arch/arm/mach-omap1/sram-init.c

   1 /*
   2  * OMAP SRAM detection and management
   3  *
   4  * Copyright (C) 2005 Nokia Corporation
   5  * Written by Tony Lindgren <tony@atomide.com>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License version 2 as
   9  * published by the Free Software Foundation.
  10  */
  11
  12 #include <linux/module.h>
  13 #include <linux/kernel.h>
  14 #include <linux/init.h>
  15 #include <linux/io.h>
  16
  17 #include <asm/fncpy.h>
  18 #include <asm/tlb.h>
  19 #include <asm/cacheflush.h>
  20
  21 #include <asm/mach/map.h>
  22
  23 #include "soc.h"
  24 #include "sram.h"
  25
  26 #define OMAP1_SRAM_PA           0x20000000
  27 #define SRAM_BOOTLOADER_SZ      0x80
  28
  29 /*
  30  * The amount of SRAM depends on the core type.
  31  * Note that we cannot try to test for SRAM here because writes
  32  * to secure SRAM will hang the system. Also the SRAM is not
  33  * yet mapped at this point.
  34  */
  35 static void __init omap_detect_and_map_sram(void)
  36 {
  37         unsigned long omap_sram_skip = SRAM_BOOTLOADER_SZ;
  38         unsigned long omap_sram_start = OMAP1_SRAM_PA;
  39         unsigned long omap_sram_size;
  40
  41         if (cpu_is_omap7xx())
  42                 omap_sram_size = 0x32000;       /* 200K */
  43         else if (cpu_is_omap15xx())
  44                 omap_sram_size = 0x30000;       /* 192K */
  45         else if (cpu_is_omap1610() || cpu_is_omap1611() ||
  46                         cpu_is_omap1621() || cpu_is_omap1710())
  47                 omap_sram_size = 0x4000;        /* 16K */
  48         else {
  49                 pr_err("Could not detect SRAM size\n");
  50                 omap_sram_size = 0x4000;
  51         }
  52
  53         omap_map_sram(omap_sram_start, omap_sram_size,
  54                 omap_sram_skip, 1);
  55 }
  56
  57 static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl);
  58
  59 void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
  60 {
  61         BUG_ON(!_omap_sram_reprogram_clock);
  62         /* On 730, bit 13 must always be 1 */
  63         if (cpu_is_omap7xx())
  64                 ckctl |= 0x2000;
  65         _omap_sram_reprogram_clock(dpllctl, ckctl);
  66 }
  67
  68 int __init omap_sram_init(void)
  69 {
  70         omap_detect_and_map_sram();
  71         _omap_sram_reprogram_clock =
  72                         omap_sram_push(omap1_sram_reprogram_clock,
  73                                         omap1_sram_reprogram_clock_sz);
  74
  75         return 0;
  76 }