Commit Graph

217 Commits

Author SHA1 Message Date
Ross Thompson
cd75bf98e1 If a trap occurs concurrent with a I/DTLB miss the interlock fsm incorrectly goes into the states to handle the TLB miss.
This commit fixes this bug by keeping the interlock fsm in the T0_READY state on TrapM.
2022-01-12 14:17:16 -06:00
Ross Thompson
73c488914f Added icache access and icache miss to performance counters. 2022-01-09 22:56:56 -06:00
Ross Thompson
509a0cd3f8 Fixed bug with interlock fsm. The interlock fsm should suppress bus and cache requests by the cpu
only at the start of a request.  Pending interrupt was used to start one of these suppressions;
however because of the way the cache's fsm was separated from the bus fsm, the cache now made requests
to the bus fsm.  On a miss with write back, the inital fetch is handled correctly.  However if an
interrupt becam pending then the the next request (eviction) made by the cache was also suppressed.
This keeps the d cache fsm stuck in the STATE_MISS_EVICT_DIRTY state as it think it has made a request
to the bus fsm, but the pending interrupt ignored the request.

The solution is to modify how cpu requests are suppressed.  Instead of relying on pending interrupt
it is better to use interrupt which will be disabled if the dcache is currently processing the evict.
2022-01-07 17:55:34 -06:00
David Harris
120fb7863f Reformatted MIT license to 95 characters 2022-01-07 12:58:40 +00:00
Ross Thompson
c8d47fc7c3 Also fixed undetected bug with amo concurrent with tlb miss. It was possible for the amoalu to apply a function to the hptw readdata.
Merge branch 'main' of github.com:davidharrishmc/riscv-wally into main
2022-01-06 23:28:02 -06:00
Ross Thompson
0fddceffa6 Modified the mmu to not mux the lower 12 bits of the physical address and instead directly
assign from the input non translated virtual address.  Since the lower bits never change there is
no reason to place these lower bits on a longer critical path.
The cache and lsu were previously using the lower bits from the virtual address rather than
the physical address.  This change will allow us to keep the shorter critical path and
reduce the complexity of the lsu, ifu, and cache drawings.
2022-01-06 23:19:09 -06:00
David Harris
1d8451c2cf Capitalized LSU and IFU, changed MulDiv to MDU 2022-01-07 04:30:00 +00:00
Ross Thompson
77efcad15b Changed names of address in caches.
Removed old cache files.
2022-01-05 22:19:36 -06:00
Ross Thompson
5a2ae561a7 Updates to support fpga. 2022-01-05 18:07:23 -06:00
David Harris
32590d484c Removed more generate statements 2022-01-05 16:25:08 +00:00
David Harris
c1d6550ccb Removed generate statements 2022-01-05 14:35:25 +00:00
Ross Thompson
f89c1d91dc Renamed most signals inside cache.sv so they are agnostic to i or d. 2022-01-04 23:52:42 -06:00
Ross Thompson
9eda7c12bd the i and d caches now share common verilog. 2022-01-04 23:40:37 -06:00
Ross Thompson
b06c3b8acd parameterized the caches with the goal of using common rtl for both i and d caches. 2022-01-04 22:40:51 -06:00
Ross Thompson
06168e67e4 Switched block for line in caches. 2022-01-04 22:08:18 -06:00
David Harris
1f07470477 Merge branch 'main' of https://github.com/davidharrishmc/riscv-wally into main 2022-01-04 19:47:51 +00:00
David Harris
b36ace221e Renamed wally-pipelined to pipelined 2022-01-04 19:47:41 +00:00