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 /* 27 * Here we define all the compile-time 'special' virtual 28 * addresses. The point is to have a constant address at 29 * compile time, but to set the physical address only 30 * in the boot process. We allocate these special addresses 31 * from the end of virtual memory (0xfffff000) backwards. 32 * Also this lets us do fail-safe vmalloc(), we 33 * can guarantee that these special addresses and 34 * vmalloc()-ed addresses never overlap. 35 * 36 * these 'compile-time allocated' memory buffers are 37 * fixed-size 4k pages. (or larger if used with an increment 38 * highger than 1) use fixmap_set(idx,phys) to associate 39 * physical memory with fixmap indices. 40 * 41 * TLB entries of such buffers will not be flushed across 42 * task switches. 43 */ 44 enum fixed_addresses { 45 FIX_HOLE, 46 #ifdef CONFIG_PPC32 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+(ALIGN(SZ_128K, PAGE_SIZE)/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_MAX_IDX * 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 #ifdef CONFIG_PPC_83xx 62 /* For IMMR we need an aligned 2M area */ 63 #define FIX_IMMR_SIZE (SZ_2M / PAGE_SIZE) 64 FIX_IMMR_START, 65 FIX_IMMR_BASE = __ALIGN_MASK(FIX_IMMR_START, FIX_IMMR_SIZE - 1) - 1 + 66 FIX_IMMR_SIZE, 67 #endif 68 /* FIX_PCIE_MCFG, */ 69 #endif /* CONFIG_PPC32 */ 70 __end_of_permanent_fixed_addresses, 71 72 #define NR_FIX_BTMAPS (SZ_256K / PAGE_SIZE) 73 #define FIX_BTMAPS_SLOTS 16 74 #define TOTAL_FIX_BTMAPS (NR_FIX_BTMAPS * FIX_BTMAPS_SLOTS) 75 76 FIX_BTMAP_END = __end_of_permanent_fixed_addresses, 77 FIX_BTMAP_BEGIN = FIX_BTMAP_END + TOTAL_FIX_BTMAPS - 1, 78 __end_of_fixed_addresses 79 }; 80 81 #define __FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) 82 #define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE) 83 84 #define FIXMAP_ALIGNED_SIZE (ALIGN(FIXADDR_TOP, PGDIR_SIZE) - \ 85 ALIGN_DOWN(FIXADDR_START, PGDIR_SIZE)) 86 #define FIXMAP_PTE_SIZE (FIXMAP_ALIGNED_SIZE / PGDIR_SIZE * PTE_TABLE_SIZE) 87 88 #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG 89 #define FIXMAP_PAGE_IO PAGE_KERNEL_NCG 90 91 #include <asm-generic/fixmap.h> 92 93 static inline void __set_fixmap(enum fixed_addresses idx, 94 phys_addr_t phys, pgprot_t flags) 95 { 96 BUILD_BUG_ON(IS_ENABLED(CONFIG_PPC64) && __FIXADDR_SIZE > FIXADDR_SIZE); 97 98 if (__builtin_constant_p(idx)) 99 BUILD_BUG_ON(idx >= __end_of_fixed_addresses); 100 else if (WARN_ON(idx >= __end_of_fixed_addresses)) 101 return; 102 if (pgprot_val(flags)) 103 map_kernel_page(__fix_to_virt(idx), phys, flags); 104 else 105 unmap_kernel_page(__fix_to_virt(idx)); 106 } 107 108 #define __early_set_fixmap __set_fixmap 109 110 #ifdef CONFIG_PPC_8xx 111 #define VIRT_IMMR_BASE (__fix_to_virt(FIX_IMMR_BASE)) 112 #endif 113 114 #endif /* !__ASSEMBLY__ */ 115 #endif 116