wdenk | f2140d5 | 2004-07-01 16:30:44 +0000 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (c) 2004 Cucy Systems (http://www.cucy.com) |
| 3 | * Curt Brune <curt@cucy.com> |
| 4 | * |
| 5 | * See file CREDITS for list of people who contributed to this |
| 6 | * project. |
| 7 | * |
| 8 | * This program is free software; you can redistribute it and/or |
| 9 | * modify it under the terms of the GNU General Public License as |
| 10 | * published by the Free Software Foundation; either version 2 of |
| 11 | * the License, or (at your option) any later version. |
| 12 | * |
| 13 | * This program is distributed in the hope that it will be useful, |
| 14 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 15 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 16 | * GNU General Public License for more details. |
| 17 | * |
| 18 | * You should have received a copy of the GNU General Public License |
| 19 | * along with this program; if not, write to the Free Software |
| 20 | * Foundation, Inc., 59 Temple Place, Suite 330, Boston, |
| 21 | * MA 02111-1307 USA |
| 22 | */ |
| 23 | |
| 24 | |
| 25 | #include <config.h> |
| 26 | #include <version.h> |
| 27 | #include <asm/hardware.h> |
| 28 | |
| 29 | /*********************************************************************** |
| 30 | * Configure Memory Map |
| 31 | * |
| 32 | * This memory map allows us to relocate from FLASH to SRAM. After |
| 33 | * power-on reset the CPU only knows about the FLASH memory at address |
| 34 | * 0x00000000. After memsetup completes the memory map will be: |
| 35 | * |
| 36 | * Memory Addr |
| 37 | * 0x00000000 |
| 38 | * to 8MB SRAM (U5) -- 8MB Map |
| 39 | * 0x00800000 |
| 40 | * |
| 41 | * 0x01000000 |
| 42 | * to 2MB Flash @ 0x00000000 (U7) -- 2MB Map |
| 43 | * 0x01200000 |
| 44 | * |
| 45 | * 0x02000000 |
| 46 | * to 512KB Flash @ 0x02000000 (U9) -- 2MB Map |
| 47 | * 0x02080000 |
| 48 | * |
| 49 | * Load all 12 memory registers with the STMIA instruction since |
| 50 | * memory access is disabled once these registers are written. The |
| 51 | * last register written re-enables memory access. For more info see |
| 52 | * the user's manual for the S3C4510B, available from Samsung's web |
| 53 | * site. Search for part number "S3C4510B". |
| 54 | * |
| 55 | ***********************************************************************/ |
| 56 | |
| 57 | .globl memsetup |
| 58 | memsetup: |
| 59 | |
| 60 | /* preserve the temp register (r12 AKA ip) and remap it. */ |
| 61 | ldr r1, =SRAM_BASE+0xC |
| 62 | add r0, r12, #0x01000000 |
| 63 | str r0, [r1] |
| 64 | |
| 65 | /* remap the link register for when we return */ |
| 66 | add lr, lr, #0x01000000 |
| 67 | |
| 68 | /* store a short program in the on chip SRAM, which is |
| 69 | * unaffected when remapping memory. Note the cache must be |
| 70 | * disabled for the on chip SRAM to be available. |
| 71 | */ |
| 72 | ldr r1, =SRAM_BASE |
| 73 | ldr r0, =0xe8801ffe /* stmia r0, {r1-r12} */ |
| 74 | str r0, [r1] |
| 75 | add r1, r1, #4 |
| 76 | ldr r0, =0xe59fc000 /* ldr r12, [pc, #0] */ |
| 77 | str r0, [r1] |
| 78 | add r1, r1, #4 |
| 79 | ldr r0, =0xe1a0f00e /* mov pc, lr */ |
| 80 | str r0, [r1] |
| 81 | |
| 82 | adr r0, memory_map_data |
| 83 | ldmia r0, {r1-r12} |
| 84 | ldr r0, =REG_EXTDBWTH |
| 85 | |
| 86 | ldr pc, =SRAM_BASE |
| 87 | |
| 88 | .globl reset_cpu |
| 89 | reset_cpu: |
| 90 | /* |
| 91 | * reset the cpu by re-mapping FLASH 0 to 0x0 and jumping to |
| 92 | * address 0x0. We accomplish this by storing a few |
| 93 | * instructions into the on chip SRAM (8KB) and run from |
| 94 | * there. Note the cache must be disabled for the on chip |
| 95 | * SRAM to be available. |
| 96 | * |
| 97 | * load r2 with REG_ROMCON0 |
| 98 | * load r3 with 0x12040060 configure FLASH bank 0 @ 0x00000000 |
| 99 | * load r4 with REG_DRAMCON0 |
| 100 | * load r5 with 0x08000380 configure RAM bank 0 @ 0x01000000 |
| 101 | * load r6 with REG_REFEXTCON |
| 102 | * load r7 with 0x9c218360 |
| 103 | * load r8 with 0x0 |
| 104 | * store str r3,[r2] @ SRAM_BASE |
| 105 | * store str r5,[r4] @ SRAM_BASE + 0x4 |
| 106 | * store str r7,[r6] @ SRAM_BASE + 0x8 |
| 107 | * store mov pc,r8 @ SRAM_BASE + 0xC |
| 108 | * mov pc, SRAM_BASE |
| 109 | * |
| 110 | */ |
| 111 | |
| 112 | /* disable cache */ |
| 113 | ldr r0, =REG_SYSCFG |
| 114 | ldr r1, =0x83ffffa0 /* cache-disabled */ |
| 115 | str r1, [r0] |
| 116 | |
| 117 | ldr r2, =REG_ROMCON0 |
| 118 | ldr r3, =0x02000060 /* Bank0 2MB FLASH @ 0x00000000 */ |
| 119 | ldr r4, =REG_DRAMCON0 |
| 120 | ldr r5, =0x18040380 /* DRAM0 8MB SRAM @ 0x01000000 */ |
| 121 | ldr r6, =REG_REFEXTCON |
| 122 | ldr r7, =0xce278360 |
| 123 | ldr r8, =0x00000000 |
| 124 | ldr r1, =SRAM_BASE |
| 125 | ldr r0, =0xe5823000 /* str r3, [r2] */ |
| 126 | str r0, [r1] |
| 127 | ldr r1, =SRAM_BASE+4 |
| 128 | ldr r0, =0xe5845000 /* str r5, [r4] */ |
| 129 | str r0, [r1] |
| 130 | ldr r1, =SRAM_BASE+8 |
| 131 | ldr r0, =0xe5867000 /* str r7, [r6] */ |
| 132 | str r0, [r1] |
| 133 | ldr r1, =SRAM_BASE+0xC |
| 134 | ldr r0, =0xe1a0f008 /* mov pc, r8 */ |
| 135 | str r0, [r1] |
| 136 | ldr r1, =SRAM_BASE |
| 137 | mov pc, r1 |
| 138 | |
| 139 | /* never return */ |
| 140 | |
| 141 | /************************************************************************ |
| 142 | * Below are twelve 32-bit values for the twelve memory registers of |
| 143 | * the system manager, starting with register REG_EXTDBWTH. |
| 144 | ***********************************************************************/ |
| 145 | memory_map_data: |
| 146 | .long 0x00f03005 /* memory widths */ |
| 147 | .long 0x12040060 /* Bank0 2MB FLASH @ 0x01000000 */ |
| 148 | .long 0x22080060 /* Bank1 512KB FLASH @ 0x02000000 */ |
| 149 | .long 0x00000000 |
| 150 | .long 0x00000000 |
| 151 | .long 0x00000000 |
| 152 | .long 0x00000000 |
| 153 | .long 0x08000380 /* DRAM0 8MB SRAM @ 0x00000000 */ |
| 154 | .long 0x00000000 |
| 155 | .long 0x00000000 |
| 156 | .long 0x00000000 |
| 157 | .long 0x9c218360 /* enable memory */ |