Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 1 | /* |
Benjamin Herrenschmidt | 7230c56 | 2012-03-06 18:27:59 +1100 | [diff] [blame] | 2 | * This file contains the power_save function for Power7 CPUs. |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation; either version |
| 7 | * 2 of the License, or (at your option) any later version. |
| 8 | */ |
| 9 | |
| 10 | #include <linux/threads.h> |
| 11 | #include <asm/processor.h> |
| 12 | #include <asm/page.h> |
| 13 | #include <asm/cputable.h> |
| 14 | #include <asm/thread_info.h> |
| 15 | #include <asm/ppc_asm.h> |
| 16 | #include <asm/asm-offsets.h> |
| 17 | #include <asm/ppc-opcode.h> |
Benjamin Herrenschmidt | 7230c56 | 2012-03-06 18:27:59 +1100 | [diff] [blame] | 18 | #include <asm/hw_irq.h> |
Paul Mackerras | f0888f7 | 2012-02-03 00:54:17 +0000 | [diff] [blame] | 19 | #include <asm/kvm_book3s_asm.h> |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 20 | |
| 21 | #undef DEBUG |
| 22 | |
| 23 | .text |
| 24 | |
| 25 | _GLOBAL(power7_idle) |
| 26 | /* Now check if user or arch enabled NAP mode */ |
| 27 | LOAD_REG_ADDRBASE(r3,powersave_nap) |
| 28 | lwz r4,ADDROFF(powersave_nap)(r3) |
| 29 | cmpwi 0,r4,0 |
| 30 | beqlr |
Paul Mackerras | 375f561 | 2012-07-26 18:51:09 +0000 | [diff] [blame] | 31 | /* fall through */ |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 32 | |
Paul Mackerras | 375f561 | 2012-07-26 18:51:09 +0000 | [diff] [blame] | 33 | _GLOBAL(power7_nap) |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 34 | /* NAP is a state loss, we create a regs frame on the |
| 35 | * stack, fill it up with the state we care about and |
| 36 | * stick a pointer to it in PACAR1. We really only |
| 37 | * need to save PC, some CR bits and the NV GPRs, |
| 38 | * but for now an interrupt frame will do. |
| 39 | */ |
| 40 | mflr r0 |
| 41 | std r0,16(r1) |
| 42 | stdu r1,-INT_FRAME_SIZE(r1) |
| 43 | std r0,_LINK(r1) |
| 44 | std r0,_NIP(r1) |
| 45 | |
| 46 | #ifndef CONFIG_SMP |
| 47 | /* Make sure FPU, VSX etc... are flushed as we may lose |
| 48 | * state when going to nap mode |
| 49 | */ |
| 50 | bl .discard_lazy_cpu_state |
| 51 | #endif /* CONFIG_SMP */ |
| 52 | |
| 53 | /* Hard disable interrupts */ |
| 54 | mfmsr r9 |
| 55 | rldicl r9,r9,48,1 |
| 56 | rotldi r9,r9,16 |
| 57 | mtmsrd r9,1 /* hard-disable interrupts */ |
Benjamin Herrenschmidt | 7230c56 | 2012-03-06 18:27:59 +1100 | [diff] [blame] | 58 | |
| 59 | /* Check if something happened while soft-disabled */ |
| 60 | lbz r0,PACAIRQHAPPENED(r13) |
| 61 | cmpwi cr0,r0,0 |
| 62 | beq 1f |
| 63 | addi r1,r1,INT_FRAME_SIZE |
| 64 | ld r0,16(r1) |
| 65 | mtlr r0 |
| 66 | blr |
| 67 | |
| 68 | 1: /* We mark irqs hard disabled as this is the state we'll |
| 69 | * be in when returning and we need to tell arch_local_irq_restore() |
| 70 | * about it |
| 71 | */ |
| 72 | li r0,PACA_IRQ_HARD_DIS |
| 73 | stb r0,PACAIRQHAPPENED(r13) |
| 74 | |
| 75 | /* We haven't lost state ... yet */ |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 76 | li r0,0 |
Paul Mackerras | 2fde6d2 | 2011-12-05 19:47:26 +0000 | [diff] [blame] | 77 | stb r0,PACA_NAPSTATELOST(r13) |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 78 | |
| 79 | /* Continue saving state */ |
| 80 | SAVE_GPR(2, r1) |
| 81 | SAVE_NVGPRS(r1) |
| 82 | mfcr r3 |
| 83 | std r3,_CCR(r1) |
| 84 | std r9,_MSR(r1) |
| 85 | std r1,PACAR1(r13) |
| 86 | |
Paul Mackerras | f0888f7 | 2012-02-03 00:54:17 +0000 | [diff] [blame] | 87 | #ifdef CONFIG_KVM_BOOK3S_64_HV |
| 88 | /* Tell KVM we're napping */ |
| 89 | li r4,KVM_HWTHREAD_IN_NAP |
| 90 | stb r4,HSTATE_HWTHREAD_STATE(r13) |
| 91 | #endif |
| 92 | |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 93 | /* Magic NAP mode enter sequence */ |
| 94 | std r0,0(r1) |
| 95 | ptesync |
| 96 | ld r0,0(r1) |
| 97 | 1: cmp cr0,r0,r0 |
| 98 | bne 1b |
| 99 | PPC_NAP |
| 100 | b . |
| 101 | |
| 102 | _GLOBAL(power7_wakeup_loss) |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 103 | ld r1,PACAR1(r13) |
| 104 | REST_NVGPRS(r1) |
| 105 | REST_GPR(2, r1) |
| 106 | ld r3,_CCR(r1) |
| 107 | ld r4,_MSR(r1) |
| 108 | ld r5,_NIP(r1) |
| 109 | addi r1,r1,INT_FRAME_SIZE |
| 110 | mtcr r3 |
| 111 | mtspr SPRN_SRR1,r4 |
| 112 | mtspr SPRN_SRR0,r5 |
| 113 | rfid |
| 114 | |
| 115 | _GLOBAL(power7_wakeup_noloss) |
Paul Mackerras | 2fde6d2 | 2011-12-05 19:47:26 +0000 | [diff] [blame] | 116 | lbz r0,PACA_NAPSTATELOST(r13) |
| 117 | cmpwi r0,0 |
| 118 | bne .power7_wakeup_loss |
Benjamin Herrenschmidt | 948cf67 | 2011-01-24 18:42:41 +1100 | [diff] [blame] | 119 | ld r1,PACAR1(r13) |
| 120 | ld r4,_MSR(r1) |
| 121 | ld r5,_NIP(r1) |
| 122 | addi r1,r1,INT_FRAME_SIZE |
| 123 | mtspr SPRN_SRR1,r4 |
| 124 | mtspr SPRN_SRR0,r5 |
| 125 | rfid |