[PATCH v2 00/10] RISC-V: Probe DT extension support using riscv,isa-extensions & riscv,isa-base

From: Conor Dooley
Date: Thu Jun 29 2023 - 04:32:22 EST


Hey,

Based on my latest iteration of deprecating riscv,isa [1], here's an
implementation of the new properties for Linux. The first few patches,
up to "RISC-V: split riscv_fill_hwcap() in 3", are all prep work that
further tames some of the extension related code, on top of my already
applied series that cleans up the ISA string parser.
Perhaps "RISC-V: shunt isa_ext_arr to cpufeature.c" is a bit gratuitous,
but I figured a bit of coalescing of extension related data structures
would be a good idea. Note that riscv,isa will still be used in the
absence of the new properties. Palmer suggested adding a Kconfig option
to turn off the fallback for DT, which I have gone and done. It's locked
behind the NONPORTABLE option for good reason.

In v2, I've also come up with a more reasonable name for the new
function I added & fixed up various comments from Drew and Evan.

Cheers,
Conor.

[1] https://lore.kernel.org/all/20230626-unmarked-atom-70b4d624a386@wendy/

CC: Rob Herring <robh+dt@xxxxxxxxxx>
CC: Krzysztof Kozlowski <krzysztof.kozlowski+dt@xxxxxxxxxx>
CC: Paul Walmsley <paul.walmsley@xxxxxxxxxx>
CC: Palmer Dabbelt <palmer@xxxxxxxxxxx>
CC: Albert Ou <aou@xxxxxxxxxxxxxxxxx>
CC: Andrew Jones <ajones@xxxxxxxxxxxxxxxx>
CC: Heiko Stuebner <heiko.stuebner@xxxxxxxx>
CC: Evan Green <evan@xxxxxxxxxxxx>
CC: Sunil V L <sunilvl@xxxxxxxxxxxxxxxx>
CC: linux-riscv@xxxxxxxxxxxxxxxxxxx
CC: devicetree@xxxxxxxxxxxxxxx
CC: linux-kernel@xxxxxxxxxxxxxxx

Conor Dooley (9):
RISC-V: drop a needless check in print_isa_ext()
RISC-V: shunt isa_ext_arr to cpufeature.c
RISC-V: repurpose riscv_isa_ext array in riscv_fill_hwcap()
RISC-V: add missing single letter extension definitions
RISC-V: add single letter extensions to riscv_isa_ext
RISC-V: split riscv_fill_hwcap() in 3
RISC-V: enable extension detection from new properties
RISC-V: try new extension properties in of_early_processor_hartid()
RISC-V: provide a Kconfig option to disable parsing "riscv,isa"

Heiko Stuebner (1):
RISC-V: don't parse dt/acpi isa string to get rv32/rv64

arch/riscv/Kconfig | 16 ++
arch/riscv/include/asm/hwcap.h | 16 +-
arch/riscv/kernel/cpu.c | 158 +++-------
arch/riscv/kernel/cpufeature.c | 507 +++++++++++++++++++++------------
4 files changed, 398 insertions(+), 299 deletions(-)

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2.40.1