uboot/u-boot-stm32mp-2020.01/arch/arm/mach-at91/arm920t/lowlevel_init.S

152 lines
3.5 KiB
ArmAsm

/* SPDX-License-Identifier: GPL-2.0+ */
/*
* Copyright (C) 1999 2000 2001 Erik Mouw (J.A.K.Mouw@its.tudelft.nl) and
* Jan-Derk Bakker (J.D.Bakker@its.tudelft.nl)
*
* Modified for the at91rm9200dk board by
* (C) Copyright 2004
* Gary Jennejohn, DENX Software Engineering, <garyj@denx.de>
*/
#include <config.h>
#ifndef CONFIG_SKIP_LOWLEVEL_INIT
#include <asm/arch/hardware.h>
#include <asm/arch/at91_mc.h>
#include <asm/arch/at91_pmc.h>
#include <asm/arch/at91_pio.h>
#define ARM920T_CONTROL 0xC0000000 /* @ set bit 31 (iA) and 30 (nF) */
_MTEXT_BASE:
#undef START_FROM_MEM
#ifdef START_FROM_MEM
.word CONFIG_SYS_TEXT_BASE-PHYS_FLASH_1
#else
.word CONFIG_SYS_TEXT_BASE
#endif
.globl lowlevel_init
lowlevel_init:
ldr r1, =AT91_ASM_PMC_MOR
/* Main oscillator Enable register */
#ifdef CONFIG_SYS_USE_MAIN_OSCILLATOR
ldr r0, =0x0000FF01 /* Enable main oscillator */
#else
ldr r0, =0x0000FF00 /* Disable main oscillator */
#endif
str r0, [r1] /*AT91C_CKGR_MOR] */
/* Add loop to compensate Main Oscillator startup time */
ldr r0, =0x00000010
LoopOsc:
subs r0, r0, #1
bhi LoopOsc
/* memory control configuration */
/* this isn't very elegant, but what the heck */
ldr r0, =SMRDATA
ldr r1, _MTEXT_BASE
sub r0, r0, r1
ldr r2, =SMRDATAE
sub r2, r2, r1
pllloop:
/* the address */
ldr r1, [r0], #4
/* the value */
ldr r3, [r0], #4
str r3, [r1]
cmp r2, r0
bne pllloop
/* delay - this is all done by guess */
ldr r0, =0x00010000
/* (vs reading PMC_SR for LOCKA, LOCKB ... or MOSCS earlier) */
lock:
subs r0, r0, #1
bhi lock
ldr r0, =SMRDATA1
ldr r1, _MTEXT_BASE
sub r0, r0, r1
ldr r2, =SMRDATA1E
sub r2, r2, r1
sdinit:
/* the address */
ldr r1, [r0], #4
/* the value */
ldr r3, [r0], #4
str r3, [r1]
cmp r2, r0
bne sdinit
/* switch from FastBus to Asynchronous clock mode */
mrc p15, 0, r0, c1, c0, 0
orr r0, r0, #ARM920T_CONTROL
mcr p15, 0, r0, c1, c0, 0
/* everything is fine now */
mov pc, lr
.ltorg
SMRDATA:
.word AT91_ASM_MC_EBI_CFG
.word CONFIG_SYS_EBI_CFGR_VAL
.word AT91_ASM_MC_SMC_CSR0
.word CONFIG_SYS_SMC_CSR0_VAL
.word AT91_ASM_PMC_PLLAR
.word CONFIG_SYS_PLLAR_VAL
.word AT91_ASM_PMC_PLLBR
.word CONFIG_SYS_PLLBR_VAL
.word AT91_ASM_PMC_MCKR
.word CONFIG_SYS_MCKR_VAL
SMRDATAE:
/* here there's a delay */
SMRDATA1:
.word AT91_ASM_PIOC_ASR
.word CONFIG_SYS_PIOC_ASR_VAL
.word AT91_ASM_PIOC_BSR
.word CONFIG_SYS_PIOC_BSR_VAL
.word AT91_ASM_PIOC_PDR
.word CONFIG_SYS_PIOC_PDR_VAL
.word AT91_ASM_MC_EBI_CSA
.word CONFIG_SYS_EBI_CSA_VAL
.word AT91_ASM_MC_SDRAMC_CR
.word CONFIG_SYS_SDRC_CR_VAL
.word AT91_ASM_MC_SDRAMC_MR
.word CONFIG_SYS_SDRC_MR_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word AT91_ASM_MC_SDRAMC_MR
.word CONFIG_SYS_SDRC_MR_VAL1
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word AT91_ASM_MC_SDRAMC_MR
.word CONFIG_SYS_SDRC_MR_VAL2
.word CONFIG_SYS_SDRAM1
.word CONFIG_SYS_SDRAM_VAL
.word AT91_ASM_MC_SDRAMC_TR
.word CONFIG_SYS_SDRC_TR_VAL
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
.word AT91_ASM_MC_SDRAMC_MR
.word CONFIG_SYS_SDRC_MR_VAL3
.word CONFIG_SYS_SDRAM
.word CONFIG_SYS_SDRAM_VAL
SMRDATA1E:
/* SMRDATA1 is 176 bytes long */
#endif /* CONFIG_SKIP_LOWLEVEL_INIT */