arch/arm/mach-keystone/keystone.c

   1 /*
   2  * Keystone2 based boards and SOC related code.
   3  *
   4  * Copyright 2013 Texas Instruments, Inc.
   5  *      Cyril Chemparathy <cyril@ti.com>
   6  *      Santosh Shilimkar <santosh.shillimkar@ti.com>
   7  *
   8  * This program is free software; you can redistribute it and/or modify it
   9  * under the terms and conditions of the GNU General Public License,
  10  * version 2, as published by the Free Software Foundation.
  11  */
  12 #include <linux/io.h>
  13 #include <linux/of.h>
  14 #include <linux/init.h>
  15 #include <linux/of_platform.h>
  16 #include <linux/of_address.h>
  17 #include <linux/memblock.h>
  18
  19 #include <asm/setup.h>
  20 #include <asm/mach/map.h>
  21 #include <asm/mach/arch.h>
  22 #include <asm/mach/time.h>
  23 #include <asm/smp_plat.h>
  24 #include <asm/memory.h>
  25
  26 #include "memory.h"
  27
  28 #include "keystone.h"
  29
  30 static unsigned long keystone_dma_pfn_offset __read_mostly;
  31
  32 static int keystone_platform_notifier(struct notifier_block *nb,
  33                                       unsigned long event, void *data)
  34 {
  35         struct device *dev = data;
  36
  37         if (event != BUS_NOTIFY_ADD_DEVICE)
  38                 return NOTIFY_DONE;
  39
  40         if (!dev)
  41                 return NOTIFY_BAD;
  42
  43         if (!dev->of_node) {
  44                 dev->dma_pfn_offset = keystone_dma_pfn_offset;
  45                 dev_err(dev, "set dma_pfn_offset%08lx\n",
  46                         dev->dma_pfn_offset);
  47         }
  48         return NOTIFY_OK;
  49 }
  50
  51 static struct notifier_block platform_nb = {
  52         .notifier_call = keystone_platform_notifier,
  53 };
  54
  55 static void __init keystone_init(void)
  56 {
  57         if (PHYS_OFFSET >= KEYSTONE_HIGH_PHYS_START) {
  58                 keystone_dma_pfn_offset = PFN_DOWN(KEYSTONE_HIGH_PHYS_START -
  59                                                    KEYSTONE_LOW_PHYS_START);
  60                 bus_register_notifier(&platform_bus_type, &platform_nb);
  61         }
  62         keystone_pm_runtime_init();
  63 }
  64
  65 static long long __init keystone_pv_fixup(void)
  66 {
  67         long long offset;
  68         u64 mem_start, mem_end;
  69
  70         mem_start = memblock_start_of_DRAM();
  71         mem_end = memblock_end_of_DRAM();
  72
  73         /* nothing to do if we are running out of the <32-bit space */
  74         if (mem_start >= KEYSTONE_LOW_PHYS_START &&
  75             mem_end   <= KEYSTONE_LOW_PHYS_END)
  76                 return 0;
  77
  78         if (mem_start < KEYSTONE_HIGH_PHYS_START ||
  79             mem_end   > KEYSTONE_HIGH_PHYS_END) {
  80                 pr_crit("Invalid address space for memory (%08llx-%08llx)\n",
  81                         mem_start, mem_end);
  82                 return 0;
  83         }
  84
  85         offset = KEYSTONE_HIGH_PHYS_START - KEYSTONE_LOW_PHYS_START;
  86
  87         /* Populate the arch idmap hook */
  88         arch_phys_to_idmap_offset = -offset;
  89
  90         return offset;
  91 }
  92
  93 static const char *const keystone_match[] __initconst = {
  94         "ti,k2hk",
  95         "ti,k2e",
  96         "ti,k2l",
  97         "ti,k2g",
  98         "ti,keystone",
  99         NULL,
 100 };
 101
 102 DT_MACHINE_START(KEYSTONE, "Keystone")
 103 #if defined(CONFIG_ZONE_DMA) && defined(CONFIG_ARM_LPAE)
 104         .dma_zone_size  = SZ_2G,
 105 #endif
 106         .smp            = smp_ops(keystone_smp_ops),
 107         .init_machine   = keystone_init,
 108         .dt_compat      = keystone_match,
 109         .pv_fixup       = keystone_pv_fixup,
 110 MACHINE_END