/* * Initialization stuff - taken from hermit * (C) Copyright 2005 Rowel Atienza <rowel@diwalabs.com> * Armadillo board HT1070 * * 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> /* some parameters for the board */ /* setting up the memory */ #define SRAM_START 0x60000000 #define SRAM_SIZE 0x0000c000 .globl lowlevel_init lowlevel_init: mov r0, #0x70 /* 32-bit code + data, MMU mandatory */ mcr p15, 0, r0, c1, c0, 0 /* MMU init */ mov r0, #0 mcr p15, 0, r0, c7, c7, 0 /* flush v3/v4 cache */ mcr p15, 0, r0, c8, c7, 0 /* flush v4 TLB */ mov r0, #0x80000000 /* I/O base */ mov r1, #0x6 /* CLKCTL_73 in SYSCON3 */ add r2, r0, #0x2200 /* address of SYSCON3 in r2 */ str r1, [r2] /* set clock speed to 73.728 MHz */ mov r1, #0x81 /* 64KHz DRAM refresh period */ str r1, [r0, #0x200] /* set DRFPR */ mov r1, #0x500 /* permanent enable, 16bits wide */ add r1, r1, #0x42 /* 128Mbit, CAS lat = 2 SDRAM */ add r2, r0, #0x2300 /* load address in r2 */ str r1, [r2] mov r1, #0x100 /* SDRAM refresh rate */ add r2, r0, #0x2340 /* load address in r2 */ str r1, [r2] mov sp, #SRAM_START /* init stack pointer */ add sp, sp, #SRAM_SIZE /* everything is fine now */ mov pc, lr