| Linus Torvalds | 1da177e | 2005-04-16 15:20:36 -0700 | [diff] [blame] | 1 | /* |
| 2 | * This file contains the power_save function for 6xx & 7xxx CPUs |
| 3 | * rewritten in assembler |
| 4 | * |
| 5 | * Warning ! This code assumes that if your machine has a 750fx |
| 6 | * it will have PLL 1 set to low speed mode (used during NAP/DOZE). |
| 7 | * if this is not the case some additional changes will have to |
| 8 | * be done to check a runtime var (a bit like powersave-nap) |
| 9 | * |
| 10 | * This program is free software; you can redistribute it and/or |
| 11 | * modify it under the terms of the GNU General Public License |
| 12 | * as published by the Free Software Foundation; either version |
| 13 | * 2 of the License, or (at your option) any later version. |
| 14 | */ |
| 15 | |
| 16 | #include <linux/config.h> |
| 17 | #include <linux/threads.h> |
| 18 | #include <asm/processor.h> |
| 19 | #include <asm/page.h> |
| 20 | #include <asm/cputable.h> |
| 21 | #include <asm/thread_info.h> |
| 22 | #include <asm/ppc_asm.h> |
| 23 | #include <asm/offsets.h> |
| 24 | |
| 25 | #undef DEBUG |
| 26 | |
| 27 | .text |
| 28 | |
| 29 | /* |
| 30 | * Here is the power_save_6xx function. This could eventually be |
| 31 | * split into several functions & changing the function pointer |
| 32 | * depending on the various features. |
| 33 | */ |
| 34 | _GLOBAL(power4_idle) |
| 35 | BEGIN_FTR_SECTION |
| 36 | blr |
| 37 | END_FTR_SECTION_IFCLR(CPU_FTR_CAN_NAP) |
| 38 | /* We must dynamically check for the NAP feature as it |
| 39 | * can be cleared by CPU init after the fixups are done |
| 40 | */ |
| 41 | LOADBASE(r3,cur_cpu_spec) |
| 42 | ld r4,cur_cpu_spec@l(r3) |
| 43 | ld r4,CPU_SPEC_FEATURES(r4) |
| 44 | andi. r0,r4,CPU_FTR_CAN_NAP |
| 45 | beqlr |
| 46 | /* Now check if user or arch enabled NAP mode */ |
| 47 | LOADBASE(r3,powersave_nap) |
| 48 | lwz r4,powersave_nap@l(r3) |
| 49 | cmpwi 0,r4,0 |
| 50 | beqlr |
| 51 | |
| 52 | /* Clear MSR:EE */ |
| 53 | mfmsr r7 |
| 54 | li r4,0 |
| 55 | ori r4,r4,MSR_EE |
| 56 | andc r0,r7,r4 |
| 57 | mtmsrd r0 |
| 58 | |
| 59 | /* Check current_thread_info()->flags */ |
| 60 | clrrdi r4,r1,THREAD_SHIFT |
| 61 | ld r4,TI_FLAGS(r4) |
| 62 | andi. r0,r4,_TIF_NEED_RESCHED |
| 63 | beq 1f |
| 64 | mtmsrd r7 /* out of line this ? */ |
| 65 | blr |
| 66 | 1: |
| 67 | /* Go to NAP now */ |
| 68 | BEGIN_FTR_SECTION |
| 69 | DSSALL |
| 70 | sync |
| 71 | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) |
| 72 | oris r7,r7,MSR_POW@h |
| 73 | sync |
| 74 | isync |
| 75 | mtmsrd r7 |
| 76 | isync |
| 77 | sync |
| 78 | blr |
| 79 | |