cpu/mpc8xx/start.S

1 /* SPDX-License-Identifier: GPL-2.0+ */
8 /*  U-Boot - Startup Code for PowerPC based Embedded Boards
11  *  The processor starts at 0x00000100 and the code is executed
23 #include <asm-offsets.h>
33 #include <asm/u-boot.h>
60  * r3 - 1st arg to board_init(): IMMP pointer
61  * r4 - 2nd arg to board_init(): boot flag
64 	.long	0x27051956		/* U-Boot Magic Number			*/
76 	/*----------------------------------------------------------------------*/
84 	/*----------------------------------------------------------------------*/
92 	/*----------------------------------------------------------------------*/
112 	/*----------------------------------------------------------------------*/
119 	 *----------------------------------------------------------------------*/
123 	addi	r3, r3, in_flash - _start + EXC_OFF_SYS_RESET
130 	/*----------------------------------------------------------------------*/
134 	 * (i.e. set processor to normal mode).
150 	stw	r0, -4(r3)
151 	stw	r0, -8(r3)
152 	addi	r1, r3, -8
155 	addi	r1, r3, -8
159 	ori	r4, r4, (0x2000 - 4)
168 	/* let the C-code set up the rest					*/
171 	/*----------------------------------------------------------------------*/
176 	bl	cpu_init_f	/* run low-level CPU init code     (from Flash)	*/
180 	/* NOTREACHED - board_init_f() does not return */
322 /*------------------------------------------------------------------------------*/
346 	sub	r5, r5, r4
352 	 * New GOT-PTR = (old GOT-PTR - CONFIG_SYS_MONITOR_BASE) + Destination Address
356 	sub	r15, r10, r4
375 	la	r8,-4(r4)
376 	la	r7,-4(r3)
385 3:	lwzu	r0,-4(r8)
386 	stwu	r0,-4(r7)
417 	addi	r0, r10, in_ram - _start + EXC_OFF_SYS_RESET
433 	sub	r11,r3,r11
434 	addi	r3,r3,-4
437 	beq-	2f
450 	addi	r3,r3,-4
457 	beq-	5f
499 	bgelr				/* return if r7>=r8 - just in case */
511 	li	r7, .L_MachineCheck - _start + EXC_OFF_SYS_RESET
512 	li	r8, Alignment - _start + EXC_OFF_SYS_RESET
519 	li	r7, .L_Alignment - _start + EXC_OFF_SYS_RESET
522 	li	r7, .L_ProgramCheck - _start + EXC_OFF_SYS_RESET
525 	li	r7, .L_FPUnavailable - _start + EXC_OFF_SYS_RESET
526 	li	r8, SystemCall - _start + EXC_OFF_SYS_RESET
533 	li	r7, .L_SingleStep - _start + EXC_OFF_SYS_RESET
534 	li	r8, _end_of_vectors - _start + EXC_OFF_SYS_RESET