| Message ID | 20240313162324.2117909-8-ilias.apalodimas@linaro.org |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Clean up arm linker scripts | expand |
On 3/13/24 06:23, Ilias Apalodimas wrote: > 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. > > Signed-off-by: Ilias Apalodimas<ilias.apalodimas@linaro.org> > --- > arch/arm/cpu/armv8/u-boot.lds | 9 ++++++--- > arch/arm/cpu/u-boot.lds | 8 ++++++-- > arch/arm/mach-zynq/u-boot.lds | 4 ++-- > 3 files changed, 14 insertions(+), 7 deletions(-) Reviewed-by: Richard Henderson <richard.henderson@linaro.org> r~
diff --git a/arch/arm/cpu/armv8/u-boot.lds b/arch/arm/cpu/armv8/u-boot.lds index 147a6e8028d5..857f44412e07 100644 --- a/arch/arm/cpu/armv8/u-boot.lds +++ b/arch/arm/cpu/armv8/u-boot.lds @@ -115,7 +115,7 @@ SECTIONS KEEP(*(SORT(__u_boot_list*))); } - .efi_runtime_rel ALIGN(8) : { + .efi_runtime_rel : { __efi_runtime_rel_start = .; *(.rel*.efi_runtime) *(.rel*.efi_runtime.*) @@ -125,7 +125,7 @@ SECTIONS . = ALIGN(8); __image_copy_end = .; - .rela.dyn ALIGN(8) : { + .rela.dyn : { __rel_dyn_start = .; *(.rela*) __rel_dyn_end = .; @@ -133,7 +133,10 @@ SECTIONS _end = .; - .bss ALIGN(8): { + /* + * arch/arm/lib/crt0_64.S assumes __bss_start - __bss_end % 8 == 0 + */ + .bss ALIGN(8) : { __bss_start = .; *(.bss*) . = ALIGN(8); diff --git a/arch/arm/cpu/u-boot.lds b/arch/arm/cpu/u-boot.lds index 798858e3ed6e..707b19795f08 100644 --- a/arch/arm/cpu/u-boot.lds +++ b/arch/arm/cpu/u-boot.lds @@ -43,7 +43,7 @@ SECTIONS } /* This needs to come before *(.text*) */ - .efi_runtime ALIGN(4) : { + .efi_runtime : { __efi_runtime_start = .; *(.text.efi_runtime*) *(.rodata.efi_runtime*) @@ -146,7 +146,7 @@ SECTIONS KEEP(*(SORT(__u_boot_list*))); } - .efi_runtime_rel ALIGN(4) : { + .efi_runtime_rel : { __efi_runtime_rel_start = .; *(.rel*.efi_runtime) *(.rel*.efi_runtime.*) @@ -156,6 +156,10 @@ SECTIONS . = ALIGN(4); __image_copy_end = .; + /* + * if CONFIG_USE_ARCH_MEMSET is not selected __bss_end - __bss_start + * needs to be a multiple of 4 and we overlay .bss with .rel.dyn + */ .rel.dyn ALIGN(4) : { __rel_dyn_start = .; *(.rel*) diff --git a/arch/arm/mach-zynq/u-boot.lds b/arch/arm/mach-zynq/u-boot.lds index f6c99a8ce218..3e0c96c50556 100644 --- a/arch/arm/mach-zynq/u-boot.lds +++ b/arch/arm/mach-zynq/u-boot.lds @@ -22,7 +22,7 @@ SECTIONS } /* This needs to come before *(.text*) */ - .efi_runtime ALIGN(4) : { + .efi_runtime : { __efi_runtime_start = .; *(.text.efi_runtime*) *(.rodata.efi_runtime*) @@ -52,7 +52,7 @@ SECTIONS KEEP(*(SORT(__u_boot_list*))); } - .efi_runtime_rel ALIGN(4) : { + .efi_runtime_rel : { __efi_runtime_rel_start = .; *(.rel*.efi_runtime) *(.rel*.efi_runtime.*)
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. Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> --- arch/arm/cpu/armv8/u-boot.lds | 9 ++++++--- arch/arm/cpu/u-boot.lds | 8 ++++++-- arch/arm/mach-zynq/u-boot.lds | 4 ++-- 3 files changed, 14 insertions(+), 7 deletions(-)