Luke Wren
185194973f
Add a custom instruction (bextm/bextmi: 1 to 8-bit version of bext/bexti from Zbs) for fooling around with toolchains
2022-08-06 23:02:08 +01:00
Luke Wren
797bff81ab
DM: fix any/allnonexistent going low when hasel is set. The hart array mask is in addition to the hart selected by hartsel.
2022-07-30 19:55:22 +01:00
Luke Wren
9787c604ad
Add missing ebreaku field to dcsr (U-mode counterpart to ebreakm)
2022-07-30 17:31:53 +01:00
Luke Wren
0567c2c9fe
Two minor DM bugs:
...
- Writes to dmcontrol.resumereq should be ignored if dmcontrol.haltreq is also set
- aarsize and regno should be ignored when command.transfer is not set
2022-07-30 17:22:46 +01:00
Luke Wren
add19506a5
Oops, bad if block nesting in PMP
2022-07-25 13:09:03 +01:00
Luke Wren
b7d9defcf2
Add MUL_FASTER option to retire fast mul to stage 2 instead of stage 3
2022-07-05 03:37:19 +01:00
Luke Wren
254350d300
Clean up tie-off of hardwired PMP registers
2022-07-04 14:31:42 +01:00
Luke Wren
6e80492723
Typo
2022-07-04 12:09:21 +01:00
Luke Wren
cac98568e6
Ignore read data from failed SBA accesses
2022-07-03 20:58:01 +01:00
Luke Wren
c7a32c4d00
SBA: fix alignment check using a stale address when the trigger is an sbaddress write. Fix new transfers being allowed to start when sberror or sbbusyerror are set.
2022-07-03 19:02:30 +01:00
Luke Wren
ae11d04b10
Add HMASTER output to processor wrappers, to indicate when the bus cycle is driven by SBA rather than the core
2022-07-03 18:02:47 +01:00
Luke Wren
b1225c386c
Add missing 1port SBA change, and update example soc and bus compliance tb to reflect
2022-07-03 17:57:03 +01:00
Luke Wren
9e15cd3485
Add standalone SBA-to-AHB shim, and make SBA off by default in the DM
2022-07-03 15:30:33 +01:00
Luke Wren
d5cd3e0681
Add SBA patch-through to 1-core wrapper.
...
Add SBA properties to bus compliance checks.
Hook up SBA in dual-core single-port debug tb.
2022-07-03 15:17:44 +01:00
Luke Wren
d6bef56788
Fix missing byte picking/replication in non-word-aligned SBA transfers
2022-07-03 14:22:12 +01:00
Luke Wren
51bc26f8ac
First pass at adding system bus access to DM. Currently only the 2-port processor supports SBA patchthrough.
2022-07-03 00:25:47 +01:00
Luke Wren
36cee73d1f
Fix acmd FSM not selecting the correct hart signal for its state transitions, and make flush take precedence over debug injection in frontend. (Changes from aborted abstract access memory implementation, see abstract-access-memory branch)
2022-07-02 22:46:20 +01:00
Luke Wren
edfe7f601e
Clear local monitor on non-debug trap entry/exit
2022-06-26 21:55:51 +01:00
Luke Wren
c2756e79fc
Fix misreading of spec: hartsel hart is selected in addition to those bits set in hart array mask, when hasel is set.
2022-06-26 19:58:01 +01:00
Luke Wren
fb15894731
Hopefully fix case where we jump to the address immediately after a
...
halfword-sized word-aligned predicted-taken branch, and an
address-phase hold causes the jump target to go to the fetch address
counter, causing a spurious BTB match on the branch.
2022-06-26 15:28:08 +01:00
Luke Wren
33cec49952
Fix bad predbranch tracking on a jump to a predicted-taken non-taken
...
branch which is halfword-sized and halfword-aligned, causing CIR
and PC to diverge.
2022-06-26 15:26:04 +01:00
Luke Wren
5455349961
Add menvcfg CSR, and comment explaining why we don't have mseccfg CSR
2022-06-26 01:25:48 +01:00
Luke Wren
ad8f883406
First pass at hart array mask register in DM
2022-06-25 20:34:53 +01:00
Luke Wren
5193dfe477
Add separate define HAZARD3_ASSERTIONS for enabling internal assertions,
...
and enable it only on the bus compliance model checks. Trying to make
the solver's life easier in instruction_fetch_match.
2022-06-25 20:08:40 +01:00
Luke Wren
173f5dba9d
Fix jump target being unstable during a CIR-locked branch-to-self on a partial predicted branch match, due to the addr_is_regoffs decode not being tied off.
2022-06-25 20:07:43 +01:00
Luke Wren
8ef9d77be8
Add 'everything but MHARTID' option to config_inst, to allow its reuse in multicore instantiations.
...
Use this to fix the multicore tb not instantiating cores with all parameters correct (e.g. U_MODE)
2022-06-25 13:11:40 +01:00
Luke Wren
31efd07042
Fix incorrect tracking of predictedness of fetch data phase. Fixes performance regression in RV32IMC CoreMark (now runs faster, as it should.)
2022-06-25 11:32:56 +01:00
Luke Wren
979e80be99
Attempt to fix fetch mismatch caused by jumping halfway into a 32-bit
...
instruction that precedes a taken branch.
The bookkeeping in the frontend has been tightened up so that the entire
branch instruction, and nothing but the branch instruction, is marked as a
taken branch. This required some extra state, e.g. remembering the size of
the taken branch instruction, but saved an incrementer on the BTB source
address value.
2022-06-24 19:58:21 +01:00
Luke Wren
d9389fb23e
Fix a half-valid valid address phase being left behind when taking a new path with the jump going straight to the bus. If left in place, this causes the next-next fetch to be marked as half valid, corrupting fetch data.
2022-06-16 01:42:28 +01:00
Luke Wren
f8aad6d2f3
Fix some bugs, too tired to list them, look at the diff
2022-06-15 04:05:31 +01:00
Luke Wren
0766ec6f8a
First pass at adding branch prediction
2022-06-15 02:05:46 +01:00
Luke Wren
3703b1fc4c
Allow use of cir_flush_behind in frontend_match formal tb
2022-06-13 20:36:15 +01:00
Luke Wren
e68d8a6cd6
Fix two frontend bugs: possibility for fetch to be blocked at CIR whilst also not going to FIFO (fixed by making those signals the complement of each other) and typo in the shift value for shifting into a CIR with 32 bits of contents, which is only reachable via a CIR-locked branch to an unaligned address.
2022-06-13 01:23:32 +01:00
Luke Wren
26d54d0023
Re-rewrite frontend to track the halfword-validity of in-flight transfers, and clean up the old cir_lock mechanism to be a modified flush
2022-06-12 21:01:39 +01:00
Luke Wren
e3da922f8b
Revert previous frontend changes. Seemed promising but is a dead end for area.
...
The original frontend design can probably be tweaked to support predictions.
2022-06-12 16:25:42 +01:00
Luke Wren
940b7e4009
Actually still need 7 halfwords for full throughput in the case of sequential word-sized halfword-aligned instructions
2022-06-12 16:21:56 +01:00
Luke Wren
8458dff083
Fix bus errors not being applied in frontend
2022-06-12 05:28:21 +01:00
Luke Wren
23b4dbe7f3
Redesign fetch queue: 2x32 + 3x16 -> 6x16.
...
Should make it easier to support finer-grained flushing,
and handle predicted branches cleanly.
2022-06-12 02:44:08 +01:00
Luke Wren
d5a202e4a5
Add standalone frontend formal tb
2022-06-11 20:14:24 +01:00
Luke Wren
3b5879da66
Small code cleanup in frontend. The address phase alignment state no longer needs to be tracked, since we just generate word accesses always, for simplicity.
2022-06-11 14:27:59 +01:00
Luke Wren
de9b51b787
Remove default zeroing of fetch address when no fetch is asserted -- this puts LUTs on a critical path and arguably causes more toggling than asserting the sequentially next address by default.
2022-06-11 14:26:40 +01:00
Luke Wren
11596a5bd7
Remove unused/untested RISC-V timer implementation
2022-06-09 00:12:26 +01:00
Luke Wren
ea2b8888a4
Update copyright years
2022-06-09 00:12:01 +01:00
Luke Wren
ae2784d0ea
PMP config: separate granularity config from hardwired region config. Give correct read value for G > 1.
2022-06-03 17:09:43 +01:00
Luke Wren
e0a9fb7312
Add option to hardwire PMP regions, or reduce their granularity
2022-06-03 01:19:03 +01:00
Luke Wren
66965ac073
Fix inverted sc return code (argh) and lr/sc tests which also assumed the sc code was inverted
2022-05-28 15:36:21 +01:00
Luke Wren
81aec325bb
ecall from U-mode has a different mcause value than ecall from M-mode
2022-05-28 12:07:29 +01:00
Luke Wren
f2876eb51f
Fix bad mepc reported after branching to a branch in a no-X address range
2022-05-27 22:47:04 +01:00
Luke Wren
0e462574b2
Move declaration of x_exec_pmp_fail to before its first use
2022-05-27 15:04:43 +01:00
Luke Wren
156fbcd019
Update behaviour of mstatus.mpp and mprv on mret to match priv-1.12 spec
2022-05-26 00:42:50 +01:00
Luke Wren
a17b941e38
Add U bit to misa, and fix some broken debug tests (no hazard3 bugs)
2022-05-25 23:46:23 +01:00
Luke Wren
0efcf53fe5
Fix X PMP fail not suppressing load/store address phase.
...
Fix PMP-failed load/store still passing on a data phase tag to stage 3.
Fix WFI still pausing the core after a PMP X fail.
2022-05-25 16:18:03 +01:00
Luke Wren
e2b9a3b2f9
Fix two PMP-related bugs:
...
1. Generating PMP load/store exceptions when the instruction is not a load/store
2. Passing a PMP exec permission exception into M whilst the frontend is still
starved, causing early taking of the exception and a bad mepc value.
2022-05-25 13:23:44 +01:00
Luke Wren
51750eb81d
Add mstatus.tw to control U-mode WFI, and prevent mret execution in U-mode.
2022-05-24 21:12:44 +01:00
Luke Wren
c93228d13e
Integrate PMP, and fix a couple of PMP bugs
2022-05-24 19:57:45 +01:00
Luke Wren
4878a752d6
Plumb privilege state through to the bus ports
2022-05-24 18:24:34 +01:00
Luke Wren
f033cde874
Add test for readability of CSRs in U mode. Fix readback value of mstatus.mpp
2022-05-24 17:30:24 +01:00
Luke Wren
0199f48087
Add read-only counter CSRs to readability/writability tests, and fix cycleh being unreadable when U mode is not implemented
2022-05-24 16:44:03 +01:00
Luke Wren
d62861159f
First pass at U-mode CSR support. Bizarrely causes CXXRTL tb to not write to stdout when invoked by subprocess.run from Python.
2022-05-24 16:17:54 +01:00
Luke Wren
2df1179994
Wire privilege through from core to bus masters. Tied off inside core.
2022-05-24 14:05:26 +01:00
Luke Wren
c0b5d73cbd
Typo in for loop, surprised Yosys accepted this
2022-05-23 18:15:36 +01:00
Luke Wren
5466c8131e
Sketch in PMP implementation
2022-05-23 18:06:23 +01:00
Luke Wren
06647b78c6
Fix IALIGN fault to trap on the control flow instruction instead of its target
2022-05-23 16:25:43 +01:00
Luke Wren
da244f54c3
Remove unused FAKE_DUALPORT option from regfile
2022-05-23 16:22:01 +01:00
Luke Wren
f849517202
Split CSR addresses into separate header file
2022-05-23 15:54:37 +01:00
Luke Wren
5f4127948d
Add a parameter to control register file reset, instead of the weird ifdef tree
2022-05-23 13:29:44 +01:00
Luke Wren
df0fd536eb
Fix IRQ priority to match the priv spec
2022-05-23 12:56:37 +01:00
Luke Wren
96a9ee18e1
Add IALIGN exception to non-RVC implementations
2022-05-23 12:47:48 +01:00
Luke Wren
c4e81922da
Don't store bit 1 of mepc on non-RVC implementations
2022-05-23 12:27:07 +01:00
Luke Wren
210dbeae64
Correct the name and operation of the brev8 (formerly rev.b) instruction
2022-05-20 15:28:18 +01:00
Luke Wren
a2582976fc
Fix opcodes for zip/unzip, which are wrong in the bitmanip copy of the Zbkb spec, but correct in the crypto copy of that spec
2022-05-20 15:15:37 +01:00
Luke Wren
43e0b1d16a
Implement Zbkb (untested)
2022-05-06 17:36:25 +01:00
Luke Wren
2c8f3974d0
Correctly implement fence.i as branch-to-next. Make Zifencei optional. Tighten up decode on fence and fence.i.
2022-04-09 13:49:16 +01:00
Luke Wren
35651f52a7
Stronger property for correct predecode
2022-04-05 08:18:00 +01:00
Luke Wren
20cf408632
Add fine (as well as coarse) register predecode, so that predecoded regnum can be used in bypass zeroing.
2022-04-04 20:16:19 +01:00
Luke Wren
357efac66e
Don't decode unnecessary bits in register predecode logic
2022-04-04 18:22:09 +01:00
Luke Wren
be80bd4c18
Radical opinion, we should have good performance by default, not bad
2022-04-02 17:53:22 +01:00
Luke Wren
7dc5046505
Perf option for dedicated branch comparator
2022-04-02 11:40:47 +01:00
Luke Wren
3c61fae9ef
Remove the halfword fetch thing, was only really useful on RISCBoy
2022-04-02 10:54:16 +01:00
Luke Wren
7b8fe43c1c
Fix bad timing of predecoded regnum register update (thanks BMC)
2022-04-02 10:11:55 +01:00
Luke Wren
b80b09afe5
Typo -- fully encode all 128 possible IRQs
2022-03-15 09:01:55 +00:00
Luke Wren
b0b8703ea4
Support up to 128 IRQs
2022-03-13 09:27:43 +00:00
Luke Wren
887c93dbf0
Reuse predecoded regnums for bypass mux (though can't be used for zeroing unfortunately)
2022-03-02 18:35:16 +00:00
Luke Wren
96c69d0bb0
Cut in->out paths on debug halt/resume request
...
Should be harmless, because in practice these should always be driven from a register
in the DM, but still better to cut the path
2022-03-01 21:14:49 +00:00
Luke Wren
8fbffbe133
Assign full width of fifo_valid in non-reset clause (cosmetic fix)
2022-02-24 12:00:27 +00:00
Luke Wren
9ed99d8695
Use define to guard X-checks, instead of hot comments
2022-02-24 10:35:16 +00:00
Luke Wren
bf15b6c49f
Fix forward reference to net
2022-01-18 23:02:39 +00:00
Luke Wren
0a369efc06
Add single-port bus compliance. Fix adapter not re-arbitrating following an ERROR response, causing a squashed younger load-store to remain presented to the bus.
2021-12-18 15:41:05 +00:00
Luke Wren
1b0e205f87
Fix bad AMO asserts. Fix hwdata instability during stalled AMO write dphase, which meant AMOs were fundamentally broken following yesterday's datapath origami
2021-12-18 14:51:46 +00:00
Luke Wren
6b8d4913ee
Remove unnecessary mux of mw_result -> m_result
2021-12-18 01:34:25 +00:00
Luke Wren
79fec3a2f5
Overload mw_result register for capturing AMO read data. Save some LCs.
2021-12-18 01:24:26 +00:00
Luke Wren
28b53ef7b5
Delete the AMO ALU. Save around 80 LCs vs original implementation, maybe enables some more savings.
2021-12-18 00:35:13 +00:00
Luke Wren
7485269ddf
Use the branch target adder for load/store addresses. Preparing for AMO ALU deletion
2021-12-17 22:36:40 +00:00
Luke Wren
a35739baf1
Fix AMO failing to loop on global monitor write fail
2021-12-17 17:04:22 +00:00
Luke Wren
b0d28447ab
New license headers: DWTFPL -> Apache 2.0
2021-12-13 23:23:40 +00:00
Luke Wren
f1cda26bcc
Oops, try a little harder this time to ensure local monitor is cleared by sc.w errors _always_, even if lined up with trap entry stalls etc
2021-12-12 23:32:01 +00:00
Luke Wren
25b44d04cf
Add more properties wrt AMO. Fix awful bugs in interaction between AMOs and prior lr/sc, prior load/store exception, or IRQ which is asserted then deasserted. Fix sc with HRESP=1 HEXOKAY=1 not clearing the local monitor (not a bug, but unfriendly).
2021-12-12 23:24:25 +00:00
Luke Wren
88fea7acfa
Fix lockup on misaligned AMO. Add tests for misaligned/faulting AMOs.
2021-12-12 18:28:23 +00:00
Luke Wren
8a003dbbed
Make mcycle/minstret inhibited by default
2021-12-12 13:55:33 +00:00
Luke Wren
2bbc3637a2
Simplify CSR update logic. Showed promise in block synth but no difference to example soc. Still cleaner RTL.
2021-12-12 00:38:30 +00:00
Luke Wren
9460b3cd04
Add load/store and lr/sc bus fault tests. Fix lr.w not clearing local monitor when HRESP=1 HEXOKAY=1.
2021-12-11 15:52:34 +00:00
Luke Wren
3d2c912b4f
Add test script to make it easier to add software testcases
2021-12-09 22:25:18 +00:00
Luke Wren
7d2fa6a049
Fix width warnings in A instruction decode, add don't-care to bus rdata picking logic
2021-12-09 06:26:31 +00:00
Luke Wren
116e34df49
Fix commented out frontend properties which relied on non-constant past reset values
2021-12-07 20:24:29 +00:00
Luke Wren
449348f459
Fix bug where an IRQ can fire during load/store dphase, followed by dphase bus exception.
...
Result was that the exception would sample the IRQ vector PC rather than the load/store instruction PC.
Fix by fencing off on in-flight dphases before asserting the IRQ. This adds a cycle of jitter
to IRQs, but is required for correct operation without adding a full exception-gathering pipeline.
2021-12-07 19:24:53 +00:00
Luke Wren
6ef3503ef5
Add A bit to MISA, update docs
2021-12-07 05:10:20 +00:00
Luke Wren
93be227d8a
Add (currently failing) trap entry property. Fails when an IRQ arrives during a load/store data phase which subsequently excepts.
2021-12-06 20:12:23 +00:00
Luke Wren
ed22d502fd
Fix bus stall getting stuck high when a bus fault exception isn't immediately accepted by the frontend
2021-12-06 19:28:21 +00:00
Luke Wren
50d3d5d3b3
Maintain AMO IRQ holdoff when transitioning from data phase to error phase, to prevent error possibly being flushed
2021-12-06 19:27:20 +00:00
Luke Wren
29c5c8ca7f
Fix AMO stall falling through when write data phase should proceed to error phase
2021-12-06 18:28:56 +00:00
Luke Wren
8bfc089660
Slightly more strict holdoff of IRQs on AMO
2021-12-06 18:13:43 +00:00
Luke Wren
0b3629564c
Don't apply shifter assertions to rotates
2021-12-06 18:12:23 +00:00
Luke Wren
4c532240f8
Hold off IRQ when AMO is past the point of no return
2021-12-06 07:45:13 +00:00
Luke Wren
260491405a
Fix atomic instructions not asserting decode error when A extension is disabled
2021-12-06 07:28:50 +00:00
Luke Wren
cc38f46848
Fix AMO wdata valid left high when entering trap at just the right time
2021-12-06 07:28:50 +00:00
Luke Wren
12c79c0b41
Fix feature-flag for Zbs instructions in decoder
2021-12-05 02:05:35 +00:00
Luke Wren
9b9120960d
Fix missing RAW stall on sc.w succes result. Closing laptop again.
2021-12-05 01:05:01 +00:00
Luke Wren
df658d86ff
First plausibly working AMOs. Add AMOs to instruction timings list
2021-12-04 23:44:22 +00:00
Luke Wren
5c098866f2
Sketch in AMO support
2021-12-04 20:46:39 +00:00
Luke Wren
34e57f0b14
Sketch in an AMO ALU
2021-12-04 18:52:41 +00:00
Luke Wren
a8933c332d
Fix illegal issue of pipelined exclusives on the bus, and document correct timings
2021-12-04 18:23:01 +00:00
Luke Wren
5e17bb805e
Add basic support for lr/sc instructions from the A extension
2021-12-04 15:02:31 +00:00
Luke Wren
607147f280
Rewrite byte pick/sign-extend logic, preparing to handle more memops
2021-12-04 12:08:54 +00:00
Luke Wren
a988adfec8
Add RISC-V opcodes and memory operation codes for atomics
2021-12-04 11:16:24 +00:00
Luke Wren
52ba930638
Remove useless midcr.eivect feature. Make mlei left-shift its value by 2.
2021-12-04 01:17:57 +00:00
Luke Wren
dfb07822ee
Remove UART DTM
2021-12-02 02:08:16 +00:00
Luke Wren
be6b2f3f76
Fix up DTMs to use byte addressing
2021-12-02 02:05:23 +00:00
Luke Wren
1ebccb7cce
Switch DM to use byte addresses on APB, not word addresses
2021-12-02 01:47:30 +00:00
Luke Wren
c5e85dea4c
Add mconfigptr CSR
2021-12-01 03:25:56 +00:00
Luke Wren
c8afb4ac33
Add option for fast high-half multiplies
2021-11-29 18:48:02 +00:00
Luke Wren
94a3d43f27
Add Hazard3's registered marchid value to hdl and docs
2021-11-28 19:53:49 +00:00
Luke Wren
1aa9dbcddd
Fix comment typo in APB clock crossing
2021-11-28 17:40:57 +00:00
Luke Wren
e7466ae4be
Move DM data0 CSR into the M-custom space, and document this
2021-11-28 15:52:52 +00:00
Luke Wren
76172cdade
Start filling out CSR documentation. Change misa to report X=1 because of nonstandard IRQ CSRs.
2021-11-28 06:33:35 +00:00
Luke Wren
800b21d2f5
Remove event feedback path (not logical path) in priority encoder
2021-11-28 02:19:01 +00:00
Luke Wren
14a4f1a281
Add bitmanip reference vectors and test scripts. Fix bug in bclr implementation
2021-11-27 17:19:41 +00:00
Luke Wren
5d093487b7
Update README
2021-11-26 23:33:46 +00:00
Luke Wren
1bb7e33b69
Fix alignment of heap_ptr in init.S. Small ALU cleanup
2021-11-26 02:59:50 +00:00
Luke Wren
8bcec11c80
Couple more silly mistakes
2021-11-26 01:30:13 +00:00
Luke Wren
41eeb90c7d
Remove (safe) feedback path which Verilator linted on -- CXXRTL doesn't hate me any more
2021-11-26 01:29:47 +00:00
Luke Wren
998f3fdeb7
Clean up silly mistakes
2021-11-26 00:55:57 +00:00
Luke Wren
58c20a39d0
First pass at implementing bitmanip. Breaks CXXRTL. Ooop
2021-11-25 23:30:35 +00:00
Luke Wren
ed6b6a3660
Cleanup order of declaration/use of a couple of wires
2021-11-25 15:16:59 +00:00
Luke Wren
49462a8642
Add Zba/Zbb/Zbc/Zbs opcodes to rv_opcodes.vh
2021-11-23 22:11:50 +00:00
Luke Wren
e05e9a4109
Add default_nettype none at top of every file, and default_nettype wire at bottom
2021-11-23 22:10:39 +00:00
Luke Wren
0b9b706e81
Safer logic for load/store blocked by preceding WFI
2021-11-23 22:01:14 +00:00
Luke Wren
cc6a6c09ba
Vaguely implement wfi
2021-11-05 18:48:42 +00:00
Luke Wren
cfe16caf41
Remove some old todos
2021-09-05 22:20:40 +01:00
Luke Wren
e9fccffca0
Fix break and single-step on a load/store access fault dropping the exception. Better fix for halt request on definitely-excepting stage M instruction giving unreachable next-instruction DPC.
2021-09-05 04:45:38 +01:00
Luke Wren
65bfca5fdf
Fix latent bug with asynchronous debug entry during stalled load/store address phase
2021-09-04 07:49:29 +01:00