This series implements a generic framework to parse multi-letter ISA extensions. This series is based on Tsukasa's v3 isa extension improvement series[1]. I have fixed few bugs and improved comments from that series (PATCH1-3). I have not used PATCH 4 from that series as we are not using ISA extension versioning as of now. We can add that later if required. PATCH 4 allows the probing of multi-letter extensions via a macro. It continues to use the common isa extensions between all the harts. Thus hetergenous hart systems will only see the common ISA extensions. PATCH 6 improves the /proc/cpuinfo interface for the available ISA extensions via /proc/cpuinfo. Here is the example output of /proc/cpuinfo: (with debug patches in Qemu and Linux kernel) / # cat /proc/cpuinfo processor : 0 hart : 0 isa : rv64imafdcsu isa-ext : sstc,sscofpmf mmu : sv48 processor : 1 hart : 1 isa : rv64imafdcsu isa-ext : sstc,sscofpmf mmu : sv48 processor : 2 hart : 2 isa : rv64imafdcsu isa-ext : sstc,sscofpmf mmu : sv48 processor : 3 hart : 3 isa : rv64imafdcsu isa-ext : sstc,sscofpmf mmu : sv48 Anybody adding support for any new multi-letter extensions should add an entry to the riscv_isa_ext_id and the isa extension array. E.g. The patch[2] adds the support for various ISA extensions. [1] https://lore.kernel.org/all/0f568515-a05e-8204-aae3-035975af3ee8@xxxxxxxxxxxx/T/ [2] https://github.com/atishp04/linux/commit/dc6f9200033bb5a72d8fd1a179bb272c6ade17e6 Changes from v2->v3: 1. Updated comments to mark clearly a fix required for Qemu only. 2. Fixed a bug where the 1st multi-letter extension can be present without _ 3. Added Tested by tags. Changes from v1->v2: 1. Instead of adding a separate DT property use the riscv,isa property. 2. Based on Tsukasa's v3 isa extension improvement series. Atish Patra (3): RISC-V: Implement multi-letter ISA extension probing framework RISC-V: Do no continue isa string parsing without correct XLEN RISC-V: Improve /proc/cpuinfo output for ISA extensions Tsukasa OI (3): RISC-V: Correctly print supported extensions RISC-V: Minimal parser for "riscv, isa" strings RISC-V: Extract multi-letter extension names from "riscv, isa" arch/riscv/include/asm/hwcap.h | 25 +++++++ arch/riscv/kernel/cpu.c | 44 ++++++++++- arch/riscv/kernel/cpufeature.c | 130 ++++++++++++++++++++++++++++----- 3 files changed, 178 insertions(+), 21 deletions(-) -- 2.30.2
