| /* |
| * This file contains the power_save function for Power7 CPUs. |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * as published by the Free Software Foundation; either version |
| * 2 of the License, or (at your option) any later version. |
| */ |
| |
| #include <linux/threads.h> |
| #include <asm/processor.h> |
| #include <asm/page.h> |
| #include <asm/cputable.h> |
| #include <asm/thread_info.h> |
| #include <asm/ppc_asm.h> |
| #include <asm/asm-offsets.h> |
| #include <asm/ppc-opcode.h> |
| #include <asm/hw_irq.h> |
| #include <asm/kvm_book3s_asm.h> |
| |
| #undef DEBUG |
| |
| .text |
| |
| _GLOBAL(power7_idle) |
| /* Now check if user or arch enabled NAP mode */ |
| LOAD_REG_ADDRBASE(r3,powersave_nap) |
| lwz r4,ADDROFF(powersave_nap)(r3) |
| cmpwi 0,r4,0 |
| beqlr |
| /* fall through */ |
| |
| _GLOBAL(power7_nap) |
| /* NAP is a state loss, we create a regs frame on the |
| * stack, fill it up with the state we care about and |
| * stick a pointer to it in PACAR1. We really only |
| * need to save PC, some CR bits and the NV GPRs, |
| * but for now an interrupt frame will do. |
| */ |
| mflr r0 |
| std r0,16(r1) |
| stdu r1,-INT_FRAME_SIZE(r1) |
| std r0,_LINK(r1) |
| std r0,_NIP(r1) |
| |
| #ifndef CONFIG_SMP |
| /* Make sure FPU, VSX etc... are flushed as we may lose |
| * state when going to nap mode |
| */ |
| bl .discard_lazy_cpu_state |
| #endif /* CONFIG_SMP */ |
| |
| /* Hard disable interrupts */ |
| mfmsr r9 |
| rldicl r9,r9,48,1 |
| rotldi r9,r9,16 |
| mtmsrd r9,1 /* hard-disable interrupts */ |
| |
| /* Check if something happened while soft-disabled */ |
| lbz r0,PACAIRQHAPPENED(r13) |
| cmpwi cr0,r0,0 |
| beq 1f |
| addi r1,r1,INT_FRAME_SIZE |
| ld r0,16(r1) |
| mtlr r0 |
| blr |
| |
| 1: /* We mark irqs hard disabled as this is the state we'll |
| * be in when returning and we need to tell arch_local_irq_restore() |
| * about it |
| */ |
| li r0,PACA_IRQ_HARD_DIS |
| stb r0,PACAIRQHAPPENED(r13) |
| |
| /* We haven't lost state ... yet */ |
| li r0,0 |
| stb r0,PACA_NAPSTATELOST(r13) |
| |
| /* Continue saving state */ |
| SAVE_GPR(2, r1) |
| SAVE_NVGPRS(r1) |
| mfcr r3 |
| std r3,_CCR(r1) |
| std r9,_MSR(r1) |
| std r1,PACAR1(r13) |
| |
| #ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE |
| /* Tell KVM we're napping */ |
| li r4,KVM_HWTHREAD_IN_NAP |
| stb r4,HSTATE_HWTHREAD_STATE(r13) |
| #endif |
| |
| /* Magic NAP mode enter sequence */ |
| std r0,0(r1) |
| ptesync |
| ld r0,0(r1) |
| 1: cmp cr0,r0,r0 |
| bne 1b |
| PPC_NAP |
| b . |
| |
| _GLOBAL(power7_wakeup_loss) |
| ld r1,PACAR1(r13) |
| REST_NVGPRS(r1) |
| REST_GPR(2, r1) |
| ld r3,_CCR(r1) |
| ld r4,_MSR(r1) |
| ld r5,_NIP(r1) |
| addi r1,r1,INT_FRAME_SIZE |
| mtcr r3 |
| mtspr SPRN_SRR1,r4 |
| mtspr SPRN_SRR0,r5 |
| rfid |
| |
| _GLOBAL(power7_wakeup_noloss) |
| lbz r0,PACA_NAPSTATELOST(r13) |
| cmpwi r0,0 |
| bne .power7_wakeup_loss |
| ld r1,PACAR1(r13) |
| ld r4,_MSR(r1) |
| ld r5,_NIP(r1) |
| addi r1,r1,INT_FRAME_SIZE |
| mtspr SPRN_SRR1,r4 |
| mtspr SPRN_SRR0,r5 |
| rfid |