u-boot/board/incaip/lowlevel_init.S
Shinya Kuribayashi 43c509254f Use jr as register jump instruction
Current assembler codes are inconsistent in the way of register jump
instruction usage; some use jr, some use j. Of course GNU as allows both
usages, but as can be expected from `Jump Register' the mnemonic `jr' is
more intuitive than `j'. For example, Linux doesn't have `j <reg>' usage
at all.

Signed-off-by: Shinya Kuribayashi <skuribay@ruby.dti.ne.jp>
2008-04-18 00:47:29 -07:00

305 lines
5.5 KiB
ArmAsm

/*
* Memory sub-system initialization code for INCA-IP development board.
*
* Copyright (c) 2003 Wolfgang Denk <wd@denx.de>
*
* 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/regdef.h>
#define EBU_MODUL_BASE 0xB8000200
#define EBU_CLC(value) 0x0000(value)
#define EBU_CON(value) 0x0010(value)
#define EBU_ADDSEL0(value) 0x0020(value)
#define EBU_ADDSEL1(value) 0x0024(value)
#define EBU_ADDSEL2(value) 0x0028(value)
#define EBU_BUSCON0(value) 0x0060(value)
#define EBU_BUSCON1(value) 0x0064(value)
#define EBU_BUSCON2(value) 0x0068(value)
#define MC_MODUL_BASE 0xBF800000
#define MC_ERRCAUSE(value) 0x0100(value)
#define MC_ERRADDR(value) 0x0108(value)
#define MC_IOGP(value) 0x0800(value)
#define MC_SELFRFSH(value) 0x0A00(value)
#define MC_CTRLENA(value) 0x1000(value)
#define MC_MRSCODE(value) 0x1008(value)
#define MC_CFGDW(value) 0x1010(value)
#define MC_CFGPB0(value) 0x1018(value)
#define MC_LATENCY(value) 0x1038(value)
#define MC_TREFRESH(value) 0x1040(value)
#define CGU_MODUL_BASE 0xBF107000
#define CGU_PLL1CR(value) 0x0008(value)
#define CGU_DIVCR(value) 0x0010(value)
#define CGU_MUXCR(value) 0x0014(value)
#define CGU_PLL1SR(value) 0x000C(value)
.set noreorder
/*
* void ebu_init(long)
*
* a0 has the clock value we are going to run at
*/
.globl ebu_init
.ent ebu_init
ebu_init:
__ebu_init:
li t1, EBU_MODUL_BASE
li t2, 0xA0000041
sw t2, EBU_ADDSEL0(t1)
li t2, 0xA0800041
sw t2, EBU_ADDSEL2(t1)
li t2, 0xBE0000F1
sw t2, EBU_ADDSEL1(t1)
li t3, 100000000
beq a0, t3, 1f
nop
li t3, 133000000
beq a0, t3, 2f
nop
li t3, 150000000
beq a0, t3, 2f
nop
b 3f
nop
/* 100 MHz */
1:
li t2, 0x8841417D
sw t2, EBU_BUSCON0(t1)
sw t2, EBU_BUSCON2(t1)
li t2, 0x684142BD
b 3f
sw t2, EBU_BUSCON1(t1) /* delay slot */
/* 133 or 150 MHz */
2:
li t2, 0x8841417E
sw t2, EBU_BUSCON0(t1)
sw t2, EBU_BUSCON2(t1)
li t2, 0x684143FD
sw t2, EBU_BUSCON1(t1)
3:
jr ra
nop
.end ebu_init
/*
* void cgu_init(long)
*
* a0 has the clock value
*/
.globl cgu_init
.ent cgu_init
cgu_init:
__cgu_init:
li t1, CGU_MODUL_BASE
li t3, 100000000
beq a0, t3, 1f
nop
li t3, 133000000
beq a0, t3, 2f
nop
li t3, 150000000
beq a0, t3, 3f
nop
b 5f
nop
/* 100 MHz clock */
1:
li t2, 0x80000014
sw t2, CGU_DIVCR(t1)
li t2, 0x80000000
sw t2, CGU_MUXCR(t1)
li t2, 0x800B0001
b 5f
sw t2, CGU_PLL1CR(t1) /* delay slot */
/* 133 MHz clock */
2:
li t2, 0x80000054
sw t2, CGU_DIVCR(t1)
li t2, 0x80000000
sw t2, CGU_MUXCR(t1)
li t2, 0x800B0001
b 5f
sw t2, CGU_PLL1CR(t1) /* delay slot */
/* 150 MHz clock */
3:
li t2, 0x80000017
sw t2, CGU_DIVCR(t1)
li t2, 0xC00B0001
sw t2, CGU_PLL1CR(t1)
li t3, 0x80000000
4:
lw t2, CGU_PLL1SR(t1)
and t2, t2, t3
beq t2, zero, 4b
nop
li t2, 0x80000001
sw t2, CGU_MUXCR(t1)
5:
jr ra
nop
.end cgu_init
/*
* void sdram_init(long)
*
* a0 has the clock value
*/
.globl sdram_init
.ent sdram_init
sdram_init:
__sdram_init:
li t1, MC_MODUL_BASE
#if 0
/* Disable memory controller before changing any of its registers */
sw zero, MC_CTRLENA(t1)
#endif
li t2, 100000000
beq a0, t2, 1f
nop
li t2, 133000000
beq a0, t2, 2f
nop
li t2, 150000000
beq a0, t2, 3f
nop
b 5f
nop
/* 100 MHz clock */
1:
/* Set clock ratio (clkrat=1:1, rddel=3) */
li t2, 0x00000003
sw t2, MC_IOGP(t1)
/* Set sdram refresh rate (4K/64ms @ 100MHz) */
li t2, 0x0000061A
b 4f
sw t2, MC_TREFRESH(t1)
/* 133 MHz clock */
2:
/* Set clock ratio (clkrat=1:1, rddel=3) */
li t2, 0x00000003
sw t2, MC_IOGP(t1)
/* Set sdram refresh rate (4K/64ms @ 133MHz) */
li t2, 0x00000822
b 4f
sw t2, MC_TREFRESH(t1)
/* 150 MHz clock */
3:
/* Set clock ratio (clkrat=3:2, rddel=4) */
li t2, 0x00000014
sw t2, MC_IOGP(t1)
/* Set sdram refresh rate (4K/64ms @ 150MHz) */
li t2, 0x00000927
sw t2, MC_TREFRESH(t1)
4:
/* Clear Error log registers */
sw zero, MC_ERRCAUSE(t1)
sw zero, MC_ERRADDR(t1)
/* Clear Power-down registers */
sw zero, MC_SELFRFSH(t1)
/* Set CAS Latency */
li t2, 0x00000020 /* CL = 2 */
sw t2, MC_MRSCODE(t1)
/* Set word width to 16 bit */
li t2, 0x2
sw t2, MC_CFGDW(t1)
/* Set CS0 to SDRAM parameters */
li t2, 0x000014C9
sw t2, MC_CFGPB0(t1)
/* Set SDRAM latency parameters */
li t2, 0x00026325 /* BC PC100 */
sw t2, MC_LATENCY(t1)
5:
/* Finally enable the controller */
li t2, 0x00000001
sw t2, MC_CTRLENA(t1)
jr ra
nop
.end sdram_init
.globl lowlevel_init
.ent lowlevel_init
lowlevel_init:
/* Disable Watchdog.
*/
la t9, disable_incaip_wdt
jalr t9
nop
/* EBU, CGU and SDRAM Initialization.
*/
li a0, CPU_CLOCK_RATE
move t0, ra
/* We rely on the fact that neither ebu_init() nor cgu_init() nor sdram_init()
* modify t0 and a0.
*/
bal __cgu_init
nop
bal __ebu_init
nop
bal __sdram_init
nop
move ra, t0
jr ra
nop
.end lowlevel_init