/*
|
* This file contains the power_save function for 970-family 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/irqflags.h>
|
#include <asm/hw_irq.h>
|
#include <asm/feature-fixups.h>
|
|
#undef DEBUG
|
|
.text
|
|
_GLOBAL(power4_idle)
|
BEGIN_FTR_SECTION
|
blr
|
END_FTR_SECTION_IFCLR(CPU_FTR_CAN_NAP)
|
/* 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
|
|
/* This sequence is similar to prep_irq_for_idle() */
|
|
/* Hard disable interrupts */
|
mfmsr r7
|
rldicl r0,r7,48,1
|
rotldi r0,r0,16
|
mtmsrd r0,1
|
|
/* Check if something happened while soft-disabled */
|
lbz r0,PACAIRQHAPPENED(r13)
|
cmpwi cr0,r0,0
|
bne- 2f
|
|
/*
|
* Soft-enable interrupts. This will make power4_fixup_nap return
|
* to our caller with interrupts enabled (soft and hard). The caller
|
* can cope with either interrupts disabled or enabled upon return.
|
*/
|
#ifdef CONFIG_TRACE_IRQFLAGS
|
/* Tell the tracer interrupts are on, because idle responds to them. */
|
mflr r0
|
std r0,16(r1)
|
stdu r1,-128(r1)
|
bl trace_hardirqs_on
|
addi r1,r1,128
|
ld r0,16(r1)
|
mtlr r0
|
mfmsr r7
|
#endif /* CONFIG_TRACE_IRQFLAGS */
|
|
li r0,IRQS_ENABLED
|
stb r0,PACAIRQSOFTMASK(r13) /* we'll hard-enable shortly */
|
BEGIN_FTR_SECTION
|
DSSALL
|
sync
|
END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC)
|
CURRENT_THREAD_INFO(r9, r1)
|
ld r8,TI_LOCAL_FLAGS(r9) /* set napping bit */
|
ori r8,r8,_TLF_NAPPING /* so when we take an exception */
|
std r8,TI_LOCAL_FLAGS(r9) /* it will return to our caller */
|
ori r7,r7,MSR_EE
|
oris r7,r7,MSR_POW@h
|
1: sync
|
isync
|
mtmsrd r7
|
isync
|
b 1b
|
|
2: /* Return if an interrupt had happened while soft disabled */
|
/* Set the HARD_DIS flag because interrupts are now hard disabled */
|
ori r0,r0,PACA_IRQ_HARD_DIS
|
stb r0,PACAIRQHAPPENED(r13)
|
blr
|
