diff options
Diffstat (limited to 'board/karo/tx25/lowlevel_init.S')
| -rw-r--r-- | board/karo/tx25/lowlevel_init.S | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/board/karo/tx25/lowlevel_init.S b/board/karo/tx25/lowlevel_init.S new file mode 100644 index 0000000..823df10 --- /dev/null +++ b/board/karo/tx25/lowlevel_init.S @@ -0,0 +1,131 @@ +/* + * (C) Copyright 2009 DENX Software Engineering + * Author: John Rigby <jrigby@gmail.com> + * + * Based on U-Boot and RedBoot sources for several different i.mx + * platforms. + * + * 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 <asm/macro.h> + +.macro init_aips + write32 0x43f00000, 0x77777777 + write32 0x43f00004, 0x77777777 + write32 0x43f00000, 0x77777777 + write32 0x53f00004, 0x77777777 +.endm + +.macro init_max + write32 0x43f04000, 0x43210 + write32 0x43f04100, 0x43210 + write32 0x43f04200, 0x43210 + write32 0x43f04300, 0x43210 + write32 0x43f04400, 0x43210 + + write32 0x43f04010, 0x10 + write32 0x43f04110, 0x10 + write32 0x43f04210, 0x10 + write32 0x43f04310, 0x10 + write32 0x43f04410, 0x10 + + write32 0x43f04800, 0x0 + write32 0x43f04900, 0x0 + write32 0x43f04a00, 0x0 + write32 0x43f04b00, 0x0 + write32 0x43f04c00, 0x0 +.endm + +.macro init_m3if + write32 0xb8003000, 0x1 +.endm + +.macro init_clocks + /* + * clocks + * + * first enable CLKO debug output + * 0x40000000 enables the debug CLKO signal + * 0x05000000 sets CLKO divider to 6 + * 0x00600000 makes CLKO parent clk the USB clk + */ + write32 0x53f80064, 0x45600000 + write32 0x53f80008, 0x20034000 + + /* + * enable all implemented clocks in all three + * clock control registers + */ + write32 0x53f8000c, 0x1fffffff + write32 0x53f80010, 0xffffffff + write32 0x53f80014, 0xfdfff +.endm + +.macro init_ddrtype + /* + * ddr_type is 3.3v SDRAM + */ + write32 0x43fac454, 0x800 +.endm + +/* + * sdram controller init + */ +.macro init_sdram_bank bankaddr, ctl, cfg + ldr r0, =0xb8001000 + ldr r2, =\bankaddr + /* + * reset SDRAM controller + * then wait for initialization to complete + */ + ldr r1, =(1 << 1) + str r1, [r0, #0x10] +1: ldr r3, [r0, #0x10] + tst r3, #(1 << 31) + beq 1b + + ldr r1, =0x95728 + str r1, [r0, #\cfg] /* config */ + + ldr r1, =0x92116480 /* control | precharge */ + str r1, [r0, #\ctl] /* write command to controller */ + str r1, [r2, #0x400] /* command encoded in address */ + + ldr r1, =0xa2116480 /* auto refresh */ + str r1, [r0, #\ctl] + ldrb r3, [r2] /* read dram twice to auto refresh */ + ldrb r3, [r2] + + ldr r1, =0xb2116480 /* control | load mode */ + str r1, [r0, #\ctl] /* write command to controller */ + strb r1, [r2, #0x33] /* command encoded in address */ + + ldr r1, =0x82116480 /* control | normal (0)*/ + str r1, [r0, #\ctl] /* write command to controller */ +.endm + +.globl lowlevel_init +lowlevel_init: + init_aips + init_max + init_m3if + init_clocks + + init_sdram_bank 0x80000000, 0x0, 0x4 + + init_sdram_bank 0x90000000, 0x8, 0xc + mov pc, lr |