| // 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 |
