/* SPDX-License-Identifier: GPL-2.0-or-later */
/*
* Copyright (C) 2008 Freescale Semiconductor, Inc. All rights reserved.
* Dave Liu <[email protected]>
* copy from idle_6xx.S and modify for e500 based processor,
* implement the power_save function in idle.
*/
#include <linux/threads.h>
#include <asm/reg.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/feature-fixups.h>
.text
_GLOBAL(e500_idle)
lwz r4,TI_LOCAL_FLAGS(r2) /* set napping bit */
ori r4,r4,_TLF_NAPPING /* so when we take an exception */
stw r4,TI_LOCAL_FLAGS(r2) /* it will return to our caller */
#ifdef CONFIG_PPC_E500MC
wrteei 1
1: wait
/*
* Guard against spurious wakeups (e.g. from a hypervisor) --
* any real interrupt will cause us to return to LR due to
* _TLF_NAPPING.
*/
b 1b
#else
/* Check if we can nap or doze, put HID0 mask in r3 */
lis r3,0
BEGIN_FTR_SECTION
lis r3,HID0_DOZE@h
END_FTR_SECTION_IFSET(CPU_FTR_CAN_DOZE)
BEGIN_FTR_SECTION
/* Now check if user enabled NAP mode */
lis r4,powersave_nap@ha
lwz r4,powersave_nap@l(r4)
cmpwi 0,r4,0
beq 1f
stwu r1,-16(r1)
mflr r0
stw r0,20(r1)
bl flush_dcache_L1
lwz r0,20(r1)
addi r1,r1,16
mtlr r0
lis r3,HID0_NAP@h
END_FTR_SECTION_IFSET(CPU_FTR_CAN_NAP)
1:
/* Go to NAP or DOZE now */
mfspr r4,SPRN_HID0
rlwinm r4,r4,0,~(HID0_DOZE|HID0_NAP|HID0_SLEEP)
or r4,r4,r3
isync
mtspr SPRN_HID0,r4
isync
mfmsr r7
oris r7,r7,MSR_WE@h
ori r7,r7,MSR_EE
msync
mtmsr r7
isync
2: b 2b
#endif /* !E500MC */
/*
* Return from NAP/DOZE mode, restore some CPU specific registers,
* r2 containing address of current.
* r11 points to the exception frame.
* We have to preserve r10.
*/
_GLOBAL(power_save_ppc32_restore)
lwz r9,_LINK(r11) /* interrupted in e500_idle */
stw r9,_NIP(r11) /* make it do a blr */
blr
_ASM_NOKPROBE_SYMBOL(power_save_ppc32_restore)
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