[PATCH v6 0/1] Common csr_read_num() and csr_write_num() for RISC-V
Anup Patel <[email protected]> Mon, 27 Jul 2026 14:09:00 +0530
| Newsgroups | gmane.linux.ports.riscv,gmane.linux.acpi.devel,gmane.linux.kernel |
|---|---|
| Message-ID | <[email protected]> |
Some of the RISC-V drivers (such as RISC-V PMU and ACPI CPPC) need to access CSR based on CSR number discovered from somewhere. Add common RISC-V csr_read_num() and csr_write_num() functions under arch/riscv for such drivers. These patches can be found in the riscv_csr_read_num_v6 branch at: https://github.com/avpatel/linux.git Changes since v5: - Rebased on Linux-7.2-rc5 Changes since v4: - Rebased on Linux-6.19-rc6 Changes since v3: - Rebased on Linux-6.18-rc7 - Updated commit decription of PATCH1 to reflect the fact that we are removing sanity checks on CSR number which are already taken care by csr_read_num() and csr_write_num(). Changes since v2: - Rebased on Linux-6.18-rc1 - Added reviewed-by tags Changes since v1: - Make "out_err" mandatory for csr_read_num() and csr_write_num() in PATCH2 as suggested by Sunil and Drew. This also helps further simplify csr_read_num() and csr_write_num(). Anup Patel (1): RISC-V: Add common csr_read_num() and csr_write_num() functions arch/riscv/include/asm/csr.h | 3 + arch/riscv/kernel/Makefile | 1 + arch/riscv/kernel/csr.c | 165 +++++++++++++++++++++++++++++++++++ drivers/acpi/riscv/cppc.c | 17 ++-- drivers/perf/riscv_pmu.c | 54 ++---------- 5 files changed, 184 insertions(+), 56 deletions(-) create mode 100644 arch/riscv/kernel/csr.c -- 2.43.0