1b2441318SGreg Kroah-Hartman /* SPDX-License-Identifier: GPL-2.0 */ 2b8b572e1SStephen Rothwell /* 3b8b572e1SStephen Rothwell * highmem.h: virtual kernel memory mappings for high memory 4b8b572e1SStephen Rothwell * 5b8b572e1SStephen Rothwell * PowerPC version, stolen from the i386 version. 6b8b572e1SStephen Rothwell * 7b8b572e1SStephen Rothwell * Used in CONFIG_HIGHMEM systems for memory pages which 8b8b572e1SStephen Rothwell * are not addressable by direct kernel virtual addresses. 9b8b572e1SStephen Rothwell * 10b8b572e1SStephen Rothwell * Copyright (C) 1999 Gerhard Wichert, Siemens AG 11b8b572e1SStephen Rothwell * Gerhard.Wichert@pdb.siemens.de 12b8b572e1SStephen Rothwell * 13b8b572e1SStephen Rothwell * 14b8b572e1SStephen Rothwell * Redesigned the x86 32-bit VM architecture to deal with 15b8b572e1SStephen Rothwell * up to 16 Terrabyte physical memory. With current x86 CPUs 16b8b572e1SStephen Rothwell * we now support up to 64 Gigabytes physical RAM. 17b8b572e1SStephen Rothwell * 18b8b572e1SStephen Rothwell * Copyright (C) 1999 Ingo Molnar <mingo@redhat.com> 19b8b572e1SStephen Rothwell */ 20b8b572e1SStephen Rothwell 21b8b572e1SStephen Rothwell #ifndef _ASM_HIGHMEM_H 22b8b572e1SStephen Rothwell #define _ASM_HIGHMEM_H 23b8b572e1SStephen Rothwell 24b8b572e1SStephen Rothwell #ifdef __KERNEL__ 25b8b572e1SStephen Rothwell 26b8b572e1SStephen Rothwell #include <linux/interrupt.h> 2745ef5992SChristophe Leroy #include <asm/cacheflush.h> 28b8b572e1SStephen Rothwell #include <asm/page.h> 29b8b572e1SStephen Rothwell #include <asm/fixmap.h> 30b8b572e1SStephen Rothwell 31b8b572e1SStephen Rothwell extern pte_t *pkmap_page_table; 32b8b572e1SStephen Rothwell 33b8b572e1SStephen Rothwell /* 34b8b572e1SStephen Rothwell * Right now we initialize only a single pte table. It can be extended 35b8b572e1SStephen Rothwell * easily, subsequent pte tables have to be allocated in one physical 36b8b572e1SStephen Rothwell * chunk of RAM. 37b8b572e1SStephen Rothwell */ 38ca9153a3SIlya Yanok /* 39e1240122SYuri Tikhonov * We use one full pte table with 4K pages. And with 16K/64K/256K pages pte 40e1240122SYuri Tikhonov * table covers enough memory (32MB/512MB/2GB resp.), so that both FIXMAP 41e1240122SYuri Tikhonov * and PKMAP can be placed in a single pte table. We use 512 pages for PKMAP 42e1240122SYuri Tikhonov * in case of 16K/64K/256K page sizes. 43ca9153a3SIlya Yanok */ 44ca9153a3SIlya Yanok #ifdef CONFIG_PPC_4K_PAGES 45ca9153a3SIlya Yanok #define PKMAP_ORDER PTE_SHIFT 46ca9153a3SIlya Yanok #else 47e1240122SYuri Tikhonov #define PKMAP_ORDER 9 48ca9153a3SIlya Yanok #endif 49ca9153a3SIlya Yanok #define LAST_PKMAP (1 << PKMAP_ORDER) 50ca9153a3SIlya Yanok #ifndef CONFIG_PPC_4K_PAGES 51ca9153a3SIlya Yanok #define PKMAP_BASE (FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) 52ca9153a3SIlya Yanok #else 53b8b572e1SStephen Rothwell #define PKMAP_BASE ((FIXADDR_START - PAGE_SIZE*(LAST_PKMAP + 1)) & PMD_MASK) 54ca9153a3SIlya Yanok #endif 55ca9153a3SIlya Yanok #define LAST_PKMAP_MASK (LAST_PKMAP-1) 56b8b572e1SStephen Rothwell #define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT) 57b8b572e1SStephen Rothwell #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) 58b8b572e1SStephen Rothwell 59b8b572e1SStephen Rothwell #define flush_cache_kmaps() flush_cache_all() 60b8b572e1SStephen Rothwell 61*78502582SThomas Gleixner #define arch_kmap_local_set_pte(mm, vaddr, ptep, ptev) \ 62*78502582SThomas Gleixner __set_pte_at(mm, vaddr, ptep, ptev, 1) 6347da42b2SThomas Gleixner #define arch_kmap_local_post_map(vaddr, pteval) \ 6447da42b2SThomas Gleixner local_flush_tlb_page(NULL, vaddr) 6547da42b2SThomas Gleixner #define arch_kmap_local_post_unmap(vaddr) \ 6647da42b2SThomas Gleixner local_flush_tlb_page(NULL, vaddr) 6747da42b2SThomas Gleixner 68b8b572e1SStephen Rothwell #endif /* __KERNEL__ */ 69b8b572e1SStephen Rothwell 70b8b572e1SStephen Rothwell #endif /* _ASM_HIGHMEM_H */ 71