This implements the new option to clear BSS early in SPL for standard arm and arm64 crt0.
BSS is cleared before calling board_init_f() and thus not cleared before calling board_init_r() as it is not relocated in SPL.
Signed-off-by: Simon Goldschmidt simon.k.r.goldschmidt@gmail.com ---
Changes in v2: - add CONFIG_SPL_CLEAR_BSS_F implementation for arm64 also
arch/arm/lib/crt0.S | 22 ++++++++++++++++++++++ arch/arm/lib/crt0_64.S | 14 ++++++++++++++ 2 files changed, 36 insertions(+)
diff --git a/arch/arm/lib/crt0.S b/arch/arm/lib/crt0.S index fe312db690..b06e54e144 100644 --- a/arch/arm/lib/crt0.S +++ b/arch/arm/lib/crt0.S @@ -80,6 +80,26 @@ ENTRY(_main) mov r9, r0 bl board_init_f_init_reserve
+#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_CLEAR_BSS_F) + ldr r0, =__bss_start + +#ifdef CONFIG_USE_ARCH_MEMSET + ldr r3, =__bss_end + mov r1, #0x00000000 /* prepare zero to clear BSS */ + + subs r2, r3, r0 /* r2 = memset len */ + bl memset +#else + ldr r1, =__bss_end + mov r2, #0x00000000 /* prepare zero to clear BSS */ + +clbss_l:cmp r0, r1 /* while not at end of BSS */ + strlo r2, [r0] /* clear 32-bit BSS word */ + addlo r0, r0, #4 /* move to next */ + blo clbss_l +#endif +#endif + mov r0, #0 bl board_init_f
@@ -124,6 +144,7 @@ here: movne sp, r0 movne r9, r0 # endif +#if !defined(CONFIG_SPL_BUILD) || !defined(CONFIG_SPL_CLEAR_BSS_F) ldr r0, =__bss_start /* this is auto-relocated! */
#ifdef CONFIG_USE_ARCH_MEMSET @@ -141,6 +162,7 @@ clbss_l:cmp r0, r1 /* while not at end of BSS */ addlo r0, r0, #4 /* move to next */ blo clbss_l #endif +#endif
#if ! defined(CONFIG_SPL_BUILD) bl coloured_LED_init diff --git a/arch/arm/lib/crt0_64.S b/arch/arm/lib/crt0_64.S index d6b632aa87..82f643f737 100644 --- a/arch/arm/lib/crt0_64.S +++ b/arch/arm/lib/crt0_64.S @@ -86,6 +86,18 @@ ENTRY(_main) mov x18, x0 bl board_init_f_init_reserve
+#if defined(CONFIG_SPL_BUILD) && defined(CONFIG_SPL_CLEAR_BSS_F) +/* + * Clear BSS section + */ + ldr x0, =__bss_start + ldr x1, =__bss_end +clear_loop: + str xzr, [x0], #8 + cmp x0, x1 + b.lo clear_loop +#endif + mov x0, #0 bl board_init_f
@@ -136,6 +148,7 @@ relocation_return: mov sp, x0 #endif
+#if !defined(CONFIG_SPL_BUILD) || !defined(CONFIG_SPL_CLEAR_BSS_F) /* * Clear BSS section */ @@ -145,6 +158,7 @@ clear_loop: str xzr, [x0], #8 cmp x0, x1 b.lo clear_loop +#endif
/* call board_init_r(gd_t *id, ulong dest_addr) */ mov x0, x18 /* gd_t */