Commit Graph

91 Commits

Author SHA1 Message Date
Luke Wren 6e3799eed0 First attempt at hacking in triggers, at least seems to have not broken other exception logic. Not yet tested. 2022-08-22 08:47:03 +01:00
Luke Wren d299a3ca4e More width tweaks 2022-08-20 16:11:58 +01:00
Luke Wren 5819f8eb7e Remove wrong/useless mxr logic in PMP 2022-08-08 18:45:37 +01:00
Luke Wren 15cb21ae43 First pass at implementing the new IRQ controls. Works well enough that the old tests pass :) 2022-08-07 20:51:12 +01:00
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 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 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 edfe7f601e Clear local monitor on non-debug trap entry/exit 2022-06-26 21:55:51 +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 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 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 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 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 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 ea2b8888a4 Update copyright years 2022-06-09 00:12:01 +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 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 2df1179994 Wire privilege through from core to bus masters. Tied off inside core. 2022-05-24 14:05:26 +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 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 96a9ee18e1 Add IALIGN exception to non-RVC implementations 2022-05-23 12:47:48 +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 7dc5046505 Perf option for dedicated branch comparator 2022-04-02 11:40:47 +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 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 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 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