1 /* SPDX-License-Identifier: GPL-2.0 */ 2 // Copyright (C) 2005-2017 Andes Technology Corporation 3 4 #ifndef _ASM_HIGHMEM_H 5 #define _ASM_HIGHMEM_H 6 7 #include <asm/proc-fns.h> 8 #include <asm/kmap_types.h> 9 #include <asm/fixmap.h> 10 11 /* 12 * Right now we initialize only a single pte table. It can be extended 13 * easily, subsequent pte tables have to be allocated in one physical 14 * chunk of RAM. 15 */ 16 /* 17 * Ordering is (from lower to higher memory addresses): 18 * 19 * high_memory 20 * Persistent kmap area 21 * PKMAP_BASE 22 * fixed_addresses 23 * FIXADDR_START 24 * FIXADDR_TOP 25 * Vmalloc area 26 * VMALLOC_START 27 * VMALLOC_END 28 */ 29 #define PKMAP_BASE ((FIXADDR_START - PGDIR_SIZE) & (PGDIR_MASK)) 30 #define LAST_PKMAP PTRS_PER_PTE 31 #define LAST_PKMAP_MASK (LAST_PKMAP - 1) 32 #define PKMAP_NR(virt) (((virt) - (PKMAP_BASE)) >> PAGE_SHIFT) 33 #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) 34 flush_cache_kmaps(void)35static inline void flush_cache_kmaps(void) 36 { 37 cpu_dcache_wbinval_all(); 38 } 39 40 /* declarations for highmem.c */ 41 extern unsigned long highstart_pfn, highend_pfn; 42 43 extern pte_t *pkmap_page_table; 44 45 extern void kmap_init(void); 46 47 /* 48 * The following functions are already defined by <linux/highmem.h> 49 * when CONFIG_HIGHMEM is not set. 50 */ 51 #ifdef CONFIG_HIGHMEM 52 extern void *kmap_atomic_pfn(unsigned long pfn); 53 #endif 54 55 #endif 56