diff options
| author |   Greentime Hu <greentime@andestech.com> | 2017-10-24 14:53:31 +0800 |
|---|---|---|
| committer | Greentime Hu <greentime@andestech.com> | 2018-02-22 10:44:31 +0800 |
| commit | 2e1aecb970b7662cf3d53d2d18a54c17f1eb55b8 (patch) | |
| tree | 572eba03a7c2b99f672d74e9dbbe70a32a399104 /arch/nds32/include/asm/highmem.h | |
| parent | nds32: Exception handling (diff) | |
| download | linux-dev-2e1aecb970b7662cf3d53d2d18a54c17f1eb55b8.tar.xz linux-dev-2e1aecb970b7662cf3d53d2d18a54c17f1eb55b8.zip | |
nds32: MMU definitions
This patch includes virtual memory layout, PHYS_OFFSET is defined as 0x0. It
also includes the 4KB/8KB page size configurations and pte operations.
Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
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 000000000000..425d546cb059 --- /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 |