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 <linux/sizes.h> 19 #include <linux/pgtable.h> 20 #include <asm/page.h> 21 #ifdef CONFIG_HIGHMEM 22 #include <linux/threads.h> 23 #include <asm/kmap_size.h> 24 #endif 25 26 #ifdef CONFIG_PPC64 27 #define FIXADDR_TOP (IOREMAP_END + FIXADDR_SIZE) 28 #else 29 #define FIXADDR_SIZE 0 30 #ifdef CONFIG_KASAN 31 #include <asm/kasan.h> 32 #define FIXADDR_TOP (KASAN_SHADOW_START - PAGE_SIZE) 33 #else 34 #define FIXADDR_TOP ((unsigned long)(-PAGE_SIZE)) 35 #endif 36 #endif 37 38 /* 39 * Here we define all the compile-time 'special' virtual 40 * addresses. The point is to have a constant address at 41 * compile time, but to set the physical address only 42 * in the boot process. We allocate these special addresses 43 * from the end of virtual memory (0xfffff000) backwards. 44 * Also this lets us do fail-safe vmalloc(), we 45 * can guarantee that these special addresses and 46 * vmalloc()-ed addresses never overlap. 47 * 48 * these 'compile-time allocated' memory buffers are 49 * fixed-size 4k pages. (or larger if used with an increment 50 * highger than 1) use fixmap_set(idx,phys) to associate 51 * physical memory with fixmap indices. 52 * 53 * TLB entries of such buffers will not be flushed across 54 * task switches. 55 */ 56 enum fixed_addresses { 57 FIX_HOLE, 58 #ifdef CONFIG_PPC32 59 /* reserve the top 128K for early debugging purposes */ 60 FIX_EARLY_DEBUG_TOP = FIX_HOLE, 61 FIX_EARLY_DEBUG_BASE = FIX_EARLY_DEBUG_TOP+(ALIGN(SZ_128K, PAGE_SIZE)/PAGE_SIZE)-1, 62 #ifdef CONFIG_HIGHMEM 63 FIX_KMAP_BEGIN, /* reserved pte's for temporary kernel mappings */ 64 FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_MAX_IDX * NR_CPUS) - 1, 65 #endif 66 #ifdef CONFIG_PPC_8xx 67 /* For IMMR we need an aligned 512K area */ 68 #define FIX_IMMR_SIZE (512 * 1024 / PAGE_SIZE) 69 FIX_IMMR_START, 70 FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 + 71 FIX_IMMR_SIZE, 72 #endif 73 #ifdef CONFIG_PPC_83xx 74 /* For IMMR we need an aligned 2M area */ 75 #define FIX_IMMR_SIZE (SZ_2M / PAGE_SIZE) 76 FIX_IMMR_START, 77 FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 + 78 FIX_IMMR_SIZE, 79 #endif 80 /* FIX_PCIE_MCFG, */ 81 #endif /* CONFIG_PPC32 */ 82 __end_of_permanent_fixed_addresses, 83 84 #define NR_FIX_BTMAPS (SZ_256K / PAGE_SIZE) 85 #define FIX_BTMAPS_SLOTS 16 86 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 87 88 FIX_BTMAP_END = __end_of_permanent_fixed_addresses, 89 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 90 __end_of_fixed_addresses 91 }; 92 93 #define __FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) 94 #define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE) 95 96 #define FIXMAP_ALIGNED_SIZE (ALIGN(FIXADDR_TOP, PGDIR_SIZE) - \ 97 ALIGN_DOWN(FIXADDR_START, PGDIR_SIZE)) 98 #define FIXMAP_PTE_SIZE (FIXMAP_ALIGNED_SIZE / PGDIR_SIZE * PTE_TABLE_SIZE) 99 100 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG 101 #define FIXMAP_PAGE_IO PAGE_KERNEL_NCG 102 103 #include <asm-generic/fixmap.h> 104 105 static inline void __set_fixmap(enum fixed_addresses idx, 106 phys_addr_t phys, pgprot_t flags) 107 { 108 BUILD_BUG_ON(IS_ENABLED(CONFIG_PPC64) && __FIXADDR_SIZE > FIXADDR_SIZE); 109 110 if (__builtin_constant_p(idx)) 111 BUILD_BUG_ON(idx >= __end_of_fixed_addresses); 112 else if (WARN_ON(idx >= __end_of_fixed_addresses)) 113 return; 114 115 map_kernel_page(__fix_to_virt(idx), phys, flags); 116 } 117 118 #define __early_set_fixmap __set_fixmap 119 120 #endif /* !__ASSEMBLY__ */ 121 #endif 122