/* * fixmap.h: compile-time virtual memory allocation * * This file is subject to the terms and conditions of the GNU General Public * License.  See the file "COPYING" in the main directory of this archive * for more details. * * Copyright (C) 1998 Ingo Molnar * * Copyright 2008 Freescale Semiconductor Inc. *   Port to powerpc added by Kumar Gala * * Copyright 2011 Michal Simek <monstr@monstr.eu> * Copyright 2011 PetaLogix Qld Pty Ltd *   Port to Microblaze */ #ifndef _ASM_FIXMAP_H#define _ASM_FIXMAP_H #ifndef __ASSEMBLY__#include <linux/kernel.h>#include <asm/page.h>#ifdef CONFIG_HIGHMEM#include <linux/threads.h>#include <asm/kmap_types.h>#endif #define FIXADDR_TOP	((unsigned long)(-PAGE_SIZE)) /* * Here we define all the compile-time 'special' virtual * addresses. The point is to have a constant address at * compile time, but to set the physical address only * in the boot process. We allocate these special addresses * from the end of virtual memory (0xfffff000) backwards. * Also this lets us do fail-safe vmalloc(), we * can guarantee that these special addresses and * vmalloc()-ed addresses never overlap. * * these 'compile-time allocated' memory buffers are * fixed-size 4k pages. (or larger if used with an increment * highger than 1) use fixmap_set(idx,phys) to associate * physical memory with fixmap indices. * * TLB entries of such buffers will not be flushed across * task switches. */enum fixed_addresses {	FIX_HOLE,#ifdef CONFIG_HIGHMEM	FIX_KMAP_BEGIN,	/* reserved pte's for temporary kernel mappings */	FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * num_possible_cpus()) - 1,#endif	__end_of_fixed_addresses}; extern void __set_fixmap(enum fixed_addresses idx,					phys_addr_t phys, pgprot_t flags); #define set_fixmap(idx, phys) \		__set_fixmap(idx, phys, PAGE_KERNEL)/* * Some hardware wants to get fixmapped without caching. */#define set_fixmap_nocache(idx, phys) \		__set_fixmap(idx, phys, PAGE_KERNEL_CI) #define clear_fixmap(idx) \		__set_fixmap(idx, 0, __pgprot(0)) #define __FIXADDR_SIZE	(__end_of_fixed_addresses << PAGE_SHIFT)#define FIXADDR_START		(FIXADDR_TOP - __FIXADDR_SIZE) #define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << PAGE_SHIFT))#define __virt_to_fix(x)	((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT) extern void __this_fixmap_does_not_exist(void); /* * 'index to address' translation. If anyone tries to use the idx * directly without tranlation, we catch the bug with a NULL-deference * kernel oops. Illegal ranges of incoming indices are caught too. */static __always_inline unsigned long fix_to_virt(const unsigned int idx){	/*	 * this branch gets completely eliminated after inlining,	 * except when someone tries to use fixaddr indices in an	 * illegal way. (such as mixing up address types or using	 * out-of-range indices).	 *	 * If it doesn't get removed, the linker will complain	 * loudly with a reasonably clear error message..	 */	if (idx >= __end_of_fixed_addresses)		__this_fixmap_does_not_exist(); 	return __fix_to_virt(idx);} static inline unsigned long virt_to_fix(const unsigned long vaddr){	BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);	return __virt_to_fix(vaddr);} #endif /* !__ASSEMBLY__ */#endif