/* * Copyright (C) 2008 Freescale Semiconductor, Inc. All rights reserved. * Dave Liu <daveliu@freescale.com> * copy from idle_6xx.S and modify for e500 based processor, * implement the power_save function in idle. * * 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/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> .text _GLOBAL(e500_idle) CURRENT_THREAD_INFO(r3, r1) lwz r4,TI_LOCAL_FLAGS(r3) /* set napping bit */ ori r4,r4,_TLF_NAPPING /* so when we take an exception */ stw r4,TI_LOCAL_FLAGS(r3) /* 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 physical address of current. * r11 points to the exception frame (physical address). * 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 */ #ifdef CONFIG_SMP CURRENT_THREAD_INFO(r12, r1) lwz r11,TI_CPU(r12) /* get cpu number * 4 */ slwi r11,r11,2 #else li r11,0 #endif b transfer_to_handler_cont