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Diffstat (limited to 'board/nokia/rx51/lowlevel_init.S')
| -rw-r--r-- | board/nokia/rx51/lowlevel_init.S | 209 |
1 files changed, 209 insertions, 0 deletions
diff --git a/board/nokia/rx51/lowlevel_init.S b/board/nokia/rx51/lowlevel_init.S new file mode 100644 index 000000000..055b1038d --- /dev/null +++ b/board/nokia/rx51/lowlevel_init.S @@ -0,0 +1,209 @@ +/* + * (C) Copyright 2011-2012 + * Pali Rohár <pali.rohar@gmail.com> + * + * 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 <config.h> + +relocaddr: /* address of this relocaddr section after coping */ + .word . /* address of section (calculated at compile time) */ + +startaddr: /* address of u-boot after copying */ + .word CONFIG_SYS_TEXT_BASE + +kernaddr: /* address of kernel after copying */ + .word KERNEL_ADDRESS + +kernsize: /* maximal size of kernel image */ + .word KERNEL_MAXSIZE + +kernoffs: /* offset of kernel image in loaded u-boot */ + .word KERNEL_OFFSET + +imagesize: /* maximal size of image */ + .word IMAGE_MAXSIZE + +ih_magic: /* IH_MAGIC in big endian from include/image.h */ + .word 0x56190527 + +/* + * Routine: save_boot_params (called after reset from start.S) + * Description: Copy attached kernel to address KERNEL_ADDRESS + * Copy u-boot to address CONFIG_SYS_TEXT_BASE + * Return to copied u-boot address + */ + +.global save_boot_params +save_boot_params: + + +/* Copy valid attached kernel to address KERNEL_ADDRESS */ + +copy_kernel_start: + adr r0, relocaddr /* r0 - address of section relocaddr */ + ldr r1, relocaddr /* r1 - address of relocaddr after relocation */ + cmp r0, r1 + + /* r4 - calculated offset */ + subhi r4, r0, r1 + sublo r4, r1, r0 + + /* r0 - start of kernel before */ + ldr r0, startaddr + addhi r0, r0, r4 + sublo r0, r0, r4 + ldr r1, kernoffs + add r0, r0, r1 + + /* r3 - start of kernel after */ + ldr r3, kernaddr + + /* r2 - end of kernel after */ + ldr r1, kernsize + add r2, r3, r1 + + /* r1 - end of kernel before */ + add r1, r0, r1 + + /* remove header in target kernel */ + mov r5, #0 + str r5, [r3] + + /* check for valid kernel uImage */ + ldr r4, [r0] /* r4 - 4 bytes header of kernel */ + ldr r5, ih_magic /* r5 - IH_MAGIC */ + cmp r4, r5 + bne copy_kernel_end /* skip if invalid image */ + +copy_kernel_loop: + ldmdb r1!, {r3 - r10} + stmdb r2!, {r3 - r10} + cmp r1, r0 + bhi copy_kernel_loop + +copy_kernel_end: + mov r5, #0 + str r5, [r0] /* remove 4 bytes header of kernel */ + + +/* Fix u-boot code */ + +fix_start: + adr r0, relocaddr /* r0 - address of section relocaddr */ + ldr r1, relocaddr /* r1 - address of relocaddr after relocation */ + cmp r0, r1 + + beq copy_uboot_end /* skip if u-boot is on correct address */ + + /* r5 - calculated offset */ + subhi r5, r0, r1 + sublo r5, r1, r0 + + /* r6 - maximal u-boot size */ + ldr r6, imagesize + + /* fix return address */ + subhi lr, lr, r5 + addlo lr, lr, r5 + + /* r1 - start of u-boot after */ + ldr r1, startaddr + + /* r0 - start of u-boot before */ + addhi r0, r1, r5 + sublo r0, r1, r5 + + /* check if we need to move uboot copy code before calling it */ + cmp r5, r6 + bhi copy_uboot_start /* now coping u-boot code directly is safe */ + + +copy_code_start: + /* r0 - start of u-boot before */ + /* r1 - start of u-boot after */ + /* r6 - maximal u-boot size */ + + /* r7 - maximal kernel size */ + ldr r7, kernsize + + /* r4 - end of kernel before */ + add r4, r0, r6 + add r4, r4, r7 + + /* r5 - end of u-boot after */ + ldr r5, startaddr + add r5, r5, r6 + + /* r2 - start of loop code after */ + cmp r4, r5 /* higher address (r4 or r5) */ + movhs r2, r4 + movlo r2, r5 + + /* r3 - end of loop code before */ + adr r3, end + + /* r4 - end of loop code after */ + adr r4, copy_uboot_start + sub r4, r3, r4 + add r4, r2, r4 + +copy_code_loop: + ldmdb r3!, {r7 - r10} + stmdb r4!, {r7 - r10} + cmp r4, r2 + bhi copy_code_loop + +copy_code_end: + mov pc, r2 + + +/* Copy u-boot to address CONFIG_SYS_TEXT_BASE */ + +copy_uboot_start: + /* r0 - start of u-boot before */ + /* r1 - start of u-boot after */ + /* r6 - maximal u-boot size */ + + /* r2 - end of u-boot after */ + add r2, r1, r6 + + /* condition for copying from left to right */ + cmp r0, r1 + addlo r1, r0, r6 /* r1 - end of u-boot before */ + blo copy_uboot_loop_right + +copy_uboot_loop_left: + ldmia r0!, {r3 - r10} + stmia r1!, {r3 - r10} + cmp r1, r2 + blo copy_uboot_loop_left + b copy_uboot_end + +copy_uboot_loop_right: + ldmdb r1!, {r3 - r10} + stmdb r2!, {r3 - r10} + cmp r1, r0 + bhi copy_uboot_loop_right + +copy_uboot_end: + bx lr + +end: |