mirror of
https://github.com/AsahiLinux/u-boot
synced 2024-12-25 04:23:46 +00:00
203 lines
4.2 KiB
ArmAsm
203 lines
4.2 KiB
ArmAsm
/*
|
|
* Copyright (C) 2004 Sascha Hauer, Synertronixx GmbH
|
|
*
|
|
* This program is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU General Public License
|
|
* as published by the Free Software Foundation; either version 2
|
|
* of the License, or (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU General Public License
|
|
* along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
|
|
* 02111-1307, USA.
|
|
*
|
|
*/
|
|
|
|
#include <config.h>
|
|
#include <version.h>
|
|
#include <asm/arch/imx-regs.h>
|
|
|
|
.globl lowlevel_init
|
|
lowlevel_init:
|
|
|
|
mov r10, lr
|
|
|
|
/* Change PERCLK1DIV to 14 ie 14+1 */
|
|
ldr r0, =PCDR
|
|
ldr r1, =CONFIG_SYS_PCDR_VAL
|
|
str r1, [r0]
|
|
|
|
/* set MCU PLL Control Register 0 */
|
|
|
|
ldr r0, =MPCTL0
|
|
ldr r1, =CONFIG_SYS_MPCTL0_VAL
|
|
str r1, [r0]
|
|
|
|
/* set mpll restart bit */
|
|
ldr r0, =CSCR
|
|
ldr r1, [r0]
|
|
orr r1,r1,#(1<<21)
|
|
str r1, [r0]
|
|
|
|
mov r2,#0x10
|
|
1:
|
|
mov r3,#0x2000
|
|
2:
|
|
subs r3,r3,#1
|
|
bne 2b
|
|
|
|
subs r2,r2,#1
|
|
bne 1b
|
|
|
|
/* set System PLL Control Register 0 */
|
|
|
|
ldr r0, =SPCTL0
|
|
ldr r1, =CONFIG_SYS_SPCTL0_VAL
|
|
str r1, [r0]
|
|
|
|
/* set spll restart bit */
|
|
ldr r0, =CSCR
|
|
ldr r1, [r0]
|
|
orr r1,r1,#(1<<22)
|
|
str r1, [r0]
|
|
|
|
mov r2,#0x10
|
|
1:
|
|
mov r3,#0x2000
|
|
2:
|
|
subs r3,r3,#1
|
|
bne 2b
|
|
|
|
subs r2,r2,#1
|
|
bne 1b
|
|
|
|
ldr r0, =CSCR
|
|
ldr r1, =CONFIG_SYS_CSCR_VAL
|
|
str r1, [r0]
|
|
|
|
/* I have now read the ARM920 DataSheet back-to-Back, and have stumbled upon
|
|
*this.....
|
|
*
|
|
* It would appear that from a Cold-Boot the ARM920T enters "FastBus" mode CP15
|
|
* register 1, this stops it using the output of the PLL and thus runs at the
|
|
* slow rate. Unless you place the Core into "Asynch" mode, the CPU will never
|
|
* use the value set in the CM_OSC registers...regardless of what you set it
|
|
* too! Thus, although i thought i was running at 140MHz, i'm actually running
|
|
* at 40!..
|
|
|
|
* Slapping this into my bootloader does the trick...
|
|
|
|
* MRC p15,0,r0,c1,c0,0 ; read core configuration register
|
|
* ORR r0,r0,#0xC0000000 ; set asynchronous clocks and not fastbus mode
|
|
* MCR p15,0,r0,c1,c0,0 ; write modified value to core configuration
|
|
* register
|
|
*/
|
|
MRC p15,0,r0,c1,c0,0
|
|
ORR r0,r0,#0xC0000000
|
|
MCR p15,0,r0,c1,c0,0
|
|
|
|
ldr r0, =GPR(0)
|
|
ldr r1, =CONFIG_SYS_GPR_A_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =GIUS(0)
|
|
ldr r1, =CONFIG_SYS_GIUS_A_VAL
|
|
str r1, [r0]
|
|
|
|
/* CS3 becomes CS3 by clearing reset default bit 1 in FMCR */
|
|
|
|
ldr r0, =FMCR
|
|
ldr r1, =CONFIG_SYS_FMCR_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS0U
|
|
ldr r1, =CONFIG_SYS_CS0U_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS0L
|
|
ldr r1, =CONFIG_SYS_CS0L_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS1U
|
|
ldr r1, =CONFIG_SYS_CS1U_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS1L
|
|
ldr r1, =CONFIG_SYS_CS1L_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS2U
|
|
ldr r1, =CONFIG_SYS_CS2U_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS2L
|
|
ldr r1, =CONFIG_SYS_CS2L_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS3U
|
|
ldr r1, =CONFIG_SYS_CS3U_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS3L
|
|
ldr r1, =CONFIG_SYS_CS3L_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS4U
|
|
ldr r1, =CONFIG_SYS_CS4U_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS4L
|
|
ldr r1, =CONFIG_SYS_CS4L_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS5U
|
|
ldr r1, =CONFIG_SYS_CS5U_VAL
|
|
str r1, [r0]
|
|
|
|
ldr r0, =CS5L
|
|
ldr r1, =CONFIG_SYS_CS5L_VAL
|
|
str r1, [r0]
|
|
|
|
/* SDRAM Setup */
|
|
|
|
ldr r0, =SDCTL0
|
|
ldr r1, =PRECHARGE_CMD
|
|
str r1, [r0]
|
|
|
|
ldr r0, =0x08200000
|
|
ldr r1, =0x0 /* Issue Precharge all Command */
|
|
str r1, [r0]
|
|
|
|
ldr r0, =SDCTL0
|
|
ldr r1, =AUTOREFRESH_CMD
|
|
str r1, [r0]
|
|
|
|
ldr r0, =0x08000000
|
|
ldr r1, =0x0 /* Issue AutoRefresh Command */
|
|
str r1, [r0]
|
|
str r1, [r0]
|
|
str r1, [r0]
|
|
str r1, [r0]
|
|
str r1, [r0]
|
|
str r1, [r0]
|
|
str r1, [r0]
|
|
str r1, [r0]
|
|
|
|
ldr r0, =SDCTL0
|
|
ldr r1, =0xb10a8300
|
|
str r1, [r0]
|
|
|
|
ldr r0, =0x08223000 /* CAS Latency 2 */
|
|
ldr r1, =0x0 /* Issue Mode Register Command, Burst Length = 8 */
|
|
str r1, [r0]
|
|
|
|
ldr r0, =SDCTL0
|
|
ldr r1, =0x810a8200 /* Set to Normal Mode CAS 2 */
|
|
str r1, [r0]
|
|
|
|
mov pc,r10
|