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/*
* Board specific setup info
*
* (C) Copyright 2004
* Texas Instruments, <www.ti.com>
* Richard Woodruff <r-woodruff2@ti.com>
*
* See file CREDITS for list of people who contributed to this
* project.
*
* 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/omap2420.h>
#include <asm/arch/mem.h>
#include <asm/arch/clock.h>
_TEXT_BASE:
.word CONFIG_SYS_TEXT_BASE /* sdram load addr from config.mk */
/**************************************************************************
* cpy_clk_code: relocates clock code into SRAM where its safer to execute
* R1 = SRAM destination address.
*************************************************************************/
.global cpy_clk_code
cpy_clk_code:
/* Copy DPLL code into SRAM */
adr r0, go_to_speed /* get addr of clock setting code */
mov r2, #384 /* r2 size to copy (div by 32 bytes) */
mov r1, r1 /* r1 <- dest address (passed in) */
add r2, r2, r0 /* r2 <- source end address */
next2:
ldmia r0!, {r3-r10} /* copy from source address [r0] */
stmia r1!, {r3-r10} /* copy to target address [r1] */
cmp r0, r2 /* until source end address [r2] */
bne next2
mov pc, lr /* back to caller */
/* ****************************************************************************
* go_to_speed: -Moves to bypass, -Commits clock dividers, -puts dpll at speed
* -executed from SRAM.
* R0 = PRCM_CLKCFG_CTRL - addr of valid reg
* R1 = CM_CLKEN_PLL - addr dpll ctlr reg
* R2 = dpll value
* R3 = CM_IDLEST_CKGEN - addr dpll lock wait
******************************************************************************/
.global go_to_speed
go_to_speed:
sub sp, sp, #0x4 /* get some stack space */
str r4, [sp] /* save r4's value */
/* move into fast relock bypass */
ldr r8, pll_ctl_add
mov r4, #0x2
str r4, [r8]
ldr r4, pll_stat
block:
ldr r8, [r4] /* wait for bypass to take effect */
and r8, r8, #0x3
cmp r8, #0x1
bne block
/* set new dpll dividers _after_ in bypass */
ldr r4, pll_div_add
ldr r8, pll_div_val
str r8, [r4]
/* now prepare GPMC (flash) for new dpll speed */
/* flash needs to be stable when we jump back to it */
ldr r4, cfg3_0_addr
ldr r8, cfg3_0_val
str r8, [r4]
ldr r4, cfg4_0_addr
ldr r8, cfg4_0_val
str r8, [r4]
ldr r4, cfg1_0_addr
ldr r8, [r4]
orr r8, r8, #0x3 /* up gpmc divider */
str r8, [r4]
/* setup to 2x loop though code. The first loop pre-loads the
* icache, the 2nd commits the prcm config, and locks the dpll
*/
mov r4, #0x1000 /* spin spin spin */
mov r8, #0x4 /* first pass condition & set registers */
cmp r8, #0x4
2:
ldrne r8, [r3] /* DPLL lock check */
and r8, r8, #0x7
cmp r8, #0x2
beq 4f
3:
subeq r8, r8, #0x1
streq r8, [r0] /* commit dividers (2nd time) */
nop
lloop1:
sub r4, r4, #0x1 /* Loop currently necessary else bad jumps */
nop
cmp r4, #0x0
bne lloop1
mov r4, #0x40000
cmp r8, #0x1
nop
streq r2, [r1] /* lock dpll (2nd time) */
nop
lloop2:
sub r4, r4, #0x1 /* loop currently necessary else bad jumps */
nop
cmp r4, #0x0
bne lloop2
mov r4, #0x40000
cmp r8, #0x1
nop
ldreq r8, [r3] /* get lock condition for dpll */
cmp r8, #0x4 /* first time though? */
bne 2b
moveq r8, #0x2 /* set to dpll check condition. */
beq 3b /* if condition not true branch */
4:
ldr r4, [sp]
add sp, sp, #0x4 /* return stack space */
mov pc, lr /* back to caller, locked */
_go_to_speed: .word go_to_speed
/* these constants need to be close for PIC code */
cfg3_0_addr:
.word GPMC_CONFIG3_0
cfg3_0_val:
.word H4_24XX_GPMC_CONFIG3_0
cfg4_0_addr:
.word GPMC_CONFIG4_0
cfg4_0_val:
.word H4_24XX_GPMC_CONFIG4_0
cfg1_0_addr:
.word GPMC_CONFIG1_0
pll_ctl_add:
.word CM_CLKEN_PLL
pll_stat:
.word CM_IDLEST_CKGEN
pll_div_add:
.word CM_CLKSEL1_PLL
pll_div_val:
.word DPLL_VAL /* DPLL setting (300MHz default) */
.globl lowlevel_init
lowlevel_init:
ldr sp, SRAM_STACK
str ip, [sp] /* stash old link register */
mov ip, lr /* save link reg across call */
bl s_init /* go setup pll,mux,memory */
ldr ip, [sp] /* restore save ip */
mov lr, ip /* restore link reg */
/* map interrupt controller */
ldr r0, VAL_INTH_SETUP
mcr p15, 0, r0, c15, c2, 4
/* back to arch calling code */
mov pc, lr
/* the literal pools origin */
.ltorg
REG_CONTROL_STATUS:
.word CONTROL_STATUS
VAL_INTH_SETUP:
.word PERIFERAL_PORT_BASE
SRAM_STACK:
.word LOW_LEVEL_SRAM_STACK
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