u-boot/arch/arm/cpu/arm926ejs/orion5x/lowlevel_init.S
Albert ARIBAUD 57b4bce996 Replace obsolete e-mail address
Signed-off-by: Albert ARIBAUD <albert.u.boot@aribaud.net>
2011-04-27 19:38:09 +02:00

293 lines
7.7 KiB
ArmAsm

/*
* Copyright (C) 2010 Albert ARIBAUD <albert.u.boot@aribaud.net>
*
* (C) Copyright 2009
* Marvell Semiconductor <www.marvell.com>
* Written-by: Prafulla Wadaskar <prafulla@marvell.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., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include <config.h>
#include "asm/arch/orion5x.h"
/*
* Configuration values for SDRAM access setup
*/
#define SDRAM_CONFIG 0x3148400
#define SDRAM_MODE 0x62
#define SDRAM_CONTROL 0x4041000
#define SDRAM_TIME_CTRL_LOW 0x11602220
#define SDRAM_TIME_CTRL_HI 0x40c
#define SDRAM_OPEN_PAGE_EN 0x0
/* DDR 1 2x 32M NANYA NT5DS16M16CS-6K ==> 64MB */
#define SDRAM_BANK0_SIZE 0x3ff0001
#define SDRAM_ADDR_CTRL 0x10
#define SDRAM_OP_NOP 0x05
#define SDRAM_OP_SETMODE 0x03
#define SDRAM_PAD_CTRL_WR_EN 0x80000000
#define SDRAM_PAD_CTRL_TUNE_EN 0x00010000
#define SDRAM_PAD_CTRL_DRVN_MASK 0x0000003f
#define SDRAM_PAD_CTRL_DRVP_MASK 0x00000fc0
/*
* For Guideline MEM-3 - Drive Strength value
*/
#define DDR1_PAD_STRENGTH_DEFAULT 0x00001000
#define SDRAM_PAD_CTRL_DRV_STR_MASK 0x00003000
/*
* For Guideline MEM-4 - DQS Reference Delay Tuning
*/
#define MSAR_ARMDDRCLCK_MASK 0x000000f0
#define MSAR_ARMDDRCLCK_H_MASK 0x00000100
#define MSAR_ARMDDRCLCK_333_167 0x00000000
#define MSAR_ARMDDRCLCK_500_167 0x00000030
#define MSAR_ARMDDRCLCK_667_167 0x00000060
#define MSAR_ARMDDRCLCK_400_200_1 0x000001E0
#define MSAR_ARMDDRCLCK_400_200 0x00000010
#define MSAR_ARMDDRCLCK_600_200 0x00000050
#define MSAR_ARMDDRCLCK_800_200 0x00000070
#define FTDLL_DDR1_166MHZ 0x0047F001
#define FTDLL_DDR1_200MHZ 0x0044D001
/*
* Low-level init happens right after start.S has switched to SVC32,
* flushed and disabled caches and disabled MMU. We're still running
* from the boot chip select, so the first thing we should do is set
* up RAM for us to relocate into.
*/
.globl lowlevel_init
lowlevel_init:
/* Use 'r4 as the base for internal register accesses */
ldr r4, =ORION5X_REGS_PHY_BASE
/* move internal registers from the default 0xD0000000
* to their intended location, defined by SoC */
ldr r3, =0xD0000000
add r3, r3, #0x20000
str r4, [r3, #0x80]
/* Use R3 as the base for DRAM registers */
add r3, r4, #0x01000
/*DDR SDRAM Initialization Control */
ldr r6, =0x00000001
str r6, [r3, #0x480]
/* Use R3 as the base for PCI registers */
add r3, r4, #0x31000
/* Disable arbiter */
ldr r6, =0x00000030
str r6, [r3, #0xd00]
/* Use R3 as the base for DRAM registers */
add r3, r4, #0x01000
/* set all dram windows to 0 */
mov r6, #0
str r6, [r3, #0x504]
str r6, [r3, #0x50C]
str r6, [r3, #0x514]
str r6, [r3, #0x51C]
/* 1) Configure SDRAM */
ldr r6, =SDRAM_CONFIG
str r6, [r3, #0x400]
/* 2) Set SDRAM Control reg */
ldr r6, =SDRAM_CONTROL
str r6, [r3, #0x404]
/* 3) Write SDRAM address control register */
ldr r6, =SDRAM_ADDR_CTRL
str r6, [r3, #0x410]
/* 4) Write SDRAM bank 0 size register */
ldr r6, =SDRAM_BANK0_SIZE
str r6, [r3, #0x504]
/* keep other banks disabled */
/* 5) Write SDRAM open pages control register */
ldr r6, =SDRAM_OPEN_PAGE_EN
str r6, [r3, #0x414]
/* 6) Write SDRAM timing Low register */
ldr r6, =SDRAM_TIME_CTRL_LOW
str r6, [r3, #0x408]
/* 7) Write SDRAM timing High register */
ldr r6, =SDRAM_TIME_CTRL_HI
str r6, [r3, #0x40C]
/* 8) Write SDRAM mode register */
/* The CPU must not attempt to change the SDRAM Mode register setting */
/* prior to DRAM controller completion of the DRAM initialization */
/* sequence. To guarantee this restriction, it is recommended that */
/* the CPU sets the SDRAM Operation register to NOP command, performs */
/* read polling until the register is back in Normal operation value, */
/* and then sets SDRAM Mode register to its new value. */
/* 8.1 write 'nop' to SDRAM operation */
ldr r6, =SDRAM_OP_NOP
str r6, [r3, #0x418]
/* 8.2 poll SDRAM operation until back in 'normal' mode. */
1:
ldr r6, [r3, #0x418]
cmp r6, #0
bne 1b
/* 8.3 Now its safe to write new value to SDRAM Mode register */
ldr r6, =SDRAM_MODE
str r6, [r3, #0x41C]
/* 8.4 Set new mode */
ldr r6, =SDRAM_OP_SETMODE
str r6, [r3, #0x418]
/* 8.5 poll SDRAM operation until back in 'normal' mode. */
2:
ldr r6, [r3, #0x418]
cmp r6, #0
bne 2b
/* DDR SDRAM Address/Control Pads Calibration */
ldr r6, [r3, #0x4C0]
/* Set Bit [31] to make the register writable */
orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
str r6, [r3, #0x4C0]
bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
bic r6, r6, #SDRAM_PAD_CTRL_TUNE_EN
bic r6, r6, #SDRAM_PAD_CTRL_DRVN_MASK
bic r6, r6, #SDRAM_PAD_CTRL_DRVP_MASK
/* Get the final N locked value of driving strength [22:17] */
mov r1, r6
mov r1, r1, LSL #9
mov r1, r1, LSR #26 /* r1[5:0]<DrvN> = r3[22:17]<LockN> */
orr r1, r1, r1, LSL #6 /* r1[11:6]<DrvP> = r1[5:0]<DrvN> */
/* Write to both <DrvN> bits [5:0] and <DrvP> bits [11:6] */
orr r6, r6, r1
str r6, [r3, #0x4C0]
/* DDR SDRAM Data Pads Calibration */
ldr r6, [r3, #0x4C4]
/* Set Bit [31] to make the register writable */
orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
str r6, [r3, #0x4C4]
bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
bic r6, r6, #SDRAM_PAD_CTRL_TUNE_EN
bic r6, r6, #SDRAM_PAD_CTRL_DRVN_MASK
bic r6, r6, #SDRAM_PAD_CTRL_DRVP_MASK
/* Get the final N locked value of driving strength [22:17] */
mov r1, r6
mov r1, r1, LSL #9
mov r1, r1, LSR #26
orr r1, r1, r1, LSL #6 /* r1[5:0] = r3[22:17]<LockN> */
/* Write to both <DrvN> bits [5:0] and <DrvP> bits [11:6] */
orr r6, r6, r1
str r6, [r3, #0x4C4]
/* Implement Guideline (GL# MEM-3) Drive Strength Value */
/* Relevant for: 88F5181-A1/B0/B1 and 88F5281-A0/B0 */
ldr r1, =DDR1_PAD_STRENGTH_DEFAULT
/* Enable writes to DDR SDRAM Addr/Ctrl Pads Calibration register */
ldr r6, [r3, #0x4C0]
orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
str r6, [r3, #0x4C0]
/* Correct strength and disable writes again */
bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
bic r6, r6, #SDRAM_PAD_CTRL_DRV_STR_MASK
orr r6, r6, r1
str r6, [r3, #0x4C0]
/* Enable writes to DDR SDRAM Data Pads Calibration register */
ldr r6, [r3, #0x4C4]
orr r6, r6, #SDRAM_PAD_CTRL_WR_EN
str r6, [r3, #0x4C4]
/* Correct strength and disable writes again */
bic r6, r6, #SDRAM_PAD_CTRL_DRV_STR_MASK
bic r6, r6, #SDRAM_PAD_CTRL_WR_EN
orr r6, r6, r1
str r6, [r3, #0x4C4]
/* Implement Guideline (GL# MEM-4) DQS Reference Delay Tuning */
/* Relevant for: 88F5181-A1/B0/B1 and 88F5281-A0/B0 */
/* Get the "sample on reset" register for the DDR frequancy */
ldr r3, =0x10000
ldr r6, [r3, #0x010]
ldr r1, =MSAR_ARMDDRCLCK_MASK
and r1, r6, r1
ldr r6, =FTDLL_DDR1_166MHZ
cmp r1, #MSAR_ARMDDRCLCK_333_167
beq 3f
cmp r1, #MSAR_ARMDDRCLCK_500_167
beq 3f
cmp r1, #MSAR_ARMDDRCLCK_667_167
beq 3f
ldr r6, =FTDLL_DDR1_200MHZ
cmp r1, #MSAR_ARMDDRCLCK_400_200_1
beq 3f
cmp r1, #MSAR_ARMDDRCLCK_400_200
beq 3f
cmp r1, #MSAR_ARMDDRCLCK_600_200
beq 3f
cmp r1, #MSAR_ARMDDRCLCK_800_200
beq 3f
ldr r6, =0
3:
/* Use R3 as the base for DRAM registers */
add r3, r4, #0x01000
ldr r2, [r3, #0x484]
orr r2, r2, r6
str r2, [r3, #0x484]
/* Return to U-boot via saved link register */
mov pc, lr