u-boot.git/arch/arm/cpu/u-boot.lds, branch master

arm: Update linker scripts to ensure appended device tree is aligned

2026-01-20T18:06:41+00:00

With commit 0535e46d55d7 ("scripts/dtc: Update to upstream version
v1.7.2-35-g52f07dcca47c") it is now a fatal error to U-Boot if our
device tree is not 8-byte aligned. In commit 85f586035d75 ("ARM: OMAP2+:
Pad SPL binary to 8-byte alignment before DTB") Beleswar Padhi explains
that we must have ALIGN(x) statements inside of a section to ensure that
padding is included and not simply that the linker address counter is
incremented. To that end, this patch:
- Expands some linker sections to be more readable when adding a second
  statement to the section.
- Aligns the final section before _end (for U-Boot) or
  _image_binary_end or __bss_end (for xPL phases) by 8-bytes by adding
  '. = ALIGN(8);' to the final section before the symbol.
- Ensure that we do have alignment by adding an ASSERT so that when not
  aligned we fail to link (and explain why).
- Remove now-spurious  '. = ALIGN(x);' statements that were intended to
  provide the above alignments.

Tested-by: Michal Simek  # Zynq
Reviewed-by: Ilias Apalodimas 
[trini: Also update arch/arm/cpu/armv8/u-boot.lds as Ilas requested]
Signed-off-by: Tom Rini

ARM: Align image end to 8 bytes to fit DT alignment

2025-06-02T23:25:35+00:00

Align U-Boot image end to 8 bytes to make sure DT alignment requirement
is fulfilled. This fixes a possible failure in fdt_find_separate() in
case the U-Boot image is aligned to 4 Bytes and DT is appended at the
end at already 8 Byte aligned offset.

Link: https://source.denx.de/u-boot/u-boot/-/issues/30
Reviewed-by: Simon Glass 
Reviewed-by: Tom Rini 
Signed-off-by: Marek Vasut

arm: Discard unwanted sections in linker script

2025-04-02T20:33:50+00:00

There are a handful of sections that are not useful in the U-Boot output
binary. At present, the linker script moves these to the end of the
binary, after the _image_binary_end marker symbol, so that they don't
get loaded.

The linker script syntax supports discarding sections that shouldn't be
included in the output. Switch to this instead, to make the intention
clearer and reduce the ELF sections that have to be handled later in the
build. This is also consistent with the other architectures' linker
scripts.

Signed-off-by: Sam Edwards 
Reviewed-by: Ilias Apalodimas

arm: Remove stray .mmutable reference in linker script

2025-04-02T20:33:50+00:00

The .mmutable section was deprecated in 2012 [1] and finally removed
entirely from U-Boot in 2022 [2], so this special handling is no longer
necessary. Remove it to tidy up the linker script.

[1]: dde3b70dcf3d ("arm: add a common .lds link script")
[2]: 3135ba642f9a ("arm: pxa: Remove CONFIG_CPU_PXA25X")

Signed-off-by: Sam Edwards 
Reviewed-by: Ilias Apalodimas

arm: move _end to linker symbols

2024-06-07T22:20:29+00:00

commit 6e2228fb052b ("Merge patch series "Clean up arm linker scripts")
was cleaning up linker scripts for armv7 and v8 but was leaving
_end and __secure_stack_start/end.

commit d0b5d9da5de2 ("arm: make _end compiler-generated")
was moving _end to be compiler generated. _end is defined as c variable
in its own section to force the compiler emit relative a reference.
However, defining those in the linker script will do the same thing
since [0].

So let's remove the special sections from the linker scripts, the
variable definitions from sections.c and define them as a symbols.
It's worth noting that _image_binary_end symbol is now redundant and
can be removed in the future.

- SPL

The .end section has been removed from the new binary
[ 5] .end
     PROGBITS         00000000fffdf488  000000000002f488  0
     0000000000000000 0000000000000000  0                 1
     [0000000000000003]: WRITE, ALLOC

$~ bloat-o-meter kria_old/spl/u-boot-spl krina_new/spl/u-boot-spl
add/remove: 0/0 grow/shrink: 0/0 up/down: 0/0 (0)
Function                                     old     new   delta
Total: Before=115980, After=115980, chg +0.00%

$~ readelf -sW kria_old/u-boot kria_new/u-boot | grep -w _end
 12047: 000000000813a0f0     0 OBJECT  GLOBAL DEFAULT   11 _end
 12047: 000000000813a118     0 NOTYPE  GLOBAL DEFAULT   11 _end

$~ readelf -sW kria_old/spl/u-boot-spl kria_new/spl/u-boot-spl | grep -w _end
  1605: 00000000fffdf488     0 OBJECT  GLOBAL DEFAULT    5 _end
  1603: 00000000fffdf498     0 NOTYPE  GLOBAL DEFAULT    4 _end

$~ readelf -sW old/u-boot new/u-boot | grep -w _end
  8847: 0000000000103710     0 OBJECT  GLOBAL DEFAULT   11 _end
  8847: 0000000000103738     0 NOTYPE  GLOBAL DEFAULT   11 _end

$~ readelf -sW old_v7/u-boot new_v7/u-boot | grep -w _end
 10638: 000da824     0 OBJECT  GLOBAL DEFAULT   10 _end
 10637: 000da84c     0 NOTYPE  GLOBAL DEFAULT   10 _end

- For both QEMU instances
$~ bloat-o-meter old/u-boot new/u-boot
add/remove: 0/0 grow/shrink: 1/0 up/down: 20/0 (20)
Function                                     old     new   delta
version_string                                50      70     +20
Total: Before=656915, After=656935, chg +0.00%

[0] binutils commit 6b3b0ab89663 ("Make linker assigned symbol dynamic only for shared object")

Signed-off-by: Ilias Apalodimas

arm: remove redundant section alignments

2024-03-29T14:39:25+00:00

Previous patches cleaning up linker symbols, also merged any explicit
. = ALIGN(x); into section definitions -- e.g
.bss ALIGN(x) : instead of

. = ALIGN(x);
. bss : {...}

However, if the output address is not specified then one will be chosen
for the section. This address will be adjusted to fit the alignment
requirement of the output section following the strictest alignment of
any input section contained within the output section. So let's get rid
of the redundant ALIGN directives when they are not needed.

While at add comments for the alignment of __bss_start/end since our
C runtime setup assembly assumes that __bss_start - __bss_end will be
a multiple of 4/8 for armv7 and armv8 respectively.

It's worth noting that the alignment is preserved on .rel.dyn for
mach-zynq which was explicitly aligning that section on an 8b
boundary instead of 4b one.

Reviewed-by: Richard Henderson 
Signed-off-by: Ilias Apalodimas

arm: move image_copy_start/end to linker symbols

2024-03-29T14:39:25+00:00

image_copy_start/end are defined as c variables in order to force the compiler
emit relative references. However, defining those within a section definition
will do the same thing since [0].

So let's remove the special sections from the linker scripts, the
variable definitions from sections.c and define them as a symbols within
a section.

[0] binutils commit 6b3b0ab89663 ("Make linker assigned symbol dynamic only for shared object")

Suggested-by: Sam Edwards 
Reviewed-by: Richard Henderson 
Tested-by: Sam Edwards  # Binary output identical
Signed-off-by: Ilias Apalodimas

arm: fix __efi_runtime_start/end definitions

2024-03-29T14:39:25+00:00

__efi_runtime_start/end are defined as c variables for arm7 only in
order to force the compiler emit relative references. However, defining
those within a section definition will do the same thing since [0].
On top of that the v8 linker scripts define it as a symbol.

So let's remove the special sections from the linker scripts, the
variable definitions from sections.c and define them as a symbols within
the correct section.

[0] binutils commit 6b3b0ab89663 ("Make linker assigned symbol dynamic only for shared object")

Suggested-by: Sam Edwards 
Reviewed-by: Sam Edwards 
Reviewed-by: Richard Henderson 
Tested-by: Sam Edwards  # Binary output identical
Signed-off-by: Ilias Apalodimas

arm: clean up v7 and v8 linker scripts for __rel_dyn_start/end

2024-03-29T14:39:25+00:00

commit 47bd65ef057f ("arm: make __rel_dyn_{start, end} compiler-generated")
were moving the __rel_dyn_start/end on c generated variables that were
injected in their own sections. The reason was that we needed relative
relocations for position independent code and linker bugs back then
prevented us from doing so [0].

However, the linker documentation pages states that symbols that are
defined within a section definition will create a relocatable
type with the value being a fixed offset from the base of a section [1].

[0] binutils commit 6b3b0ab89663 ("Make linker assigned symbol dynamic only for shared object")
[1] https://sourceware.org/binutils/docs/ld/Expression-Section.html

Suggested-by: Sam Edwards 
Reviewed-by: Sam Edwards 
Reviewed-by: Richard Henderson 
Tested-by: Sam Edwards  # Binary output identical
Signed-off-by: Ilias Apalodimas

arm: fix __efi_runtime_rel_start/end definitions

2024-03-29T14:39:25+00:00

__efi_runtime_rel_start/end are defined as c variables for arm7 only in
order to force the compiler emit relative references. However, defining
those within a section definition will do the same thing since [0].
On top of that the v8 linker scripts define it as a symbol.

So let's remove the special sections from the linker scripts, the
variable definitions from sections.c and define them as a symbols within
the correct section.

[0] binutils commit 6b3b0ab89663 ("Make linker assigned symbol dynamic only for shared object")

Suggested-by: Sam Edwards 
Reviewed-by: Sam Edwards 
Tested-by: Sam Edwards  # Binary output identical
Reviewed-by: Richard Henderson 
Signed-off-by: Ilias Apalodimas