| /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| /* |
| * 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. |
| */ |
| |
| #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) |
