u-boot.git/arch/arm/cpu/armv8/u-boot-spl.lds, branch master

arm: spl: Ensure 8 byte alignment of appended DTB without separate BSS

2026-02-09T15:33:20+00:00

Historically, when we have an appended device tree and also our
resulting binary will contain the BSS section, we have ensured that
everything will be where it's expected to be by declaring that the BSS
is overlayed with a symbol matches the end of the port of the ELF binary
that is objcopy'd to the binary we concatenate with. This in turn means
that the logic to generate a "pad" file, which is the size found in the
__bss_size symbol, will be correct and then we can concatenate the
device tree and it will begin at __bss_size at run time.

With commit 5ffc1dcc26d3 ("arm: Remove rel.dyn from SPL linker scripts")
we removed this overlay as part of trying to ensure that we met both the
requirements of the device tree to be 8 byte aligned as well as that our
logic to generate the -pad file would match what ended up in the
resulting binary. While it was correct to remove an unused section it
did not solve ultimately solve the problem for all cases.

To really fix the problem, we need to do two things. First, our final
section prior to _image_binary_end must be 8 byte aligned (for the case
of having a separate BSS and so our appended DTB exists at this
location). This cannot be '.binman_sym_table' as it may be empty, and in
turn the ELF type would be NOBITS and so not copied with objcopy. The
__u_boot_list section will never be empty, so it is our final section,
and ends with a '. = ALIGN(8)' statement. Second, as this is the end of
our copied data it is safe to declare that the BSS starts here, so use
the OVERLAY keyword to place the BSS here.

Fixes: 5ffc1dcc26d3 ("arm: Remove rel.dyn from SPL linker scripts")
Reported-by: Brian Sune 
Reported-by: Phil Phil Sutter 
Tested-by: Brian Sune 
Tested-by: Phil Sutter 
Tested-by: Greg Malysa 
Signed-off-by: Tom Rini

armv8: u-boot-spl.lds: Place binman symbols at end of binary

2026-01-28T20:41:21+00:00

It can be useful in xPL to access symbols from binman, such as the
offset/position and size of a binman entry.

Place these binman symbols together at the end of the xPL binary for
ARMv8, similar to ARM and RISC-V.

Signed-off-by: Jonas Karlman 
Reviewed-by: Simon Glass

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: armv8: Improve SPL data save and restore implementation

2025-02-25T16:54:02+00:00

Introduce a new symbol in the beginning of .data section in
the common ARMv8 linker script and use that as a reference
for data save and restore.

Previously, the code would rely on calculating the start of
the .data section address via data size, however, we observed
that the data size does not really reflect the SPL mapped
addresses.

In our case, the binman_sym section size was not included in
the data size, which will result in a wrong address for the
.data start section, which prevents us from properly saving
and restoring SPL data.

This approach skips the calculation for the starting address
of the .data section, and instead just defines the beginning
address of the .data section and calling the symbol as needed,
in which we think as a simpler and much more robust method.

Signed-off-by: Alif Zakuan Yuslaimi 
Signed-off-by: Tien Fong Chee 
Reviewed-by: Tien Fong Chee

armv8: Support not having separate BSS

2024-10-03T17:52:16+00:00

Separate BSS is current mandatory on armv8 but this is not useful for
early boot phases. Add support for the combined BSS.

Use an #ifdef to avoid using CONFIG_SPL_BSS_START_ADDR which is not
valid in this case.

Signed-off-by: Simon Glass 
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: 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: clean up v7 and v8 linker scripts for bss_start/end

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

commit 3ebd1cbc49f0 ("arm: make __bss_start and __bss_end__ compiler-generated")
and
commit f84a7b8f54db ("ARM: Fix __bss_start and __bss_end in linker scripts")
were moving the bss_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].
So let's start cleaning this up starting with the bss_start and bss_end
variables. Convert them into symbols within the .bss section definition.

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

Tested-by: Caleb Connolly  # Qualcomm sdm845
Tested-by: Sam Edwards  # Binary output identical
Signed-off-by: Ilias Apalodimas 
Reviewed-by: Richard Henderson

armv8: u-boot-spl.lds: mark __image_copy_start as symbol

2022-06-28T02:09:52+00:00

In arch/arm/lib/sections.c there is below code:
char __image_copy_start[0] __section(".__image_copy_start");
But actually 'objdump -t spl/u-boot-spl' not able to find out
symbol '__image_copy_start' for binman update image-pos/size.

So update link file

Signed-off-by: Peng Fan 
Reviewed-by: Tom Rini 
Reviewed-by: Alper Nebi Yasak

linker_lists: Rename sections to remove . prefix

2022-06-23T16:58:18+00:00

Rename the sections used to implement linker lists so they begin with
'__u_boot_list' rather than '.u_boot_list'. The double underscore at the
start is still distinct from the single underscore used by the symbol
names.

Having a '.' in the section names conflicts with clang's ASAN
instrumentation which tries to add redzones between the linker list
elements, causing expected accesses to fail. However, clang doesn't try
to add redzones to user sections, which are names with all alphanumeric
and underscore characters.

Signed-off-by: Andrew Scull 
Reviewed-by: Simon Glass