Aaron Durbin | ad93552 | 2012-12-24 14:28:37 -0600 | [diff] [blame] | 1 | OUTPUT_FORMAT("elf32-i386", "elf32-i386", "elf32-i386") |
| 2 | OUTPUT_ARCH(i386) |
| 3 | |
| 4 | /* |
| 5 | * This linker script is used to link rmodules (relocatable modules). It |
| 6 | * links at zero so that relocation fixups are easy when placing the binaries |
| 7 | * anywhere in the address space. |
| 8 | * |
| 9 | * NOTE: The program's loadable sections (text, module_params, and data) are |
| 10 | * packed into the flat blob using the AT directive. The rmodule loader assumes |
| 11 | * the entire program resides in one contiguous address space. Therefore, |
| 12 | * alignment for a given section (if required) needs to be done at the end of |
| 13 | * the preceeding section. e.g. if the data section should be aligned to an 8 |
| 14 | * byte address the text section should have ALIGN(8) at the end of its section. |
| 15 | * Otherwise there won't be a consistent mapping between the flat blob and the |
| 16 | * loaded program. |
| 17 | */ |
| 18 | |
| 19 | BASE_ADDRESS = 0x00000; |
| 20 | |
| 21 | SECTIONS |
| 22 | { |
| 23 | . = BASE_ADDRESS; |
| 24 | |
| 25 | .header : AT (0) { |
| 26 | *(.module_header); |
| 27 | . = ALIGN(8); |
| 28 | } |
| 29 | |
| 30 | /* Align the start of the module program to a large enough alignment |
| 31 | * so that any data in the program with an alignement property is met. |
| 32 | * Essentially, this alignment is the maximum possible data alignment |
| 33 | * property a program can have. */ |
| 34 | . = ALIGN(4096); |
| 35 | _module_link_start_addr = .; |
| 36 | _payload_begin_offset = LOADADDR(.header) + SIZEOF(.header); |
| 37 | |
| 38 | .text : AT (_payload_begin_offset) { |
| 39 | /* C code of the module. */ |
Aaron Durbin | d23e292e | 2013-03-22 19:55:35 -0500 | [diff] [blame^] | 40 | *(.textfirst); |
Aaron Durbin | ad93552 | 2012-12-24 14:28:37 -0600 | [diff] [blame] | 41 | *(.text); |
| 42 | *(.text.*); |
| 43 | /* C read-only data. */ |
| 44 | . = ALIGN(16); |
Aaron Durbin | f7c6d48 | 2013-02-06 15:47:31 -0600 | [diff] [blame] | 45 | |
Aaron Durbin | d23e292e | 2013-03-22 19:55:35 -0500 | [diff] [blame^] | 46 | __CTOR_LIST__ = .; |
| 47 | *(.ctors); |
| 48 | LONG(0); |
| 49 | __CTOR_END__ = .; |
| 50 | |
Aaron Durbin | f7c6d48 | 2013-02-06 15:47:31 -0600 | [diff] [blame] | 51 | /* The driver sections are to allow linking coreboot's |
| 52 | * ramstage with the rmodule linker. Any changes made in |
| 53 | * coreboot_ram.ld should be made here as well. */ |
| 54 | console_drivers = .; |
| 55 | *(.rodata.console_drivers) |
| 56 | econsole_drivers = . ; |
| 57 | . = ALIGN(4); |
| 58 | pci_drivers = . ; |
| 59 | *(.rodata.pci_driver) |
| 60 | epci_drivers = . ; |
| 61 | cpu_drivers = . ; |
| 62 | *(.rodata.cpu_driver) |
| 63 | ecpu_drivers = . ; |
| 64 | . = ALIGN(4); |
| 65 | |
Aaron Durbin | ad93552 | 2012-12-24 14:28:37 -0600 | [diff] [blame] | 66 | *(.rodata); |
| 67 | *(.rodata.*); |
| 68 | . = ALIGN(4); |
| 69 | } |
| 70 | |
| 71 | .module_params : AT (LOADADDR(.text) + SIZEOF(.text)) { |
| 72 | /* The parameters section can be used to pass parameters |
| 73 | * to a module, however there has to be an prior agreement |
| 74 | * on how to interpret the parameters. */ |
| 75 | _module_params_begin = .; |
| 76 | *(.module_parameters); |
| 77 | _module_params_end = .; |
| 78 | . = ALIGN(4); |
| 79 | } |
| 80 | |
| 81 | .data : AT (LOADADDR(.module_params) + SIZEOF(.module_params)) { |
| 82 | _sdata = .; |
| 83 | *(.data); |
| 84 | . = ALIGN(4); |
| 85 | _edata = .; |
| 86 | } |
| 87 | |
| 88 | /* _payload_end marks the end of the module's code and data. */ |
| 89 | _payload_end_offset = LOADADDR(.data) + SIZEOF(.data); |
| 90 | |
| 91 | .bss (NOLOAD) : { |
Aaron Durbin | f7c6d48 | 2013-02-06 15:47:31 -0600 | [diff] [blame] | 92 | /* C uninitialized data of the module. */ |
| 93 | _bss = .; |
Aaron Durbin | ad93552 | 2012-12-24 14:28:37 -0600 | [diff] [blame] | 94 | *(.bss); |
| 95 | *(.sbss); |
| 96 | *(COMMON); |
| 97 | . = ALIGN(8); |
Aaron Durbin | f7c6d48 | 2013-02-06 15:47:31 -0600 | [diff] [blame] | 98 | _ebss = .; |
Aaron Durbin | ad93552 | 2012-12-24 14:28:37 -0600 | [diff] [blame] | 99 | |
Aaron Durbin | ad93552 | 2012-12-24 14:28:37 -0600 | [diff] [blame] | 100 | /* |
| 101 | * Place the heap after BSS. The heap size is passed in by |
| 102 | * by way of ld --defsym=__heap_size=<> |
| 103 | */ |
| 104 | _heap = .; |
| 105 | . = . + __heap_size; |
| 106 | _eheap = .; |
| 107 | } |
| 108 | |
| 109 | /* _module_program_size is the total memory used by the program. */ |
| 110 | _module_program_size = _eheap - _module_link_start_addr; |
| 111 | |
Aaron Durbin | f7c6d48 | 2013-02-06 15:47:31 -0600 | [diff] [blame] | 112 | /* coreboot's ramstage uses the _ram_seg and _eram_seg symbols |
| 113 | * for determining its load location. Provide those to help it out. |
| 114 | * It's a nop for any non-ramstage rmodule. */ |
| 115 | _ram_seg = _module_link_start_addr; |
| 116 | _eram_seg = _module_link_start_addr + _module_program_size; |
| 117 | |
Aaron Durbin | ad93552 | 2012-12-24 14:28:37 -0600 | [diff] [blame] | 118 | /* The relocation information is linked on top of the BSS section |
| 119 | * because the BSS section takes no space on disk. The relocation data |
| 120 | * resides directly after the data section in the flat binary. */ |
| 121 | .relocations ADDR(.bss) : AT (_payload_end_offset) { |
| 122 | *(.rel.*); |
| 123 | } |
| 124 | _relocations_begin_offset = LOADADDR(.relocations); |
| 125 | _relocations_end_offset = _relocations_begin_offset + |
| 126 | SIZEOF(.relocations); |
| 127 | |
| 128 | /DISCARD/ : { |
| 129 | /* Drop unnecessary sections. Since these modules are linked |
| 130 | * as shared objects there are dynamic sections. These sections |
| 131 | * aren't needed so drop them. */ |
| 132 | *(.comment); |
| 133 | *(.note); |
| 134 | *(.note.*); |
| 135 | *(.dynamic); |
| 136 | *(.dynsym); |
| 137 | *(.dynstr); |
| 138 | *(.gnu.hash); |
| 139 | *(.eh_frame); |
| 140 | } |
| 141 | } |