/* SPDX-License-Identifier: GPL-2.0 */ // Copyright (C) 2005-2017 Andes Technology Corporation #ifndef _ASM_HIGHMEM_H #define _ASM_HIGHMEM_H #include <asm/proc-fns.h> #include <asm/kmap_types.h> #include <asm/fixmap.h> #include <asm/pgtable.h> /* * Right now we initialize only a single pte table. It can be extended * easily, subsequent pte tables have to be allocated in one physical * chunk of RAM. */ /* * Ordering is (from lower to higher memory addresses): * * high_memory * Persistent kmap area * PKMAP_BASE * fixed_addresses * FIXADDR_START * FIXADDR_TOP * Vmalloc area * VMALLOC_START * VMALLOC_END */ #define PKMAP_BASE ((FIXADDR_START - PGDIR_SIZE) & (PGDIR_MASK)) #define LAST_PKMAP PTRS_PER_PTE #define LAST_PKMAP_MASK (LAST_PKMAP - 1) #define PKMAP_NR(virt) (((virt) - (PKMAP_BASE)) >> PAGE_SHIFT) #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) #define kmap_prot PAGE_KERNEL static inline void flush_cache_kmaps(void) { cpu_dcache_wbinval_all(); } /* declarations for highmem.c */ extern unsigned long highstart_pfn, highend_pfn; extern pte_t *pkmap_page_table; extern void *kmap_high(struct page *page); extern void kunmap_high(struct page *page); extern void kmap_init(void); /* * The following functions are already defined by <linux/highmem.h> * when CONFIG_HIGHMEM is not set. */ #ifdef CONFIG_HIGHMEM extern void *kmap(struct page *page); extern void kunmap(struct page *page); extern void *kmap_atomic(struct page *page); extern void __kunmap_atomic(void *kvaddr); extern void *kmap_atomic_pfn(unsigned long pfn); extern struct page *kmap_atomic_to_page(void *ptr); #endif #endif