board/freescale/mpc8315erdb/sdram.c

   1 /*
   2  * Copyright (C) 2007 Freescale Semiconductor, Inc.
   3  *
   4  * Authors: Nick.Spence@freescale.com
   5  *          Wilson.Lo@freescale.com
   6  *          scottwood@freescale.com
   7  *
   8  * SPDX-License-Identifier:     GPL-2.0+
   9  */
  10
  11 #include <common.h>
  12 #include <mpc83xx.h>
  13 #include <spd_sdram.h>
  14
  15 #include <asm/bitops.h>
  16 #include <asm/io.h>
  17
  18 #include <asm/processor.h>
  19
  20 DECLARE_GLOBAL_DATA_PTR;
  21
  22 static void resume_from_sleep(void)
  23 {
  24         u32 magic = *(u32 *)0;
  25
  26         typedef void (*func_t)(void);
  27         func_t resume = *(func_t *)4;
  28
  29         if (magic == 0xf5153ae5)
  30                 resume();
  31
  32         gd->flags &= ~GD_FLG_SILENT;
  33         puts("\nResume from sleep failed: bad magic word\n");
  34 }
  35
  36 /* Fixed sdram init -- doesn't use serial presence detect.
  37  *
  38  * This is useful for faster booting in configs where the RAM is unlikely
  39  * to be changed, or for things like NAND booting where space is tight.
  40  */
  41 #ifndef CONFIG_SYS_RAMBOOT
  42 static long fixed_sdram(void)
  43 {
  44         volatile immap_t *im = (volatile immap_t *)CONFIG_SYS_IMMR;
  45         u32 msize = CONFIG_SYS_DDR_SIZE * 1024 * 1024;
  46         u32 msize_log2 = __ilog2(msize);
  47
  48         im->sysconf.ddrlaw[0].bar = CONFIG_SYS_DDR_SDRAM_BASE  & 0xfffff000;
  49         im->sysconf.ddrlaw[0].ar = LBLAWAR_EN | (msize_log2 - 1);
  50         im->sysconf.ddrcdr = CONFIG_SYS_DDRCDR_VALUE;
  51
  52         /*
  53          * Erratum DDR3 requires a 50ms delay after clearing DDRCDR[DDR_cfg],
  54          * or the DDR2 controller may fail to initialize correctly.
  55          */
  56         __udelay(50000);
  57
  58         im->ddr.csbnds[0].csbnds = (msize - 1) >> 24;
  59         im->ddr.cs_config[0] = CONFIG_SYS_DDR_CS0_CONFIG;
  60
  61         /* Currently we use only one CS, so disable the other bank. */
  62         im->ddr.cs_config[1] = 0;
  63
  64         im->ddr.sdram_clk_cntl = CONFIG_SYS_DDR_SDRAM_CLK_CNTL;
  65         im->ddr.timing_cfg_3 = CONFIG_SYS_DDR_TIMING_3;
  66         im->ddr.timing_cfg_1 = CONFIG_SYS_DDR_TIMING_1;
  67         im->ddr.timing_cfg_2 = CONFIG_SYS_DDR_TIMING_2;
  68         im->ddr.timing_cfg_0 = CONFIG_SYS_DDR_TIMING_0;
  69
  70         if (im->pmc.pmccr1 & PMCCR1_POWER_OFF)
  71                 im->ddr.sdram_cfg = CONFIG_SYS_DDR_SDRAM_CFG | SDRAM_CFG_BI;
  72         else
  73                 im->ddr.sdram_cfg = CONFIG_SYS_DDR_SDRAM_CFG;
  74
  75         im->ddr.sdram_cfg2 = CONFIG_SYS_DDR_SDRAM_CFG2;
  76         im->ddr.sdram_mode = CONFIG_SYS_DDR_MODE;
  77         im->ddr.sdram_mode2 = CONFIG_SYS_DDR_MODE2;
  78
  79         im->ddr.sdram_interval = CONFIG_SYS_DDR_INTERVAL;
  80         sync();
  81
  82         /* enable DDR controller */
  83         im->ddr.sdram_cfg |= SDRAM_CFG_MEM_EN;
  84         sync();
  85
  86         return msize;
  87 }
  88 #else
  89 static long fixed_sdram(void)
  90 {
  91         return CONFIG_SYS_DDR_SIZE * 1024 * 1024;
  92 }
  93 #endif /* CONFIG_SYS_RAMBOOT */
  94
  95 int initdram(void)
  96 {
  97         volatile immap_t *im = (volatile immap_t *)CONFIG_SYS_IMMR;
  98         u32 msize;
  99
 100         if ((im->sysconf.immrbar & IMMRBAR_BASE_ADDR) != (u32)im)
 101                 return -ENXIO;
 102
 103         /* DDR SDRAM */
 104         msize = fixed_sdram();
 105
 106         if (im->pmc.pmccr1 & PMCCR1_POWER_OFF)
 107                 resume_from_sleep();
 108
 109         /* set total bus SDRAM size(bytes)  -- DDR */
 110         gd->ram_size = msize;
 111
 112         return 0;
 113 }