1/* 2 * Copyright 2010 IBM Corp, Benjamin Herrenschmidt <benh@kernel.crashing.org> 3 * 4 * Generic idle routine for Book3E processors 5 * 6 * This program is free software; you can redistribute it and/or 7 * modify it under the terms of the GNU General Public License 8 * as published by the Free Software Foundation; either version 9 * 2 of the License, or (at your option) any later version. 10 */ 11 12#include <linux/threads.h> 13#include <asm/reg.h> 14#include <asm/ppc_asm.h> 15#include <asm/asm-offsets.h> 16#include <asm/ppc-opcode.h> 17#include <asm/processor.h> 18#include <asm/thread_info.h> 19 20/* 64-bit version only for now */ 21#ifdef CONFIG_PPC64 22 23_GLOBAL(book3e_idle) 24 /* Save LR for later */ 25 mflr r0 26 std r0,16(r1) 27 28 /* Hard disable interrupts */ 29 wrteei 0 30 31 /* Now check if an interrupt came in while we were soft disabled 32 * since we may otherwise lose it (doorbells etc...). We know 33 * that since PACAHARDIRQEN will have been cleared in that case. 34 */ 35 lbz r3,PACAHARDIRQEN(r13) 36 cmpwi cr0,r3,0 37 beqlr 38 39 /* Now we are going to mark ourselves as soft and hard enables in 40 * order to be able to take interrupts while asleep. We inform lockdep 41 * of that. We don't actually turn interrupts on just yet tho. 42 */ 43#ifdef CONFIG_TRACE_IRQFLAGS 44 stdu r1,-128(r1) 45 bl .trace_hardirqs_on 46#endif 47 li r0,1 48 stb r0,PACASOFTIRQEN(r13) 49 stb r0,PACAHARDIRQEN(r13) 50 51 /* Interrupts will make use return to LR, so get something we want 52 * in there 53 */ 54 bl 1f 55 56 /* Hard disable interrupts again */ 57 wrteei 0 58 59 /* Mark them off again in the PACA as well */ 60 li r0,0 61 stb r0,PACASOFTIRQEN(r13) 62 stb r0,PACAHARDIRQEN(r13) 63 64 /* Tell lockdep about it */ 65#ifdef CONFIG_TRACE_IRQFLAGS 66 bl .trace_hardirqs_off 67 addi r1,r1,128 68#endif 69 ld r0,16(r1) 70 mtlr r0 71 blr 72 731: /* Let's set the _TLF_NAPPING flag so interrupts make us return 74 * to the right spot 75 */ 76 clrrdi r11,r1,THREAD_SHIFT 77 ld r10,TI_LOCAL_FLAGS(r11) 78 ori r10,r10,_TLF_NAPPING 79 std r10,TI_LOCAL_FLAGS(r11) 80 81 /* We can now re-enable hard interrupts and go to sleep */ 82 wrteei 1 831: PPC_WAIT(0) 84 b 1b 85 86#endif /* CONFIG_PPC64 */ 87