linux/arch/arm/kernel/vmlinux-xip.lds.S
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   1/* SPDX-License-Identifier: GPL-2.0 */
   2/* ld script to make ARM Linux kernel
   3 * taken from the i386 version by Russell King
   4 * Written by Martin Mares <mj@atrey.karlin.mff.cuni.cz>
   5 */
   6
   7/* No __ro_after_init data in the .rodata section - which will always be ro */
   8#define RO_AFTER_INIT_DATA
   9
  10#include <linux/sizes.h>
  11
  12#include <asm-generic/vmlinux.lds.h>
  13#include <asm/cache.h>
  14#include <asm/thread_info.h>
  15#include <asm/memory.h>
  16#include <asm/mpu.h>
  17#include <asm/page.h>
  18
  19#include "vmlinux.lds.h"
  20
  21OUTPUT_ARCH(arm)
  22ENTRY(stext)
  23
  24#ifndef __ARMEB__
  25jiffies = jiffies_64;
  26#else
  27jiffies = jiffies_64 + 4;
  28#endif
  29
  30SECTIONS
  31{
  32        /*
  33         * XXX: The linker does not define how output sections are
  34         * assigned to input sections when there are multiple statements
  35         * matching the same input section name.  There is no documented
  36         * order of matching.
  37         *
  38         * unwind exit sections must be discarded before the rest of the
  39         * unwind sections get included.
  40         */
  41        /DISCARD/ : {
  42                ARM_DISCARD
  43                *(.alt.smp.init)
  44                *(.pv_table)
  45        }
  46
  47        . = XIP_VIRT_ADDR(CONFIG_XIP_PHYS_ADDR);
  48        _xiprom = .;                    /* XIP ROM area to be mapped */
  49
  50        .head.text : {
  51                _text = .;
  52                HEAD_TEXT
  53        }
  54
  55        .text : {                       /* Real text segment            */
  56                _stext = .;             /* Text and read-only data      */
  57                ARM_TEXT
  58        }
  59
  60        RO_DATA(PAGE_SIZE)
  61
  62        . = ALIGN(4);
  63        __ex_table : AT(ADDR(__ex_table) - LOAD_OFFSET) {
  64                __start___ex_table = .;
  65                ARM_MMU_KEEP(*(__ex_table))
  66                __stop___ex_table = .;
  67        }
  68
  69#ifdef CONFIG_ARM_UNWIND
  70        ARM_UNWIND_SECTIONS
  71#endif
  72
  73        _etext = .;                     /* End of text and rodata section */
  74
  75        ARM_VECTORS
  76        INIT_TEXT_SECTION(8)
  77        .exit.text : {
  78                ARM_EXIT_KEEP(EXIT_TEXT)
  79        }
  80        .init.proc.info : {
  81                ARM_CPU_DISCARD(PROC_INFO)
  82        }
  83        .init.arch.info : {
  84                __arch_info_begin = .;
  85                *(.arch.info.init)
  86                __arch_info_end = .;
  87        }
  88        .init.tagtable : {
  89                __tagtable_begin = .;
  90                *(.taglist.init)
  91                __tagtable_end = .;
  92        }
  93        .init.rodata : {
  94                INIT_SETUP(16)
  95                INIT_CALLS
  96                CON_INITCALL
  97                INIT_RAM_FS
  98        }
  99
 100#ifdef CONFIG_ARM_MPU
 101        . = ALIGN(SZ_128K);
 102#endif
 103        _exiprom = .;                   /* End of XIP ROM area */
 104
 105/*
 106 * From this point, stuff is considered writable and will be copied to RAM
 107 */
 108        __data_loc = ALIGN(4);          /* location in file */
 109        . = PAGE_OFFSET + TEXT_OFFSET;  /* location in memory */
 110#undef LOAD_OFFSET
 111#define LOAD_OFFSET (PAGE_OFFSET + TEXT_OFFSET - __data_loc)
 112
 113        . = ALIGN(THREAD_SIZE);
 114        _sdata = .;
 115        RW_DATA(L1_CACHE_BYTES, PAGE_SIZE, THREAD_SIZE)
 116        .data.ro_after_init : AT(ADDR(.data.ro_after_init) - LOAD_OFFSET) {
 117                *(.data..ro_after_init)
 118        }
 119        _edata = .;
 120
 121        . = ALIGN(PAGE_SIZE);
 122        __init_begin = .;
 123        .init.data : AT(ADDR(.init.data) - LOAD_OFFSET) {
 124                INIT_DATA
 125        }
 126        .exit.data : AT(ADDR(.exit.data) - LOAD_OFFSET) {
 127                ARM_EXIT_KEEP(EXIT_DATA)
 128        }
 129#ifdef CONFIG_SMP
 130        PERCPU_SECTION(L1_CACHE_BYTES)
 131#endif
 132
 133#ifdef CONFIG_HAVE_TCM
 134        ARM_TCM
 135#endif
 136
 137        /*
 138         * End of copied data. We need a dummy section to get its LMA.
 139         * Also located before final ALIGN() as trailing padding is not stored
 140         * in the resulting binary file and useless to copy.
 141         */
 142        .data.endmark : AT(ADDR(.data.endmark) - LOAD_OFFSET) { }
 143        _edata_loc = LOADADDR(.data.endmark);
 144
 145        . = ALIGN(PAGE_SIZE);
 146        __init_end = .;
 147
 148        BSS_SECTION(0, 0, 8)
 149#ifdef CONFIG_ARM_MPU
 150        . = ALIGN(PMSAv8_MINALIGN);
 151#endif
 152        _end = .;
 153
 154        STABS_DEBUG
 155}
 156
 157/*
 158 * These must never be empty
 159 * If you have to comment these two assert statements out, your
 160 * binutils is too old (for other reasons as well)
 161 */
 162ASSERT((__proc_info_end - __proc_info_begin), "missing CPU support")
 163ASSERT((__arch_info_end - __arch_info_begin), "no machine record defined")
 164
 165#ifdef CONFIG_XIP_DEFLATED_DATA
 166/*
 167 * The .bss is used as a stack area for __inflate_kernel_data() whose stack
 168 * frame is 9568 bytes. Make sure it has extra room left.
 169 */
 170ASSERT((_end - __bss_start) >= 12288, ".bss too small for CONFIG_XIP_DEFLATED_DATA")
 171#endif
 172
 173#ifdef CONFIG_ARM_MPU
 174/*
 175 * Due to PMSAv7 restriction on base address and size we have to
 176 * enforce minimal alignment restrictions. It was seen that weaker
 177 * alignment restriction on _xiprom will likely force XIP address
 178 * space spawns multiple MPU regions thus it is likely we run in
 179 * situation when we are reprogramming MPU region we run on with
 180 * something which doesn't cover reprogramming code itself, so as soon
 181 * as we update MPU settings we'd immediately try to execute straight
 182 * from background region which is XN.
 183 * It seem that alignment in 1M should suit most users.
 184 * _exiprom is aligned as 1/8 of 1M so can be covered by subregion
 185 * disable
 186 */
 187ASSERT(!(_xiprom & (SZ_1M - 1)), "XIP start address may cause MPU programming issues")
 188ASSERT(!(_exiprom & (SZ_128K - 1)), "XIP end address may cause MPU programming issues")
 189#endif
 190