diff options
author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
---|---|---|
committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-05-06 01:02:30 +0000 |
commit | 76cb841cb886eef6b3bee341a2266c76578724ad (patch) | |
tree | f5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/nds32/include/asm/highmem.h | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 4.19.249.upstream/4.19.249upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/nds32/include/asm/highmem.h')
-rw-r--r-- | arch/nds32/include/asm/highmem.h | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/arch/nds32/include/asm/highmem.h b/arch/nds32/include/asm/highmem.h new file mode 100644 index 000000000..425d546cb --- /dev/null +++ b/arch/nds32/include/asm/highmem.h @@ -0,0 +1,65 @@ +// 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 |