| Benjamin Herrenschmidt | 34d97e0 | 2010-07-14 14:12:16 +1000 | [diff] [blame] | 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 | |
| 73 | 1: /* 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 |
| 83 | 1: PPC_WAIT(0) |
| 84 | b 1b |
| 85 | |
| 86 | #endif /* CONFIG_PPC64 */ |