arch/metag/kernel/devtree.c

   1 /*
   2  *  linux/arch/metag/kernel/devtree.c
   3  *
   4  *  Copyright (C) 2012 Imagination Technologies Ltd.
   5  *
   6  *  Based on ARM version:
   7  *  Copyright (C) 2009 Canonical Ltd. <jeremy.kerr@canonical.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/init.h>
  15 #include <linux/export.h>
  16 #include <linux/types.h>
  17 #include <linux/bootmem.h>
  18 #include <linux/memblock.h>
  19 #include <linux/of.h>
  20 #include <linux/of_fdt.h>
  21
  22 #include <asm/setup.h>
  23 #include <asm/page.h>
  24 #include <asm/mach/arch.h>
  25
  26 void __init early_init_dt_add_memory_arch(u64 base, u64 size)
  27 {
  28         pr_err("%s(%llx, %llx)\n",
  29                __func__, base, size);
  30 }
  31
  32 void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
  33 {
  34         return alloc_bootmem_align(size, align);
  35 }
  36
  37 /**
  38  * setup_machine_fdt - Machine setup when an dtb was passed to the kernel
  39  * @dt:         virtual address pointer to dt blob
  40  *
  41  * If a dtb was passed to the kernel, then use it to choose the correct
  42  * machine_desc and to setup the system.
  43  */
  44 struct machine_desc * __init setup_machine_fdt(void *dt)
  45 {
  46         struct boot_param_header *devtree = dt;
  47         struct machine_desc *mdesc, *mdesc_best = NULL;
  48         unsigned int score, mdesc_score = ~1;
  49         unsigned long dt_root;
  50         const char *model;
  51
  52         /* check device tree validity */
  53         if (be32_to_cpu(devtree->magic) != OF_DT_HEADER)
  54                 return NULL;
  55
  56         /* Search the mdescs for the 'best' compatible value match */
  57         initial_boot_params = devtree;
  58         dt_root = of_get_flat_dt_root();
  59
  60         for_each_machine_desc(mdesc) {
  61                 score = of_flat_dt_match(dt_root, mdesc->dt_compat);
  62                 if (score > 0 && score < mdesc_score) {
  63                         mdesc_best = mdesc;
  64                         mdesc_score = score;
  65                 }
  66         }
  67         if (!mdesc_best) {
  68                 const char *prop;
  69                 long size;
  70
  71                 pr_err("\nError: unrecognized/unsupported device tree compatible list:\n[ ");
  72
  73                 prop = of_get_flat_dt_prop(dt_root, "compatible", &size);
  74                 if (prop) {
  75                         while (size > 0) {
  76                                 printk("'%s' ", prop);
  77                                 size -= strlen(prop) + 1;
  78                                 prop += strlen(prop) + 1;
  79                         }
  80                 }
  81                 printk("]\n\n");
  82
  83                 dump_machine_table(); /* does not return */
  84         }
  85
  86         model = of_get_flat_dt_prop(dt_root, "model", NULL);
  87         if (!model)
  88                 model = of_get_flat_dt_prop(dt_root, "compatible", NULL);
  89         if (!model)
  90                 model = "<unknown>";
  91         pr_info("Machine: %s, model: %s\n", mdesc_best->name, model);
  92
  93         /* Retrieve various information from the /chosen node */
  94         of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
  95
  96         return mdesc_best;
  97 }
  98
  99 /**
 100  * copy_fdt - Copy device tree into non-init memory.
 101  *
 102  * We must copy the flattened device tree blob into non-init memory because the
 103  * unflattened device tree will reference the strings in it directly.
 104  */
 105 void __init copy_fdt(void)
 106 {
 107         void *alloc = early_init_dt_alloc_memory_arch(
 108                         be32_to_cpu(initial_boot_params->totalsize), 0x40);
 109         if (alloc) {
 110                 memcpy(alloc, initial_boot_params,
 111                        be32_to_cpu(initial_boot_params->totalsize));
 112                 initial_boot_params = alloc;
 113         }
 114 }