xref: /openbmc/u-boot/arch/xtensa/cpu/u-boot.lds (revision 12308b12)
1/* SPDX-License-Identifier: GPL-2.0+ */
2/*
3 * (C) Copyright 2008 - 2013 Tensilica, Inc.
4 * (C) Copyright 2014 - 2016 Cadence Design Systems Inc.
5 */
6
7#include <config.h>
8#include <asm/ldscript.h>
9#include <asm/arch/core.h>
10#include <asm/addrspace.h>
11#include <asm-offsets.h>
12
13OUTPUT_ARCH(xtensa)
14ENTRY(_start)
15
16/*
17 * U-Boot resets from SYSROM and unpacks itself from a ROM store to RAM.
18 * The reset vector is usually near the base of SYSROM and has room
19 * above it for the ROM store into which the rest of U-Boot is packed.
20 * The ROM store also needs to be above any other vectors that are in ROM.
21 * If a core has its vectors near the top of ROM, this must be edited.
22 *
23 * Note that to run C code out of ROM, the processor would have to support
24 * 'relocatable' exception vectors and provide a scratch memory for the
25 * initial stack. Not all Xtensa processor configurations support that, so
26 * we can simplify the boot process and unpack U-Boot to RAM immediately.
27 * This, however, requires that memory have been initialized throug some
28 * other means (serial ROM, for example) or are initialized early (requiring
29 * an assembler function. See start.S for more details)
30 */
31
32SECTIONS
33{
34  . = + SIZEOF_HEADERS;
35  SECTION_ResetVector(XCHAL_RESET_VECTOR_VADDR, LMA_EQ_VMA)
36
37  .reloc_table ALIGN(4) : FOLLOWING(.ResetVector.text)
38  {
39    __reloc_table_start = ABSOLUTE(.);
40#if XCHAL_HAVE_WINDOWED
41    RELOCATE2(WindowVectors,text);
42#endif
43    RELOCATE2(KernelExceptionVector,literal);
44    RELOCATE2(KernelExceptionVector,text);
45    RELOCATE2(UserExceptionVector,literal);
46    RELOCATE2(UserExceptionVector,text);
47    RELOCATE2(DoubleExceptionVector,literal);
48    RELOCATE2(DoubleExceptionVector,text);
49    RELOCATE1(text);
50    RELOCATE1(rodata);
51    RELOCATE1(data);
52    RELOCATE1(u_boot_list);
53    __reloc_table_end = ABSOLUTE(.);
54  }
55
56#if XCHAL_HAVE_WINDOWED
57  SECTION_VECTOR(WindowVectors,text,XCHAL_WINDOW_VECTORS_VADDR,
58		 FOLLOWING(.reloc_table))
59  SECTION_VECTOR(KernelExceptionVector,literal,XCHAL_KERNEL_VECTOR_VADDR-8,
60		 FOLLOWING(.WindowVectors.text))
61#else
62  SECTION_VECTOR(KernelExceptionVector,literal,XCHAL_KERNEL_VECTOR_VADDR-8,
63		 FOLLOWING(.reloc_table))
64#endif
65  SECTION_VECTOR(KernelExceptionVector,text,XCHAL_KERNEL_VECTOR_VADDR,
66		 FOLLOWING(.KernelExceptionVector.literal))
67  SECTION_VECTOR(UserExceptionVector,literal,XCHAL_USER_VECTOR_VADDR-8,
68		 FOLLOWING(.KernelExceptionVector.text))
69  SECTION_VECTOR(UserExceptionVector,text,XCHAL_USER_VECTOR_VADDR,
70		 FOLLOWING(.UserExceptionVector.literal))
71  SECTION_VECTOR(DoubleExceptionVector,literal,XCHAL_DOUBLEEXC_VECTOR_VADDR-8,
72		 FOLLOWING(.UserExceptionVector.text))
73  SECTION_VECTOR(DoubleExceptionVector,text,XCHAL_DOUBLEEXC_VECTOR_VADDR,
74		 FOLLOWING(.DoubleExceptionVector.literal))
75
76  __monitor_start = XTENSA_SYS_TEXT_ADDR;
77
78  SECTION_text(XTENSA_SYS_TEXT_ADDR, FOLLOWING(.DoubleExceptionVector.text))
79  SECTION_rodata(ALIGN(16), FOLLOWING(.text))
80  SECTION_u_boot_list(ALIGN(16), FOLLOWING(.rodata))
81  SECTION_data(ALIGN(16), FOLLOWING(.u_boot_list))
82
83  __reloc_end = .;
84  __init_end = .;
85
86  SECTION_bss(__init_end (OVERLAY),)
87
88  __monitor_end = .;
89
90  /*
91   * On many Xtensa boards a region of RAM may be mapped to the ROM address
92   * space to facilitate on-chip-debug, and U-Boot must fit with that region.
93   * The config variables CONFIG_SYS_MONITOR_* define the region.
94   * If U-Boot extends beyond this region it will appear discontiguous in the
95   * address space and is in danger of overwriting itself during unpacking
96   * ("relocation").
97   * This causes U-Boot to crash in a way that is difficult to debug. On some
98   * boards (such as xtav60) the region is small enough that U-Boot will not
99   * fit if compiled entirely with -O0 (a common scenario). To avoid a lengthy
100   * debugging session when this happens, ensure a link-time error occurs.
101   *
102   */
103
104   ASSERT(__monitor_end - __monitor_start <= CONFIG_SYS_MONITOR_LEN,
105          "U-Boot ROM image is too large. Check optimization level.")
106
107  SECTION_xtensa
108  SECTION_debug
109
110  /DISCARD/ : { *(.dynstr*) }
111  /DISCARD/ : { *(.hash*) }
112  /DISCARD/ : { *(.interp) }
113  /DISCARD/ : { *(.got*) }
114  /DISCARD/ : { *(.dynsym) }
115}
116