xref: /openbmc/u-boot/board/xes/xpedite520x/ddr.c (revision ad5b5801)
1 /*
2  * Copyright 2008 Freescale Semiconductor, Inc.
3  *
4  * SPDX-License-Identifier:	GPL-2.0
5  */
6 
7 #include <common.h>
8 #include <i2c.h>
9 
10 #include <fsl_ddr_sdram.h>
11 #include <fsl_ddr_dimm_params.h>
12 
13 void get_spd(ddr2_spd_eeprom_t *spd, unsigned char i2c_address)
14 {
15 	i2c_read(i2c_address, 0, 1, (uchar *)spd, sizeof(ddr2_spd_eeprom_t));
16 
17 	/* We use soldered memory, but use an SPD EEPROM to describe it.
18 	 * The SPD has an unspecified dimm type, but the DDR2 initialization
19 	 * code requires a specific type to be specified. This sets the type
20 	 * as a standard unregistered SO-DIMM. */
21 	if (spd->dimm_type == 0) {
22 		spd->dimm_type = 0x4;
23 		((uchar *)spd)[63] += 0x4;
24 	}
25 }
26 
27 void fsl_ddr_board_options(memctl_options_t *popts,
28 				dimm_params_t *pdimm,
29 				unsigned int ctrl_num)
30 {
31 	/*
32 	 * Factors to consider for clock adjust:
33 	 *	- number of chips on bus
34 	 *	- position of slot
35 	 *	- DDR1 vs. DDR2?
36 	 *	- ???
37 	 *
38 	 * This needs to be determined on a board-by-board basis.
39 	 *	0110	3/4 cycle late
40 	 *	0111	7/8 cycle late
41 	 */
42 	popts->clk_adjust = 7;
43 
44 	/*
45 	 * Factors to consider for CPO:
46 	 *	- frequency
47 	 *	- ddr1 vs. ddr2
48 	 */
49 	popts->cpo_override = 9;
50 
51 	/*
52 	 * Factors to consider for write data delay:
53 	 *	- number of DIMMs
54 	 *
55 	 * 1 = 1/4 clock delay
56 	 * 2 = 1/2 clock delay
57 	 * 3 = 3/4 clock delay
58 	 * 4 = 1   clock delay
59 	 * 5 = 5/4 clock delay
60 	 * 6 = 3/2 clock delay
61 	 */
62 	popts->write_data_delay = 3;
63 
64 	/*
65 	 * Factors to consider for half-strength driver enable:
66 	 *	- number of DIMMs installed
67 	 */
68 	popts->half_strength_driver_enable = 0;
69 }
70