1 /*
2  * (C) Copyright 2000-2003
3  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
4  *
5  * Copyright (C) 2004-2007 Freescale Semiconductor, Inc.
6  * TsiChung Liew (Tsi-Chung.Liew@freescale.com)
7  *
8  * See file CREDITS for list of people who contributed to this
9  * project.
10  *
11  * This program is free software; you can redistribute it and/or
12  * modify it under the terms of the GNU General Public License as
13  * published by the Free Software Foundation; either version 2 of
14  * the License, or (at your option) any later version.
15  *
16  * This program is distributed in the hope that it will be useful,
17  * but WITHOUT ANY WARRANTY; without even the implied warranty of
18  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
19  * GNU General Public License for more details.
20  *
21  * You should have received a copy of the GNU General Public License
22  * along with this program; if not, write to the Free Software
23  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
24  * MA 02111-1307 USA
25  */
26 
27 #include <config.h>
28 #include <common.h>
29 #include <asm/immap.h>
30 
31 DECLARE_GLOBAL_DATA_PTR;
32 
33 int checkboard(void)
34 {
35 	puts("Board: ");
36 	puts("Freescale M5235 EVB\n");
37 	return 0;
38 };
39 
40 phys_size_t initdram(int board_type)
41 {
42 	volatile sdram_t *sdram = (volatile sdram_t *)(MMAP_SDRAM);
43 	volatile gpio_t *gpio = (volatile gpio_t *)(MMAP_GPIO);
44 	u32 dramsize, i, dramclk;
45 
46 	/*
47 	 * When booting from external Flash, the port-size is less than
48 	 * the port-size of SDRAM.  In this case it is necessary to enable
49 	 * Data[15:0] on Port Address/Data.
50 	 */
51 	gpio->par_ad =
52 	    GPIO_PAR_AD_ADDR23 | GPIO_PAR_AD_ADDR22 | GPIO_PAR_AD_ADDR21 |
53 	    GPIO_PAR_AD_DATAL;
54 
55 	/* Initialize PAR to enable SDRAM signals */
56 	gpio->par_sdram =
57 	    GPIO_PAR_SDRAM_SDWE | GPIO_PAR_SDRAM_SCAS | GPIO_PAR_SDRAM_SRAS |
58 	    GPIO_PAR_SDRAM_SCKE | GPIO_PAR_SDRAM_SDCS(3);
59 
60 	dramsize = CONFIG_SYS_SDRAM_SIZE * 0x100000;
61 	for (i = 0x13; i < 0x20; i++) {
62 		if (dramsize == (1 << i))
63 			break;
64 	}
65 	i--;
66 
67 	if (!(sdram->dacr0 & SDRAMC_DARCn_RE)) {
68 		dramclk = gd->bus_clk / (CONFIG_SYS_HZ * CONFIG_SYS_HZ);
69 
70 		/* Initialize DRAM Control Register: DCR */
71 		sdram->dcr = SDRAMC_DCR_RTIM_9CLKS |
72 		    SDRAMC_DCR_RTIM_6CLKS | SDRAMC_DCR_RC((15 * dramclk) >> 4);
73 
74 		/* Initialize DACR0 */
75 		sdram->dacr0 =
76 		    SDRAMC_DARCn_BA(CONFIG_SYS_SDRAM_BASE) | SDRAMC_DARCn_CASL_C1 |
77 		    SDRAMC_DARCn_CBM_CMD20 | SDRAMC_DARCn_PS_32;
78 		asm("nop");
79 
80 		/* Initialize DMR0 */
81 		sdram->dmr0 = ((dramsize - 1) & 0xFFFC0000) | SDRAMC_DMRn_V;
82 		asm("nop");
83 
84 		/* Set IP (bit 3) in DACR */
85 		sdram->dacr0 |= SDRAMC_DARCn_IP;
86 
87 		/* Wait 30ns to allow banks to precharge */
88 		for (i = 0; i < 5; i++) {
89 			asm("nop");
90 		}
91 
92 		/* Write to this block to initiate precharge */
93 		*(u32 *) (CONFIG_SYS_SDRAM_BASE) = 0xA5A59696;
94 
95 		/*  Set RE (bit 15) in DACR */
96 		sdram->dacr0 |= SDRAMC_DARCn_RE;
97 
98 		/* Wait for at least 8 auto refresh cycles to occur */
99 		for (i = 0; i < 0x2000; i++) {
100 			asm("nop");
101 		}
102 
103 		/* Finish the configuration by issuing the MRS. */
104 		sdram->dacr0 |= SDRAMC_DARCn_IMRS;
105 		asm("nop");
106 
107 		/* Write to the SDRAM Mode Register */
108 		*(u32 *) (CONFIG_SYS_SDRAM_BASE + 0x400) = 0xA5A59696;
109 	}
110 
111 	return dramsize;
112 };
113 
114 int testdram(void)
115 {
116 	/* TODO: XXX XXX XXX */
117 	printf("DRAM test not implemented!\n");
118 
119 	return (0);
120 }
121