xref: /openbmc/u-boot/board/sbc8548/ddr.c (revision bf48fcb6)
1 /*
2  * Copyright 2008 Freescale Semiconductor, Inc.
3  *
4  * This program is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU General Public License
6  * Version 2 as published by the Free Software Foundation.
7  */
8 
9 #include <common.h>
10 #include <i2c.h>
11 
12 #include <asm/fsl_ddr_sdram.h>
13 #include <asm/fsl_ddr_dimm_params.h>
14 
15 void fsl_ddr_board_options(memctl_options_t *popts,
16 				dimm_params_t *pdimm,
17 				unsigned int ctrl_num)
18 {
19 	/*
20 	 * Factors to consider for clock adjust:
21 	 *	- number of chips on bus
22 	 *	- position of slot
23 	 *	- DDR1 vs. DDR2?
24 	 *	- ???
25 	 *
26 	 * This needs to be determined on a board-by-board basis.
27 	 *	0110	3/4 cycle late
28 	 *	0111	7/8 cycle late
29 	 */
30 	popts->clk_adjust = 7;
31 
32 	/*
33 	 * Factors to consider for CPO:
34 	 *	- frequency
35 	 *	- ddr1 vs. ddr2
36 	 */
37 	popts->cpo_override = 10;
38 
39 	/*
40 	 * Factors to consider for write data delay:
41 	 *	- number of DIMMs
42 	 *
43 	 * 1 = 1/4 clock delay
44 	 * 2 = 1/2 clock delay
45 	 * 3 = 3/4 clock delay
46 	 * 4 = 1   clock delay
47 	 * 5 = 5/4 clock delay
48 	 * 6 = 3/2 clock delay
49 	 */
50 	popts->write_data_delay = 3;
51 
52 	/*
53 	 * Factors to consider for half-strength driver enable:
54 	 *	- number of DIMMs installed
55 	 */
56 	popts->half_strength_driver_enable = 0;
57 }
58 
59 #ifdef CONFIG_SPD_EEPROM
60 /*
61  * Workaround for hardware errata.  An i2c address conflict
62  * existed on earlier boards; the workaround moved the DDR
63  * SPD from 0x51 to 0x53.  So we try and read 0x53 1st, and
64  * if that fails, then fall back to reading at 0x51.
65  */
66 void get_spd(generic_spd_eeprom_t *spd, u8 i2c_address)
67 {
68 	int ret;
69 
70 #ifdef ALT_SPD_EEPROM_ADDRESS
71 	if (i2c_address == SPD_EEPROM_ADDRESS) {
72 		ret = i2c_read(ALT_SPD_EEPROM_ADDRESS, 0, 1, (uchar *)spd,
73 				sizeof(generic_spd_eeprom_t));
74 		if (ret == 0)
75 			return;		/* Good data at 0x53 */
76 		memset(spd, 0, sizeof(generic_spd_eeprom_t));
77 	}
78 #endif
79 	ret = i2c_read(i2c_address, 0, 1, (uchar *)spd,
80 				sizeof(generic_spd_eeprom_t));
81 	if (ret) {
82 		printf("DDR: failed to read SPD from addr %u\n", i2c_address);
83 		memset(spd, 0, sizeof(generic_spd_eeprom_t));
84 	}
85 }
86 
87 #else
88 /*
89  *  fixed_sdram init -- doesn't use serial presence detect.
90  *  Assumes 256MB DDR2 SDRAM SODIMM, without ECC, running at DDR400 speed.
91  */
92 phys_size_t fixed_sdram(void)
93 {
94 	volatile ccsr_ddr_t *ddr = (void *)(CONFIG_SYS_MPC8xxx_DDR_ADDR);
95 
96 	out_be32(&ddr->cs0_bnds,	0x0000007f);
97 	out_be32(&ddr->cs1_bnds,	0x008000ff);
98 	out_be32(&ddr->cs2_bnds,	0x00000000);
99 	out_be32(&ddr->cs3_bnds,	0x00000000);
100 
101 	out_be32(&ddr->cs0_config,	0x80010101);
102 	out_be32(&ddr->cs1_config,	0x80010101);
103 	out_be32(&ddr->cs2_config,	0x00000000);
104 	out_be32(&ddr->cs3_config,	0x00000000);
105 
106 	out_be32(&ddr->timing_cfg_3,	0x00000000);
107 	out_be32(&ddr->timing_cfg_0,	0x00220802);
108 	out_be32(&ddr->timing_cfg_1,	0x38377322);
109 	out_be32(&ddr->timing_cfg_2,	0x0fa044C7);
110 
111 	out_be32(&ddr->sdram_cfg,	0x4300C000);
112 	out_be32(&ddr->sdram_cfg_2,	0x24401000);
113 
114 	out_be32(&ddr->sdram_mode,	0x23C00542);
115 	out_be32(&ddr->sdram_mode_2,	0x00000000);
116 
117 	out_be32(&ddr->sdram_interval,	0x05080100);
118 	out_be32(&ddr->sdram_md_cntl,	0x00000000);
119 	out_be32(&ddr->sdram_data_init,	0x00000000);
120 	out_be32(&ddr->sdram_clk_cntl,	0x03800000);
121 	asm("sync;isync;msync");
122 	udelay(500);
123 
124 	#ifdef CONFIG_DDR_ECC
125 	  /* Enable ECC checking */
126 	  out_be32(&ddr->sdram_cfg, CONFIG_SYS_DDR_CONTROL | 0x20000000);
127 	#else
128 	  out_be32(&ddr->sdram_cfg, CONFIG_SYS_DDR_CONTROL);
129 	#endif
130 
131 	return CONFIG_SYS_SDRAM_SIZE * 1024 * 1024;
132 }
133 #endif
134