1 /* 2 * Copyright (C) 2006-2007 PA Semi, Inc 3 * 4 * Maintained by: Olof Johansson <olof@lixom.net> 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 2 as 8 * published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 18 * 19 */ 20 21 #undef DEBUG 22 23 #include <linux/kernel.h> 24 #include <linux/string.h> 25 26 #include <asm/machdep.h> 27 #include <asm/reg.h> 28 29 #include "pasemi.h" 30 31 struct sleep_mode { 32 char *name; 33 void (*entry)(void); 34 }; 35 36 static struct sleep_mode modes[] = { 37 { .name = "spin", .entry = &idle_spin }, 38 { .name = "doze", .entry = &idle_doze }, 39 }; 40 41 static int current_mode = 0; 42 43 static int pasemi_system_reset_exception(struct pt_regs *regs) 44 { 45 /* If we were woken up from power savings, we need to return 46 * to the calling function, since nip is not saved across 47 * all modes. 48 */ 49 50 if (regs->msr & SRR1_WAKEMASK) 51 regs->nip = regs->link; 52 53 switch (regs->msr & SRR1_WAKEMASK) { 54 case SRR1_WAKEEE: 55 do_IRQ(regs); 56 break; 57 case SRR1_WAKEDEC: 58 timer_interrupt(regs); 59 break; 60 default: 61 /* do system reset */ 62 return 0; 63 } 64 /* everything handled */ 65 regs->msr |= MSR_RI; 66 return 1; 67 } 68 69 void __init pasemi_idle_init(void) 70 { 71 ppc_md.system_reset_exception = pasemi_system_reset_exception; 72 ppc_md.power_save = modes[current_mode].entry; 73 printk(KERN_INFO "Using PA6T idle loop (%s)\n", modes[current_mode].name); 74 } 75 76 static int __init idle_param(char *p) 77 { 78 int i; 79 for (i = 0; i < sizeof(modes)/sizeof(struct sleep_mode); i++) { 80 if (!strcmp(modes[i].name, p)) { 81 current_mode = i; 82 break; 83 } 84 } 85 return 0; 86 } 87 88 early_param("idle", idle_param); 89