Beyond the CPU and GPU: SiFive in Datacenter Infrastructure
How embedded RISC-V processors in NICs, retimers, optics, switches, and security chips are overcoming modern scaling limits
Vendor:
Sifive, Inc.
Category:
CPU
S21 Area optimized 64-bit RISC V processor
The SiFive S21 Standard Core is a full-featured 64-bit embedded processor based on the S2 Series.
Overview
The SiFive S21 Standard Core is a full-featured 64-bit embedded processor based on the S2 Series. The S21 has separate Instruction and Data Buses, along with 2 banks of Tightly Integrated Memory (TIMs). The S21 is an ideal choice for area constrained applications demanding a 64-bit processor.
Key features
- RISC-V ISA - RV64IMAC
- 64-bit AXI Ports
- Machine and User Mode with 4 Region Physical Memory Protection
- 3-stage pipeline with Simultaneous Instruction and Data Access
- 2 Banks of Tightly Integrated Memory
- CLIC interrupt controller with 127 interrupts
- Advanced debug with 4 hardware breakpoints/watchpoints
- 1.6 DMIPS/MHz
- 3.2 Coremarks/MHz
Block Diagram
S21 block diagram
What’s Included?
- RTL Evaluation
- Test Bench RTL
- Software Development Kit
- FPGA Bitstream
- Documentation
Specifications
Identity
Part Number
S21
Vendor
Sifive, Inc.
Type
Silicon IP
Compute
CPU Architecture
RISC-V
Files
Note: some files may require an NDA depending on provider policy.
Provider
HQ:
USA
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Frequently asked questions about CPU IP cores
What is S21 Area optimized 64-bit RISC V processor?
S21 Area optimized 64-bit RISC V processor is a CPU IP core from Sifive, Inc. listed on Semi IP Hub.
How should engineers evaluate this CPU?
Engineers should review the overview, key features, supported foundries and nodes, maturity, deliverables, and provider information before shortlisting this CPU IP.
Can this semiconductor IP be compared with similar products?
Yes. Buyers can compare this product with similar semiconductor IP cores or IP families based on category, provider, process options, and structured technical specifications.