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/*
* WORK Microwave work_92105 board low level init
*
* (C) Copyright 2014 DENX Software Engineering GmbH
* Written-by: Albert ARIBAUD <albert.aribaud@3adev.fr>
*
* Low level init is called from SPL to set up the clocks.
* On entry, the LPC3250 is in Direct Run mode with all clocks
* running at 13 MHz; on exit, ARM clock is 208 MHz, HCLK is
* 104 MHz and PCLK is 13 MHz.
*
* This code must run from SRAM so that the clock changes do
* not prevent it from executing.
*
* SPDX-License-Identifier: GPL-2.0+
*/
.globl lowlevel_init
lowlevel_init:
/* Set ARM, HCLK, PCLK dividers for normal mode */
ldr r0, =0x0000003D
ldr r1, =0x40004040
str r0, [r1]
/* Start HCLK PLL for 208 MHz */
ldr r0, =0x0001401E
ldr r1, =0x40004058
str r0, [r1]
/* wait for HCLK PLL to lock */
1:
ldr r0, [r1]
ands r0, r0, #1
beq 1b
/* switch to normal mode */
ldr r1, =0x40004044
ldr r0, [r1]
orr r0, #0x00000004
str r0, [r1]
/* Return to U-Boot via saved link register */
mov pc, lr
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