diff options
| author | Qinglin Pan <panqinglin2020@iscas.ac.cn> | 2023-02-09 21:16:45 +0800 |
|---|---|---|
| committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-03-07 19:39:15 -0800 |
| commit | 23ad288aaf153a78b042e10062be1a6284909f95 (patch) | |
| tree | f766a7727e62f263baad2b478a56a6e4a8a92fcf /arch/riscv/Kconfig | |
| parent | 9daca9a5b9ac35361ce2d8d5ec10b19b7048d6cd (diff) | |
riscv: mm: modify pte format for Svnapot
Add one alternative to enable/disable svnapot support, enable this static
key when "svnapot" is in the "riscv,isa" field of fdt and SVNAPOT compile
option is set. It will influence the behavior of has_svnapot. All code
dependent on svnapot should make sure that has_svnapot return true firstly.
Modify PTE definition for Svnapot, and creates some functions in pgtable.h
to mark a PTE as napot and check if it is a Svnapot PTE. Until now, only
64KB napot size is supported in spec, so some macros has only 64KB version.
Signed-off-by: Qinglin Pan <panqinglin00@gmail.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20230209131647.17245-2-panqinglin00@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Diffstat (limited to 'arch/riscv/Kconfig')
| -rw-r--r-- | arch/riscv/Kconfig | 19 |
1 files changed, 19 insertions, 0 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 7c814fbf9527..abbb7b94488d 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -397,6 +397,25 @@ config RISCV_ISA_C If you don't know what to do here, say Y. +config RISCV_ISA_SVNAPOT + bool "SVNAPOT extension support" + depends on 64BIT && MMU + default y + select RISCV_ALTERNATIVE + help + Allow kernel to detect the SVNAPOT ISA-extension dynamically at boot + time and enable its usage. + + The SVNAPOT extension is used to mark contiguous PTEs as a range + of contiguous virtual-to-physical translations for a naturally + aligned power-of-2 (NAPOT) granularity larger than the base 4KB page + size. When HUGETLBFS is also selected this option unconditionally + allocates some memory for each NAPOT page size supported by the kernel. + When optimizing for low memory consumption and for platforms without + the SVNAPOT extension, it may be better to say N here. + + If you don't know what to do here, say Y. + config RISCV_ISA_SVPBMT bool "SVPBMT extension support" depends on 64BIT && MMU |