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 #include <asm/machdep.h> 25 26 extern void epapr_ev_idle(void); 27 extern u32 epapr_ev_idle_start[]; 28 29 bool epapr_paravirt_enabled; 30 31 static int __init epapr_paravirt_init(void) 32 { 33 struct device_node *hyper_node; 34 const u32 *insts; 35 int len, i; 36 37 hyper_node = of_find_node_by_path("/hypervisor"); 38 if (!hyper_node) 39 return -ENODEV; 40 41 insts = of_get_property(hyper_node, "hcall-instructions", &len); 42 if (!insts) 43 return -ENODEV; 44 45 if (len % 4 || len > (4 * 4)) 46 return -ENODEV; 47 48 for (i = 0; i < (len / 4); i++) { 49 patch_instruction(epapr_hypercall_start + i, insts[i]); 50 patch_instruction(epapr_ev_idle_start + i, insts[i]); 51 } 52 53 if (of_get_property(hyper_node, "has-idle", NULL)) 54 ppc_md.power_save = epapr_ev_idle; 55 56 epapr_paravirt_enabled = true; 57 58 return 0; 59 } 60 61 early_initcall(epapr_paravirt_init); 62