948cf67c47
Wakeup comes from the system reset handler with a potential loss of the non-hypervisor CPU state. We save the non-volatile state on the stack and a pointer to it in the PACA, which the system reset handler uses to restore things Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
98 lines
2.1 KiB
ArmAsm
98 lines
2.1 KiB
ArmAsm
/*
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* This file contains the power_save function for 970-family 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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#undef DEBUG
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.text
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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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/* 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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li r0,0
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stb r0,PACASOFTIRQEN(r13) /* we'll hard-enable shortly */
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stb r0,PACAHARDIRQEN(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 r3
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std r3,_CCR(r1)
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std r9,_MSR(r1)
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std r1,PACAR1(r13)
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/* Magic NAP 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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PPC_NAP
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b .
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_GLOBAL(power7_wakeup_loss)
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GET_PACA(r13)
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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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GET_PACA(r13)
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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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