Ross Thompson
6ccbdc372d
Broken.
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Possible change to walker, dcache, tlb addressing.
Improves the naming of address signals.
But has a problem when the walker finishes the dcache does not get the correct
address on the cycle the DTLB is updated. This leads to incorrect index
selection in the dcache.
2021-07-19 10:33:27 -05:00
Ross Thompson
d0ed6e250a
Fixed LRSC in 64bit version. 32bit version is broken.
2021-07-17 20:58:49 -05:00
Ross Thompson
053e9593af
Before returning to the ready state the dcache must set SelAdr = 0 on the cycle before.
2021-07-17 18:26:29 -05:00
Ross Thompson
e9649eb1f5
Made furture progress in the mmu tests.
2021-07-16 15:56:06 -05:00
Ross Thompson
abce241f68
Also changed the shadow ram's dcache copy widths.
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Merge branch 'dcache' into main
2021-07-16 14:21:09 -05:00
Ross Thompson
d3715acf2d
Fixed walker fault interaction with dcache.
2021-07-16 12:22:13 -05:00
Ross Thompson
5ca7dc619c
Updated the ptw, lsuarb and dcache to hopefully solve the interlock issues.
2021-07-16 11:12:57 -05:00
Kip Macsai-Goren
ba5bb12e26
Still broken, midway through fixing understanding of how ptw and datacache interact in time especially wrt adrE, adrM, faults, and tlb interaction.
2021-07-15 18:30:29 -04:00
Ross Thompson
c39a228266
Fixed how the dcache and page table walker stall cpu so that once a tlb miss occurs the CPU is always stalled until the walk is complete, the tlb updated, and the dcache fetched and hits.
2021-07-15 11:00:42 -05:00
Ross Thompson
c954fb510b
Renamed DCacheStall to LSUStall in hart and hazard.
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Added missing logic in lsu.
2021-07-15 10:16:16 -05:00
Ross Thompson
f234875779
dcache STATE_CPU_BUSY needs to assert CommittedM. This is required to ensure a completed memory operation is not bound to an interrupt. ie. MEPC should not be PCM when committed.
2021-07-14 23:08:07 -05:00
Ross Thompson
6163629204
Finally have the ptw correctly walking through the dcache to update the itlb.
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Still not working fully.
2021-07-14 22:26:07 -05:00
Ross Thompson
d41c9d5ad9
Added d cache StallW checks for any time the cache wants to go to STATE_READY.
2021-07-14 17:25:50 -05:00
Ross Thompson
d3a1a2c90a
Fixed d cache not honoring StallW for uncache writes and reads.
2021-07-14 17:23:28 -05:00
Ross Thompson
1d7aa27316
Fixed a bug where the dcache did not update the read data if the CPU was stalled, but the memory not stalled.
2021-07-14 15:47:38 -05:00
Ross Thompson
e17de4eb11
Separated interruptM into PendingInterruptM and InterruptM. The d cache now takes in both exceptions and PendingInterrupts.
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This solves the committedM issue.
2021-07-14 15:00:33 -05:00
Ross Thompson
ef598d0e79
Implemented uncached reads.
2021-07-13 23:03:09 -05:00
Ross Thompson
b6e5670bc3
Added CommitedM to data cache output.
2021-07-13 22:43:42 -05:00
Ross Thompson
278bbfbe3c
Partially working changes to support uncached memory access. Not sure what CommitedM is.
2021-07-13 17:24:59 -05:00
Ross Thompson
b780e471b4
Fixed interaction between icache stall and dcache. On hit dcache needs to enter a cpu busy state when the cpu is stalled.
2021-07-13 14:51:42 -05:00
Ross Thompson
51249a0e04
Fixed the fetch buffer accidental overwrite on eviction.
2021-07-13 14:21:29 -05:00
Ross Thompson
2034a6584f
Dcache AHB address generation was wrong. Needed to zero the offset.
2021-07-13 14:19:04 -05:00
Ross Thompson
ee09fa5f58
Moved StoreStall into the hazard unit instead of in the d cache.
2021-07-13 13:20:50 -05:00
Ross Thompson
2004b2e044
Fixed back to back store issue.
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Note there is a bug in the lsuarb which needs to arbitrate a few execution stage signals.
2021-07-13 12:46:20 -05:00
Ross Thompson
40922cf064
Fixed subword write. subword read should not feed into subword write.
2021-07-13 11:21:44 -05:00
Ross Thompson
9fe6190763
Team work on solving the dcache data inconsistency problem.
2021-07-12 23:46:32 -05:00
Ross Thompson
8ca8b9075d
Progress towards the test bench flush.
2021-07-12 14:22:13 -05:00
Ross Thompson
282bde7205
Fixed the spurious AHB requests to address 0. Somehow by not having a default
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(else) in the fsm branch selection for STATE_READY in the d cache it was
possible to take an invalid branch through the fsm.
2021-07-10 22:34:47 -05:00
Ross Thompson
d9fa3af94d
Loads are working.
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There is a bug when the icache stalls 1 cycle before the d cache.
2021-07-10 22:15:44 -05:00
Ross Thompson
a82c4c99c2
Actually writes the correct data now on stores.
2021-07-10 17:48:47 -05:00
Ross Thompson
ee72178eec
Write miss with eviction works.
2021-07-10 15:17:40 -05:00
Ross Thompson
0a6c86af94
Write Hits and Write Misses without eviction are working correctly! The next
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step is to add eviction of dirty lines.
2021-07-10 10:56:25 -05:00
Ross Thompson
94b29ec418
Loads in modelsim, but the first store double does not function correctly. The write address is wrong so the cache is updated using the wrong address.
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I think this is do to the cycle latency of stores. We probably need extra muxes to select between MemPAdrM and MemPAdrW depending on if the write is a
full cache block or a word write from the CPU.
2021-07-09 17:14:54 -05:00
Ross Thompson
7e98610651
Design loads in modelsim, but trap is an X.
2021-07-09 15:37:16 -05:00
Ross Thompson
6abd23a61d
Lint passes, but I only hope to have loads working. Stores, lr/sc, atomic, are not fully implemented.
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Also faults and the dcache ptw interlock are not implemented.
2021-07-09 15:16:38 -05:00
Ross Thompson
6041aef263
completed read miss branch through dcache fsm.
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The challenge now is to connect to ahb and lsu.
2021-07-08 17:53:08 -05:00
Ross Thompson
4c5aee3042
This d cache fsm is getting complex.
2021-07-08 15:26:16 -05:00
Ross Thompson
adcc7afffa
Partial implementation of the data cache. Missing the fsm.
2021-07-07 17:52:16 -05:00
David Harris
d2e3e14cbc
Merge branch 'main' of https://github.com/davidharrishmc/riscv-wally into main
2021-07-04 18:55:24 -04:00
David Harris
57e1111df3
Gave names to for loops in generate blocks for ease of reference
2021-07-04 18:52:16 -04:00
bbracker
11606e96f1
ICacheCntrl now reacts differently to InstrPageFaultF vs ITLBWriteF
2021-07-04 18:17:06 -04:00
Ben Bracker
66692af57c
src/cache/ICacheCntrl.sv
2021-07-03 11:24:41 -05:00
Ben Bracker
d6c7dc02ed
fix ICache indenting
2021-07-03 11:11:07 -05:00
Ross Thompson
386193de00
added page table walker fault exit for icache.
2021-07-01 17:59:55 -05:00
Ross Thompson
3dae02818c
OMG. It's working!
2021-07-01 17:37:53 -05:00
Ross Thompson
4530e43df6
The icache ptw interlock is actually correct now. There needed to be a 1 cycle delay.
2021-06-30 17:02:36 -05:00
Ross Thompson
2598f08782
Page table walker now walks the table.
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Added interlock so the icache stalls.
Page table walker not walking correctly, goes to fault state.
2021-06-29 22:33:57 -05:00
Ross Thompson
d5063bee7d
Updated icache to abhlite to use pa_bits length and moved F/D stage instr register to ifu from icache.
2021-06-23 15:13:56 -05:00
Ross Thompson
03084a4128
Icache now uses physical lenght bits rather than XLEN.
2021-06-21 16:41:09 -05:00
Ross Thompson
8ec5b0c4f1
Improved some names in icache.
2021-06-21 16:40:37 -05:00
