arch/hexagon/include/asm/mem-layout.h

   1 /*
   2  * Memory layout definitions for the Hexagon architecture
   3  *
   4  * Copyright (c) 2010-2011, Code Aurora Forum. All rights reserved.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2 and
   8  * only version 2 as published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  18  * 02110-1301, USA.
  19  */
  20
  21 #ifndef _ASM_HEXAGON_MEM_LAYOUT_H
  22 #define _ASM_HEXAGON_MEM_LAYOUT_H
  23
  24 #include <linux/const.h>
  25
  26 /*
  27  * Have to do this for ginormous numbers, else they get printed as
  28  * negative numbers, which the linker no likey when you try to
  29  * assign it to the location counter.
  30  */
  31
  32 #define PAGE_OFFSET                     _AC(0xc0000000, UL)
  33
  34 /*
  35  * LOAD_ADDRESS is the physical/linear address of where in memory
  36  * the kernel gets loaded. The 12 least significant bits must be zero (0)
  37  * due to limitations on setting the EVB
  38  *
  39  */
  40
  41 #ifndef LOAD_ADDRESS
  42 #define LOAD_ADDRESS                    0x00000000
  43 #endif
  44
  45 #define TASK_SIZE                       (PAGE_OFFSET)
  46
  47 /*  not sure how these are used yet  */
  48 #define STACK_TOP                       TASK_SIZE
  49 #define STACK_TOP_MAX                   TASK_SIZE
  50
  51 #ifndef __ASSEMBLY__
  52 enum fixed_addresses {
  53         FIX_KMAP_BEGIN,
  54         FIX_KMAP_END,  /*  check for per-cpuism  */
  55         __end_of_fixed_addresses
  56 };
  57
  58 #define MIN_KERNEL_SEG 0x300   /* From 0xc0000000 */
  59 extern int max_kernel_seg;
  60
  61 /*
  62  * Start of vmalloc virtual address space for kernel;
  63  * supposed to be based on the amount of physical memory available
  64  */
  65
  66 #define VMALLOC_START (PAGE_OFFSET + VMALLOC_OFFSET + \
  67         (unsigned long)high_memory)
  68
  69 /* Gap between physical ram and vmalloc space for guard purposes. */
  70 #define VMALLOC_OFFSET PAGE_SIZE
  71
  72 /*
  73  * Create the space between VMALLOC_START and FIXADDR_TOP backwards
  74  * from the ... "top".
  75  *
  76  * Permanent IO mappings will live at 0xfexx_xxxx
  77  * Hypervisor occupies the last 16MB page at 0xffxxxxxx
  78  */
  79
  80 #define FIXADDR_TOP     0xfe000000
  81 #define FIXADDR_SIZE    (__end_of_fixed_addresses << PAGE_SHIFT)
  82 #define FIXADDR_START   (FIXADDR_TOP - FIXADDR_SIZE)
  83
  84 /*
  85  * "permanent kernel mappings", defined as long-lasting mappings of
  86  * high-memory page frames into the kernel address space.
  87  */
  88
  89 #define LAST_PKMAP      PTRS_PER_PTE
  90 #define LAST_PKMAP_MASK (LAST_PKMAP - 1)
  91 #define PKMAP_NR(virt)  ((virt - PKMAP_BASE) >> PAGE_SHIFT)
  92 #define PKMAP_ADDR(nr)  (PKMAP_BASE + ((nr) << PAGE_SHIFT))
  93
  94 /*
  95  * To the "left" of the fixed map space is the kmap space
  96  *
  97  * "Permanent Kernel Mappings"; fancy (or less fancy) PTE table
  98  * that looks like it's actually walked.
  99  * Need to check the alignment/shift usage; some archs use
 100  * PMD_MASK on this value
 101  */
 102 #define PKMAP_BASE (FIXADDR_START-PAGE_SIZE*LAST_PKMAP)
 103
 104 /*
 105  * 2 pages of guard gap between where vmalloc area ends
 106  * and pkmap_base begins.
 107  */
 108 #define VMALLOC_END (PKMAP_BASE-PAGE_SIZE*2)
 109 #endif /*  !__ASSEMBLY__  */
 110
 111
 112 #endif /* _ASM_HEXAGON_MEM_LAYOUT_H */