1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef __UM_FIXMAP_H
 3#define __UM_FIXMAP_H
 4
 5#include <asm/processor.h>
 
 6#include <asm/archparam.h>
 7#include <asm/page.h>
 8#include <linux/threads.h>
 9
10/*
11 * Here we define all the compile-time 'special' virtual
12 * addresses. The point is to have a constant address at
13 * compile time, but to set the physical address only
14 * in the boot process. We allocate these special  addresses
15 * from the end of virtual memory (0xfffff000) backwards.
16 * Also this lets us do fail-safe vmalloc(), we
17 * can guarantee that these special addresses and
18 * vmalloc()-ed addresses never overlap.
19 *
20 * these 'compile-time allocated' memory buffers are
21 * fixed-size 4k pages. (or larger if used with an increment
22 * highger than 1) use fixmap_set(idx,phys) to associate
23 * physical memory with fixmap indices.
24 *
25 * TLB entries of such buffers will not be flushed across
26 * task switches.
27 */
28
29/*
30 * on UP currently we will have no trace of the fixmap mechanizm,
31 * no page table allocations, etc. This might change in the
32 * future, say framebuffers for the console driver(s) could be
33 * fix-mapped?
34 */
35enum fixed_addresses {
36	__end_of_fixed_addresses
37};
38
39extern void __set_fixmap (enum fixed_addresses idx,
40			  unsigned long phys, pgprot_t flags);
41
42/*
43 * used by vmalloc.c.
44 *
45 * Leave one empty page between vmalloc'ed areas and
46 * the start of the fixmap, and leave one page empty
47 * at the top of mem..
48 */
49
50#define FIXADDR_TOP	(TASK_SIZE - 2 * PAGE_SIZE)
51#define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
52#define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)
53
54#include <asm-generic/fixmap.h>
55
56#endif

 1/* SPDX-License-Identifier: GPL-2.0 */
 2#ifndef __UM_FIXMAP_H
 3#define __UM_FIXMAP_H
 4
 5#include <asm/processor.h>
 6#include <asm/kmap_types.h>
 7#include <asm/archparam.h>
 8#include <asm/page.h>
 9#include <linux/threads.h>
10
11/*
12 * Here we define all the compile-time 'special' virtual
13 * addresses. The point is to have a constant address at
14 * compile time, but to set the physical address only
15 * in the boot process. We allocate these special  addresses
16 * from the end of virtual memory (0xfffff000) backwards.
17 * Also this lets us do fail-safe vmalloc(), we
18 * can guarantee that these special addresses and
19 * vmalloc()-ed addresses never overlap.
20 *
21 * these 'compile-time allocated' memory buffers are
22 * fixed-size 4k pages. (or larger if used with an increment
23 * highger than 1) use fixmap_set(idx,phys) to associate
24 * physical memory with fixmap indices.
25 *
26 * TLB entries of such buffers will not be flushed across
27 * task switches.
28 */
29
30/*
31 * on UP currently we will have no trace of the fixmap mechanizm,
32 * no page table allocations, etc. This might change in the
33 * future, say framebuffers for the console driver(s) could be
34 * fix-mapped?
35 */
36enum fixed_addresses {
37	__end_of_fixed_addresses
38};
39
40extern void __set_fixmap (enum fixed_addresses idx,
41			  unsigned long phys, pgprot_t flags);
42
43/*
44 * used by vmalloc.c.
45 *
46 * Leave one empty page between vmalloc'ed areas and
47 * the start of the fixmap, and leave one page empty
48 * at the top of mem..
49 */
50
51#define FIXADDR_TOP	(TASK_SIZE - 2 * PAGE_SIZE)
52#define FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)
53#define FIXADDR_START	(FIXADDR_TOP - FIXADDR_SIZE)
54
55#include <asm-generic/fixmap.h>
56
57#endif