r.slow_valid (well unless I
1044 # miscalculated) because slow_valid can only be set on a
1045 # subsequent request and not on its first cycle (the state
1046 # machine must have advanced), which makes slow_valid
1047 # at least 2 cycles from the previous hit_load_valid.
1049 # Sanity: Only one of these must be set in any given cycle
1051 if False: # TODO: need Display to get this to work
1052 assert (r1
.slow_valid
& r1
.stcx_fail
) != 1, \
1053 "unexpected slow_valid collision with stcx_fail"
1055 assert ((r1
.slow_valid | r1
.stcx_fail
) | r1
.hit_load_valid
) != 1, \
1056 "unexpected hit_load_delayed collision with slow_valid"
1058 with m
.If(~r1
.mmu_req
):
1059 # Request came from loadstore1...
1060 # Load hit case is the standard path
1061 with m
.If(r1
.hit_load_valid
):
1062 sync
+= Display("completing load hit data=%x", data_out
)
1064 # error cases complete without stalling
1065 with m
.If(r1
.ls_error
):
1067 sync
+= Display("completing dcbz with error")
1069 sync
+= Display("completing ld/st with error")
1071 # Slow ops (load miss, NC, stores)
1072 with m
.If(r1
.slow_valid
):
1073 sync
+= Display("completing store or load miss adr=%x data=%x",
1074 r1
.req
.real_addr
, data_out
)
1077 # Request came from MMU
1078 with m
.If(r1
.hit_load_valid
):
1079 sync
+= Display("completing load hit to MMU, data=%x",
1081 # error cases complete without stalling
1082 with m
.If(r1
.mmu_error
):
1083 sync
+= Display("combpleting MMU ld with error")
1085 # Slow ops (i.e. load miss)
1086 with m
.If(r1
.slow_valid
):
1087 sync
+= Display("completing MMU load miss, adr=%x data=%x",
1088 r1
.req
.real_addr
, m_out
.data
)
1090 def rams(self
, m
, r1
, early_req_row
, cache_out_row
, replace_way
):
1092 Generate a cache RAM for each way. This handles the normal
1093 reads, writes from reloads and the special store-hit update
1096 Note: the BRAMs have an extra read buffer, meaning the output
1097 is pipelined an extra cycle. This differs from the
1098 icache. The writeback logic needs to take that into
1099 account by using 1-cycle delayed signals for load hits.
1104 # a Binary-to-Unary one-hots here. replace-way one-hot is gated
1105 # (enabled) by bus.ack, not-write-bram, and state RELOAD_WAIT_ACK
1106 m
.submodules
.rams_replace_way_e
= rwe
= Decoder(NUM_WAYS
)
1107 comb
+= rwe
.n
.eq(~
((r1
.state
== State
.RELOAD_WAIT_ACK
) & bus
.ack
&
1109 comb
+= rwe
.i
.eq(replace_way
)
1111 m
.submodules
.rams_hit_way_e
= hwe
= Decoder(NUM_WAYS
)
1112 comb
+= hwe
.i
.eq(r1
.hit_way
)
1114 # this one is gated with write_bram, and replace_way_e can never be
1115 # set at the same time. that means that do_write can OR the outputs
1116 m
.submodules
.rams_hit_req_way_e
= hre
= Decoder(NUM_WAYS
)
1117 comb
+= hre
.n
.eq(~r1
.write_bram
) # Decoder.n is inverted
1118 comb
+= hre
.i
.eq(r1
.req
.hit_way
)
1121 comb
+= do_read
.eq(1)
1123 for i
in range(NUM_WAYS
):
1124 rd_addr
= Signal(ROW_BITS
, name
="rd_addr_%d" % i
)
1125 do_write
= Signal(name
="do_wr%d" % i
)
1126 wr_addr
= Signal(ROW_BITS
, name
="wr_addr_%d" % i
)
1127 wr_data
= Signal(WB_DATA_BITS
, name
="din_%d" % i
)
1128 wr_sel
= Signal(ROW_SIZE
)
1129 wr_sel_m
= Signal(ROW_SIZE
)
1130 _d_out
= Signal(WB_DATA_BITS
, name
="dout_%d" % i
) # cache_row_t
1132 way
= CacheRam(ROW_BITS
, WB_DATA_BITS
, ADD_BUF
=True, ram_num
=i
)
1133 setattr(m
.submodules
, "cacheram_%d" % i
, way
)
1135 comb
+= way
.rd_en
.eq(do_read
)
1136 comb
+= way
.rd_addr
.eq(rd_addr
)
1137 comb
+= _d_out
.eq(way
.rd_data_o
)
1138 comb
+= way
.wr_sel
.eq(wr_sel_m
)
1139 comb
+= way
.wr_addr
.eq(wr_addr
)
1140 comb
+= way
.wr_data
.eq(wr_data
)
1143 comb
+= rd_addr
.eq(early_req_row
)
1144 with m
.If(hwe
.o
[i
]):
1145 comb
+= cache_out_row
.eq(_d_out
)
1149 # Defaults to wishbone read responses (cache refill)
1151 # For timing, the mux on wr_data/sel/addr is not
1152 # dependent on anything other than the current state.
1154 with m
.If(r1
.write_bram
):
1155 # Write store data to BRAM. This happens one
1156 # cycle after the store is in r0.
1157 comb
+= wr_data
.eq(r1
.req
.data
)
1158 comb
+= wr_sel
.eq(r1
.req
.byte_sel
)
1159 comb
+= wr_addr
.eq(get_row(r1
.req
.real_addr
))
1162 # Otherwise, we might be doing a reload or a DCBZ
1164 comb
+= wr_data
.eq(0)
1166 comb
+= wr_data
.eq(bus
.dat_r
)
1167 comb
+= wr_addr
.eq(r1
.store_row
)
1168 comb
+= wr_sel
.eq(~
0) # all 1s
1170 # these are mutually-exclusive via their Decoder-enablers
1171 # (note: Decoder-enable is inverted)
1172 comb
+= do_write
.eq(hre
.o
[i
] | rwe
.o
[i
])
1174 # Mask write selects with do_write since BRAM
1175 # doesn't have a global write-enable
1176 with m
.If(do_write
):
1177 comb
+= wr_sel_m
.eq(wr_sel
)
1179 # Cache hit synchronous machine for the easy case.
1180 # This handles load hits.
1181 # It also handles error cases (TLB miss, cache paradox)
1182 def dcache_fast_hit(self
, m
, req_op
, r0_valid
, r0
, r1
,
1183 req_hit_way
, req_index
, req_tag
, access_ok
,
1184 tlb_hit
, tlb_req_index
):
1188 with m
.If(req_op
!= Op
.OP_NONE
):
1189 sync
+= Display("op:%d addr:%x nc: %d idx: %x tag: %x way: %x",
1190 req_op
, r0
.req
.addr
, r0
.req
.nc
,
1191 req_index
, req_tag
, req_hit_way
)
1193 with m
.If(r0_valid
):
1194 sync
+= r1
.mmu_req
.eq(r0
.mmu_req
)
1196 # Fast path for load/store hits.
1197 # Set signals for the writeback controls.
1198 sync
+= r1
.hit_way
.eq(req_hit_way
)
1199 sync
+= r1
.hit_index
.eq(req_index
)
1201 sync
+= r1
.hit_load_valid
.eq(req_op
== Op
.OP_LOAD_HIT
)
1202 sync
+= r1
.cache_hit
.eq((req_op
== Op
.OP_LOAD_HIT
) |
1203 (req_op
== Op
.OP_STORE_HIT
))
1205 with m
.If(req_op
== Op
.OP_BAD
):
1206 sync
+= Display("Signalling ld/st error "
1207 "ls_error=%i mmu_error=%i cache_paradox=%i",
1208 ~r0
.mmu_req
,r0
.mmu_req
,access_ok
)
1209 sync
+= r1
.ls_error
.eq(~r0
.mmu_req
)
1210 sync
+= r1
.mmu_error
.eq(r0
.mmu_req
)
1211 sync
+= r1
.cache_paradox
.eq(access_ok
)
1213 sync
+= r1
.ls_error
.eq(0)
1214 sync
+= r1
.mmu_error
.eq(0)
1215 sync
+= r1
.cache_paradox
.eq(0)
1217 sync
+= r1
.stcx_fail
.eq(req_op
== Op
.OP_STCX_FAIL
)
1219 # Record TLB hit information for updating TLB PLRU
1220 sync
+= r1
.tlb_hit
.eq(tlb_hit
)
1221 sync
+= r1
.tlb_hit_index
.eq(tlb_req_index
)
1223 # Memory accesses are handled by this state machine:
1225 # * Cache load miss/reload (in conjunction with "rams")
1226 # * Load hits for non-cachable forms
1227 # * Stores (the collision case is handled in "rams")
1229 # All wishbone requests generation is done here.
1230 # This machine operates at stage 1.
1231 def dcache_slow(self
, m
, r1
, use_forward1_next
, use_forward2_next
,
1233 req_hit_way
, req_same_tag
,
1234 r0_valid
, req_op
, cache_tags
, req_go
, ra
):
1241 req
= MemAccessRequest("mreq_ds")
1243 req_row
= Signal(ROW_BITS
)
1244 req_idx
= Signal(INDEX_BITS
)
1245 req_tag
= Signal(TAG_BITS
)
1246 comb
+= req_idx
.eq(get_index(req
.real_addr
))
1247 comb
+= req_row
.eq(get_row(req
.real_addr
))
1248 comb
+= req_tag
.eq(get_tag(req
.real_addr
))
1250 sync
+= r1
.use_forward1
.eq(use_forward1_next
)
1251 sync
+= r1
.forward_sel
.eq(0)
1253 with m
.If(use_forward1_next
):
1254 sync
+= r1
.forward_sel
.eq(r1
.req
.byte_sel
)
1255 with m
.Elif(use_forward2_next
):
1256 sync
+= r1
.forward_sel
.eq(r1
.forward_sel1
)
1258 sync
+= r1
.forward_data2
.eq(r1
.forward_data1
)
1259 with m
.If(r1
.write_bram
):
1260 sync
+= r1
.forward_data1
.eq(r1
.req
.data
)
1261 sync
+= r1
.forward_sel1
.eq(r1
.req
.byte_sel
)
1262 sync
+= r1
.forward_way1
.eq(r1
.req
.hit_way
)
1263 sync
+= r1
.forward_row1
.eq(get_row(r1
.req
.real_addr
))
1264 sync
+= r1
.forward_valid1
.eq(1)
1267 sync
+= r1
.forward_data1
.eq(0)
1269 sync
+= r1
.forward_data1
.eq(bus
.dat_r
)
1270 sync
+= r1
.forward_sel1
.eq(~
0) # all 1s
1271 sync
+= r1
.forward_way1
.eq(replace_way
)
1272 sync
+= r1
.forward_row1
.eq(r1
.store_row
)
1273 sync
+= r1
.forward_valid1
.eq(0)
1275 # One cycle pulses reset
1276 sync
+= r1
.slow_valid
.eq(0)
1277 sync
+= r1
.write_bram
.eq(0)
1278 sync
+= r1
.inc_acks
.eq(0)
1279 sync
+= r1
.dec_acks
.eq(0)
1281 sync
+= r1
.ls_valid
.eq(0)
1282 # complete tlbies and TLB loads in the third cycle
1283 sync
+= r1
.mmu_done
.eq(r0_valid
& (r0
.tlbie | r0
.tlbld
))
1285 with m
.If((req_op
== Op
.OP_LOAD_HIT
) |
(req_op
== Op
.OP_STCX_FAIL
)):
1286 with m
.If(~r0
.mmu_req
):
1287 sync
+= r1
.ls_valid
.eq(1)
1289 sync
+= r1
.mmu_done
.eq(1)
1291 with m
.If(r1
.write_tag
):
1292 # Store new tag in selected way
1293 replace_way_onehot
= Signal(NUM_WAYS
)
1294 comb
+= replace_way_onehot
.eq(1<<replace_way
)
1295 for i
in range(NUM_WAYS
):
1296 with m
.If(replace_way_onehot
[i
]):
1297 ct
= Signal(TAG_RAM_WIDTH
)
1298 comb
+= ct
.eq(cache_tags
[r1
.store_index
].tag
)
1299 comb
+= ct
.word_select(i
, TAG_WIDTH
).eq(r1
.reload_tag
)
1300 sync
+= cache_tags
[r1
.store_index
].tag
.eq(ct
)
1301 sync
+= r1
.store_way
.eq(replace_way
)
1302 sync
+= r1
.write_tag
.eq(0)
1304 # Take request from r1.req if there is one there,
1305 # else from req_op, ra, etc.
1307 comb
+= req
.eq(r1
.req
)
1309 comb
+= req
.op
.eq(req_op
)
1310 comb
+= req
.valid
.eq(req_go
)
1311 comb
+= req
.mmu_req
.eq(r0
.mmu_req
)
1312 comb
+= req
.dcbz
.eq(r0
.req
.dcbz
)
1313 comb
+= req
.real_addr
.eq(ra
)
1315 with m
.If(r0
.req
.dcbz
):
1316 # force data to 0 for dcbz
1317 comb
+= req
.data
.eq(0)
1318 with m
.Elif(r0
.d_valid
):
1319 comb
+= req
.data
.eq(r0
.req
.data
)
1321 comb
+= req
.data
.eq(d_in
.data
)
1323 # Select all bytes for dcbz
1324 # and for cacheable loads
1325 with m
.If(r0
.req
.dcbz |
(r0
.req
.load
& ~r0
.req
.nc
)):
1326 comb
+= req
.byte_sel
.eq(~
0) # all 1s
1328 comb
+= req
.byte_sel
.eq(r0
.req
.byte_sel
)
1329 comb
+= req
.hit_way
.eq(req_hit_way
)
1330 comb
+= req
.same_tag
.eq(req_same_tag
)
1332 # Store the incoming request from r0,
1333 # if it is a slow request
1334 # Note that r1.full = 1 implies req_op = OP_NONE
1335 with m
.If((req_op
== Op
.OP_LOAD_MISS
)
1336 |
(req_op
== Op
.OP_LOAD_NC
)
1337 |
(req_op
== Op
.OP_STORE_MISS
)
1338 |
(req_op
== Op
.OP_STORE_HIT
)):
1339 sync
+= r1
.req
.eq(req
)
1340 sync
+= r1
.full
.eq(1)
1342 # Main state machine
1343 with m
.Switch(r1
.state
):
1345 with m
.Case(State
.IDLE
):
1346 sync
+= r1
.wb
.adr
.eq(req
.real_addr
[ROW_LINE_BITS
:])
1347 sync
+= r1
.wb
.sel
.eq(req
.byte_sel
)
1348 sync
+= r1
.wb
.dat
.eq(req
.data
)
1349 sync
+= r1
.dcbz
.eq(req
.dcbz
)
1351 # Keep track of our index and way
1352 # for subsequent stores.
1353 sync
+= r1
.store_index
.eq(req_idx
)
1354 sync
+= r1
.store_row
.eq(req_row
)
1355 sync
+= r1
.end_row_ix
.eq(get_row_of_line(req_row
)-1)
1356 sync
+= r1
.reload_tag
.eq(req_tag
)
1357 sync
+= r1
.req
.same_tag
.eq(1)
1359 with m
.If(req
.op
== Op
.OP_STORE_HIT
):
1360 sync
+= r1
.store_way
.eq(req
.hit_way
)
1362 # Reset per-row valid bits,
1363 # ready for handling OP_LOAD_MISS
1364 for i
in range(ROW_PER_LINE
):
1365 sync
+= r1
.rows_valid
[i
].eq(0)
1367 with m
.If(req_op
!= Op
.OP_NONE
):
1368 sync
+= Display("cache op %d", req
.op
)
1370 with m
.Switch(req
.op
):
1371 with m
.Case(Op
.OP_LOAD_HIT
):
1372 # stay in IDLE state
1375 with m
.Case(Op
.OP_LOAD_MISS
):
1376 sync
+= Display("cache miss real addr: %x " \
1378 req
.real_addr
, req_row
, req_tag
)
1380 # Start the wishbone cycle
1381 sync
+= r1
.wb
.we
.eq(0)
1382 sync
+= r1
.wb
.cyc
.eq(1)
1383 sync
+= r1
.wb
.stb
.eq(1)
1385 # Track that we had one request sent
1386 sync
+= r1
.state
.eq(State
.RELOAD_WAIT_ACK
)
1387 sync
+= r1
.write_tag
.eq(1)
1389 with m
.Case(Op
.OP_LOAD_NC
):
1390 sync
+= r1
.wb
.cyc
.eq(1)
1391 sync
+= r1
.wb
.stb
.eq(1)
1392 sync
+= r1
.wb
.we
.eq(0)
1393 sync
+= r1
.state
.eq(State
.NC_LOAD_WAIT_ACK
)
1395 with m
.Case(Op
.OP_STORE_HIT
, Op
.OP_STORE_MISS
):
1396 with m
.If(~req
.dcbz
):
1397 sync
+= r1
.state
.eq(State
.STORE_WAIT_ACK
)
1398 sync
+= r1
.acks_pending
.eq(1)
1399 sync
+= r1
.full
.eq(0)
1400 sync
+= r1
.slow_valid
.eq(1)
1402 with m
.If(~req
.mmu_req
):
1403 sync
+= r1
.ls_valid
.eq(1)
1405 sync
+= r1
.mmu_done
.eq(1)
1407 with m
.If(req
.op
== Op
.OP_STORE_HIT
):
1408 sync
+= r1
.write_bram
.eq(1)
1410 # dcbz is handled much like a load miss except
1411 # that we are writing to memory instead of reading
1412 sync
+= r1
.state
.eq(State
.RELOAD_WAIT_ACK
)
1414 with m
.If(req
.op
== Op
.OP_STORE_MISS
):
1415 sync
+= r1
.write_tag
.eq(1)
1417 sync
+= r1
.wb
.we
.eq(1)
1418 sync
+= r1
.wb
.cyc
.eq(1)
1419 sync
+= r1
.wb
.stb
.eq(1)
1421 # OP_NONE and OP_BAD do nothing
1422 # OP_BAD & OP_STCX_FAIL were
1423 # handled above already
1424 with m
.Case(Op
.OP_NONE
):
1426 with m
.Case(Op
.OP_BAD
):
1428 with m
.Case(Op
.OP_STCX_FAIL
):
1431 with m
.Case(State
.RELOAD_WAIT_ACK
):
1432 ld_stbs_done
= Signal()
1433 # Requests are all sent if stb is 0
1434 comb
+= ld_stbs_done
.eq(~r1
.wb
.stb
)
1436 # If we are still sending requests, was one accepted?
1437 with m
.If((~bus
.stall
) & r1
.wb
.stb
):
1438 # That was the last word? We are done sending.
1439 # Clear stb and set ld_stbs_done so we can handle an
1440 # eventual last ack on the same cycle.
1441 # sigh - reconstruct wb adr with 3 extra 0s at front
1442 wb_adr
= Cat(Const(0, ROW_OFF_BITS
), r1
.wb
.adr
)
1443 with m
.If(is_last_row_addr(wb_adr
, r1
.end_row_ix
)):
1444 sync
+= r1
.wb
.stb
.eq(0)
1445 comb
+= ld_stbs_done
.eq(1)
1447 # Calculate the next row address in the current cache line
1448 row
= Signal(LINE_OFF_BITS
-ROW_OFF_BITS
)
1449 comb
+= row
.eq(r1
.wb
.adr
)
1450 sync
+= r1
.wb
.adr
[:LINE_OFF_BITS
-ROW_OFF_BITS
].eq(row
+1)
1452 # Incoming acks processing
1453 sync
+= r1
.forward_valid1
.eq(bus
.ack
)
1455 srow
= Signal(ROW_LINE_BITS
)
1456 comb
+= srow
.eq(r1
.store_row
)
1457 sync
+= r1
.rows_valid
[srow
].eq(1)
1459 # If this is the data we were looking for,
1460 # we can complete the request next cycle.
1461 # Compare the whole address in case the
1462 # request in r1.req is not the one that
1463 # started this refill.
1464 with m
.If(req
.valid
& r1
.req
.same_tag
&
1465 ((r1
.dcbz
& r1
.req
.dcbz
) |
1466 (~r1
.dcbz
& (r1
.req
.op
== Op
.OP_LOAD_MISS
))) &
1467 (r1
.store_row
== get_row(req
.real_addr
))):
1468 sync
+= r1
.full
.eq(0)
1469 sync
+= r1
.slow_valid
.eq(1)
1470 with m
.If(~r1
.mmu_req
):
1471 sync
+= r1
.ls_valid
.eq(1)
1473 sync
+= r1
.mmu_done
.eq(1)
1474 sync
+= r1
.forward_sel
.eq(~
0) # all 1s
1475 sync
+= r1
.use_forward1
.eq(1)
1477 # Check for completion
1478 with m
.If(ld_stbs_done
& is_last_row(r1
.store_row
,
1480 # Complete wishbone cycle
1481 sync
+= r1
.wb
.cyc
.eq(0)
1483 # Cache line is now valid
1484 cv
= Signal(INDEX_BITS
)
1485 comb
+= cv
.eq(cache_tags
[r1
.store_index
].valid
)
1486 comb
+= cv
.bit_select(r1
.store_way
, 1).eq(1)
1487 sync
+= cache_tags
[r1
.store_index
].valid
.eq(cv
)
1489 sync
+= r1
.state
.eq(State
.IDLE
)
1490 sync
+= Display("cache valid set %x "
1492 cv
, r1
.store_index
, r1
.store_way
)
1494 # Increment store row counter
1495 sync
+= r1
.store_row
.eq(next_row(r1
.store_row
))
1497 with m
.Case(State
.STORE_WAIT_ACK
):
1498 st_stbs_done
= Signal()
1500 adjust_acks
= Signal(3)
1502 comb
+= st_stbs_done
.eq(~r1
.wb
.stb
)
1503 comb
+= acks
.eq(r1
.acks_pending
)
1505 with m
.If(r1
.inc_acks
!= r1
.dec_acks
):
1506 with m
.If(r1
.inc_acks
):
1507 comb
+= adjust_acks
.eq(acks
+ 1)
1509 comb
+= adjust_acks
.eq(acks
- 1)
1511 comb
+= adjust_acks
.eq(acks
)
1513 sync
+= r1
.acks_pending
.eq(adjust_acks
)
1515 # Clear stb when slave accepted request
1516 with m
.If(~bus
.stall
):
1517 # See if there is another store waiting
1518 # to be done which is in the same real page.
1519 with m
.If(req
.valid
):
1520 _ra
= req
.real_addr
[ROW_LINE_BITS
:SET_SIZE_BITS
]
1521 sync
+= r1
.wb
.adr
[0:SET_SIZE_BITS
].eq(_ra
)
1522 sync
+= r1
.wb
.dat
.eq(req
.data
)
1523 sync
+= r1
.wb
.sel
.eq(req
.byte_sel
)
1525 with m
.If((adjust_acks
< 7) & req
.same_tag
&
1526 ((req
.op
== Op
.OP_STORE_MISS
)
1527 |
(req
.op
== Op
.OP_STORE_HIT
))):
1528 sync
+= r1
.wb
.stb
.eq(1)
1529 comb
+= st_stbs_done
.eq(0)
1531 with m
.If(req
.op
== Op
.OP_STORE_HIT
):
1532 sync
+= r1
.write_bram
.eq(1)
1533 sync
+= r1
.full
.eq(0)
1534 sync
+= r1
.slow_valid
.eq(1)
1536 # Store requests never come from the MMU
1537 sync
+= r1
.ls_valid
.eq(1)
1538 comb
+= st_stbs_done
.eq(0)
1539 sync
+= r1
.inc_acks
.eq(1)
1541 sync
+= r1
.wb
.stb
.eq(0)
1542 comb
+= st_stbs_done
.eq(1)
1544 # Got ack ? See if complete.
1546 with m
.If(st_stbs_done
& (adjust_acks
== 1)):
1547 sync
+= r1
.state
.eq(State
.IDLE
)
1548 sync
+= r1
.wb
.cyc
.eq(0)
1549 sync
+= r1
.wb
.stb
.eq(0)
1550 sync
+= r1
.dec_acks
.eq(1)
1552 with m
.Case(State
.NC_LOAD_WAIT_ACK
):
1553 # Clear stb when slave accepted request
1554 with m
.If(~bus
.stall
):
1555 sync
+= r1
.wb
.stb
.eq(0)
1557 # Got ack ? complete.
1559 sync
+= r1
.state
.eq(State
.IDLE
)
1560 sync
+= r1
.full
.eq(0)
1561 sync
+= r1
.slow_valid
.eq(1)
1563 with m
.If(~r1
.mmu_req
):
1564 sync
+= r1
.ls_valid
.eq(1)
1566 sync
+= r1
.mmu_done
.eq(1)
1568 sync
+= r1
.forward_sel
.eq(~
0) # all 1s
1569 sync
+= r1
.use_forward1
.eq(1)
1570 sync
+= r1
.wb
.cyc
.eq(0)
1571 sync
+= r1
.wb
.stb
.eq(0)
1573 def dcache_log(self
, m
, r1
, valid_ra
, tlb_hit
, stall_out
):
1576 d_out
, bus
, log_out
= self
.d_out
, self
.bus
, self
.log_out
1578 sync
+= log_out
.eq(Cat(r1
.state
[:3], valid_ra
, tlb_hit
.way
[:3],
1579 stall_out
, req_op
[:3], d_out
.valid
, d_out
.error
,
1580 r1
.wb
.cyc
, r1
.wb
.stb
, bus
.ack
, bus
.stall
,
1583 def elaborate(self
, platform
):
1589 # Storage. Hopefully "cache_rows" is a BRAM, the rest is LUTs
1590 cache_tags
= CacheTagArray()
1591 cache_tag_set
= Signal(TAG_RAM_WIDTH
)
1593 # TODO attribute ram_style : string;
1594 # TODO attribute ram_style of cache_tags : signal is "distributed";
1596 """note: these are passed to nmigen.hdl.Memory as "attributes".
1597 don't know how, just that they are.
1600 # TODO attribute ram_style of
1601 # dtlb_tags : signal is "distributed";
1602 # TODO attribute ram_style of
1603 # dtlb_ptes : signal is "distributed";
1605 r0
= RegStage0("r0")
1608 r1
= RegStage1("r1")
1610 reservation
= Reservation()
1612 # Async signals on incoming request
1613 req_index
= Signal(INDEX_BITS
)
1614 req_row
= Signal(ROW_BITS
)
1615 req_hit_way
= Signal(WAY_BITS
)
1616 req_tag
= Signal(TAG_BITS
)
1618 req_data
= Signal(64)
1619 req_same_tag
= Signal()
1622 early_req_row
= Signal(ROW_BITS
)
1624 cancel_store
= Signal()
1626 clear_rsrv
= Signal()
1631 use_forward1_next
= Signal()
1632 use_forward2_next
= Signal()
1634 cache_out_row
= Signal(WB_DATA_BITS
)
1636 plru_victim
= PLRUOut()
1637 replace_way
= Signal(WAY_BITS
)
1639 # Wishbone read/write/cache write formatting signals
1643 tlb_way
= TLBRecord("tlb_way")
1644 tlb_req_index
= Signal(TLB_SET_BITS
)
1645 tlb_hit
= TLBHit("tlb_hit")
1646 pte
= Signal(TLB_PTE_BITS
)
1647 ra
= Signal(REAL_ADDR_BITS
)
1649 perm_attr
= PermAttr("dc_perms")
1652 access_ok
= Signal()
1654 tlb_plru_victim
= TLBPLRUOut()
1656 # we don't yet handle collisions between loadstore1 requests
1658 comb
+= self
.m_out
.stall
.eq(0)
1660 # Hold off the request in r0 when r1 has an uncompleted request
1661 comb
+= r0_stall
.eq(r0_full
& (r1
.full | d_in
.hold
))
1662 comb
+= r0_valid
.eq(r0_full
& ~r1
.full
& ~d_in
.hold
)
1663 comb
+= self
.stall_out
.eq(r0_stall
)
1665 # deal with litex not doing wishbone pipeline mode
1666 # XXX in wrong way. FIFOs are needed in the SRAM test
1667 # so that stb/ack match up. same thing done in icache.py
1668 comb
+= self
.bus
.stall
.eq(self
.bus
.cyc
& ~self
.bus
.ack
)
1670 # Wire up wishbone request latch out of stage 1
1671 comb
+= self
.bus
.we
.eq(r1
.wb
.we
)
1672 comb
+= self
.bus
.adr
.eq(r1
.wb
.adr
)
1673 comb
+= self
.bus
.sel
.eq(r1
.wb
.sel
)
1674 comb
+= self
.bus
.stb
.eq(r1
.wb
.stb
)
1675 comb
+= self
.bus
.dat_w
.eq(r1
.wb
.dat
)
1676 comb
+= self
.bus
.cyc
.eq(r1
.wb
.cyc
)
1678 # call sub-functions putting everything together, using shared
1679 # signals established above
1680 self
.stage_0(m
, r0
, r1
, r0_full
)
1681 self
.tlb_read(m
, r0_stall
, tlb_way
, dtlb
)
1682 self
.tlb_search(m
, tlb_req_index
, r0
, r0_valid
,
1684 pte
, tlb_hit
, valid_ra
, perm_attr
, ra
)
1685 self
.tlb_update(m
, r0_valid
, r0
, dtlb
, tlb_req_index
,
1686 tlb_hit
, tlb_plru_victim
,
1688 self
.maybe_plrus(m
, r1
, plru_victim
)
1689 self
.maybe_tlb_plrus(m
, r1
, tlb_plru_victim
)
1690 self
.cache_tag_read(m
, r0_stall
, req_index
, cache_tag_set
, cache_tags
)
1691 self
.dcache_request(m
, r0
, ra
, req_index
, req_row
, req_tag
,
1692 r0_valid
, r1
, cache_tags
, replace_way
,
1693 use_forward1_next
, use_forward2_next
,
1694 req_hit_way
, plru_victim
, rc_ok
, perm_attr
,
1695 valid_ra
, perm_ok
, access_ok
, req_op
, req_go
,
1696 tlb_hit
, tlb_way
, cache_tag_set
,
1697 cancel_store
, req_same_tag
, r0_stall
, early_req_row
)
1698 self
.reservation_comb(m
, cancel_store
, set_rsrv
, clear_rsrv
,
1699 r0_valid
, r0
, reservation
)
1700 self
.reservation_reg(m
, r0_valid
, access_ok
, set_rsrv
, clear_rsrv
,
1702 self
.writeback_control(m
, r1
, cache_out_row
)
1703 self
.rams(m
, r1
, early_req_row
, cache_out_row
, replace_way
)
1704 self
.dcache_fast_hit(m
, req_op
, r0_valid
, r0
, r1
,
1705 req_hit_way
, req_index
, req_tag
, access_ok
,
1706 tlb_hit
, tlb_req_index
)
1707 self
.dcache_slow(m
, r1
, use_forward1_next
, use_forward2_next
,
1709 req_hit_way
, req_same_tag
,
1710 r0_valid
, req_op
, cache_tags
, req_go
, ra
)
1711 #self.dcache_log(m, r1, valid_ra, tlb_hit, stall_out)
1716 if __name__
== '__main__':
1718 vl
= rtlil
.convert(dut
, ports
=[])
1719 with
open("test_dcache.il", "w") as f
: