Kumar Gala | fc4033b | 2008-06-18 16:26:52 -0500 | [diff] [blame] | 1 | /* |
| 2 | * Copyright (C) 2008 Freescale Semiconductor, Inc. All rights reserved. |
| 3 | * Dave Liu <daveliu@freescale.com> |
| 4 | * copy from idle_6xx.S and modify for e500 based processor, |
| 5 | * implement the power_save function in idle. |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version |
| 10 | * 2 of the License, or (at your option) any later version. |
| 11 | */ |
| 12 | |
| 13 | #include <linux/threads.h> |
| 14 | #include <asm/reg.h> |
| 15 | #include <asm/page.h> |
| 16 | #include <asm/cputable.h> |
| 17 | #include <asm/thread_info.h> |
| 18 | #include <asm/ppc_asm.h> |
| 19 | #include <asm/asm-offsets.h> |
| 20 | |
| 21 | .text |
| 22 | |
| 23 | _GLOBAL(e500_idle) |
Stuart Yoder | 9778b69 | 2012-07-05 04:41:35 +0000 | [diff] [blame] | 24 | CURRENT_THREAD_INFO(r3, r1) |
Kumar Gala | fc4033b | 2008-06-18 16:26:52 -0500 | [diff] [blame] | 25 | lwz r4,TI_LOCAL_FLAGS(r3) /* set napping bit */ |
| 26 | ori r4,r4,_TLF_NAPPING /* so when we take an exception */ |
| 27 | stw r4,TI_LOCAL_FLAGS(r3) /* it will return to our caller */ |
| 28 | |
Bharat Bhushan | e33ee8b | 2011-10-11 11:26:08 +0530 | [diff] [blame] | 29 | #ifdef CONFIG_PPC_E500MC |
Scott Wood | ebf714f | 2011-06-22 18:10:30 -0500 | [diff] [blame] | 30 | wrteei 1 |
| 31 | 1: wait |
| 32 | |
| 33 | /* |
| 34 | * Guard against spurious wakeups (e.g. from a hypervisor) -- |
| 35 | * any real interrupt will cause us to return to LR due to |
| 36 | * _TLF_NAPPING. |
| 37 | */ |
| 38 | b 1b |
| 39 | #else |
Kumar Gala | fc4033b | 2008-06-18 16:26:52 -0500 | [diff] [blame] | 40 | /* Check if we can nap or doze, put HID0 mask in r3 */ |
| 41 | lis r3,0 |
| 42 | BEGIN_FTR_SECTION |
| 43 | lis r3,HID0_DOZE@h |
| 44 | END_FTR_SECTION_IFSET(CPU_FTR_CAN_DOZE) |
| 45 | |
| 46 | BEGIN_FTR_SECTION |
| 47 | /* Now check if user enabled NAP mode */ |
| 48 | lis r4,powersave_nap@ha |
| 49 | lwz r4,powersave_nap@l(r4) |
| 50 | cmpwi 0,r4,0 |
| 51 | beq 1f |
| 52 | stwu r1,-16(r1) |
| 53 | mflr r0 |
| 54 | stw r0,20(r1) |
| 55 | bl flush_dcache_L1 |
| 56 | lwz r0,20(r1) |
| 57 | addi r1,r1,16 |
| 58 | mtlr r0 |
| 59 | lis r3,HID0_NAP@h |
| 60 | END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP) |
Kumar Gala | aba11fc | 2008-06-19 09:40:31 -0500 | [diff] [blame] | 61 | BEGIN_FTR_SECTION |
| 62 | msync |
| 63 | li r7,L2CSR0_L2FL@l |
| 64 | mtspr SPRN_L2CSR0,r7 |
| 65 | 2: |
| 66 | mfspr r7,SPRN_L2CSR0 |
| 67 | andi. r4,r7,L2CSR0_L2FL@l |
| 68 | bne 2b |
| 69 | END_FTR_SECTION_IFSET(CPU_FTR_L2CSR|CPU_FTR_CAN_NAP) |
Kumar Gala | fc4033b | 2008-06-18 16:26:52 -0500 | [diff] [blame] | 70 | 1: |
| 71 | /* Go to NAP or DOZE now */ |
| 72 | mfspr r4,SPRN_HID0 |
| 73 | rlwinm r4,r4,0,~(HID0_DOZE|HID0_NAP|HID0_SLEEP) |
| 74 | or r4,r4,r3 |
| 75 | isync |
| 76 | mtspr SPRN_HID0,r4 |
| 77 | isync |
| 78 | |
| 79 | mfmsr r7 |
| 80 | oris r7,r7,MSR_WE@h |
| 81 | ori r7,r7,MSR_EE |
| 82 | msync |
| 83 | mtmsr r7 |
| 84 | isync |
| 85 | 2: b 2b |
Scott Wood | ebf714f | 2011-06-22 18:10:30 -0500 | [diff] [blame] | 86 | #endif /* !E500MC */ |
Kumar Gala | fc4033b | 2008-06-18 16:26:52 -0500 | [diff] [blame] | 87 | |
| 88 | /* |
| 89 | * Return from NAP/DOZE mode, restore some CPU specific registers, |
| 90 | * r2 containing physical address of current. |
| 91 | * r11 points to the exception frame (physical address). |
| 92 | * We have to preserve r10. |
| 93 | */ |
| 94 | _GLOBAL(power_save_ppc32_restore) |
| 95 | lwz r9,_LINK(r11) /* interrupted in e500_idle */ |
| 96 | stw r9,_NIP(r11) /* make it do a blr */ |
| 97 | |
| 98 | #ifdef CONFIG_SMP |
Stuart Yoder | 9778b69 | 2012-07-05 04:41:35 +0000 | [diff] [blame] | 99 | CURRENT_THREAD_INFO(r12, r1) |
Kumar Gala | fc4033b | 2008-06-18 16:26:52 -0500 | [diff] [blame] | 100 | lwz r11,TI_CPU(r12) /* get cpu number * 4 */ |
| 101 | slwi r11,r11,2 |
| 102 | #else |
| 103 | li r11,0 |
| 104 | #endif |
Kumar Gala | 7888bc2 | 2008-08-26 12:08:56 +1000 | [diff] [blame] | 105 | |
Kumar Gala | fc4033b | 2008-06-18 16:26:52 -0500 | [diff] [blame] | 106 | b transfer_to_handler_cont |