LXR linux/arch/nios2/kernel/prom.c

   1/*
   2 * Device tree support
   3 *
   4 * Copyright (C) 2013, 2015 Altera Corporation
   5 * Copyright (C) 2010 Thomas Chou <thomas@wytron.com.tw>
   6 *
   7 * Based on MIPS support for CONFIG_OF device tree support
   8 *
   9 * Copyright (C) 2010 Cisco Systems Inc. <dediao@cisco.com>
  10 *
  11 * This program is free software; you can redistribute it and/or modify
  12 * it under the terms of the GNU General Public License as published by
  13 * the Free Software Foundation; either version 2 of the License, or
  14 * (at your option) any later version.
  15 *
  16 * This program is distributed in the hope that it will be useful,
  17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 * GNU General Public License for more details.
  20 *
  21 * You should have received a copy of the GNU General Public License
  22 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  23 *
  24 */
  25
  26#include <linux/init.h>
  27#include <linux/types.h>
  28#include <linux/bootmem.h>
  29#include <linux/of.h>
  30#include <linux/of_fdt.h>
  31#include <linux/io.h>
  32
  33#include <asm/prom.h>
  34#include <asm/sections.h>
  35
  36void __init early_init_dt_add_memory_arch(u64 base, u64 size)
  37{
  38        u64 kernel_start = (u64)virt_to_phys(_text);
  39
  40        if (!memory_size &&
  41            (kernel_start >= base) && (kernel_start < (base + size)))
  42                memory_size = size;
  43
  44}
  45
  46void * __init early_init_dt_alloc_memory_arch(u64 size, u64 align)
  47{
  48        return alloc_bootmem_align(size, align);
  49}
  50
  51void __init early_init_devtree(void *params)
  52{
  53        __be32 *dtb = (u32 *)__dtb_start;
  54#if defined(CONFIG_NIOS2_DTB_AT_PHYS_ADDR)
  55        if (be32_to_cpup((__be32 *)CONFIG_NIOS2_DTB_PHYS_ADDR) ==
  56                 OF_DT_HEADER) {
  57                params = (void *)CONFIG_NIOS2_DTB_PHYS_ADDR;
  58                early_init_dt_scan(params);
  59                return;
  60        }
  61#endif
  62        if (be32_to_cpu((__be32) *dtb) == OF_DT_HEADER)
  63                params = (void *)__dtb_start;
  64
  65        early_init_dt_scan(params);
  66}
  67
  68#ifdef CONFIG_EARLY_PRINTK
  69static int __init early_init_dt_scan_serial(unsigned long node,
  70                        const char *uname, int depth, void *data)
  71{
  72        u64 *addr64 = (u64 *) data;
  73        const char *p;
  74
  75        /* only consider serial nodes */
  76        if (strncmp(uname, "serial", 6) != 0)
  77                return 0;
  78
  79        p = of_get_flat_dt_prop(node, "compatible", NULL);
  80        if (!p)
  81                return 0;
  82
  83        /*
  84         * We found an altera_jtaguart but it wasn't configured for console, so
  85         * skip it.
  86         */
  87#ifndef CONFIG_SERIAL_ALTERA_JTAGUART_CONSOLE
  88        if (strncmp(p, "altr,juart", 10) == 0)
  89                return 0;
  90#endif
  91
  92        /*
  93         * Same for altera_uart.
  94         */
  95#ifndef CONFIG_SERIAL_ALTERA_UART_CONSOLE
  96        if (strncmp(p, "altr,uart", 9) == 0)
  97                return 0;
  98#endif
  99
 100        *addr64 = of_flat_dt_translate_address(node);
 101
 102        return *addr64 == OF_BAD_ADDR ? 0 : 1;
 103}
 104
 105unsigned long __init of_early_console(void)
 106{
 107        u64 base = 0;
 108
 109        if (of_scan_flat_dt(early_init_dt_scan_serial, &base))
 110                return (u32)ioremap(base, 32);
 111        else
 112                return 0;
 113}
 114#endif /* CONFIG_EARLY_PRINTK */
 115