summaryrefslogtreecommitdiffstats
path: root/board/freescale/m5271evb/m5271evb.c
blob: 5981a2711a44274b430337577f510062ab14519c (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
/*
 * (C) Copyright 2000-2006
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

#include <common.h>
#include <asm/immap.h>

int checkboard (void) {
	puts ("Board: Freescale M5271EVB\n");
	return 0;
};

phys_size_t initdram (int board_type) {

	int i;

	/* Enable Address lines 23-21 and lower 16bits of data path */
	mbar_writeByte(MCF_GPIO_PAR_AD, MCF_GPIO_AD_ADDR23 |
			MCF_GPIO_AD_ADDR22 | MCF_GPIO_AD_ADDR21 |
			MCF_GPIO_AD_DATAL);

	/* Set CS2 pin to be SD_CS0 */
	mbar_writeByte(MCF_GPIO_PAR_CS, mbar_readByte(MCF_GPIO_PAR_CS)
			| MCF_GPIO_PAR_CS_PAR_CS2);

	/* Configure SDRAM Control Pin Assignemnt Register */
	mbar_writeByte(MCF_GPIO_PAR_SDRAM, MCF_GPIO_SDRAM_CSSDCS_00 |
			MCF_GPIO_SDRAM_SDWE | MCF_GPIO_SDRAM_SCAS |
			MCF_GPIO_SDRAM_SRAS | MCF_GPIO_SDRAM_SCKE |
			MCF_GPIO_SDRAM_SDCS_11);
	asm(" nop");

	/*
	 * Check to see if the SDRAM has already been initialized
	 * by a run control tool
	 */
	if (!(mbar_readLong(MCF_SDRAMC_DACR0) & MCF_SDRAMC_DACRn_RE)) {
		/* Initialize DRAM Control Register: DCR */
		mbar_writeShort(MCF_SDRAMC_DCR,
				MCF_SDRAMC_DCR_RTIM(2)
				| MCF_SDRAMC_DCR_RC(0x2E));
		asm(" nop");

		/*
		 * Initialize DACR0
		 *
		 * CASL: 01
		 * CBM: cmd at A20, bank select bits 21 and up
		 * PS: 32bit port size
		 */
		mbar_writeLong(MCF_SDRAMC_DACR0,
				MCF_SDRAMC_DACRn_BA(CONFIG_SYS_SDRAM_BASE>>18)
				| MCF_SDRAMC_DACRn_CASL(1)
				| MCF_SDRAMC_DACRn_CBM(3)
				| MCF_SDRAMC_DACRn_PS(0));
		asm(" nop");

		/* Initialize DMR0 */
		mbar_writeLong(MCF_SDRAMC_DMR0,
				MCF_SDRAMC_DMRn_BAM_16M
				| MCF_SDRAMC_DMRn_V);
		asm(" nop");

		/* Set IP bit in DACR */
		mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
				| MCF_SDRAMC_DACRn_IP);
		asm(" nop");

		/* Wait at least 20ns to allow banks to precharge */
		for (i = 0; i < 5; i++)
			asm(" nop");

		/* Write to this block to initiate precharge */
		*(u32 *)(CONFIG_SYS_SDRAM_BASE) = 0xa5a5a5a5;
		asm(" nop");

		/* Set RE bit in DACR */
		mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
				| MCF_SDRAMC_DACRn_RE);

		/* Wait for at least 8 auto refresh cycles to occur */
		for (i = 0; i < 2000; i++)
			asm(" nop");

		/* Finish the configuration by issuing the MRS */
		mbar_writeLong(MCF_SDRAMC_DACR0, mbar_readLong(MCF_SDRAMC_DACR0)
				| MCF_SDRAMC_DACRn_MRS);
		asm(" nop");

		/*
		 * Write to the SDRAM Mode Register A0-A11 = 0x400
		 *
		 * Write Burst Mode = Programmed Burst Length
		 * Op Mode = Standard Op
		 * CAS Latency = 2
		 * Burst Type = Sequential
		 * Burst Length = 1
		 */
		*(u32 *)(CONFIG_SYS_SDRAM_BASE + 0x400) = 0xa5a5a5a5;
		asm(" nop");
	}

	return CONFIG_SYS_SDRAM_SIZE * 1024 * 1024;
};

int testdram (void) {

	/* TODO: XXX XXX XXX */
	printf ("DRAM test not implemented!\n");

	return (0);
}
OpenPOWER on IntegriCloud