Nokia RX-51: Use U-Boot generic position independent code

Switch from custom board specific fixup/copy code to U-Boot generic
position independent code provided by config option POSITION_INDEPENDENT.

This also slightly decrease size of u-boot.bin binary (by 52 bytes). Note
that option POSITION_INDEPENDENT increase size but not more than custom
board fixup/copy code which is being deleted (as it is not needed anymore).

Signed-off-by: Pali Rohár <pali@kernel.org>

diff --git a/arch/arm/mach-omap2/omap3/Kconfig b/arch/arm/mach-omap2/omap3/Kconfig
index 81c898b..18574ab 100644 (file)
--- a/arch/arm/mach-omap2/omap3/Kconfig
+++ b/arch/arm/mach-omap2/omap3/Kconfig
@@ -107,6 +107,7 @@ config TARGET_OMAP3_LOGIC
 
 config TARGET_NOKIA_RX51
        bool "Nokia RX51"
+       select POSITION_INDEPENDENT
 
 config TARGET_TAO3530
        bool "TAO3530"

diff --git a/board/nokia/rx51/lowlevel_init.S b/board/nokia/rx51/lowlevel_init.S
index 632595f..dd3c830 100644 (file)
--- a/board/nokia/rx51/lowlevel_init.S
+++ b/board/nokia/rx51/lowlevel_init.S
@@ -33,16 +33,24 @@ z_magic:            /* LINUX_ARM_ZIMAGE_MAGIC */
 /*
  * 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:
-       /* Get return address */
-       ldr     lr, =save_boot_params_ret
 
-/* Copy valid attached kernel to address KERNEL_ADDRESS */
+/*
+ * Copy valid attached kernel to absolute address KERNEL_ADDRESS
+ *
+ * Nokia X-Loader is loading secondary image to address 0x80400000.
+ * NOLO is loading boot image to random place, so it doesn't really
+ * matter what is set in CONFIG_SYS_TEXT_BASE. We have to detect
+ * KERNEL_OFFSET from the current execution address and copy it to
+ * absolute address KERNEL_ADDRESS.
+ *
+ * Note that U-Boot has to be compiled with CONFIG_POSITION_INDEPENDENT
+ * because it is loaded at random address and not to the fixed address
+ * (CONFIG_SYS_TEXT_BASE).
+ */
 
 copy_kernel_start:
        adr     r0, relocaddr   /* r0 - address of section relocaddr */
@@ -100,110 +108,5 @@ copy_kernel_end:
        str     r5, [r0]        /* remove 4 bytes header of kernel uImage */
        str     r5, [r0, #36]   /* remove 4 bytes header of kernel zImage */
 
-
-/* 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
-
-       /* 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
- *
- * Nokia X-Loader loading secondary image to address 0x80400000
- * NOLO loading boot image to random place, so it doesn't really
- * matter what is set in CONFIG_SYS_TEXT_BASE. We have to copy
- * u-boot to CONFIG_SYS_TEXT_BASE address.
- */
-
-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:
+       /* Returns */
+       b       save_boot_params_ret

diff --git a/configs/nokia_rx51_defconfig b/configs/nokia_rx51_defconfig
index 3b559ab..1306c1f 100644 (file)
--- a/configs/nokia_rx51_defconfig
+++ b/configs/nokia_rx51_defconfig
@@ -9,7 +9,6 @@ CONFIG_INITRD_TAG=y
 CONFIG_REVISION_TAG=y
 CONFIG_STATIC_MACH_TYPE=y
 CONFIG_MACH_TYPE=1955
-CONFIG_SYS_TEXT_BASE=0x80008000
 CONFIG_SYS_MALLOC_LEN=0xc0000
 CONFIG_NR_DRAM_BANKS=2
 CONFIG_TARGET_NOKIA_RX51=y