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author | Krste Asanovic <krste@eecs.berkeley.edu> | 2018-10-09 15:53:31 -0700 |
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committer | Krste Asanovic <krste@eecs.berkeley.edu> | 2018-10-09 15:53:31 -0700 |
commit | f34d887a8810b411738115b215cf2bf818660f3c (patch) | |
tree | 5697992a9984e4984e324e96ed4fbd2d095d03a9 | |
parent | 1bc8b342cd670dc809f0ebda4abce3d56597e5c8 (diff) | |
parent | 0339a73a7dc5f8fb4a15800d9b2dc6e56f1e639a (diff) | |
download | riscv-isa-manual-f34d887a8810b411738115b215cf2bf818660f3c.zip riscv-isa-manual-f34d887a8810b411738115b215cf2bf818660f3c.tar.gz riscv-isa-manual-f34d887a8810b411738115b215cf2bf818660f3c.tar.bz2 |
Merge branch 'master' of github.com:riscv/riscv-isa-manual
-rw-r--r-- | README.md | 3 | ||||
-rw-r--r-- | marchid.md | 25 | ||||
-rw-r--r-- | src/rv32.tex | 2 |
3 files changed, 29 insertions, 1 deletions
@@ -17,3 +17,6 @@ https://riscv.org/specifications/ Compiled versions of the most recent drafts of the specifications are available at https://github.com/riscv/riscv-isa-manual/releases/latest + +The canonical list of open-source RISC-V implementations' marchid CSR values +is available at https://github.com/riscv/riscv-isa-manual/blob/master/marchid.md diff --git a/marchid.md b/marchid.md new file mode 100644 index 0000000..4dbbfbd --- /dev/null +++ b/marchid.md @@ -0,0 +1,25 @@ +Open-Source RISC-V Architecture IDs +======================================== + +Every RISC-V hart provides an marchid CSR that encodes its base +microarchitecture. Any hart may report an architecture ID of 0, indicating +unspecified origin. Commercial implementations (those with nonzero mvendorid) +may encode any value in marchid with the most-significant bit set, with the +low-order bits formatted in a vendor-specific manner. Open-source +implementations (which may or may not have a nonzero mvendorid) have the +most-significant bit clear, with a globally unique pattern in the low-order +bits. + +This document contains the canonical list of open-source RISC-V implementations +and their architecture IDs. Open-source project maintainers may make pull +requests against this repository to request the allocation of an architecture +ID. + +--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- +Project Name | Maintainers | Point of Contact | Architecture ID | Project URL +------------- | ------------------------------- | ----------------------------------------------------------- | ----------------- | --------------------------------------------------- +Rocket | SiFive, UC Berkeley | [Andrew Waterman](mailto:andrew@sifive.com), SiFive | 1 | https://github.com/freechipsproject/rocket-chip +BOOM | UC Berkeley | [Christopher Celio](mailto:celio@berkeley.edu) | 2 | https://github.com/ucb-bar/riscv-boom +Ariane | PULP Platform | [Florian Zaruba](mailto:zarubaf@iis.ee.ethz.ch), ETH Zurich | 3 | https://github.com/pulp-platform/ariane +RI5CY | PULP Platform | [Frank K. Gürkaynak](mailto:kgf@iis.ee.ethz.ch), ETH Zurich | 4 | https://github.com/pulp-platform/riscv +Spike | SiFive, UC Berkeley | [Andrew Waterman](mailto:andrew@sifive.com), SiFive | 5 | https://github.com/riscv/riscv-isa-sim diff --git a/src/rv32.tex b/src/rv32.tex index 60723b6..0aab4f5 100644 --- a/src/rv32.tex +++ b/src/rv32.tex @@ -202,7 +202,7 @@ U-type \\ The RISC-V ISA keeps the source ({\em rs1} and {\em rs2}) and destination ({\em rd}) registers at the same position in all formats to simplify decoding. Except for the 5-bit immediates used in CSR -instructions (Section~\ref{sec:csrinsts}), immediates are always +instructions (Chapter~\ref{csrinsts}), immediates are always sign-extended, and are generally packed towards the leftmost available bits in the instruction and have been allocated to reduce hardware complexity. In particular, the sign bit for all immediates is always |