The Svrsw60t59b extension allows to free the PTE reserved bits 60 and 59 for software to use. Reviewed-by: Alexandre Ghiti Reviewed-by: Andrew Jones Signed-off-by: Chunyan Zhang --- arch/riscv/Kconfig | 14 ++++++++++++++ arch/riscv/include/asm/hwcap.h | 1 + arch/riscv/kernel/cpufeature.c | 1 + 3 files changed, 16 insertions(+) diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index a4b233a0659e..d99df67cc7a4 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -862,6 +862,20 @@ config RISCV_ISA_ZICBOP If you don't know what to do here, say Y. +config RISCV_ISA_SVRSW60T59B + bool "Svrsw60t59b extension support for using PTE bits 60 and 59" + depends on MMU && 64BIT + depends on RISCV_ALTERNATIVE + default y + help + Adds support to dynamically detect the presence of the Svrsw60t59b + extension and enable its usage. + + The Svrsw60t59b extension allows to free the PTE reserved bits 60 + and 59 for software to use. + + If you don't know what to do here, say Y. + config TOOLCHAIN_NEEDS_EXPLICIT_ZICSR_ZIFENCEI def_bool y # https://sourceware.org/git/?p=binutils-gdb.git;a=commit;h=aed44286efa8ae8717a77d94b51ac3614e2ca6dc diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h index affd63e11b0a..f98fcb5c17d5 100644 --- a/arch/riscv/include/asm/hwcap.h +++ b/arch/riscv/include/asm/hwcap.h @@ -106,6 +106,7 @@ #define RISCV_ISA_EXT_ZAAMO 97 #define RISCV_ISA_EXT_ZALRSC 98 #define RISCV_ISA_EXT_ZICBOP 99 +#define RISCV_ISA_EXT_SVRSW60T59B 100 #define RISCV_ISA_EXT_XLINUXENVCFG 127 diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c index 743d53415572..2ba71d2d3fa3 100644 --- a/arch/riscv/kernel/cpufeature.c +++ b/arch/riscv/kernel/cpufeature.c @@ -539,6 +539,7 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = { __RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL), __RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT), __RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT), + __RISCV_ISA_EXT_DATA(svrsw60t59b, RISCV_ISA_EXT_SVRSW60T59B), __RISCV_ISA_EXT_DATA(svvptc, RISCV_ISA_EXT_SVVPTC), }; -- 2.34.1