/*
* These are defined in the board-specific linker script.
+ * Subtracting _start from them lets the linker put their
+ * relative position in the executable instead of leaving
+ * them null.
*/
-.globl _bss_start
-_bss_start:
- .word __bss_start
+.globl _bss_start_ofs
+_bss_start_ofs:
+ .word __bss_start - _start
-.globl _bss_end
-_bss_end:
- .word _end
+.globl _bss_end_ofs
+_bss_end_ofs:
+ .word _end - _start
#ifdef CONFIG_USE_IRQ
/* IRQ stack memory (calculated at run-time) */
IRQ_STACK_START_IN:
.word 0x0badc0de
-.globl _datarel_start
-_datarel_start:
- .word __datarel_start
-
-.globl _datarelrolocal_start
-_datarelrolocal_start:
- .word __datarelrolocal_start
-
-.globl _datarellocal_start
-_datarellocal_start:
- .word __datarellocal_start
-
-.globl _datarelro_start
-_datarelro_start:
- .word __datarelro_start
-
-.globl _got_start
-_got_start:
- .word __got_start
-
-.globl _got_end
-_got_end:
- .word __got_end
-
/*
* the actual reset code
*/
/* Set stackpointer in internal RAM to call board_init_f */
call_board_init_f:
ldr sp, =(CONFIG_SYS_INIT_SP_ADDR)
+ bic sp, sp, #7 /* 8-byte alignment for ABI compliance */
ldr r0,=0x00000000
bl board_init_f
mov r4, r0 /* save addr_sp */
mov r5, r1 /* save addr of gd */
mov r6, r2 /* save addr of destination */
- mov r7, r2 /* save addr of destination */
/* Set up the stack */
stack_setup:
mov sp, r4
adr r0, _start
- ldr r2, _TEXT_BASE
- ldr r3, _bss_start
- sub r2, r3, r2 /* r2 <- size of armboot */
- add r2, r0, r2 /* r2 <- source end address */
cmp r0, r6
- beq clear_bss
+ beq clear_bss /* skip relocation */
+ mov r1, r6 /* r1 <- scratch for copy_loop */
+ ldr r2, _TEXT_BASE
+ ldr r3, _bss_start_ofs
+ add r2, r0, r3 /* r2 <- source end address */
copy_loop:
ldmia r0!, {r9-r10} /* copy from source address [r0] */
- stmia r6!, {r9-r10} /* copy to target address [r1] */
+ stmia r1!, {r9-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end address [r2] */
blo copy_loop
#ifndef CONFIG_PRELOADER
- /* fix got entries */
- ldr r1, _TEXT_BASE /* Text base */
- mov r0, r7 /* reloc addr */
- ldr r2, _got_start /* addr in Flash */
- ldr r3, _got_end /* addr in Flash */
- sub r3, r3, r1
- add r3, r3, r0
- sub r2, r2, r1
- add r2, r2, r0
-
+ /*
+ * fix .rel.dyn relocations
+ */
+ ldr r0, _TEXT_BASE /* r0 <- Text base */
+ sub r9, r6, r0 /* r9 <- relocation offset */
+ ldr r10, _dynsym_start_ofs /* r10 <- sym table ofs */
+ add r10, r10, r0 /* r10 <- sym table in FLASH */
+ ldr r2, _rel_dyn_start_ofs /* r2 <- rel dyn start ofs */
+ add r2, r2, r0 /* r2 <- rel dyn start in FLASH */
+ ldr r3, _rel_dyn_end_ofs /* r3 <- rel dyn end ofs */
+ add r3, r3, r0 /* r3 <- rel dyn end in FLASH */
fixloop:
- ldr r4, [r2]
- sub r4, r4, r1
- add r4, r4, r0
- str r4, [r2]
- add r2, r2, #4
+ ldr r0, [r2] /* r0 <- location to fix up, IN FLASH! */
+ add r0, r0, r9 /* r0 <- location to fix up in RAM */
+ ldr r1, [r2, #4]
+ and r7, r1, #0xff
+ cmp r7, #23 /* relative fixup? */
+ beq fixrel
+ cmp r7, #2 /* absolute fixup? */
+ beq fixabs
+ /* ignore unknown type of fixup */
+ b fixnext
+fixabs:
+ /* absolute fix: set location to (offset) symbol value */
+ mov r1, r1, LSR #4 /* r1 <- symbol index in .dynsym */
+ add r1, r10, r1 /* r1 <- address of symbol in table */
+ ldr r1, [r1, #4] /* r1 <- symbol value */
+ add r1, r9 /* r1 <- relocated sym addr */
+ b fixnext
+fixrel:
+ /* relative fix: increase location by offset */
+ ldr r1, [r0]
+ add r1, r1, r9
+fixnext:
+ str r1, [r0]
+ add r2, r2, #8 /* each rel.dyn entry is 8 bytes */
cmp r2, r3
blo fixloop
#endif
clear_bss:
#ifndef CONFIG_PRELOADER
- ldr r0, _bss_start
- ldr r1, _bss_end
+ ldr r0, _bss_start_ofs
+ ldr r1, _bss_end_ofs
ldr r3, _TEXT_BASE /* Text base */
- mov r4, r7 /* reloc addr */
- sub r0, r0, r3
+ mov r4, r6 /* reloc addr */
add r0, r0, r4
- sub r1, r1, r3
add r1, r1, r4
mov r2, #0x00000000 /* clear */
* We are done. Do not return, instead branch to second part of board
* initialization, now running from RAM.
*/
- ldr r0, _TEXT_BASE
- ldr r2, _board_init_r
- sub r2, r2, r0
- add r2, r2, r7 /* position from board_init_r in RAM */
+ ldr r0, _board_init_r_ofs
+ adr r1, _start
+ add lr, r0, r1
+ add lr, lr, r9
/* setup parameters for board_init_r */
mov r0, r5 /* gd_t */
- mov r1, r7 /* dest_addr */
+ mov r1, r6 /* dest_addr */
/* jump to it ... */
- mov lr, r2
mov pc, lr
-_board_init_r: .word board_init_r
+_board_init_r_ofs:
+ .word board_init_r - _start
+_rel_dyn_start_ofs:
+ .word __rel_dyn_start - _start
+_rel_dyn_end_ofs:
+ .word __rel_dyn_end - _start
+_dynsym_start_ofs:
+ .word __dynsym_start - _start
/****************************************************************************/
/* */
projects / karo-tx-uboot.git / blobdiff