diff options
Diffstat (limited to 'arch/arm/lib/relocate.S')
-rw-r--r-- | arch/arm/lib/relocate.S | 90 |
1 files changed, 90 insertions, 0 deletions
diff --git a/arch/arm/lib/relocate.S b/arch/arm/lib/relocate.S new file mode 100644 index 0000000..cd2bab6 --- /dev/null +++ b/arch/arm/lib/relocate.S @@ -0,0 +1,90 @@ +/* + * relocate - common relocation function for ARM U-Boot + * + * Copyright (c) 2013 Albert ARIBAUD <albert.u.boot@aribaud.net> + * + * See file CREDITS for list of people who contributed to this + * project. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 59 Temple Place, Suite 330, Boston, + * MA 02111-1307 USA + */ + +#include <linux/linkage.h> + +/* + * void relocate_code(addr_moni) + * + * This function relocates the monitor code. + * + * NOTE: + * To prevent the code below from containing references with an R_ARM_ABS32 + * relocation record type, we never refer to linker-defined symbols directly. + * Instead, we declare literals which contain their relative location with + * respect to relocate_code, and at run time, add relocate_code back to them. + */ + +ENTRY(relocate_code) + ldr r1, =__image_copy_start /* r1 <- SRC &__image_copy_start */ + subs r9, r0, r1 /* r9 <- relocation offset */ + beq relocate_done /* skip relocation */ + ldr r2, =__image_copy_end /* r2 <- SRC &__image_copy_end */ + +copy_loop: + ldmia r1!, {r10-r11} /* copy from source address [r1] */ + stmia r0!, {r10-r11} /* copy to target address [r0] */ + cmp r1, r2 /* until source end address [r2] */ + blo copy_loop + + /* + * fix .rel.dyn relocations + */ + ldr r2, =__rel_dyn_start /* r2 <- SRC &__rel_dyn_start */ + ldr r3, =__rel_dyn_end /* r3 <- SRC &__rel_dyn_end */ +fixloop: + ldmia r2!, {r0-r1} /* (r0,r1) <- (SRC location,fixup) */ + and r1, r1, #0xff + cmp r1, #23 /* relative fixup? */ + bne fixnext + + /* relative fix: increase location by offset */ + add r0, r0, r9 + ldr r1, [r0] + add r1, r1, r9 + str r1, [r0] +fixnext: + cmp r2, r3 + blo fixloop + +relocate_done: + +#ifdef __XSCALE__ + /* + * On xscale, icache must be invalidated and write buffers drained, + * even with cache disabled - 4.2.7 of xscale core developer's manual + */ + mcr p15, 0, r0, c7, c7, 0 /* invalidate icache */ + mcr p15, 0, r0, c7, c10, 4 /* drain write buffer */ +#endif + + /* ARMv4- don't know bx lr but the assembler fails to see that */ + +#ifdef __ARM_ARCH_4__ + mov pc, lr +#else + bx lr +#endif + +ENDPROC(relocate_code) |