Find a file
Patryk Duda cab341d29c arch/common: Fix moving location counter backwards when using LLD
In GNU LD, the location counter (the 'dot' variable) always refers to
the byte offset from the start of current object as mentioned in
documentation[1]:

```
'.' actually refers to the byte offset from the start of the current
containing object. Normally this is the SECTIONS statement, whose start
address is 0, hence '.' can be used as an absolute address. If '.' is
used inside a section description however, it refers to the byte offset
from the start of that section, not an absolute address.
```

For example, if the section 'rom_start':

rom_start : {
	. = 0x400;
	_vector_start = ABSOLUTE(.);
} > FLASH

has a starting address of 0x8000000, then _vector_start will be
0x8000400

However, behavior of LLVM LLD is quite different, the value of the
location counter is always absolute (see discussion [2]), so in the
example above, the linker will return error, because it will interpret
'. = 0x400' as an attempt to move the location counter backwards.

It could be fixed by changing line to '. += 0x400' (#54796) which will
move the location counter by 0x400 for both linkers, but it would work
only when we are at the beginning of section. Consider the following
example:

rom_start : {
	. = 0x400;
	KEEP(*(.boot_hdr.conf))
	. = 0x1000;
	KEEP(*(.boot_hdr.ivt))
	KEEP(*(.boot_hdr.data))
	KEEP(*(.boot_hdr.dcd_data))
	. = 0x2000;
	_vector_start = .;
} > FLASH

In this case, _vector_start will be 0x2000, but if we change
'. = 0x2000' to '. += 0x2000', then the value of _vector_start depends
on size of data in input sections (but it's 0x3000 at least).

Actually, this example comes from final linker script when compiling
firmware for mimxrt1170_evk_cm7 board. This board failed to boot
(#55296) after #54796 was merged.

This patch introduces method compatible with both linkers. We calculate
relative offset from the beginning of the section and use that value to
calculate number of bytes by which we should move the location counter
to get CONFIG_ROM_START_OFFSET.

[1] https://sourceware.org/binutils/docs/ld/Location-Counter.html
[2] https://discourse.llvm.org/t/lld-location-counter-inside-objects

Signed-off-by: Patryk Duda <pdk@semihalf.com>
2023-07-14 12:08:02 +02:00
.github doc: move requirements to doc/ 2023-07-12 09:13:49 -04:00
arch arch/common: Fix moving location counter backwards when using LLD 2023-07-14 12:08:02 +02:00
boards input: convert gt911 from kscan 2023-07-13 14:24:50 +00:00
cmake cmake: Fix code relocation functions with absolute paths 2023-07-10 12:05:00 +02:00
doc doc: align pseudo-Makefile with latest CMake changes 2023-07-13 14:27:56 +02:00
drivers drivers: mm: Fix macro call in RAT driver 2023-07-14 09:37:53 +02:00
dts input: convert gt911 from kscan 2023-07-13 14:24:50 +00:00
include/zephyr drivers: fix double promotion warning in sensor_value_from_float 2023-07-14 09:31:47 +00:00
kernel kernel: support dynamic thread stack allocation 2023-07-13 17:16:32 -04:00
lib lib: posix: pthread_rwlock: Fix a racy issue 2023-07-12 09:25:26 +02:00
misc misc: generated: update configs.c template with <zephyr/...> prefix 2022-05-09 12:45:29 -04:00
modules modules: hal_nordic: nrfx: Make ISO IN ZLP configurable 2023-07-14 09:37:04 +02:00
samples input: convert gt911 from kscan 2023-07-13 14:24:50 +00:00
scripts scripts: tests: Twister test expansion - quarantine 2023-07-13 14:18:27 +02:00
share cmake: boards: Fix issue with relative paths 2023-06-15 05:10:42 -04:00
snippets snippets: support for EXTRA_DTC_OVERLAY_FILE and EXTRA_CONF_FILE 2023-05-25 13:31:53 +00:00
soc soc/xtensa/nxp_adsp/CMakeLists.txt: use new WEST_SIGN_OPTS variable 2023-07-13 14:19:26 +02:00
submanifests west.yml: allow users to easily add more modules 2021-10-07 13:45:42 +02:00
subsys Bluetooth: Host: Introduce BT_CONN_PARAM_ANY 2023-07-14 09:40:52 +00:00
tests tests: code_relocation: support mr_canhubk3 boards 2023-07-14 09:38:43 +02:00
.checkpatch.conf checkpatch: Remove ext/ from excludes 2022-11-30 12:06:55 -05:00
.clang-format clang-format: flag *_SECTION_FOREACH as for loop 2023-05-26 11:04:54 -05:00
.codecov.yml yamllint: fix all yamllint comments errors 2023-01-04 01:16:45 +09:00
.editorconfig editorconfig: Improve verbosity 2022-04-28 08:55:39 -04:00
.gitattributes gitattributes: consider SVG files generated 2021-10-14 12:42:44 -04:00
.gitignore scripts: ci: check_compliance: add a no-modules Kconfig check 2023-07-05 09:11:02 +02:00
.gitlint gitlint: Stop ignoring merge, revert, fixup and squash commits 2022-01-10 08:13:36 -05:00
.mailmap mailmap: sort alphabetically 2023-05-15 13:23:32 -04:00
.yamllint scripts: compliance: add support for YAMLLint 2023-01-04 17:29:23 +01:00
CMakeLists.txt cmake/compiler: Add linker_script compiler property 2023-07-06 11:43:09 +02:00
CODE_OF_CONDUCT.md
CODEOWNERS soc: ti: cc13/26xx: clean up include hierarchy 2023-07-07 18:46:24 -04:00
CONTRIBUTING.rst doc: Fixed a link in CONTRIBUTING.rst 2019-02-28 12:46:04 -08:00
Kconfig kconfig: Clean up header comments and make them consistent 2019-11-04 17:31:27 -05:00
Kconfig.zephyr Kconfig: Tidy up dependants of NATIVE_APPLICATION 2023-07-05 07:01:19 -04:00
LICENSE
MAINTAINERS.yml MAINTAINERS: Renesas R-Car ARM64: add entry 2023-07-11 11:17:41 +02:00
README.rst readme: Add support for light/dark modes in the logo 2022-11-18 08:58:59 +01:00
VERSION release: bump main to v3.4.99 2023-06-16 13:29:34 -04:00
version.h.in cmake: generalize VERSION infrastructure for better reuse 2023-05-17 13:56:58 +02:00
west.yml manifest: hal_nordic: Update hal_nordic revision 2023-07-13 13:21:41 +02:00
zephyr-env.cmd
zephyr-env.sh everywhere: fix typos 2022-03-18 13:24:08 -04:00

.. raw:: html

   <a href="https://www.zephyrproject.org">
     <p align="center">
       <picture>
         <source media="(prefers-color-scheme: dark)" srcset="doc/_static/images/logo-readme-dark.svg">
         <source media="(prefers-color-scheme: light)" srcset="doc/_static/images/logo-readme-light.svg">
         <img src="doc/_static/images/logo-readme-light.svg">
       </picture>
     </p>
   </a>

   <a href="https://bestpractices.coreinfrastructure.org/projects/74"><img
   src="https://bestpractices.coreinfrastructure.org/projects/74/badge"></a>
   <a
   href="https://github.com/zephyrproject-rtos/zephyr/actions/workflows/twister.yaml?query=branch%3Amain">
   <img
   src="https://github.com/zephyrproject-rtos/zephyr/actions/workflows/twister.yaml/badge.svg?event=push"></a>


The Zephyr Project is a scalable real-time operating system (RTOS) supporting
multiple hardware architectures, optimized for resource constrained devices,
and built with security in mind.

The Zephyr OS is based on a small-footprint kernel designed for use on
resource-constrained systems: from simple embedded environmental sensors and
LED wearables to sophisticated smart watches and IoT wireless gateways.

The Zephyr kernel supports multiple architectures, including ARM (Cortex-A,
Cortex-R, Cortex-M), Intel x86, ARC, Nios II, Tensilica Xtensa, and RISC-V,
SPARC, MIPS, and a large number of `supported boards`_.

.. below included in doc/introduction/introduction.rst


Getting Started
***************

Welcome to Zephyr! See the `Introduction to Zephyr`_ for a high-level overview,
and the documentation's `Getting Started Guide`_ to start developing.

.. start_include_here

Community Support
*****************

Community support is provided via mailing lists and Discord; see the Resources
below for details.

.. _project-resources:

Resources
*********

Here's a quick summary of resources to help you find your way around:

* **Help**: `Asking for Help Tips`_
* **Documentation**: http://docs.zephyrproject.org (`Getting Started Guide`_)
* **Source Code**: https://github.com/zephyrproject-rtos/zephyr is the main
  repository; https://elixir.bootlin.com/zephyr/latest/source contains a
  searchable index
* **Releases**: https://github.com/zephyrproject-rtos/zephyr/releases
* **Samples and example code**: see `Sample and Demo Code Examples`_
* **Mailing Lists**: users@lists.zephyrproject.org and
  devel@lists.zephyrproject.org are the main user and developer mailing lists,
  respectively. You can join the developer's list and search its archives at
  `Zephyr Development mailing list`_. The other `Zephyr mailing list
  subgroups`_ have their own archives and sign-up pages.
* **Nightly CI Build Status**: https://lists.zephyrproject.org/g/builds
  The builds@lists.zephyrproject.org mailing list archives the CI nightly build results.
* **Chat**: Real-time chat happens in Zephyr's Discord Server. Use
  this `Discord Invite`_ to register.
* **Contributing**: see the `Contribution Guide`_
* **Wiki**: `Zephyr GitHub wiki`_
* **Issues**: https://github.com/zephyrproject-rtos/zephyr/issues
* **Security Issues**: Email vulnerabilities@zephyrproject.org to report
  security issues; also see our `Security`_ documentation. Security issues are
  tracked separately at https://zephyrprojectsec.atlassian.net.
* **Zephyr Project Website**: https://zephyrproject.org

.. _Discord Invite: https://chat.zephyrproject.org
.. _supported boards: http://docs.zephyrproject.org/latest/boards/index.html
.. _Zephyr Documentation: http://docs.zephyrproject.org
.. _Introduction to Zephyr: http://docs.zephyrproject.org/latest/introduction/index.html
.. _Getting Started Guide: http://docs.zephyrproject.org/latest/develop/getting_started/index.html
.. _Contribution Guide: http://docs.zephyrproject.org/latest/contribute/index.html
.. _Zephyr GitHub wiki: https://github.com/zephyrproject-rtos/zephyr/wiki
.. _Zephyr Development mailing list: https://lists.zephyrproject.org/g/devel
.. _Zephyr mailing list subgroups: https://lists.zephyrproject.org/g/main/subgroups
.. _Sample and Demo Code Examples: http://docs.zephyrproject.org/latest/samples/index.html
.. _Security: http://docs.zephyrproject.org/latest/security/index.html
.. _Asking for Help Tips: https://docs.zephyrproject.org/latest/develop/getting_started/index.html#asking-for-help