lowRISC/ibex

View on GitHub

Ibex is a small 32-bit RISC-V CPU core with high-level of verification (previously known as zero-riscy)

Stars: 2.1k
Forks: 810
Open beginner issues: 0
Indexed issues: 205
Avg merge: 5d 23h
Merged PRs (30d): 9

Dominant language: SystemVerilog
License: Apache-2.0
Last GitHub push: Sep 17, 2026
Latest indexed: Sep 19, 2026
Contributing guide: Contributing guide
Code of conduct: No code of conduct
Beginner labels: good first issue

Beginner friendly Everything

Open All

205 open issues indexed

[rtl] Check and fix IRQ entry latency for 2-stage config Open

Component:RTL Type:Enhancement

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#1332 · Opened Apr 13, 2021
[Component:DV] running directed c/asm tests Open

Component:DV Type:Enhancement Type:Question

Difficulty 4/5 3-5 days Newbie friendliness 30/100

lowRISC/ibex#1321 · 1 comment · Opened Apr 1, 2021
Add RISC-V Compliance v2 check Open

Component:DV Type:Task

Difficulty 5/5 Over a week Newbie friendliness 15/100

lowRISC/ibex#1233 · 1 comment · Opened Jan 11, 2021
[tracking] Activate pseudo zext.[b|h] decoding Open

Component:DV Type:Task

Difficulty 3/5 1-2 days Newbie friendliness 25/100

lowRISC/ibex#1228 · 3 comments · Opened Jan 9, 2021
Spike timeouts in riscv_pmp_full_random_test with experimental-maxperf-pmp-bmfull-icache config Open

Component:DV Type:Bug

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#1223 · 6 comments · Opened Jan 7, 2021
Fix Xcelium warnings and errors with simple system Open

Component:RTL Type:Bug

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#1196 · 5 comments · Opened Nov 18, 2020
[syn] Add more robust error detection/reporting to synthesis flow Open

Component:Tool-and-Build Type:Task

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#1194 · 2 comments · Opened Nov 16, 2020
[docs] Clean up line breaks Open

Component:Doc Good First Issue Type:Cleanup

Difficulty 4/5 3-5 days Newbie friendliness 35/100

lowRISC/ibex#1191 · 6 comments · Opened Nov 13, 2020
riscv_mmu_stress_test test fail Open

Component:DV Type:Bug

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#1165 · 8 comments · Opened Nov 2, 2020
Illegal Instruction Retires Open

Type:Bug

lowRISC/ibex#1132 · 6 comments · 1 assignee · Opened Oct 14, 2020
Create a Spike extension module for Ibex-specific CSRs Open

Component:Tool-and-Build Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#1131 · Opened Oct 14, 2020
[simple-system] Linker script updates Open

Component:Tool-and-Build Type:Enhancement

lowRISC/ibex#1116 · 1 comment · 1 assignee · Opened Sep 23, 2020
Enable a way to configure the Cache characteristics from the Ibex Core Top Open

Component:RTL Type:Enhancement

Difficulty 4/5 3-5 days Newbie friendliness 35/100

lowRISC/ibex#1103 · 4 comments · Opened Sep 8, 2020
[rtl] Use IF skid buffer to reduce mis-predict penalty for branch prediction Open

Component:RTL Type:Task

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#1097 · Opened Aug 27, 2020
Parallelize UVM tests without LSF (in CI) Open

Component:Tool-and-Build Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#1085 · 2 comments · 1 reaction · Opened Aug 21, 2020
Does NMI need to be precise? Open

Type:Question Type:Spec-Compliance

Difficulty 5/5 Over a week Newbie friendliness 20/100

lowRISC/ibex#1053 · 1 comment · Opened Jul 28, 2020
Yosys syn flow: Use fusesoc Open

Component:Tool-and-Build Type:Enhancement

Difficulty 4/5 3-5 days Newbie friendliness 35/100

lowRISC/ibex#1006 · 4 comments · Opened Jul 3, 2020
[DV] Remove all copies of OpenTitan files except when vendored in Open

Component:DV Type:Bug

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#985 · 4 comments · Opened Jun 23, 2020
Investigate special case direct forwarding from loads Open

Component:RTL Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#976 · 1 comment · Opened Jun 19, 2020
PMP: Try to implement support for 64 regions Open

Component:RTL Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#908 · 1 comment · Opened May 28, 2020
Testing for RISC-V trace interface Open

Component:DV Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 20/100

lowRISC/ibex#900 · 1 comment · Opened May 26, 2020
Add RISC-V Trace Specification-compliant interface Open

Component:RTL Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#899 · Opened May 26, 2020
DV: Use FuseSoC instead of hardcoding file list in ibex_dv.f Open

Component:DV Type:Task

lowRISC/ibex#893 · 1 assignee · Opened May 22, 2020
[rtl] Dummy instruction enhancements Open

Type:Enhancement

lowRISC/ibex#885 · 1 comment · 1 assignee · Opened May 21, 2020
Add AscentLint lint target to Ibex Open

Component:Tool-and-Build Type:Enhancement

Difficulty 4/5 3-5 days Newbie friendliness 30/100

lowRISC/ibex#784 · 2 comments · Opened Apr 16, 2020
Check possibility of input silencing for critical blocks Open

Component:RTL Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#783 · 1 comment · Opened Apr 16, 2020
Long path through multdiv into IF stage Open

Component:RTL Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#780 · 3 comments · Opened Apr 15, 2020
Introduce PMA handling to Ibex Open

Component:RTL Type:Task

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#764 · 16 comments · Opened Apr 6, 2020
Check alignment of Ibex bus interface with "OBI" bus standard Open

Component:RTL Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#758 · 1 comment · Opened Apr 1, 2020
Ease of adapting Ibex memory protocol to tilelink for non 32-bit access Open

Component:RTL Type:Task

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#757 · 10 comments · Opened Apr 1, 2020
Deal with the replications of Ibex parameter sets across .core files Open

Component:Tool-and-Build Type:Cleanup Type:Task

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#753 · 2 comments · Opened Mar 31, 2020
[doc] Document basic commands for running/checking Ibex Open

Component:Doc Good First Issue Type:Task

Difficulty 2/5 1-3 hours Newbie friendliness 68/100

lowRISC/ibex#741 · 3 comments · Opened Mar 27, 2020
[doc] Document support Ibex configurations Open

Component:Doc Component:Tool-and-Build Type:Task

Difficulty 3/5 1-2 days Newbie friendliness 38/100

lowRISC/ibex#740 · 1 comment · Opened Mar 27, 2020
[fpv] Write properties for top-level Ibex interface Open

Component:DV Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#719 · Opened Mar 20, 2020
Possible optimisations in UVM Makefile Open

Component:DV Type:Enhancement

Difficulty 3/5 1-2 days Newbie friendliness 25/100

lowRISC/ibex#689 · Opened Mar 12, 2020
[tracking] Use Verible's verilog_format for code formatting Open

Component:Tool-and-Build Type:Enhancement

Difficulty 4/5 3-5 days Newbie friendliness 30/100

lowRISC/ibex#687 · 2 comments · Opened Mar 11, 2020
Yosys CI checks Open

Component:Tool-and-Build Type:Task

Difficulty 4/5 3-5 days Newbie friendliness 25/100

lowRISC/ibex#653 · 1 comment · Opened Mar 4, 2020
Feedthrough path detection Open

Component:Tool-and-Build Type:Task

Difficulty 5/5 Over a week Newbie friendliness 20/100

lowRISC/ibex#651 · Opened Mar 4, 2020
Try out svlint Open

Component:Tool-and-Build Good First Issue Type:Enhancement

Difficulty 5/5 Over a week Newbie friendliness 15/100

lowRISC/ibex#644 · 7 comments · Opened Mar 2, 2020
Tracer: Fix sensitivity warnings Open

Component:DV Type:Bug

Difficulty 3/5 1-2 days Newbie friendliness 30/100

lowRISC/ibex#619 · Opened Feb 21, 2020
Docs: Use rstflattable for tables Open

Component:Doc Type:Enhancement

Difficulty 3/5 1-2 days Newbie friendliness 35/100

lowRISC/ibex#595 · Opened Feb 10, 2020
Make ibex_tracer_file_base a known plusarg in .core files Open

Component:Tool-and-Build Type:Enhancement

Difficulty 2/5 1-3 hours Newbie friendliness 45/100

lowRISC/ibex#586 · Opened Feb 5, 2020
syn: Remove copy of prim_clock_gating.v and use shared version instead Open

Component:RTL Type:Task

Difficulty 2/5 1-3 hours Newbie friendliness 45/100

lowRISC/ibex#501 · 3 comments · Opened Nov 29, 2019
Modify/Extend Simple System to be a more generic base Open

Type:Task

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#438 · 1 comment · Opened Oct 30, 2019
Add riscv compliance reference to doc Open

Component:Doc Type:Enhancement

Difficulty 1/5 Under an hour Newbie friendliness 35/100

lowRISC/ibex#381 · 1 comment · Opened Oct 8, 2019
Create page tracking tape out information (and maybe comparison?) Open

Component:Doc Type:Task

Difficulty 5/5 Over a week Newbie friendliness 25/100

lowRISC/ibex#309 · 1 comment · 2 reactions · Opened Sep 11, 2019
Implement time CSR Open

Component:Doc Component:RTL Type:Enhancement

Difficulty 4/5 3-5 days Newbie friendliness 35/100

lowRISC/ibex#278 · Opened Sep 2, 2019
DV: Test performance counters Open

Component:DV Priority:P3 Type:Enhancement

lowRISC/ibex#238 · 3 comments · 1 assignee · Opened Aug 13, 2019
Provide software using PMP Open

Type:Task

lowRISC/ibex#219 · 1 assignee · Opened Aug 6, 2019
Provide software exercising U-Mode Open

Type:Task

lowRISC/ibex#218 · 1 assignee · Opened Aug 6, 2019

lowRISC/ibex

Get new issues in your inbox