Unable to build trusted firmware - A with SDK tool chain 1.0

[soumya-TI]

Running the following command to build a TI platform:
make ARCH=aarch64 CROSS_COMPILE=/home/a0498701local/zephyr-sdk-1.0.0/gnu/aarch64-zephyr-elf/bin/aarch64-zephyr-elf- PLAT=k3low TARGET_BOARD=am62lx

(.vectors+0x430): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.sync_exception_handler'
(.vectors+0x438): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.sync_exception_handler'
(.vectors+0x440): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.sync_exception_handler'
(.vectors+0x448): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.imp_def_el3_handler'
/home/a0498701local/Work_2/zspace/downstream/zephyrproject/modules/tee/tf-a/trusted-firmware-a/build/k3low/release/bl31/runtime_exceptions.o: in function `sync_exception_aarch32':
(.vectors+0x630): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.sync_exception_handler'
(.vectors+0x638): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.sync_exception_handler'
(.vectors+0x640): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.sync_exception_handler'
(.vectors+0x648): relocation truncated to fit: R_AARCH64_CONDBR19 against `.text.asm.imp_def_el3_handler'

truncation issues are found.

However the 0.17 version is able to build.

[stephanosio]

This is unlikely a toolchain bug. Some of the conditional branches in sync_exception_handler and imp_def_el3_handler seem to exceed the +/-1MiB range -- you should take a look at the code placement and make adjustments as needed.

[stephanosio]

By the way, I tried building TF-A with the command line you supplied above and was not able to reproduce the issue you are seeing.

TF-A at 4aef38a5bf03edfa615c1f8af5a49e7065f9fb3f

[soumya-TI]

Yeah seems like a code placement issue. Thanks for the note.

[soumya-TI]

I did some more investigation, tried finding if its an issue with TFA.
The TF-A commit for upstream has very minimal support for am62lx platform.
The downstream is here : https://github.com/TexasInstruments/arm-trusted-firmware/tree/ti-tfa-2.14.y
This has extensive memory layout usage. Yet to upstream.

This builds fine with Standard ARM GNU Toolchain 14.3 (arm-gnu-toolchain-14.3.rel1)

I believe, Zephyr SDK 1.0.0 applies both picolibc.ld and the custom linker script simultaneously, causing conflicts.

Embedded in aarch64-zephyr-elf-gcc (view with -dumpspecs)
*link: section contains:
%{!shared:%{!r:%{!T*: %:if-exists-then-else(%:find-file(picolibc.ld) -Tpicolibc.ld)}}}

*cpp: section contains:
%{-printf=*: -D_PICOLIBC_PRINTF='%*'} %{-scanf=*: -D_PICOLIBC_SCANF='%*'}

picolibc.ld is auto-included when no -T* flag is detected, even if --script is used

However the 0.17 there is no inclusion of picolib.

[keith-packard]

Good diagnosis. The solution is to replace -Wl,--script with -T so that the gcc driver doesn't also add -T picolibc.ld. This is fully compatible with other toolchains (including clang). I'm not sure why -Wl,--script would ever be used in place of -T.