| Kyle Swenson | 8d8f654 | 2021-03-15 11:02:55 -0600 | [diff] [blame^] | 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/kernel.h> |
| 19 | #include <asm/page.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 | /* FIX_PCIE_MCFG, */ |
| 55 | __end_of_fixed_addresses |
| 56 | }; |
| 57 | |
| 58 | extern void __set_fixmap (enum fixed_addresses idx, |
| 59 | phys_addr_t phys, pgprot_t flags); |
| 60 | |
| 61 | #define __FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) |
| 62 | #define FIXADDR_START (FIXADDR_TOP - __FIXADDR_SIZE) |
| 63 | |
| 64 | #define FIXMAP_PAGE_NOCACHE PAGE_KERNEL_NCG |
| 65 | |
| 66 | #include <asm-generic/fixmap.h> |
| 67 | |
| 68 | #endif /* !__ASSEMBLY__ */ |
| 69 | #endif |