| /* SPDX-License-Identifier: GPL-2.0+ */ |
| /* |
| * armboot - Startup Code for ARM926EJS CPU-core |
| * |
| * Copyright (c) 2003 Texas Instruments |
| * |
| * ----- Adapted for OMAP1610 OMAP730 from ARM925t code ------ |
| * |
| * Copyright (c) 2001 Marius Groger <mag@sysgo.de> |
| * Copyright (c) 2002 Alex Zupke <azu@sysgo.de> |
| * Copyright (c) 2002 Gary Jennejohn <garyj@denx.de> |
| * Copyright (c) 2003 Richard Woodruff <r-woodruff2@ti.com> |
| * Copyright (c) 2003 Kshitij <kshitij@ti.com> |
| * Copyright (c) 2010 Albert Aribaud <albert.u.boot@aribaud.net> |
| * |
| * Change to support call back into iMX28 bootrom |
| * Copyright (c) 2011 Marek Vasut <marek.vasut@gmail.com> |
| * on behalf of DENX Software Engineering GmbH |
| */ |
| |
| #include <asm-offsets.h> |
| #include <config.h> |
| #include <system-constants.h> |
| |
| /* |
| ************************************************************************* |
| * |
| * Startup Code (reset vector) |
| * |
| * do important init only if we don't start from memory! |
| * setup Memory and board specific bits prior to relocation. |
| * relocate armboot to ram |
| * setup stack |
| * |
| ************************************************************************* |
| */ |
| |
| .globl reset |
| reset: |
| /* |
| * If the CPU is configured in "Wait JTAG connection mode", the stack |
| * pointer is not configured and is zero. This will cause crash when |
| * trying to push data onto stack right below here. Load the SP and make |
| * it point to the end of OCRAM if the SP is zero. |
| */ |
| cmp sp, #0x00000000 |
| ldreq sp, =SYS_INIT_SP_ADDR |
| |
| /* |
| * Store all registers on old stack pointer, this will allow us later to |
| * return to the BootROM and let the BootROM load U-Boot into RAM. |
| * |
| * WARNING: Register r0 and r1 are used by the BootROM to pass data |
| * to the called code. Register r0 will contain arbitrary |
| * data that are set in the BootStream. In case this code |
| * was started with CALL instruction, register r1 will contain |
| * pointer to the return value this function can then set. |
| * The code below MUST NOT CHANGE register r0 and r1 ! |
| */ |
| push {r0-r12,r14} |
| |
| /* Save control register c1 */ |
| mrc p15, 0, r2, c1, c0, 0 |
| push {r2} |
| |
| /* Set the cpu to SVC32 mode and store old CPSR register content. */ |
| mrs r2, cpsr |
| push {r2} |
| bic r2, r2, #0x1f |
| orr r2, r2, #0xd3 |
| msr cpsr, r2 |
| |
| bl board_init_ll |
| |
| /* Restore BootROM's CPU mode (especially FIQ). */ |
| pop {r2} |
| msr cpsr,r2 |
| |
| /* |
| * Restore c1 register. Especially set exception vector location |
| * back to BootROM space which is required by bootrom for USB boot. |
| */ |
| pop {r2} |
| mcr p15, 0, r2, c1, c0, 0 |
| |
| pop {r0-r12,r14} |
| |
| /* |
| * In case this code was started by the CALL instruction, the register |
| * r0 is examined by the BootROM after this code returns. The value in |
| * r0 must be set to 0 to indicate successful return. |
| */ |
| mov r0, #0 |
| |
| bx lr |