| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * This file contains the power_save function for 970-family CPUs. |
| */ |
| |
| #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) |
| ld r9, PACA_THREAD_INFO(r13) |
| 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 |
