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Diffstat (limited to 'board/ns9750dev/lowlevel_init.S')
| -rw-r--r-- | board/ns9750dev/lowlevel_init.S | 298 |
1 files changed, 298 insertions, 0 deletions
diff --git a/board/ns9750dev/lowlevel_init.S b/board/ns9750dev/lowlevel_init.S new file mode 100644 index 0000000..3a09786 --- /dev/null +++ b/board/ns9750dev/lowlevel_init.S @@ -0,0 +1,298 @@ +/* + * Board specific setup info + * + * (C) Copyright 2003 + * Texas Instruments, <www.ti.com> + * Kshitij Gupta <Kshitij@ti.com> + * + * Modified for the NS9750 DevBoard by + * (C) Copyright 2004 by FS Forth-Systeme GmbH. + * Markus Pietrek <mpietrek@fsforth.de> + * @References: [1] NS9750 Hardware Reference/December 2003 + * [2] ns9750_a.cmd from MAJIC configuration + * + * 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> + +#if defined(CONFIG_NS9750DEV) +# ifndef CONFIG_SKIP_LOWLEVEL_INIT +# include <./ns9750_sys.h> +# include <./ns9750_mem.h> +# endif +#endif + +/*********************************************************************** + * @Function: write_register_block + * @Return: nothing + * @Descr: Copies the register block of register_offset:register value to + * the registers at base r0. The block is assumed to start in RAM at r1 + * and end at r2. The linked RAM base address of U-Boot is assumed to be + * in r5 while the ROM base address we are running from is r6 + * Uses r3 and r4 as tempory registers + ***********************************************************************/ + +.macro write_register_block + @@ map the addresses to high memory + sub r1, r1, r5 + add r1, r1, r6 + sub r2, r2, r5 + add r2, r2, r6 + + @@ copy all +1: + @@ Write register/value pair starting at [r1] to register base r0 + ldr r3, [r1], #4 + ldr r4, [r1], #4 + str r4, [r0,r3] + cmp r1, r2 + blt 1b +.endm + +_TEXT_BASE: + .word TEXT_BASE @ sdram load addr from config.mk +_PHYS_FLASH: + .word PHYS_FLASH_1 @ real flash address (without mirroring) +_CAS_LATENCY: + .word 0x00022000 @ for CAS2 latency + +#ifndef CONFIG_SKIP_LOWLEVEL_INIT +.globl lowlevel_init +lowlevel_init: + + /* U-Boot may be linked to RAM at 0x780000. But this code will run in + flash from 0x0. But in order to enable RAM we have to disable the + mirror bit, therefore we have to jump to our real flash address + beginning at PHYS_FLASH_1 (CS4 Base). Therefore, + _run_at_real_flash_address may be 0x500003b0 while be linked to + 0x7803b0. So we must modify our linked addresses */ + + @@ branch to high memory address, away from 0x0 + ldr r5, _TEXT_BASE + ldr r6, _PHYS_FLASH + ldr r0, =_run_at_real_flash_address + sub r0, r0, r5 + add r0, r0, r6 + mov pc, r0 + nop @ for pipelining + +_run_at_real_flash_address: + @@ now we are running > PHYS_FLASH_1, safe to enable memory controller + + @@ Write Memory Configuration Registers + + ldr r0, _NS9750_MEM_MODULE_BASE + ldr r1, =_MEM_CONFIG_START + ldr r2, =_MEM_CONFIG_END + + write_register_block + + @@ Give SDRAM some time to settle + @@ @TODO. According to [2] it should be 2 AHB cycles. Check + + ldr r1, =0x50 +_sdram_settle: + subs r1, r1, #1 + bne _sdram_settle + +_enable_mappings: + @@ Enable SDRAM Mode + + ldr r1, =_MEM_MODE_START + ldr r2, =_MEM_MODE_END + + write_register_block + + ldr r3, _CAS_LATENCY @ perform one read from SDRAM + ldr r3, [r3] + + @@ Enable SDRAM and memory mappings + + ldr r1, =_MEM_ENABLE_START + ldr r2, =_MEM_ENABLE_END + + write_register_block + + @@ Activate AHB monitor + + ldr r0, =NS9750_SYS_MODULE_BASE + ldr r1, =_AHB_MONITOR_START + ldr r2, =_AHB_MONITOR_END + + write_register_block +_relocate_lr: + /* lr and ip (from cpu_init_crit) are still based on 0x0, relocate it to + PHYS_FLASH. */ + mov r1, ip + add r1, r1, r6 + mov ip, r1 + + mov r1, lr + add r1, r1, r6 + mov lr, r1 + + @@ back to arch calling code + mov pc, lr + + .ltorg + +_NS9750_MEM_MODULE_BASE: + .word NS9750_MEM_MODULE_BASE + +_MEM_CONFIG_START: + /* Table of 2 32bit entries. First word is register address offset + relative to NS9750_MEM_MODULE_BASE, second one is value. They are + written in order of appearance */ + + @@ Register values taken from [2] + .word NS9750_MEM_CTRL + .word NS9750_MEM_CTRL_E + + .word NS9750_MEM_DYN_REFRESH + .word (0x6 & NS9750_MEM_DYN_REFRESH_MA) + + .word NS9750_MEM_DYN_READ_CFG + .word (0x1 & NS9750_MEM_DYN_READ_CFG_MA) + + .word NS9750_MEM_DYN_TRP + .word (0x1 & NS9750_MEM_DYN_TRP_MA) + + .word NS9750_MEM_DYN_TRAS + .word (0x4 & NS9750_MEM_DYN_TRAS_MA) + + .word NS9750_MEM_DYN_TAPR + .word (0x1 & NS9750_MEM_DYN_TRAS_MA) + + .word NS9750_MEM_DYN_TDAL + .word (0x5 & NS9750_MEM_DYN_TDAL_MA) + + .word NS9750_MEM_DYN_TWR + .word (0x1 & NS9750_MEM_DYN_TWR_MA) + + .word NS9750_MEM_DYN_TRC + .word (0x6 & NS9750_MEM_DYN_TRC_MA) + + .word NS9750_MEM_DYN_TRFC + .word (0x6 & NS9750_MEM_DYN_TRFC_MA) + + .word NS9750_MEM_DYN_TRRD + .word (0x1 & NS9750_MEM_DYN_TRRD_MA) + + .word NS9750_MEM_DYN_TMRD + .word (0x1 & NS9750_MEM_DYN_TMRD_MA) + + @@ CS 4 + .word NS9750_MEM_DYN_CFG(0) + .word (NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) + + .word NS9750_MEM_DYN_RAS_CAS(0) + .word ((0x200 & NS9750_MEM_DYN_RAS_CAS_CAS_MA) | \ + (0x03 & NS9750_MEM_DYN_RAS_CAS_RAS_MA)) + + @@ CS 5 + .word NS9750_MEM_DYN_CFG(1) + .word (NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) + + .word NS9750_MEM_DYN_RAS_CAS(1) + .word ((0x200 & NS9750_MEM_DYN_RAS_CAS_CAS_MA) | \ + (0x03 & NS9750_MEM_DYN_RAS_CAS_RAS_MA)) + + @@ CS 6 + .word NS9750_MEM_DYN_CFG(2) + .word (NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) + + .word NS9750_MEM_DYN_RAS_CAS(2) + .word ((0x200 & NS9750_MEM_DYN_RAS_CAS_CAS_MA) | \ + (0x03 & NS9750_MEM_DYN_RAS_CAS_RAS_MA)) + + @@ CS 7 + .word NS9750_MEM_DYN_CFG(3) + .word (NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) + + .word NS9750_MEM_DYN_RAS_CAS(3) + .word ((0x200 & NS9750_MEM_DYN_RAS_CAS_CAS_MA) | \ + (0x03 & NS9750_MEM_DYN_RAS_CAS_RAS_MA)) + + .word NS9750_MEM_DYN_CTRL + .word (NS9750_MEM_DYN_CTRL_I_PALL | \ + NS9750_MEM_DYN_CTRL_SR | \ + NS9750_MEM_DYN_CTRL_CE ) + + .word NS9750_MEM_DYN_REFRESH + .word (0x1 & NS9750_MEM_DYN_REFRESH_MA) + @@ No further register settings after refresh +_MEM_CONFIG_END: + +_MEM_MODE_START: + .word NS9750_MEM_DYN_REFRESH + .word (0x30 & NS9750_MEM_DYN_REFRESH_MA) + + .word NS9750_MEM_DYN_CTRL + .word (NS9750_MEM_DYN_CTRL_I_MODE | \ + NS9750_MEM_DYN_CTRL_SR | \ + NS9750_MEM_DYN_CTRL_CE ) +_MEM_MODE_END: + +_MEM_ENABLE_START: + .word NS9750_MEM_DYN_CTRL + .word (NS9750_MEM_DYN_CTRL_I_NORMAL | \ + NS9750_MEM_DYN_CTRL_SR | \ + NS9750_MEM_DYN_CTRL_CE ) + + @@ CS 4 + .word NS9750_MEM_DYN_CFG(0) + .word (NS9750_MEM_DYN_CFG_BDMC | \ + NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) + + @@ CS 5 + .word NS9750_MEM_DYN_CFG(1) + .word (NS9750_MEM_DYN_CFG_BDMC | \ + NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) + + @@ CS 6 + .word NS9750_MEM_DYN_CFG(2) + .word (NS9750_MEM_DYN_CFG_BDMC | \ + NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) + + @@ CS 7 + .word NS9750_MEM_DYN_CFG(3) + .word (NS9750_MEM_DYN_CFG_BDMC | \ + NS9750_MEM_DYN_CFG_AM | \ + (0x280 & NS9750_MEM_DYN_CFG_AM_MA)) +_MEM_ENABLE_END: + +_AHB_MONITOR_START: + .word NS9750_SYS_AHB_TIMEOUT + .word 0x01000100 @ @TODO not calculated yet + + .word NS9750_SYS_AHB_MON + .word (NS9750_SYS_AHB_MON_BMTC_GEN_IRQ | \ + NS9750_SYS_AHB_MON_BATC_GEN_IRQ) +_AHB_MONITOR_END: + +#endif /* CONFIG_SKIP_LOWLEVEL_INIT */ |