1 /* SPDX-License-Identifier: GPL-2.0-only */ 2 /* 3 * Memory layout definitions for the Hexagon architecture 4 * 5 * Copyright (c) 2010-2013, The Linux Foundation. All rights reserved. 6 */ 7 8 #ifndef _ASM_HEXAGON_MEM_LAYOUT_H 9 #define _ASM_HEXAGON_MEM_LAYOUT_H 10 11 #include <linux/const.h> 12 13 /* 14 * Have to do this for ginormous numbers, else they get printed as 15 * negative numbers, which the linker no likey when you try to 16 * assign it to the location counter. 17 */ 18 19 #define PAGE_OFFSET _AC(0xc0000000, UL) 20 21 /* 22 * Compiling for a platform that needs a crazy physical offset 23 * (like if the memory starts at 1GB and up) means we need 24 * an actual PHYS_OFFSET. Should be set up in head.S. 25 */ 26 27 #ifdef CONFIG_HEXAGON_PHYS_OFFSET 28 #ifndef __ASSEMBLY__ 29 extern unsigned long __phys_offset; 30 #endif 31 #define PHYS_OFFSET __phys_offset 32 #endif 33 34 #ifndef PHYS_OFFSET 35 #define PHYS_OFFSET 0 36 #endif 37 38 #define PHYS_PFN_OFFSET (PHYS_OFFSET >> PAGE_SHIFT) 39 #define ARCH_PFN_OFFSET PHYS_PFN_OFFSET 40 41 #define TASK_SIZE (PAGE_OFFSET) 42 43 /* not sure how these are used yet */ 44 #define STACK_TOP TASK_SIZE 45 #define STACK_TOP_MAX TASK_SIZE 46 47 #ifndef __ASSEMBLY__ 48 enum fixed_addresses { 49 FIX_KMAP_BEGIN, 50 FIX_KMAP_END, /* check for per-cpuism */ 51 __end_of_fixed_addresses 52 }; 53 54 #define MIN_KERNEL_SEG (PAGE_OFFSET >> PGDIR_SHIFT) /* L1 shift is 22 bits */ 55 extern int max_kernel_seg; 56 57 /* 58 * Start of vmalloc virtual address space for kernel; 59 * supposed to be based on the amount of physical memory available 60 */ 61 62 #define VMALLOC_START ((unsigned long) __va(high_memory + VMALLOC_OFFSET)) 63 64 /* Gap between physical ram and vmalloc space for guard purposes. */ 65 #define VMALLOC_OFFSET PAGE_SIZE 66 67 /* 68 * Create the space between VMALLOC_START and FIXADDR_TOP backwards 69 * from the ... "top". 70 * 71 * Permanent IO mappings will live at 0xfexx_xxxx 72 * Hypervisor occupies the last 16MB page at 0xffxxxxxx 73 */ 74 75 #define FIXADDR_TOP 0xfe000000 76 #define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT) 77 #define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE) 78 79 /* 80 * "permanent kernel mappings", defined as long-lasting mappings of 81 * high-memory page frames into the kernel address space. 82 */ 83 84 #define LAST_PKMAP PTRS_PER_PTE 85 #define LAST_PKMAP_MASK (LAST_PKMAP - 1) 86 #define PKMAP_NR(virt) ((virt - PKMAP_BASE) >> PAGE_SHIFT) 87 #define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT)) 88 89 /* 90 * To the "left" of the fixed map space is the kmap space 91 * 92 * "Permanent Kernel Mappings"; fancy (or less fancy) PTE table 93 * that looks like it's actually walked. 94 * Need to check the alignment/shift usage; some archs use 95 * PMD_MASK on this value 96 */ 97 #define PKMAP_BASE (FIXADDR_START-PAGE_SIZE*LAST_PKMAP) 98 99 /* 100 * 2 pages of guard gap between where vmalloc area ends 101 * and pkmap_base begins. 102 */ 103 #define VMALLOC_END (PKMAP_BASE-PAGE_SIZE*2) 104 #endif /* !__ASSEMBLY__ */ 105 106 107 #endif /* _ASM_HEXAGON_MEM_LAYOUT_H */ 108