forked from Minki/linux
97eb001f03
During "Fast-sleep" and deeper power savings state, decrementer and timebase could be stopped making it out of sync with rest of the cores in the system. Add a firmware call to request platform to resync timebase using low level platform methods. Signed-off-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com> Signed-off-by: Preeti U. Murthy <preeti@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
179 lines
3.7 KiB
ArmAsm
179 lines
3.7 KiB
ArmAsm
/*
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* This file contains the power_save function for Power7 CPUs.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License
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* as published by the Free Software Foundation; either version
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* 2 of the License, or (at your option) any later version.
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*/
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#include <linux/threads.h>
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#include <asm/processor.h>
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#include <asm/page.h>
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#include <asm/cputable.h>
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#include <asm/thread_info.h>
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#include <asm/ppc_asm.h>
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#include <asm/asm-offsets.h>
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#include <asm/ppc-opcode.h>
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#include <asm/hw_irq.h>
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#include <asm/kvm_book3s_asm.h>
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#include <asm/opal.h>
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#undef DEBUG
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/* Idle state entry routines */
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#define IDLE_STATE_ENTER_SEQ(IDLE_INST) \
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/* Magic NAP/SLEEP/WINKLE mode enter sequence */ \
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std r0,0(r1); \
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ptesync; \
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ld r0,0(r1); \
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1: cmp cr0,r0,r0; \
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bne 1b; \
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IDLE_INST; \
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b .
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.text
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/*
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* Pass requested state in r3:
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* 0 - nap
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* 1 - sleep
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*/
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_GLOBAL(power7_powersave_common)
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/* Use r3 to pass state nap/sleep/winkle */
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/* NAP is a state loss, we create a regs frame on the
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* stack, fill it up with the state we care about and
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* stick a pointer to it in PACAR1. We really only
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* need to save PC, some CR bits and the NV GPRs,
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* but for now an interrupt frame will do.
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*/
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mflr r0
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std r0,16(r1)
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stdu r1,-INT_FRAME_SIZE(r1)
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std r0,_LINK(r1)
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std r0,_NIP(r1)
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#ifndef CONFIG_SMP
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/* Make sure FPU, VSX etc... are flushed as we may lose
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* state when going to nap mode
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*/
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bl .discard_lazy_cpu_state
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#endif /* CONFIG_SMP */
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/* Hard disable interrupts */
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mfmsr r9
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rldicl r9,r9,48,1
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rotldi r9,r9,16
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mtmsrd r9,1 /* hard-disable interrupts */
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/* Check if something happened while soft-disabled */
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lbz r0,PACAIRQHAPPENED(r13)
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cmpwi cr0,r0,0
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beq 1f
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addi r1,r1,INT_FRAME_SIZE
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ld r0,16(r1)
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mtlr r0
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blr
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1: /* We mark irqs hard disabled as this is the state we'll
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* be in when returning and we need to tell arch_local_irq_restore()
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* about it
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*/
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li r0,PACA_IRQ_HARD_DIS
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stb r0,PACAIRQHAPPENED(r13)
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/* We haven't lost state ... yet */
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li r0,0
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stb r0,PACA_NAPSTATELOST(r13)
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/* Continue saving state */
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SAVE_GPR(2, r1)
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SAVE_NVGPRS(r1)
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mfcr r4
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std r4,_CCR(r1)
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std r9,_MSR(r1)
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std r1,PACAR1(r13)
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_GLOBAL(power7_enter_nap_mode)
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#ifdef CONFIG_KVM_BOOK3S_HV_POSSIBLE
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/* Tell KVM we're napping */
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li r4,KVM_HWTHREAD_IN_NAP
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stb r4,HSTATE_HWTHREAD_STATE(r13)
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#endif
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cmpwi cr0,r3,1
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beq 2f
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IDLE_STATE_ENTER_SEQ(PPC_NAP)
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/* No return */
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2: IDLE_STATE_ENTER_SEQ(PPC_SLEEP)
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/* No return */
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_GLOBAL(power7_idle)
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/* Now check if user or arch enabled NAP mode */
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LOAD_REG_ADDRBASE(r3,powersave_nap)
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lwz r4,ADDROFF(powersave_nap)(r3)
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cmpwi 0,r4,0
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beqlr
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/* fall through */
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_GLOBAL(power7_nap)
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li r3,0
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b power7_powersave_common
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/* No return */
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_GLOBAL(power7_sleep)
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li r3,1
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b power7_powersave_common
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/* No return */
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_GLOBAL(power7_wakeup_tb_loss)
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ld r2,PACATOC(r13);
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ld r1,PACAR1(r13)
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/* Time base re-sync */
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li r0,OPAL_RESYNC_TIMEBASE
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LOAD_REG_ADDR(r11,opal);
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ld r12,8(r11);
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ld r2,0(r11);
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mtctr r12
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bctrl
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/* TODO: Check r3 for failure */
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REST_NVGPRS(r1)
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REST_GPR(2, r1)
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ld r3,_CCR(r1)
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ld r4,_MSR(r1)
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ld r5,_NIP(r1)
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addi r1,r1,INT_FRAME_SIZE
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mtcr r3
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mfspr r3,SPRN_SRR1 /* Return SRR1 */
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mtspr SPRN_SRR1,r4
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mtspr SPRN_SRR0,r5
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rfid
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_GLOBAL(power7_wakeup_loss)
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ld r1,PACAR1(r13)
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REST_NVGPRS(r1)
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REST_GPR(2, r1)
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ld r3,_CCR(r1)
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ld r4,_MSR(r1)
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ld r5,_NIP(r1)
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addi r1,r1,INT_FRAME_SIZE
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mtcr r3
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mtspr SPRN_SRR1,r4
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mtspr SPRN_SRR0,r5
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rfid
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_GLOBAL(power7_wakeup_noloss)
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lbz r0,PACA_NAPSTATELOST(r13)
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cmpwi r0,0
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bne .power7_wakeup_loss
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ld r1,PACAR1(r13)
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ld r4,_MSR(r1)
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ld r5,_NIP(r1)
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addi r1,r1,INT_FRAME_SIZE
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mtspr SPRN_SRR1,r4
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mtspr SPRN_SRR0,r5
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rfid
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