Ross Thompson
857f59ab5c
Now have global history working correctly.
2021-06-01 10:57:43 -05:00
Ross Thompson
f6c88666cf
may have fixed the global branch history predictor.
...
The solution required a completed rewrite and understanding of how the GHR needs to be speculatively updated and repaired.
2021-05-31 16:11:12 -05:00
bbracker
39ae743543
turns out I should not have tried renaming FStallD to FPUStallD because that name was already used! All the same it does feel weird to have two such signals floating around \(ah pun!\)
2021-05-28 23:11:37 -04:00
Ross Thompson
8a035104ac
It's a bit sloppy, but the global history predictor is working correctly now.
...
There were two major bugs with the predictor.
First the update mechanism was completely wrong. The PHT is updated with the GHR that was used to lookup the prediction. PHT[GHR] = Sat2(PHT[GHR], branch outcome).
Second the GHR needs to be updated speculatively as the branch is predicted. This is important so that back to back branches' GHRs are not the same. The must be different to avoid aliasing. Speculation of the GHR update allows them to be different. On mis prediction the GHR must be reverted.
This implementation is a bit sloppy with names and now the GHR recovery is performed. Updates to follow.
2021-05-27 23:06:28 -05:00
Ross Thompson
fec40a1b75
fixed bug with icache miss spill fsm branch.
2021-05-25 14:26:22 -05:00
Ross Thompson
16e037b8e9
Fixed bug in the two bit sat counter branch predictor. The SRAM needs to be read enabled by StallF.
2021-05-24 23:24:54 -05:00
Ross Thompson
65632cb7c9
Fixed minor bug in instruction class decoding.
2021-05-24 13:41:14 -05:00
Ross Thompson
72f77656a3
Fixed bug with instruction classification. The class decoder was incorretly labeling jalr acting as both jalr and jr (no link).
2021-05-24 12:37:16 -05:00
Ross Thompson
21acc45121
Fixed synthesis bug with icache valid bit.
2021-05-04 13:03:08 -05:00
Ross Thompson
52e4c49bbb
Fixed icache pcmux control for handling miss spill miss.
2021-05-04 11:05:01 -05:00
Ross Thompson
7f38056879
fixed subtle typo in icache fsm. Was messing up hit spill hit.
...
I believe the mibench qsort benchmark runs after this icache fix.
2021-05-03 16:55:36 -05:00
Ross Thompson
cdb602c9ce
Removed combinational loops between icache and PMA checker.
2021-05-03 14:51:25 -05:00
Ross Thompson
19a93345b5
Reduced icache to 1 port memory.
2021-05-03 14:47:49 -05:00
Ross Thompson
a54c231489
Eliminated extra register and fixed ports to icache.
...
Still need to support physical tag check and write in icache memory.
Still need to reduce to 1 port SRAM in icache.
I would like to refactor the icache code.
2021-05-03 12:04:54 -05:00
Ross Thompson
c0a4b7cb17
Fixed typo in ifu for bypassing branch predictor.
...
Fixed missing signal name in local history predictor.
2021-05-03 08:56:45 -05:00
Jarred Allen
8fd9cc679b
Fix compile error in branch predictor
2021-04-29 14:36:56 -04:00
Shreya Sanghai
1e57c6bb92
fixed bug in gshare, global and local history BP
2021-04-29 06:14:32 -04:00
Ross Thompson
72363f5c66
Added the ability to exclude branch predictor.
2021-04-26 14:27:42 -05:00
Ross Thompson
afbb100860
Fixed issue with not saving the first cache block read on a miss spill.
2021-04-26 12:57:34 -05:00
bbracker
31a0387136
merge cleanup; mem init is broken
2021-04-26 08:00:17 -04:00
bbracker
ba94fa3436
it says I need to merge in order to pull
2021-04-26 07:46:24 -04:00
bbracker
1cc0dcc83f
progress on bus and lrsc
2021-04-26 07:43:16 -04:00
Ross Thompson
6e803b724e
Merge branch 'tests' into icache-almost-working
2021-04-25 21:25:36 -05:00
Ross Thompson
020fb65adf
Fixed icache for 32 bit.
...
Merge branch 'cache' into main
2021-04-22 16:45:29 -05:00
Ross Thompson
d8ab7a5de2
Partially working icache.
...
The current issue is a StallF is required to halt the icache from getting an updated PCF. However
if the dmemory is the reason for a stall it is possible for the icache stall to hold the d memory request continuously causing d memory to repeatedly read from memory. This keeps StallF high and
the icache FSM is never allowed to complete.
2021-04-22 10:20:36 -05:00
Thomas Fleming
e336fbd108
Merge branch 'main' of github.com:davidharrishmc/riscv-wally into main
...
Conflicts:
wally-pipelined/src/ifu/ifu.sv
2021-04-21 20:01:08 -04:00
Thomas Fleming
4bae666fa1
Implement virtual memory protection
2021-04-21 19:58:36 -04:00
Ross Thompson
7b3735fc25
Fixed for the instruction spills.
2021-04-21 16:47:05 -05:00
Teo Ene
ddc98e7d08
Fixed most relevant remaining synthesis compilation warnings with Ben
2021-04-21 16:06:27 -05:00
Ross Thompson
532c8771ba
major progress.
...
It's running the icache is imperas tests now.
Compressed does not work yet.
2021-04-21 08:39:54 -05:00
Ross Thompson
f3093ac612
Why was the linter messed up?
...
There are a number of combo loops which need fixing outside the icache. They may be fixed in main.
We get to instruction address 50 now!
2021-04-20 22:06:12 -05:00
Ross Thompson
99424fb983
Progress on icache. Fixed some issues aligning the PC with instruction. Still broken.
2021-04-20 21:19:53 -05:00
Ross Thompson
251ece20fe
Broken icache. Design is done. Time to debug.
2021-04-20 19:55:49 -05:00
Jarred Allen
850f728cc7
Merge branch 'main' into cache
2021-04-19 00:05:23 -04:00
Thomas Fleming
ff9f1e5e72
Connect tlb and icache properly
2021-04-15 14:48:39 -04:00
Jarred Allen
81c02bda55
Merge branch 'main' into cache
2021-04-15 13:47:19 -04:00
Shreya Sanghai
0369fc5d1e
Cherry Pick merge of Shreya's localhistory predictor changes into main.
...
fixed minor bugs in localHistory
2021-04-15 09:04:36 -05:00
ShreyaSanghai
6d4042e479
added localHistoryPredictor
2021-04-15 08:58:22 -05:00
Shreya Sanghai
7e9a0602ea
fixed bugs in global history to read latest GHRE
...
Cherry pick Shreya's commits into main branch.
2021-04-15 08:55:22 -05:00
Jarred Allen
3717699ad9
Add a comment to explain a detail
2021-04-14 23:14:59 -04:00
Jarred Allen
892dfd5a9b
More icache bugfixes
2021-04-14 19:03:33 -04:00
Teo Ene
1018a10625
Various code syntax changes to bring HDL to a synthesizable level
2021-04-13 11:27:12 -05:00
Jarred Allen
fc8b8ad7aa
A few more cache fixes
2021-04-13 01:07:40 -04:00
Jarred Allen
d99b8f772e
Merge from branch 'main'
2021-04-08 17:19:34 -04:00
Thomas Fleming
303c2c4839
Implement support for superpages
2021-04-08 02:44:59 -04:00
Ross Thompson
c91436d3b7
Merge branch 'icache_bp_bug' into tests
...
Not sure this merge is right.
2021-04-06 21:46:40 -05:00
Ross Thompson
98a04abe6c
Merge remote-tracking branch 'refs/remotes/origin/tests' into tests
2021-04-06 21:20:55 -05:00
Jarred Allen
bd8f1eea3c
Fix another bug in icache
2021-04-06 17:47:00 -04:00
Jarred Allen
3afc358974
Fix another bug in icache
2021-04-06 12:48:42 -04:00
Jarred Allen
c95da7d11e
Fix bug in icache
2021-04-03 18:10:54 -04:00
Thomas Fleming
fdb20ee1cf
Implement sfence.vma and fix tlb writing
2021-04-01 15:55:05 -04:00
Shreya Sanghai
df149d1be7
fixed minor bugs in localHistory
2021-04-01 13:40:08 -04:00
ShreyaSanghai
28a9c6ba56
added localHistoryPredictor
2021-04-01 22:22:40 +05:30
Shreya Sanghai
b544526766
fixed bugs in global history to read latest GHRE
2021-03-31 21:56:14 -04:00
Ross Thompson
9172e52286
Corrected a number of bugs in the branch predictor.
...
Added performance counters to individually track
branches; jumps, jump register, jal, and jalr; return.
jump and jump register are special cases of jal and jalr.
Similarlly return is a special case of jalr.
Also added counters to track if the branch direction was wrong,
btb target wrong, or the ras target was wrong.
Finally added one more counter to track if the BP incorrectly predicts
a non-cfi instruction.
2021-03-31 11:54:02 -05:00
Ross Thompson
a64a37d702
Merge of main with the new icache and the branch predictor. I believe there is a bug in the icache with unaligned memory access. The second part of the access is incorrectly relying on the PCF being the address of the next two bytes of the instruction. However this is not always the case as the branch predictor can get the wrong target address. The icache needs to generate the +2 address internally.
2021-03-30 23:18:20 -05:00
Thomas Fleming
eca2427f94
Merge remote-tracking branch 'origin/main' into main
...
Bring icache and MMU code together
Conflicts:
wally-pipelined/src/ifu/ifu.sv
wally-pipelined/testbench/testbench-imperas.sv
2021-03-30 22:24:47 -04:00
Thomas Fleming
7126ab7864
Complete basic page table walker
2021-03-30 22:19:27 -04:00
ushakya22
6b9ae41302
Merge branch 'main' of https://github.com/davidharrishmc/riscv-wally into main
2021-03-30 15:25:07 -04:00
Ross Thompson
2a308309e4
fixed some bugs with the RAS.
2021-03-30 13:57:40 -05:00
Jarred Allen
631454ccf9
Merge branch 'cache2' into cache
...
Conflicts:
wally-pipelined/testbench/testbench-imperas.sv
2021-03-30 13:32:33 -04:00
Jarred Allen
7ca57cc4fc
Merge branch 'main' into cache
...
Conflicts:
wally-pipelined/regression/wave-dos/ahb-waves.do
wally-pipelined/src/ifu/ifu.sv
wally-pipelined/testbench/testbench-busybear.sv
wally-pipelined/testbench/testbench-imperas.sv
2021-03-30 12:55:01 -04:00
Jarred Allen
39bf2347bc
Fix error when reading an instruction that crosses a line boundary
2021-03-25 18:47:23 -04:00
ShreyaSanghai
139c2076a1
Removed PCW and InstrW from ifu
2021-03-26 01:53:19 +05:30
Jarred Allen
32829bf7a1
Remove old icache
2021-03-25 15:46:35 -04:00
Jarred Allen
5f4feb0ff1
Works for misaligned instructions not on line boundaries
2021-03-25 15:42:17 -04:00
Jarred Allen
3b4f0141f4
Begin work on compressed instructions
2021-03-25 14:43:10 -04:00
Jarred Allen
0290568a52
Make cache output NOP after a reset
2021-03-25 13:18:30 -04:00
Jarred Allen
602271ff7b
rv64i linear control flow now working
2021-03-25 13:02:26 -04:00
Jarred Allen
ba95557c44
More progress on icache controller
2021-03-25 13:01:11 -04:00
Jarred Allen
ad0d77e9e1
Begin rewrite of icache module to use a direct-mapped scheme
2021-03-25 13:01:10 -04:00
Jarred Allen
b774d35c34
Output NOP instead of BAD when reset
2021-03-25 12:42:48 -04:00
bbracker
02e924e55a
instrfaults not respecting stalls bugfix
2021-03-25 00:16:26 -04:00
Ross Thompson
1c6e37120e
Fixed RAS errors. Still some room for improvement with the BTB and RAS.
2021-03-23 23:00:44 -05:00
Jarred Allen
4410944049
Merge branch 'main' into cache
2021-03-23 23:35:36 -04:00
Ross Thompson
84ad1353e4
Fixed a bunch of bugs with the RAS.
2021-03-23 21:49:16 -05:00
Ross Thompson
4fb7a1e0a6
Fixed the valid bit issue. Now the branch predictor is actually predicting instructions.
2021-03-23 20:20:23 -05:00
Ross Thompson
49348d734b
fixed issue with BTB's valid bit not updating. There is still a problem is valid not ocurring in the correct clock cycle.
2021-03-23 20:06:45 -05:00
Ross Thompson
95dbc5f1fa
fixed a whole bunch of bugs with the branch predictor. Still an issue with how PCNextF is not updated because the CPU is stalled.
2021-03-23 16:53:48 -05:00
Shreya Sanghai
1d6a2989ed
PC counts branch instructions
2021-03-23 14:25:51 -04:00
Jarred Allen
0f8fe8fb3b
Document some internal signals
2021-03-23 00:10:35 -04:00
Jarred Allen
6ffa01cc4d
Add comments explaining icache inputs
2021-03-23 00:07:39 -04:00
Jarred Allen
827993598d
Small commit to see if new hook tests non-main branch
2021-03-22 23:57:01 -04:00
Jarred Allen
6ce52f9b80
Remove DelaySideD since it isn't needed
2021-03-22 15:13:23 -04:00
Jarred Allen
b871bfe714
Update icache interface
2021-03-22 15:04:46 -04:00
Jarred Allen
f9cf05a7d4
Fix bug with PC incrementing
2021-03-20 18:06:03 -04:00
Jarred Allen
a2bf5ac202
Fix another bug in the icache (why so many of them?)
2021-03-20 17:54:40 -04:00
Jarred Allen
c5f99c4a34
Revert "Change flop to listen to StallF"
...
This reverts commit c8028710a5
.
2021-03-20 17:34:19 -04:00
Jarred Allen
c8028710a5
Change flop to listen to StallF
2021-03-20 17:04:13 -04:00
Jarred Allen
279c09b27c
Merge changes from main
2021-03-18 18:58:10 -04:00
Shreya Sanghai
bbe0957df5
Merge branch 'gshare' into main
...
Conflicts:
wally-pipelined/regression/wave.do
2021-03-18 17:25:48 -04:00
Ross Thompson
1091dd10c1
Switched to gshare from global history.
...
Fixed a few minor bugs.
2021-03-18 16:05:59 -05:00
Ross Thompson
8f4051543c
Fixed minor bug with the size of gshare.
2021-03-18 16:00:09 -05:00
Shreya Sanghai
eb86bfc084
removed unnecesary PC registers in ifu
2021-03-18 16:31:21 -04:00
Thomas Fleming
7f7597e667
Connect tlb, pagetablewalker, and memory
2021-03-18 14:35:46 -04:00
Shreya Sanghai
36f0631203
added gshare and global history predictor
2021-03-16 17:03:01 -04:00
Jarred Allen
a82aa23399
Fix icache for jumping into misaligned instructions
2021-03-16 16:57:51 -04:00
Shreya Sanghai
9eed875886
added global history branch predictor
2021-03-16 16:06:40 -04:00
Jarred Allen
ac9fd5a323
Fix BEQZ tests
2021-03-14 15:42:27 -04:00
Jarred Allen
926235b180
Merge upstream changes
2021-03-14 14:57:53 -04:00