diff options
| author | Conor Dooley <conor.dooley@microchip.com> | 2023-06-07 23:28:31 +0300 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-06-21 17:45:19 +0300 |
| commit | 07edc32779e3dfe164970fc254291258277219c9 (patch) | |
| tree | 80b70e506f16a268d6d5624a236d652cbfc695b0 /arch/riscv/kernel | |
| parent | 1e5cae98e46d15f4dc7c675e1bd0ed2172ea181c (diff) | |
| download | linux-07edc32779e3dfe164970fc254291258277219c9.tar.xz | |
RISC-V: always report presence of extensions formerly part of the base ISA
Of these four extensions, two were part of the base ISA when the port was
written and are required by the kernel. The other two are implied when
`i` is in riscv,isa on DT systems.
There's not much that userspace can do with this extra information, but
there is no harm in reporting an ISA string that closer resembles the
current versions of the specifications either.
Signed-off-by: Conor Dooley <conor.dooley@microchip.com>
Link: https://lore.kernel.org/r/20230607-nest-collision-5796b6be8be6@spud
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/kernel')
| -rw-r--r-- | arch/riscv/kernel/cpu.c | 4 | ||||
| -rw-r--r-- | arch/riscv/kernel/cpufeature.c | 17 |
2 files changed, 21 insertions, 0 deletions
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c index dfb4a2a61050..6aea6412cf65 100644 --- a/arch/riscv/kernel/cpu.c +++ b/arch/riscv/kernel/cpu.c @@ -208,7 +208,11 @@ arch_initcall(riscv_cpuinfo_init); static struct riscv_isa_ext_data isa_ext_arr[] = { __RISCV_ISA_EXT_DATA(zicbom, RISCV_ISA_EXT_ZICBOM), __RISCV_ISA_EXT_DATA(zicboz, RISCV_ISA_EXT_ZICBOZ), + __RISCV_ISA_EXT_DATA(zicntr, RISCV_ISA_EXT_ZICNTR), + __RISCV_ISA_EXT_DATA(zicsr, RISCV_ISA_EXT_ZICSR), + __RISCV_ISA_EXT_DATA(zifencei, RISCV_ISA_EXT_ZIFENCEI), __RISCV_ISA_EXT_DATA(zihintpause, RISCV_ISA_EXT_ZIHINTPAUSE), + __RISCV_ISA_EXT_DATA(zihpm, RISCV_ISA_EXT_ZIHPM), __RISCV_ISA_EXT_DATA(zbb, RISCV_ISA_EXT_ZBB), __RISCV_ISA_EXT_DATA(smaia, RISCV_ISA_EXT_SMAIA), __RISCV_ISA_EXT_DATA(ssaia, RISCV_ISA_EXT_SSAIA), diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 84dc44a3e6e5..d21f7e8a33ef 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -312,6 +312,23 @@ void __init riscv_fill_hwcap(void) } /* + * Linux requires the following extensions, so we may as well + * always set them. + */ + set_bit(RISCV_ISA_EXT_ZICSR, this_isa); + set_bit(RISCV_ISA_EXT_ZIFENCEI, this_isa); + + /* + * These ones were as they were part of the base ISA when the + * port & dt-bindings were upstreamed, and so can be set + * unconditionally where `i` is in riscv,isa on DT systems. + */ + if (acpi_disabled) { + set_bit(RISCV_ISA_EXT_ZICNTR, this_isa); + set_bit(RISCV_ISA_EXT_ZIHPM, this_isa); + } + + /* * All "okay" hart should have same isa. Set HWCAP based on * common capabilities of every "okay" hart, in case they don't * have. |