1 /*
2 * fixmap.h: compile-time virtual memory allocation
3 *
4 * This file is subject to the terms and conditions of the GNU General Public
5 * License. See the file "COPYING" in the main directory of this archive
6 * for more details.
7 *
8 * Copyright (C) 1998 Ingo Molnar
9 *
10 * Copyright 2008 Freescale Semiconductor Inc.
11 * Port to powerpc added by Kumar Gala
12 */
13
14 #ifndef _ASM_FIXMAP_H
15 #define _ASM_FIXMAP_H
16
17 #ifndef __ASSEMBLY__
18 #include <asm/page.h>
19 #include <asm/pgtable.h>
20 #ifdef CONFIG_HIGHMEM
21 #include <linux/threads.h>
22 #include <asm/kmap_types.h>
23 #endif
24
25 #define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE))
26
27 /*
28 * Here we define all the compile-time 'special' virtual
29 * addresses. The point is to have a constant address at
30 * compile time, but to set the physical address only
31 * in the boot process. We allocate these special addresses
32 * from the end of virtual memory (0xfffff000) backwards.
33 * Also this lets us do fail-safe vmalloc(), we
34 * can guarantee that these special addresses and
35 * vmalloc()-ed addresses never overlap.
36 *
37 * these 'compile-time allocated' memory buffers are
38 * fixed-size 4k pages. (or larger if used with an increment
39 * highger than 1) use fixmap_set(idx,phys) to associate
40 * physical memory with fixmap indices.
41 *
42 * TLB entries of such buffers will not be flushed across
43 * task switches.
44 */
45 enum fixed_addresses {
46 FIX_HOLE,
47 /* reserve the top 128K for early debugging purposes */
48 FIX_EARLY_DEBUG_TOP = FIX_HOLE,
49 FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+((128*1024)/PAGE_SIZE)-1,
50 #ifdef CONFIG_HIGHMEM
51 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
52 FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
53 #endif
54 #ifdef CONFIG_PPC_8xx
55 /* For IMMR we need an aligned 512K area */
56 #define FIX_IMMR_SIZE (512 * 1024 / PAGE_SIZE)
57 FIX_IMMR_START,
58 FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 +
59 FIX_IMMR_SIZE,
60 #endif
61 /* FIX_PCIE_MCFG, */
62 __end_of_fixed_addresses
63 };
64
65 #define __FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
66 #define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE)
67
68 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG
69
70 #include <asm-generic/fixmap.h>
71
__set_fixmap(enum fixed_addresses idx,phys_addr_t phys,pgprot_t flags)72 static inline void __set_fixmap(enum fixed_addresses idx,
73 phys_addr_t phys, pgprot_t flags)
74 {
75 map_kernel_page(fix_to_virt(idx), phys, pgprot_val(flags));
76 }
77
78 #endif /* !__ASSEMBLY__ */
79 #endif
80
