xref: /openbmc/u-boot/board/gdsys/mpc8308/sdram.c (revision ae485b54)
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2007 Freescale Semiconductor, Inc.
4  * Copyright (C) 2010 Ilya Yanok, Emcraft Systems, yanok@emcraft.com
5  *
6  * Authors: Nick.Spence@freescale.com
7  *          Wilson.Lo@freescale.com
8  *          scottwood@freescale.com
9  *
10  * This files is  mostly identical to the original from
11  * board\freescale\mpc8315erdb\sdram.c
12  */
13 
14 #include <common.h>
15 #include <mpc83xx.h>
16 #include <spd_sdram.h>
17 
18 #include <asm/bitops.h>
19 #include <asm/io.h>
20 
21 #include <asm/processor.h>
22 
23 DECLARE_GLOBAL_DATA_PTR;
24 
25 /* Fixed sdram init -- doesn't use serial presence detect.
26  *
27  * This is useful for faster booting in configs where the RAM is unlikely
28  * to be changed, or for things like NAND booting where space is tight.
29  */
30 static long fixed_sdram(void)
31 {
32 	immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
33 	u32 msize = CONFIG_SYS_DDR_SIZE * 1024 * 1024;
34 	u32 msize_log2 = __ilog2(msize);
35 
36 	out_be32(&im->sysconf.ddrlaw[0].bar,
37 		 CONFIG_SYS_DDR_SDRAM_BASE  & 0xfffff000);
38 	out_be32(&im->sysconf.ddrlaw[0].ar, LBLAWAR_EN | (msize_log2 - 1));
39 	out_be32(&im->sysconf.ddrcdr, CONFIG_SYS_DDRCDR_VALUE);
40 
41 	out_be32(&im->ddr.csbnds[0].csbnds, (msize - 1) >> 24);
42 	out_be32(&im->ddr.cs_config[0], CONFIG_SYS_DDR_CS0_CONFIG);
43 
44 	/* Currently we use only one CS, so disable the other bank. */
45 	out_be32(&im->ddr.cs_config[1], 0);
46 
47 	out_be32(&im->ddr.sdram_clk_cntl, CONFIG_SYS_DDR_SDRAM_CLK_CNTL);
48 	out_be32(&im->ddr.timing_cfg_3, CONFIG_SYS_DDR_TIMING_3);
49 	out_be32(&im->ddr.timing_cfg_1, CONFIG_SYS_DDR_TIMING_1);
50 	out_be32(&im->ddr.timing_cfg_2, CONFIG_SYS_DDR_TIMING_2);
51 	out_be32(&im->ddr.timing_cfg_0, CONFIG_SYS_DDR_TIMING_0);
52 
53 	out_be32(&im->ddr.sdram_cfg, CONFIG_SYS_DDR_SDRAM_CFG);
54 	out_be32(&im->ddr.sdram_cfg2, CONFIG_SYS_DDR_SDRAM_CFG2);
55 	out_be32(&im->ddr.sdram_mode, CONFIG_SYS_DDR_MODE);
56 	out_be32(&im->ddr.sdram_mode2, CONFIG_SYS_DDR_MODE2);
57 
58 	out_be32(&im->ddr.sdram_interval, CONFIG_SYS_DDR_INTERVAL);
59 	sync();
60 
61 	/* enable DDR controller */
62 	setbits_be32(&im->ddr.sdram_cfg, SDRAM_CFG_MEM_EN);
63 	sync();
64 
65 	return get_ram_size(CONFIG_SYS_DDR_SDRAM_BASE, msize);
66 }
67 
68 int dram_init(void)
69 {
70 	immap_t *im = (immap_t *)CONFIG_SYS_IMMR;
71 	u32 msize;
72 
73 	if ((in_be32(&im->sysconf.immrbar) & IMMRBAR_BASE_ADDR) != (u32)im)
74 		return -ENXIO;
75 
76 	/* DDR SDRAM */
77 	msize = fixed_sdram();
78 
79 	/* return total bus SDRAM size(bytes)  -- DDR */
80 	gd->ram_size = msize;
81 
82 	return 0;
83 }
84