diff options
Diffstat (limited to 'cpu/at32ap/start.S')
| -rw-r--r-- | cpu/at32ap/start.S | 113 |
1 files changed, 82 insertions, 31 deletions
diff --git a/cpu/at32ap/start.S b/cpu/at32ap/start.S index 79ee33b..ab8c2b7 100644 --- a/cpu/at32ap/start.S +++ b/cpu/at32ap/start.S @@ -70,32 +70,12 @@ _start: 2: lddpc sp, sp_init - /* - * Relocate the data section and initialize .bss. Everything - * is guaranteed to be at least doubleword aligned by the - * linker script. - */ - lddpc r12, .Ldata_vma - lddpc r11, .Ldata_lma - lddpc r10, .Ldata_end - sub r10, r12 -4: ld.d r8, r11++ - sub r10, 8 - st.d r12++, r8 - brne 4b - - mov r8, 0 - mov r9, 0 - lddpc r10, .Lbss_end - sub r10, r12 -4: sub r10, 8 - st.d r12++, r8 - brne 4b - /* Initialize the GOT pointer */ lddpc r6, got_init 3: rsub r6, pc - ld.w pc, r6[start_u_boot@got] + + /* Let's go */ + rjmp board_init_f .align 2 .type sp_init,@object @@ -103,11 +83,82 @@ sp_init: .long CFG_INIT_SP_ADDR got_init: .long 3b - _GLOBAL_OFFSET_TABLE_ -.Ldata_lma: - .long __data_lma -.Ldata_vma: - .long _data -.Ldata_end: - .long _edata -.Lbss_end: - .long _end + + /* + * void relocate_code(new_sp, new_gd, monitor_addr) + * + * Relocate the u-boot image into RAM and continue from there. + * Does not return. + */ + .global relocate_code + .type relocate_code,@function +relocate_code: + mov sp, r12 /* use new stack */ + mov r12, r11 /* save new_gd */ + mov r11, r10 /* save destination address */ + + /* copy .text section and flush the cache along the way */ + lda.w r8, _text + lda.w r9, _etext + sub lr, r10, r8 /* relocation offset */ + +1: ldm r8++, r0-r3 + stm r10, r0-r3 + sub r10, -16 + ldm r8++, r0-r3 + stm r10, r0-r3 + sub r10, -16 + cp.w r8, r9 + cache r10[-4], 0x0d /* dcache clean/invalidate */ + cache r10[-4], 0x01 /* icache invalidate */ + brlt 1b + + /* flush write buffer */ + sync 0 + + /* copy data sections */ + lda.w r9, _edata +1: ld.d r0, r8++ + st.d r10++, r0 + cp.w r8, r9 + brlt 1b + + /* zero out .bss */ + mov r0, 0 + mov r1, 0 + lda.w r9, _end + sub r9, r8 +1: st.d r10++, r0 + sub r9, 8 + brgt 1b + + /* jump to RAM */ + sub r0, pc, . - in_ram + add pc, r0, lr + + .align 2 +in_ram: + /* find the new GOT and relocate it */ + lddpc r6, got_init_reloc +3: rsub r6, pc + mov r8, r6 + lda.w r9, _egot + lda.w r10, _got + sub r9, r10 +1: ld.w r0, r8[0] + add r0, lr + st.w r8++, r0 + sub r9, 4 + brgt 1b + + /* Move the exception handlers */ + mfsr r2, SYSREG_EVBA + add r2, lr + mtsr SYSREG_EVBA, r2 + + /* Do the rest of the initialization sequence */ + call board_init_r + + .align 2 +got_init_reloc: + .long 3b - _GLOBAL_OFFSET_TABLE_ |