On Sun, 13 Oct 2013 09:10:28 +0200, Albert ARIBAUD albert.u.boot@aribaud.net wrote:
Remove the last uses of symbol offsets in ARM U-Boot. Remove some needless uses of _TEXT_BASE. Remove all _TEXT_BASE definitions.
Signed-off-by: Albert ARIBAUD albert.u.boot@aribaud.net
_TEXT_BASE was only used by ARM to allow resolution of symbol offsets, themselves only needed due to absolute relocations.
In some places, _TEXT_BASE was locally defined only to provide a literal for CONFIG_SYS_TEXT_BASE when the latter could have been used directly.
Sometimes even, _TEXT_BASE was defined but unused.
Since all relocations in ARM are relative, offsets, _TEXT_BASE and CONFIG_SYS_SYM_OFFSETS can be completely removed, and their uses can be replaced with adequate use of compiler-generated symbols from sections.c file.
Of course, I've done some non-regression testing before submitting, but this should undergo heavier testing by people with various ARM hardware. Considering the changes, checks should concentrate on:
- monitor_flash_len; - gd fields mon_len, fdt_blob, and reloc_off; - targets the lowlevel_init.S of which was moified.
Also note two things I've noticed only after posting v1:
diff --git a/README b/README index 0bb1ad5..1f9e16f 100644 --- a/README +++ b/README @@ -3522,12 +3522,6 @@ Configuration Settings: its config.mk file). If you find problems enabling this option on your board please report the problem and send patches!
-- CONFIG_SYS_SYM_OFFSETS
- This is set by architectures that use offsets for link symbols
- instead of absolute values. So bss_start is obtained using an
- offset _bss_start_ofs from CONFIG_SYS_TEXT_BASE, rather than
- directly. You should not need to touch this setting.
The removal of CONFIG_SYS_SYM_OFFSETS from the codebase is not mentioned in the commit message. Will add in v2.
diff --git a/arch/arm/cpu/arm926ejs/at91/lowlevel_init.S b/arch/arm/cpu/arm926ejs/at91/lowlevel_init.S index 39de2f4..7d1a633 100644 --- a/arch/arm/cpu/arm926ejs/at91/lowlevel_init.S +++ b/arch/arm/cpu/arm926ejs/at91/lowlevel_init.S @@ -26,27 +26,18 @@ #define CONFIG_SYS_MATRIX_EBICSA_VAL CONFIG_SYS_MATRIX_EBI0CSA_VAL #endif
-_TEXT_BASE:
- .word CONFIG_SYS_TEXT_BASE
.globl lowlevel_init .type lowlevel_init,function lowlevel_init:
- mov r5, pc /* r5 = POS1 + 4 current */
POS1:
- adr r5, POS1 /* r5 = POS1 run time */ ldr r0, =POS1 /* r0 = POS1 compile */
This could in fact use the existing lowlevel_init label rather than introduce POS1 for this purpose. Will fix in v2.
Amicalement,