Adds support for placing MSP430 code and data into either low memory or high memory.

* msp430/msp430.ld: Delete.
	* msp430/msp430F5438A-l.ld: Delete.
	* msp430/msp430F5438A-s.ld: Delete.
	* msp430/crt_movedata.S: Delete.

	* msp430/Makefile.in (SCRIPTS): Remove msp430.ld.
	(CRT_OBJS): Add crt_move_highdata.o.
	* msp430/memmodel.h (START_CRT_FUNC): New macro.
	(END_CRT_FUNC): New macro.
	(WEAK_DEF): New macro.
	* msp430/crt0.S: Use new macros.
	(move_highdata): New code to initialise the .data section if it is
	held in high memory.

	* msp430/msp430-sim.ld (.data): Add .either.data.
	(.rodata2): Move some read-only data sections here.
	(.text): Add .either.text.
	(.rodata): Add .either.rodata.
	(.bss): Add .either.bss.
	* msp430/msp430xl-sim.ld (MEMORY): Add HIROM.
	(.rodata2): Move some read-only data sections here.
	(.upper.data): New section.  Include notes about how to initialise
	it.
This commit is contained in:
Nick Clifton
2015-05-05 12:45:38 +01:00
committed by Corinna Vinschen
parent 761a123a4f
commit baa681fd38
10 changed files with 462 additions and 793 deletions

View File

@@ -1,27 +1,35 @@
/* Copyright (c) 2013-2014 Red Hat, Inc. All rights reserved.
/* Copyright (c) 2013-2015 Red Hat, Inc. All rights reserved.
This copyrighted material is made available to anyone wishing to use, modify,
copy, or redistribute it subject to the terms and conditions of the BSD
License. This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY expressed or implied, including the implied warranties
of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. A copy of this license
is available at http://www.opensource.org/licenses. Any Red Hat trademarks that
are incorporated in the source code or documentation are not subject to the BSD
License and may only be used or replicated with the express permission of
Red Hat, Inc. */
This copyrighted material is made available to anyone wishing to use,
modify, copy, or redistribute it subject to the terms and conditions of
the BSD License. This program is distributed in the hope that it will be
useful, but WITHOUT ANY WARRANTY expressed or implied, including the
implied warranties of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
A copy of this license is available at http://www.opensource.org/licenses.
/* Default linker script, for large MSP430X executables. */
Any Red Hat trademarks that are incorporated in the source code or
documentation are not subject to the BSD License and may only be used or
replicated with the express permission of Red Hat, Inc. */
/* Example linker script, for large MSP430X executables. */
OUTPUT_ARCH(msp430)
ENTRY(_start)
INCLUDE intr_vectors.ld
/* Note - These memory regions are just examples. Real MSP430 MCUs will have
different varieties and sizes of RAM, ROM and FLASH. Not all devices will
have all of these regions either. Device specific linker scripts are
provided by TI, so this file is intended to be used as a guide and so that
toolchain tests can be run against the simulator. */
MEMORY
{
RAM (w) : ORIGIN = 0x00200, LENGTH = 0x01e00
RAM (rw) : ORIGIN = 0x00200, LENGTH = 0x01e00
ROM (rx) : ORIGIN = 0x02000, LENGTH = 0x0df00
HIFRAM (rxw) : ORIGIN = 0x10000, LENGTH = 0x80000
/* The regions from intr_vectors.ld go here. */
HIFRAM (rw) : ORIGIN = 0x10000, LENGTH = 0x80000
HIROM (rx) : ORIGIN = 0x90000, LENGTH = 0x70000
}
SECTIONS
@@ -31,22 +39,34 @@ SECTIONS
*(.resetvec)
} > VECT31
.upper.rodata :
{
. = ALIGN(2);
*(.upper.rodata.* .upper.rodata)
} > HIFRAM
.rodata :
{
. = ALIGN(2);
*(.plt)
. = ALIGN(2);
*(.lower.rodata.* .lower.rodata)
/* Note: By default we do not have this line:
*(.either.rodata.*) *(.either.rodata)
defined here, or anywhere else in this script. This is deliberate.
The algorithm in the linker that automatically places rodata into
either the .rodata or the .upper.rodata sections relies upon the
fact that the .either.rodata section is not defined, and that the
.upper.rodata section is defined. If the .upper.rodata is not
defined in this script then the line above should be restored so that
code compiled with -mdata-region=either enabled will still work.
The same reasoning applies to the absence of definitions for the
.either.text, .either.data and .either.bss sections as well. */
. = ALIGN(2);
*(.rodata .rodata.* .gnu.linkonce.r.* .const .const:*)
*(.rodata1)
*(.eh_frame_hdr)
KEEP (*(.eh_frame))
. = ALIGN(2);
KEEP (*(.gcc_except_table)) *(.gcc_except_table.*)
PROVIDE (__preinit_array_start = .);
KEEP (*(.preinit_array))
@@ -61,6 +81,17 @@ SECTIONS
PROVIDE (__fini_array_end = .);
LONG(0); /* Sentinel. */
} > ROM
/* Note: This is a separate .rodata section for sections which are
read only but which older linkers treat as read-write.
This prevents older linkers from marking the entire .rodata
section as read-write. */
.rodata2 : {
. = ALIGN(2);
*(.eh_frame_hdr)
KEEP (*(.eh_frame))
/* gcc uses crtbegin.o to find the start of the constructors, so
we make sure it is first. Because this is a wildcard, it
doesn't matter if the user does not actually link against
@@ -83,11 +114,19 @@ SECTIONS
KEEP (*(.dtors))
} > ROM
.upper.data :
.upper.rodata :
{
/* Note: If this section is not defined then please add:
*(.either.rodata.*) *(.either.rodata)
to the definition of the .rodata section above. This
will allow code compiled with -mdata-region=either to
work properly. */
. = ALIGN(2);
*(.upper.data.* .upper.data)
} > HIFRAM
*(.upper.rodata.* .upper.rodata)
} > HIROM
.data :
{
@@ -100,7 +139,14 @@ SECTIONS
*(.data.rel.ro.local) *(.data.rel.ro*)
*(.dynamic)
. = ALIGN(2);
*(.data .data.* .gnu.linkonce.d.*)
/* See the note in .rodata section about why we do not have this line here:
*(.either.data.* .either.data)
*/
KEEP (*(.gnu.linkonce.d.*personality*))
SORT(CONSTRUCTORS)
*(.data1)
@@ -113,24 +159,109 @@ SECTIONS
*(.sdata .sdata.* .gnu.linkonce.s.* D_2 D_1)
. = ALIGN(2);
_edata = .;
PROVIDE (edata = .);
PROVIDE (__dataend = .);
} > RAM
/* Note that crt0 assumes this is a multiple of two; all the
start/stop symbols are also assumed word-aligned. */
PROVIDE(__romdatastart = LOADADDR(.data));
PROVIDE (__romdatacopysize = SIZEOF(.data));
/* See the comment in the .upper.data section about the need
to copy data from ROM into RAM at program start up. */
} > RAM AT> ROM
.upper.bss :
/* Note that crt0 assumes that __romdatacopysize is a multiple of two.
All the start/stop symbols are also assumed to be word-aligned. */
__romdatastart = LOADADDR(.data);
__romdatacopysize = SIZEOF(.data);
/* ------------------- start of .upper.data sections.---------------- */
/* Note: If both HIROM and HIFRAM are available then the .upper.data
section should look like this:
. = ALIGN(2);
.upper.data :
{
__upper_data_init = LOADADDR (.upper.data);
/* Status word. * /
SHORT(1);
__high_datastart = .;
*(.upper.data.* .upper.data)
__high_dataend = .;
} > HIFRAM AT> HIROM
__rom_highdatacopysize = SIZEOF(.upper.data) - 2;
__rom_highdatastart = LOADADDR(.upper.data) + 2;
If only HIFRAM is available then the layout below must look like this:
.upper.data :
{
. = ALIGN(2);
__high_datastart = .;
*(.upper.data.* .upper.data)
__high_dataend = .;
} > HIFRAM
__rom_highdatacopysize = SIZEOF(.upper.data);
.shadow.upper.data :
{
. = ALIGN(2);
__upper_data_init = .;
/* Status word. * /
SHORT(0);
/* Space for the copy of .upper.data. * /
. = . + SIZEOF(.upper.data) - 2;
} > HIFRAM
__rom_highdatastart = LOADADDR(.shadow.upper.data) + 2;
Note - remove the space in this sequence: * / (twice) when you copy one
of the script fragments above into your script.
Note - the symbols defined here are *not* enclosed by the PROVIDE
keyword. This is deliberate. The crt0 library provides weak
definitions of these symbols and those weak definitions *must* be
overriden by the correct values.
The status word is used to control how the .upper.data section
is initialized at application start up. If the word is non-zero
then data is copied from __rom_highdatastart to __high_datastart.
This corresponds with copying the contents of .upper.data from its
load address (HIROM) to its run-time address (HIFRAM) in the first
scenario, or from the .shadow.upper.section to the .upper.data in
the second scenario.
If the status word is zero then the data is copied the other way
and the word is set to one. This only happens when the second
scenario is in play, and only the very first time the application
starts running. This makes sure that the .shadow.upper.data section
contains a pristine copy of the .upper.data section that can be used
to reinitialize the .upper.data section upon device reset.
The status word is necessary as this allows us to have one routine
in crt0 that can handle either form of .upper.data layout. IE crt0
is linker script agnostic.
Note - if the .upper.data section is not going to be defined at all
then please add this line back into the .data section above:
*(.either.data.* .either.data)
*/
. = ALIGN(2);
.upper.data :
{
. = ALIGN(2);
PROVIDE (__high_bssstart = .);
*(.upper.bss.* .upper.bss)
PROVIDE (__high_bssend = .);
} > HIFRAM
__upper_data_init = LOADADDR (.upper.data);
/* Status word. */
SHORT(1);
__high_datastart = .;
*(.upper.data.* .upper.data)
__high_dataend = .;
} > HIFRAM AT> HIROM
__rom_highdatacopysize = SIZEOF(.upper.data) - 2;
__rom_highdatastart = LOADADDR(.upper.data) + 2;
/* ------------------- end of .upper.data sections.---------------- */
.bss :
{
@@ -140,53 +271,87 @@ SECTIONS
*(.dynbss)
*(.sbss .sbss.*)
*(.bss .bss.* .gnu.linkonce.b.*)
/* See the note in .rodata section about why we do not have this line here:
*(.either.bss.* .either.bss)
*/
. = ALIGN(2);
*(COMMON)
. = ALIGN(2);
PROVIDE (__bssend = .);
} > RAM
PROVIDE (__bsssize = SIZEOF(.bss));
/* This section contains data that is not initialised at startup. */
/* This section contains data that is not initialised at startup
*or* application reset. */
.noinit (NOLOAD) :
{
. = ALIGN(2);
PROVIDE (__noinit_start = .);
*(.noinit)
. = ALIGN(2);
*(COMMON)
PROVIDE (__noinit_end = .);
} > RAM
_end = .;
PROVIDE (end = .);
.upper.bss :
{
/* Note - if this section is not going to be defined then please
add this line back into the definition of the .bss section above:
*(.either.bss.* .either.bss)
*/
. = ALIGN(2);
__high_bssstart = .;
*(.upper.bss.* .upper.bss)
. = ALIGN(2);
__high_bssend = .;
} > HIFRAM
.stack (ORIGIN (HIFRAM) + LENGTH(HIFRAM)) :
/* We create this section so that "end" will always be in the
HIFRAM region (matching .stack below), even if the .upper.bss
section is empty. */
.heap_start :
{
. = ALIGN(2);
_end = .;
PROVIDE (end = .);
LONG(0);
} > HIFRAM
/* Note: We place the stack in HIFRAM because then there is less
chance that it will collide with allocated data in the RAM region.
In scripts targeted at real MCUs however it may be better to place
the stack and heap in RAM, as flash does have a limited number of
writes before failure.
Note - if the location of .stack is changed, then be sure to change
the definition of .heap_start above as well. */
.stack (ORIGIN (HIFRAM) + LENGTH (HIFRAM)) :
{
PROVIDE (__stack = .);
*(.stack)
}
/* This is just for crt0.S and interrupt handlers. */
.lowtext :
{
PROVIDE (_start = .);
. = ALIGN(2);
KEEP (*(SORT(.crt_*)))
KEEP (*(.lowtext))
} > ROM
.upper.text :
{
. = ALIGN(2);
*(.upper.text.* .upper.text)
} > HIFRAM
.text :
{
PROVIDE (_start = .);
. = ALIGN(2);
KEEP (*(SORT(.crt_*)))
. = ALIGN(2);
KEEP (*(.lowtext))
. = ALIGN(2);
*(.lower.text.* .lower.text)
. = ALIGN(2);
*(.text .stub .text.* .gnu.linkonce.t.* .text:*)
/* See the note in .rodata section about why we do not have this line here:
*(.either.text.* .either.text)
*/
KEEP (*(.text.*personality*))
/* .gnu.warning sections are handled specially by elf32.em. */
*(.gnu.warning)
@@ -200,6 +365,18 @@ SECTIONS
KEEP (*(.tm_clone_table))
} > ROM
.upper.text :
{
/* Note - if this section is not going to be included in the script
then please add this line back into the definition of the .text
section above:
*(.either.text.* .either.text)
*/
. = ALIGN(2);
*(.upper.text.* .upper.text)
} > HIROM
/* The rest are all not normally part of the runtime image. */
.MP430.attributes 0 :