arch/arm/plat-omap/sram.c

   1 /*
   2  * linux/arch/arm/plat-omap/sram.c
   3  *
   4  * OMAP SRAM detection and management
   5  *
   6  * Copyright (C) 2005 Nokia Corporation
   7  * Written by Tony Lindgren <tony@atomide.com>
   8  *
   9  * This program is free software; you can redistribute it and/or modify
  10  * it under the terms of the GNU General Public License version 2 as
  11  * published by the Free Software Foundation.
  12  */
  13
  14 #include <linux/config.h>
  15 #include <linux/module.h>
  16 #include <linux/kernel.h>
  17 #include <linux/init.h>
  18
  19 #include <asm/mach/map.h>
  20 #include <asm/tlb.h>
  21 #include <asm/io.h>
  22 #include <asm/cacheflush.h>
  23
  24 #include <asm/arch/sram.h>
  25
  26 #define OMAP1_SRAM_PA           0x20000000
  27 #define OMAP1_SRAM_VA           0xd0000000
  28 #define OMAP2_SRAM_PA           0x40200000
  29 #define OMAP2_SRAM_VA           0xd0000000
  30
  31 #define SRAM_BOOTLOADER_SZ      0x80
  32
  33 static unsigned long omap_sram_base;
  34 static unsigned long omap_sram_size;
  35 static unsigned long omap_sram_ceil;
  36
  37 /*
  38  * The amount of SRAM depends on the core type.
  39  * Note that we cannot try to test for SRAM here because writes
  40  * to secure SRAM will hang the system. Also the SRAM is not
  41  * yet mapped at this point.
  42  */
  43 void __init omap_detect_sram(void)
  44 {
  45         if (!cpu_is_omap24xx())
  46                 omap_sram_base = OMAP1_SRAM_VA;
  47         else
  48                 omap_sram_base = OMAP2_SRAM_VA;
  49
  50         if (cpu_is_omap730())
  51                 omap_sram_size = 0x32000;       /* 200K */
  52         else if (cpu_is_omap15xx())
  53                 omap_sram_size = 0x30000;       /* 192K */
  54         else if (cpu_is_omap1610() || cpu_is_omap1621() || cpu_is_omap1710())
  55                 omap_sram_size = 0x4000;        /* 16K */
  56         else if (cpu_is_omap1611())
  57                 omap_sram_size = 0x3e800;       /* 250K */
  58         else if (cpu_is_omap2420())
  59                 omap_sram_size = 0xa0014;       /* 640K */
  60         else {
  61                 printk(KERN_ERR "Could not detect SRAM size\n");
  62                 omap_sram_size = 0x4000;
  63         }
  64
  65         omap_sram_ceil = omap_sram_base + omap_sram_size;
  66 }
  67
  68 static struct map_desc omap_sram_io_desc[] __initdata = {
  69         {       /* .length gets filled in at runtime */
  70                 .virtual        = OMAP1_SRAM_VA,
  71                 .pfn            = __phys_to_pfn(OMAP1_SRAM_PA),
  72                 .type           = MT_DEVICE
  73         }
  74 };
  75
  76 /*
  77  * In order to use last 2kB of SRAM on 1611b, we must round the size
  78  * up to multiple of PAGE_SIZE. We cannot use ioremap for SRAM, as
  79  * clock init needs SRAM early.
  80  */
  81 void __init omap_map_sram(void)
  82 {
  83         if (omap_sram_size == 0)
  84                 return;
  85
  86         if (cpu_is_omap24xx()) {
  87                 omap_sram_io_desc[0].virtual = OMAP2_SRAM_VA;
  88                 omap_sram_io_desc[0].pfn = __phys_to_pfn(OMAP2_SRAM_PA);
  89         }
  90
  91         omap_sram_io_desc[0].length = (omap_sram_size + PAGE_SIZE-1)/PAGE_SIZE;
  92         omap_sram_io_desc[0].length *= PAGE_SIZE;
  93         iotable_init(omap_sram_io_desc, ARRAY_SIZE(omap_sram_io_desc));
  94
  95         printk(KERN_INFO "SRAM: Mapped pa 0x%08lx to va 0x%08lx size: 0x%lx\n",
  96                omap_sram_io_desc[0].pfn, omap_sram_io_desc[0].virtual,
  97                omap_sram_io_desc[0].length);
  98
  99         /*
 100          * Normally devicemaps_init() would flush caches and tlb after
 101          * mdesc->map_io(), but since we're called from map_io(), we
 102          * must do it here.
 103          */
 104         local_flush_tlb_all();
 105         flush_cache_all();
 106
 107         /*
 108          * Looks like we need to preserve some bootloader code at the
 109          * beginning of SRAM for jumping to flash for reboot to work...
 110          */
 111         memset((void *)omap_sram_base + SRAM_BOOTLOADER_SZ, 0,
 112                omap_sram_size - SRAM_BOOTLOADER_SZ);
 113 }
 114
 115 void * omap_sram_push(void * start, unsigned long size)
 116 {
 117         if (size > (omap_sram_ceil - (omap_sram_base + SRAM_BOOTLOADER_SZ))) {
 118                 printk(KERN_ERR "Not enough space in SRAM\n");
 119                 return NULL;
 120         }
 121         omap_sram_ceil -= size;
 122         omap_sram_ceil &= ~0x3;
 123         memcpy((void *)omap_sram_ceil, start, size);
 124
 125         return (void *)omap_sram_ceil;
 126 }
 127
 128 static void omap_sram_error(void)
 129 {
 130         panic("Uninitialized SRAM function\n");
 131 }
 132
 133 #ifdef CONFIG_ARCH_OMAP1
 134
 135 static void (*_omap_sram_reprogram_clock)(u32 dpllctl, u32 ckctl);
 136
 137 void omap_sram_reprogram_clock(u32 dpllctl, u32 ckctl)
 138 {
 139         if (!_omap_sram_reprogram_clock)
 140                 omap_sram_error();
 141
 142         return _omap_sram_reprogram_clock(dpllctl, ckctl);
 143 }
 144
 145 int __init omap1_sram_init(void)
 146 {
 147         _omap_sram_reprogram_clock = omap_sram_push(sram_reprogram_clock,
 148                                                     sram_reprogram_clock_sz);
 149
 150         return 0;
 151 }
 152
 153 #else
 154 #define omap1_sram_init()       do {} while (0)
 155 #endif
 156
 157 #ifdef CONFIG_ARCH_OMAP2
 158
 159 static void (*_omap2_sram_ddr_init)(u32 *slow_dll_ctrl, u32 fast_dll_ctrl,
 160                               u32 base_cs, u32 force_unlock);
 161
 162 void omap2_sram_ddr_init(u32 *slow_dll_ctrl, u32 fast_dll_ctrl,
 163                    u32 base_cs, u32 force_unlock)
 164 {
 165         if (!_omap2_sram_ddr_init)
 166                 omap_sram_error();
 167
 168         return _omap2_sram_ddr_init(slow_dll_ctrl, fast_dll_ctrl,
 169                                     base_cs, force_unlock);
 170 }
 171
 172 static void (*_omap2_sram_reprogram_sdrc)(u32 perf_level, u32 dll_val,
 173                                           u32 mem_type);
 174
 175 void omap2_sram_reprogram_sdrc(u32 perf_level, u32 dll_val, u32 mem_type)
 176 {
 177         if (!_omap2_sram_reprogram_sdrc)
 178                 omap_sram_error();
 179
 180         return _omap2_sram_reprogram_sdrc(perf_level, dll_val, mem_type);
 181 }
 182
 183 static u32 (*_omap2_set_prcm)(u32 dpll_ctrl_val, u32 sdrc_rfr_val, int bypass);
 184
 185 u32 omap2_set_prcm(u32 dpll_ctrl_val, u32 sdrc_rfr_val, int bypass)
 186 {
 187         if (!_omap2_set_prcm)
 188                 omap_sram_error();
 189
 190         return _omap2_set_prcm(dpll_ctrl_val, sdrc_rfr_val, bypass);
 191 }
 192
 193 int __init omap2_sram_init(void)
 194 {
 195         _omap2_sram_ddr_init = omap_sram_push(sram_ddr_init, sram_ddr_init_sz);
 196
 197         _omap2_sram_reprogram_sdrc = omap_sram_push(sram_reprogram_sdrc,
 198                                                     sram_reprogram_sdrc_sz);
 199         _omap2_set_prcm = omap_sram_push(sram_set_prcm, sram_set_prcm_sz);
 200
 201         return 0;
 202 }
 203 #else
 204 #define omap2_sram_init()       do {} while (0)
 205 #endif
 206
 207 int __init omap_sram_init(void)
 208 {
 209         omap_detect_sram();
 210         omap_map_sram();
 211
 212         if (!cpu_is_omap24xx())
 213                 omap1_sram_init();
 214         else
 215                 omap2_sram_init();
 216
 217         return 0;
 218 }