diff options
Diffstat (limited to 'arch/powerpc/include/asm/nohash/32/pte-44x.h')
| -rw-r--r-- | arch/powerpc/include/asm/nohash/32/pte-44x.h | 40 |
1 files changed, 23 insertions, 17 deletions
diff --git a/arch/powerpc/include/asm/nohash/32/pte-44x.h b/arch/powerpc/include/asm/nohash/32/pte-44x.h index 0656ff81e5b0..da0469928273 100644 --- a/arch/powerpc/include/asm/nohash/32/pte-44x.h +++ b/arch/powerpc/include/asm/nohash/32/pte-44x.h @@ -1,3 +1,4 @@ +/* SPDX-License-Identifier: GPL-2.0 */ #ifndef _ASM_POWERPC_NOHASH_32_PTE_44x_H #define _ASM_POWERPC_NOHASH_32_PTE_44x_H #ifdef __KERNEL__ @@ -55,29 +56,19 @@ * above bits. Note that the bit values are CPU specific, not architecture * specific. * - * The kernel PTE entry holds an arch-dependent swp_entry structure under - * certain situations. In other words, in such situations some portion of - * the PTE bits are used as a swp_entry. In the PPC implementation, the - * 3-24th LSB are shared with swp_entry, however the 0-2nd three LSB still - * hold protection values. That means the three protection bits are - * reserved for both PTE and SWAP entry at the most significant three - * LSBs. - * - * There are three protection bits available for SWAP entry: - * _PAGE_PRESENT - * _PAGE_HASHPTE (if HW has) - * - * So those three bits have to be inside of 0-2nd LSB of PTE. - * + * The kernel PTE entry can be an ordinary PTE mapping a page or a special swap + * PTE. In case of a swap PTE, LSB 2-24 are used to store information regarding + * the swap entry. However LSB 0-1 still hold protection values, for example, + * to distinguish swap PTEs from ordinary PTEs, and must be used with care. */ #define _PAGE_PRESENT 0x00000001 /* S: PTE valid */ -#define _PAGE_RW 0x00000002 /* S: Write permission */ +#define _PAGE_WRITE 0x00000002 /* S: Write permission */ #define _PAGE_EXEC 0x00000004 /* H: Execute permission */ -#define _PAGE_ACCESSED 0x00000008 /* S: Page referenced */ +#define _PAGE_READ 0x00000008 /* S: Read permission */ #define _PAGE_DIRTY 0x00000010 /* S: Page dirty */ #define _PAGE_SPECIAL 0x00000020 /* S: Special page */ -#define _PAGE_USER 0x00000040 /* S: User page */ +#define _PAGE_ACCESSED 0x00000040 /* S: Page referenced */ #define _PAGE_ENDIAN 0x00000080 /* H: E bit */ #define _PAGE_GUARDED 0x00000100 /* H: G bit */ #define _PAGE_COHERENT 0x00000200 /* H: M bit */ @@ -88,10 +79,25 @@ #define _PMD_PRESENT 0 #define _PMD_PRESENT_MASK (PAGE_MASK) #define _PMD_BAD (~PAGE_MASK) +#define _PMD_USER 0 /* ERPN in a PTE never gets cleared, ignore it */ #define _PTE_NONE_MASK 0xffffffff00000000ULL +/* + * We define 2 sets of base prot bits, one for basic pages (ie, + * cacheable kernel and user pages) and one for non cacheable + * pages. We always set _PAGE_COHERENT when SMP is enabled or + * the processor might need it for DMA coherency. + */ +#define _PAGE_BASE_NC (_PAGE_PRESENT | _PAGE_ACCESSED) +#if defined(CONFIG_SMP) +#define _PAGE_BASE (_PAGE_BASE_NC | _PAGE_COHERENT) +#else +#define _PAGE_BASE (_PAGE_BASE_NC) +#endif + +#include <asm/pgtable-masks.h> #endif /* __KERNEL__ */ #endif /* _ASM_POWERPC_NOHASH_32_PTE_44x_H */ |