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+/*
+ * Copyright (c) 2004 Cucy Systems (http://www.cucy.com)
+ * Curt Brune <curt@cucy.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., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+
+#include <config.h>
+#include <version.h>
+#include <asm/hardware.h>
+
+/***********************************************************************
+ * Configure Memory Map
+ *
+ * This memory map allows us to relocate from FLASH to SRAM. After
+ * power-on reset the CPU only knows about the FLASH memory at address
+ * 0x00000000. After lowlevel_init completes the memory map will be:
+ *
+ * Memory Addr
+ * 0x00000000
+ * to 8MB SRAM (U5) -- 8MB Map
+ * 0x00800000
+ *
+ * 0x01000000
+ * to 2MB Flash @ 0x00000000 (U7) -- 2MB Map
+ * 0x01200000
+ *
+ * 0x02000000
+ * to 512KB Flash @ 0x02000000 (U9) -- 2MB Map
+ * 0x02080000
+ *
+ * Load all 12 memory registers with the STMIA instruction since
+ * memory access is disabled once these registers are written. The
+ * last register written re-enables memory access. For more info see
+ * the user's manual for the S3C4510B, available from Samsung's web
+ * site. Search for part number "S3C4510B".
+ *
+ ***********************************************************************/
+
+.globl lowlevel_init
+lowlevel_init:
+
+ /* preserve the temp register (r12 AKA ip) and remap it. */
+ ldr r1, =SRAM_BASE+0xC
+ add r0, r12, #0x01000000
+ str r0, [r1]
+
+ /* remap the link register for when we return */
+ add lr, lr, #0x01000000
+
+ /* store a short program in the on chip SRAM, which is
+ * unaffected when remapping memory. Note the cache must be
+ * disabled for the on chip SRAM to be available.
+ */
+ ldr r1, =SRAM_BASE
+ ldr r0, =0xe8801ffe /* stmia r0, {r1-r12} */
+ str r0, [r1]
+ add r1, r1, #4
+ ldr r0, =0xe59fc000 /* ldr r12, [pc, #0] */
+ str r0, [r1]
+ add r1, r1, #4
+ ldr r0, =0xe1a0f00e /* mov pc, lr */
+ str r0, [r1]
+
+ adr r0, memory_map_data
+ ldmia r0, {r1-r12}
+ ldr r0, =REG_EXTDBWTH
+
+ ldr pc, =SRAM_BASE
+
+.globl reset_cpu
+reset_cpu:
+ /*
+ * reset the cpu by re-mapping FLASH 0 to 0x0 and jumping to
+ * address 0x0. We accomplish this by storing a few
+ * instructions into the on chip SRAM (8KB) and run from
+ * there. Note the cache must be disabled for the on chip
+ * SRAM to be available.
+ *
+ * load r2 with REG_ROMCON0
+ * load r3 with 0x12040060 configure FLASH bank 0 @ 0x00000000
+ * load r4 with REG_DRAMCON0
+ * load r5 with 0x08000380 configure RAM bank 0 @ 0x01000000
+ * load r6 with REG_REFEXTCON
+ * load r7 with 0x9c218360
+ * load r8 with 0x0
+ * store str r3,[r2] @ SRAM_BASE
+ * store str r5,[r4] @ SRAM_BASE + 0x4
+ * store str r7,[r6] @ SRAM_BASE + 0x8
+ * store mov pc,r8 @ SRAM_BASE + 0xC
+ * mov pc, SRAM_BASE
+ *
+ */
+
+ /* disable cache */
+ ldr r0, =REG_SYSCFG
+ ldr r1, =0x83ffffa0 /* cache-disabled */
+ str r1, [r0]
+
+ ldr r2, =REG_ROMCON0
+ ldr r3, =0x02000060 /* Bank0 2MB FLASH @ 0x00000000 */
+ ldr r4, =REG_DRAMCON0
+ ldr r5, =0x18040380 /* DRAM0 8MB SRAM @ 0x01000000 */
+ ldr r6, =REG_REFEXTCON
+ ldr r7, =0xce278360
+ ldr r8, =0x00000000
+ ldr r1, =SRAM_BASE
+ ldr r0, =0xe5823000 /* str r3, [r2] */
+ str r0, [r1]
+ ldr r1, =SRAM_BASE+4
+ ldr r0, =0xe5845000 /* str r5, [r4] */
+ str r0, [r1]
+ ldr r1, =SRAM_BASE+8
+ ldr r0, =0xe5867000 /* str r7, [r6] */
+ str r0, [r1]
+ ldr r1, =SRAM_BASE+0xC
+ ldr r0, =0xe1a0f008 /* mov pc, r8 */
+ str r0, [r1]
+ ldr r1, =SRAM_BASE
+ mov pc, r1
+
+ /* never return */
+
+/************************************************************************
+ * Below are twelve 32-bit values for the twelve memory registers of
+ * the system manager, starting with register REG_EXTDBWTH.
+ ***********************************************************************/
+memory_map_data:
+ .long 0x00f03005 /* memory widths */
+ .long 0x12040060 /* Bank0 2MB FLASH @ 0x01000000 */
+ .long 0x22080060 /* Bank1 512KB FLASH @ 0x02000000 */
+ .long 0x00000000
+ .long 0x00000000
+ .long 0x00000000
+ .long 0x00000000
+ .long 0x08000380 /* DRAM0 8MB SRAM @ 0x00000000 */
+ .long 0x00000000
+ .long 0x00000000
+ .long 0x00000000
+ .long 0x9c218360 /* enable memory */