RISC-V: mm: Update pgtable comment documentation

sv57 is supported in the kernel so pgtable.h should reflect that.

Signed-off-by: Charlie Jenkins <charlie@rivosinc.com>
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Link: https://lore.kernel.org/r/20230809232218.849726-4-charlie@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
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Charlie Jenkins 2023-08-09 16:22:03 -07:00 committed by Palmer Dabbelt
parent 4d0c04eac0
commit 26eee2bfc4
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1 changed files with 5 additions and 3 deletions

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@ -851,14 +851,16 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
* Task size is 0x4000000000 for RV64 or 0x9fc00000 for RV32.
* Note that PGDIR_SIZE must evenly divide TASK_SIZE.
* Task size is:
* - 0x9fc00000 (~2.5GB) for RV32.
* - 0x4000000000 ( 256GB) for RV64 using SV39 mmu
* - 0x800000000000 ( 128TB) for RV64 using SV48 mmu
* - 0x9fc00000 (~2.5GB) for RV32.
* - 0x4000000000 ( 256GB) for RV64 using SV39 mmu
* - 0x800000000000 ( 128TB) for RV64 using SV48 mmu
* - 0x100000000000000 ( 64PB) for RV64 using SV57 mmu
*
* Note that PGDIR_SIZE must evenly divide TASK_SIZE since "RISC-V
* Instruction Set Manual Volume II: Privileged Architecture" states that
* "load and store effective addresses, which are 64bits, must have bits
* 6348 all equal to bit 47, or else a page-fault exception will occur."
* Similarly for SV57, bits 6357 must be equal to bit 56.
*/
#ifdef CONFIG_64BIT
#define TASK_SIZE_64 (PGDIR_SIZE * PTRS_PER_PGD / 2)