2 * fixmap.h: compile-time virtual memory allocation
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
8 * Copyright (C) 1998 Ingo Molnar
10 * Support of BIGMEM added by Gerhard Wichert, Siemens AG, July 1999
13 #ifndef _ASM_FIXMAP_32_H
14 #define _ASM_FIXMAP_32_H
17 /* used by vmalloc.c, vsyscall.lds.S.
19 * Leave one empty page between vmalloc'ed areas and
20 * the start of the fixmap.
22 extern unsigned long __FIXADDR_TOP;
23 #define FIXADDR_USER_START __fix_to_virt(FIX_VDSO)
24 #define FIXADDR_USER_END __fix_to_virt(FIX_VDSO - 1)
27 #include <linux/kernel.h>
29 #include <asm/apicdef.h>
32 #include <linux/threads.h>
33 #include <asm/kmap_types.h>
37 * Here we define all the compile-time 'special' virtual
38 * addresses. The point is to have a constant address at
39 * compile time, but to set the physical address only
40 * in the boot process. We allocate these special addresses
41 * from the end of virtual memory (0xfffff000) backwards.
42 * Also this lets us do fail-safe vmalloc(), we
43 * can guarantee that these special addresses and
44 * vmalloc()-ed addresses never overlap.
46 * these 'compile-time allocated' memory buffers are
47 * fixed-size 4k pages. (or larger if used with an increment
48 * highger than 1) use fixmap_set(idx,phys) to associate
49 * physical memory with fixmap indices.
51 * TLB entries of such buffers will not be flushed across
54 enum fixed_addresses {
58 FIX_EARLYCON_MEM_BASE,
59 #ifdef CONFIG_X86_LOCAL_APIC
60 FIX_APIC_BASE, /* local (CPU) APIC) -- required for SMP or not */
62 #ifdef CONFIG_X86_IO_APIC
64 FIX_IO_APIC_BASE_END = FIX_IO_APIC_BASE_0 + MAX_IO_APICS-1,
66 #ifdef CONFIG_X86_VISWS_APIC
67 FIX_CO_CPU, /* Cobalt timer */
68 FIX_CO_APIC, /* Cobalt APIC Redirection Table */
69 FIX_LI_PCIA, /* Lithium PCI Bridge A */
70 FIX_LI_PCIB, /* Lithium PCI Bridge B */
72 #ifdef CONFIG_X86_F00F_BUG
73 FIX_F00F_IDT, /* Virtual mapping for IDT */
75 #ifdef CONFIG_X86_CYCLONE_TIMER
76 FIX_CYCLONE_TIMER, /*cyclone timer register*/
79 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */
80 FIX_KMAP_END = FIX_KMAP_BEGIN+(KM_TYPE_NR*NR_CPUS)-1,
82 #ifdef CONFIG_PCI_MMCONFIG
85 #ifdef CONFIG_PARAVIRT
88 __end_of_permanent_fixed_addresses,
90 * 256 temporary boot-time mappings, used by early_ioremap(),
91 * before ioremap() is functional.
93 * We round it up to the next 256 pages boundary so that we
94 * can have a single pgd entry and a single pte table:
96 #define NR_FIX_BTMAPS 64
97 #define FIX_BTMAPS_NESTING 4
98 FIX_BTMAP_END = __end_of_permanent_fixed_addresses + 256 -
99 (__end_of_permanent_fixed_addresses & 255),
100 FIX_BTMAP_BEGIN = FIX_BTMAP_END + NR_FIX_BTMAPS*FIX_BTMAPS_NESTING - 1,
104 FIX_ACPI_END = FIX_ACPI_BEGIN + FIX_ACPI_PAGES - 1,
106 #ifdef CONFIG_PROVIDE_OHCI1394_DMA_INIT
109 __end_of_fixed_addresses
112 extern void reserve_top_address(unsigned long reserve);
115 #define FIXADDR_TOP ((unsigned long)__FIXADDR_TOP)
117 #define __FIXADDR_SIZE (__end_of_permanent_fixed_addresses << PAGE_SHIFT)
118 #define __FIXADDR_BOOT_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
119 #define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE)
120 #define FIXADDR_BOOT_START (FIXADDR_TOP - __FIXADDR_BOOT_SIZE)
122 #endif /* !__ASSEMBLY__ */