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| author | rev13@wp.pl <rev13@wp.pl> | 2015-03-01 11:44:39 (GMT) |
|---|---|---|
| committer | Tom Rini <trini@konsulko.com> | 2015-04-22 16:14:55 (GMT) |
| commit | 12d8a729137ec58107236c472ddb14a819e7bd0b (patch) | |
| tree | 9d4f065d21466e06071d29b1b86eb6d185f0dffb /arch/arm/lib/crt0.S | |
| parent | 5d27223ea5424fc157c8ac0afb236bc8cfcd1772 (diff) | |
| download | u-boot-12d8a729137ec58107236c472ddb14a819e7bd0b.tar.xz | |
ARM: Add ARMv7-M support
Signed-off-by: Kamil Lulko <rev13@wp.pl>
Diffstat (limited to 'arch/arm/lib/crt0.S')
| -rw-r--r-- | arch/arm/lib/crt0.S | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/arch/arm/lib/crt0.S b/arch/arm/lib/crt0.S index 92d3732..afd4f10 100644 --- a/arch/arm/lib/crt0.S +++ b/arch/arm/lib/crt0.S @@ -9,6 +9,9 @@ #include <config.h> #include <asm-offsets.h> #include <linux/linkage.h> +#ifdef CONFIG_CPU_V7M +#include <asm/armv7m.h> +#endif /* * This file handles the target-independent stages of the U-Boot @@ -66,15 +69,30 @@ ENTRY(_main) #else ldr sp, =(CONFIG_SYS_INIT_SP_ADDR) #endif +#if defined(CONFIG_CPU_V7M) /* v7M forbids using SP as BIC destination */ + mov r3, sp + bic r3, r3, #7 + mov sp, r3 +#else bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ +#endif mov r2, sp sub sp, sp, #GD_SIZE /* allocate one GD above SP */ +#if defined(CONFIG_CPU_V7M) /* v7M forbids using SP as BIC destination */ + mov r3, sp + bic r3, r3, #7 + mov sp, r3 +#else bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ +#endif mov r9, sp /* GD is above SP */ mov r1, sp mov r0, #0 clr_gd: cmp r1, r2 /* while not at end of GD */ +#if defined(CONFIG_CPU_V7M) + itt lo +#endif strlo r0, [r1] /* clear 32-bit GD word */ addlo r1, r1, #4 /* move to next */ blo clr_gd @@ -94,13 +112,22 @@ clr_gd: */ ldr sp, [r9, #GD_START_ADDR_SP] /* sp = gd->start_addr_sp */ +#if defined(CONFIG_CPU_V7M) /* v7M forbids using SP as BIC destination */ + mov r3, sp + bic r3, r3, #7 + mov sp, r3 +#else bic sp, sp, #7 /* 8-byte alignment for ABI compliance */ +#endif ldr r9, [r9, #GD_BD] /* r9 = gd->bd */ sub r9, r9, #GD_SIZE /* new GD is below bd */ adr lr, here ldr r0, [r9, #GD_RELOC_OFF] /* r0 = gd->reloc_off */ add lr, lr, r0 +#if defined(CONFIG_CPU_V7M) + orr lr, #1 /* As required by Thumb-only */ +#endif ldr r0, [r9, #GD_RELOCADDR] /* r0 = gd->relocaddr */ b relocate_code here: @@ -134,6 +161,9 @@ here: mov r2, #0x00000000 /* prepare zero to clear BSS */ clbss_l:cmp r0, r1 /* while not at end of BSS */ +#if defined(CONFIG_CPU_V7M) + itt lo +#endif strlo r2, [r0] /* clear 32-bit BSS word */ addlo r0, r0, #4 /* move to next */ blo clbss_l |