diff options
author | Qinglin Pan <panqinglin2020@iscas.ac.cn> | 2023-02-09 16:16:45 +0300 |
---|---|---|
committer | Palmer Dabbelt <palmer@rivosinc.com> | 2023-03-08 06:39:15 +0300 |
commit | 23ad288aaf153a78b042e10062be1a6284909f95 (patch) | |
tree | f766a7727e62f263baad2b478a56a6e4a8a92fcf /arch/riscv/include/asm/pgtable.h | |
parent | 9daca9a5b9ac35361ce2d8d5ec10b19b7048d6cd (diff) | |
download | linux-23ad288aaf153a78b042e10062be1a6284909f95.tar.xz |
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/include/asm/pgtable.h')
-rw-r--r-- | arch/riscv/include/asm/pgtable.h | 39 |
1 files changed, 38 insertions, 1 deletions
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h index 2a88362dffa5..76502bc7bef2 100644 --- a/arch/riscv/include/asm/pgtable.h +++ b/arch/riscv/include/asm/pgtable.h @@ -264,10 +264,47 @@ static inline pte_t pud_pte(pud_t pud) return __pte(pud_val(pud)); } +#ifdef CONFIG_RISCV_ISA_SVNAPOT + +static __always_inline bool has_svnapot(void) +{ + return riscv_has_extension_likely(RISCV_ISA_EXT_SVNAPOT); +} + +static inline unsigned long pte_napot(pte_t pte) +{ + return pte_val(pte) & _PAGE_NAPOT; +} + +static inline pte_t pte_mknapot(pte_t pte, unsigned int order) +{ + int pos = order - 1 + _PAGE_PFN_SHIFT; + unsigned long napot_bit = BIT(pos); + unsigned long napot_mask = ~GENMASK(pos, _PAGE_PFN_SHIFT); + + return __pte((pte_val(pte) & napot_mask) | napot_bit | _PAGE_NAPOT); +} + +#else + +static __always_inline bool has_svnapot(void) { return false; } + +static inline unsigned long pte_napot(pte_t pte) +{ + return 0; +} + +#endif /* CONFIG_RISCV_ISA_SVNAPOT */ + /* Yields the page frame number (PFN) of a page table entry */ static inline unsigned long pte_pfn(pte_t pte) { - return __page_val_to_pfn(pte_val(pte)); + unsigned long res = __page_val_to_pfn(pte_val(pte)); + + if (has_svnapot() && pte_napot(pte)) + res = res & (res - 1UL); + + return res; } #define pte_page(x) pfn_to_page(pte_pfn(x)) |