avionic design with actual uboot and tooling

submodule of avionic design uboot bootloader and with included tools to
get you started , read readme.md and readme-tk1-loader.md

u-boot/board/nokia/rx51/lowlevel_init.S

@@ -0,0 +1,190 @@
+/*
+ * (C) Copyright 2011-2012
+ * Pali Rohár <pali.rohar@gmail.com>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#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:
+	/* Get return address */
+	ldr	lr, =save_boot_params_ret
+
+/* 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
+
+	/* 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: