Bartlomiej Sieka | 8ff81c6 | 2006-12-20 00:27:32 +0100 | [diff] [blame^] | 1 | /* |
| 2 | * (C) Copyright 2000-2006 |
| 3 | * Wolfgang Denk, DENX Software Engineering, wd@denx.de. |
| 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 | #include <common.h> |
| 25 | #include <asm/m5271.h> |
| 26 | #include <asm/immap_5271.h> |
| 27 | |
| 28 | int checkboard (void) { |
| 29 | puts ("Board: iDMR\n"); |
| 30 | return 0; |
| 31 | }; |
| 32 | |
| 33 | long int initdram (int board_type) { |
| 34 | int i; |
| 35 | |
| 36 | /* |
| 37 | * After reset, CS0 is configured to cover entire address space. We |
| 38 | * need to configure it to its proper values, so that writes to |
| 39 | * CFG_SDRAM_BASE and vicinity during SDRAM controller setup below do |
| 40 | * now fall under CS0 (see 16.3.1 of the MCF5271 Reference Manual). |
| 41 | */ |
| 42 | |
| 43 | /* Flash chipselect, CS0 */ |
| 44 | /* ;CSAR0: Flash at 0xFF800000 */ |
| 45 | mbar_writeShort(0x0080, 0xFF80); |
| 46 | |
| 47 | /* CSCR0: Flash 6 waits, 16bit */ |
| 48 | mbar_writeShort(0x008A, 0x1980); |
| 49 | |
| 50 | /* CSMR0: Flash 8MB, R/W, valid */ |
| 51 | mbar_writeLong(0x0084, 0x007F0001); |
| 52 | |
| 53 | |
| 54 | /* |
| 55 | * SDRAM configuration proper |
| 56 | */ |
| 57 | |
| 58 | /* |
| 59 | * Address/Data Pin Assignment Reg.: enable address lines 23-21; do |
| 60 | * not enable data pins D[15:0], as we have 16 bit port to SDRAM |
| 61 | */ |
| 62 | mbar_writeByte(MCF_GPIO_PAR_AD, |
| 63 | MCF_GPIO_AD_ADDR23 | |
| 64 | MCF_GPIO_AD_ADDR22 | |
| 65 | MCF_GPIO_AD_ADDR21); |
| 66 | |
| 67 | /* No need to configure BS pins - reset values are OK */ |
| 68 | |
| 69 | /* Chip Select Pin Assignment Reg.: set CS[1-7] to GPIO */ |
| 70 | mbar_writeByte(MCF_GPIO_PAR_CS, 0x00); |
| 71 | |
| 72 | /* SDRAM Control Pin Assignment Reg. */ |
| 73 | mbar_writeByte(MCF_GPIO_PAR_SDRAM, |
| 74 | MCF_GPIO_SDRAM_CSSDCS_00 | /* no matter: PAR_CS=0 */ |
| 75 | MCF_GPIO_SDRAM_SDWE | |
| 76 | MCF_GPIO_SDRAM_SCAS | |
| 77 | MCF_GPIO_SDRAM_SRAS | |
| 78 | MCF_GPIO_SDRAM_SCKE | |
| 79 | MCF_GPIO_SDRAM_SDCS_01); |
| 80 | |
| 81 | /* |
| 82 | * Wait 100us. We run the bus at 50Mhz, one cycle is 20ns. So 5 |
| 83 | * iterations will do, but we do 10 just to be safe. |
| 84 | */ |
| 85 | for (i = 0; i < 10; ++i) |
| 86 | asm(" nop"); |
| 87 | |
| 88 | |
| 89 | /* 1. Initialize DRAM Control Register: DCR */ |
| 90 | mbar_writeShort(MCF_SDRAMC_DCR, |
| 91 | MCF_SDRAMC_DCR_RTIM(0x10) | /* 65ns */ |
| 92 | MCF_SDRAMC_DCR_RC(0x60)); /* 1562 cycles */ |
| 93 | |
| 94 | |
| 95 | /* |
| 96 | * 2. Initialize DACR0 |
| 97 | * |
| 98 | * CL: 11 (CL=3: 0x03, 0x02; CL=2: 0x1) |
| 99 | * CBM: cmd at A20, bank select bits 21 and up |
| 100 | * PS: 16 bit |
| 101 | */ |
| 102 | mbar_writeLong(MCF_SDRAMC_DACR0, |
| 103 | MCF_SDRAMC_DACRn_BA(CFG_SDRAM_BASE>>18) | |
| 104 | MCF_SDRAMC_DACRn_BA(0x00) | |
| 105 | MCF_SDRAMC_DACRn_CASL(0x03) | |
| 106 | MCF_SDRAMC_DACRn_CBM(0x03) | |
| 107 | MCF_SDRAMC_DACRn_PS(0x03)); |
| 108 | |
| 109 | /* Initialize DMR0 */ |
| 110 | mbar_writeLong(MCF_SDRAMC_DMR0, |
| 111 | MCF_SDRAMC_DMRn_BAM_16M | |
| 112 | MCF_SDRAMC_DMRn_V); |
| 113 | |
| 114 | |
| 115 | /* 3. Set IP bit in DACR to initiate PALL command */ |
| 116 | mbar_writeLong(MCF_SDRAMC_DACR0, |
| 117 | mbar_readLong(MCF_SDRAMC_DACR0) | |
| 118 | MCF_SDRAMC_DACRn_IP); |
| 119 | |
| 120 | /* Write to this block to initiate precharge */ |
| 121 | *(volatile u16 *)(CFG_SDRAM_BASE) = 0xa5a5; |
| 122 | |
| 123 | /* |
| 124 | * Wait at least 20ns to allow banks to precharge (t_RP = 20ns). We |
| 125 | * wait a wee longer, just to be safe. |
| 126 | */ |
| 127 | for (i = 0; i < 5; ++i) |
| 128 | asm(" nop"); |
| 129 | |
| 130 | |
| 131 | /* 4. Set RE bit in DACR */ |
| 132 | mbar_writeLong(MCF_SDRAMC_DACR0, |
| 133 | mbar_readLong(MCF_SDRAMC_DACR0) | |
| 134 | MCF_SDRAMC_DACRn_RE); |
| 135 | |
| 136 | /* |
| 137 | * Wait for at least 8 auto refresh cycles to occur, i.e. at least |
| 138 | * 781 bus cycles. |
| 139 | */ |
| 140 | for (i = 0; i < 1000; ++i) |
| 141 | asm(" nop"); |
| 142 | |
| 143 | /* Finish the configuration by issuing the MRS */ |
| 144 | mbar_writeLong(MCF_SDRAMC_DACR0, |
| 145 | mbar_readLong(MCF_SDRAMC_DACR0) | |
| 146 | MCF_SDRAMC_DACRn_MRS); |
| 147 | |
| 148 | /* |
| 149 | * Write to the SDRAM Mode Register A0-A11 = 0x400 |
| 150 | * |
| 151 | * Write Burst Mode = Programmed Burst Length |
| 152 | * Op Mode = Standard Op |
| 153 | * CAS Latency = 3 |
| 154 | * Burst Type = Sequential |
| 155 | * Burst Length = 1 |
| 156 | */ |
| 157 | *(volatile u32 *)(CFG_SDRAM_BASE + 0x1800) = 0xa5a5a5a5; |
| 158 | |
| 159 | return CFG_SDRAM_SIZE * 1024 * 1024; |
| 160 | }; |
| 161 | |
| 162 | |
| 163 | int testdram (void) { |
| 164 | |
| 165 | /* TODO: XXX XXX XXX */ |
| 166 | printf ("DRAM test not implemented!\n"); |
| 167 | |
| 168 | return (0); |
| 169 | } |