LXR linux/arch/powerpc/kernel/epapr

   1/*
   2 * ePAPR para-virtualization support.
   3 *
   4 * This program is free software; you can redistribute it and/or modify
   5 * it under the terms of the GNU General Public License, version 2, as
   6 * published by the Free Software Foundation.
   7 *
   8 * This program is distributed in the hope that it will be useful,
   9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11 * GNU General Public License for more details.
  12 *
  13 * You should have received a copy of the GNU General Public License
  14 * along with this program; if not, write to the Free Software
  15 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  16 *
  17 * Copyright (C) 2012 Freescale Semiconductor, Inc.
  18 */
  19
  20#include <linux/of.h>
  21#include <asm/epapr_hcalls.h>
  22#include <asm/cacheflush.h>
  23#include <asm/code-patching.h>
  24
  25bool epapr_paravirt_enabled;
  26
  27static int __init epapr_paravirt_init(void)
  28{
  29        struct device_node *hyper_node;
  30        const u32 *insts;
  31        int len, i;
  32
  33        hyper_node = of_find_node_by_path("/hypervisor");
  34        if (!hyper_node)
  35                return -ENODEV;
  36
  37        insts = of_get_property(hyper_node, "hcall-instructions", &len);
  38        if (!insts)
  39                return -ENODEV;
  40
  41        if (len % 4 || len > (4 * 4))
  42                return -ENODEV;
  43
  44        for (i = 0; i < (len / 4); i++)
  45                patch_instruction(epapr_hypercall_start + i, insts[i]);
  46
  47        epapr_paravirt_enabled = true;
  48
  49        return 0;
  50}
  51
  52early_initcall(epapr_paravirt_init);
  53