diff options
Diffstat (limited to 'arch/powerpc/kernel/idle_power4.S')
| -rw-r--r-- | arch/powerpc/kernel/idle_power4.S | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/idle_power4.S b/arch/powerpc/kernel/idle_power4.S new file mode 100644 index 000000000..a09b3c7ca --- /dev/null +++ b/arch/powerpc/kernel/idle_power4.S @@ -0,0 +1,87 @@ +/* + * 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 |