diff options
Diffstat (limited to 'arch/powerpc/kernel/idle_64e.S')
| -rw-r--r-- | arch/powerpc/kernel/idle_64e.S | 99 |
1 files changed, 99 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/idle_64e.S b/arch/powerpc/kernel/idle_64e.S new file mode 100644 index 000000000..0fc680e03 --- /dev/null +++ b/arch/powerpc/kernel/idle_64e.S @@ -0,0 +1,99 @@ +/* SPDX-License-Identifier: GPL-2.0-or-later */ +/* + * Copyright 2010 IBM Corp, Benjamin Herrenschmidt <benh@kernel.crashing.org> + * + * Generic idle routine for 64 bits e500 processors + */ + +#include <linux/threads.h> +#include <asm/reg.h> +#include <asm/ppc_asm.h> +#include <asm/asm-offsets.h> +#include <asm/ppc-opcode.h> +#include <asm/processor.h> +#include <asm/thread_info.h> +#include <asm/epapr_hcalls.h> +#include <asm/hw_irq.h> + +/* 64-bit version only for now */ +.macro BOOK3E_IDLE name loop +_GLOBAL(\name) + /* Save LR for later */ + mflr r0 + std r0,16(r1) + + /* Hard disable interrupts */ + wrteei 0 + + /* Now check if an interrupt came in while we were soft disabled + * since we may otherwise lose it (doorbells etc...). + */ + lbz r3,PACAIRQHAPPENED(r13) + cmpwi cr0,r3,0 + bne 2f + + /* Now we are going to mark ourselves as soft and hard enabled in + * order to be able to take interrupts while asleep. We inform lockdep + * of that. We don't actually turn interrupts on just yet tho. + */ +#ifdef CONFIG_TRACE_IRQFLAGS + stdu r1,-128(r1) + bl trace_hardirqs_on + addi r1,r1,128 +#endif + li r0,IRQS_ENABLED + stb r0,PACAIRQSOFTMASK(r13) + + /* Interrupts will make use return to LR, so get something we want + * in there + */ + bl 1f + + /* And return (interrupts are on) */ + ld r0,16(r1) + mtlr r0 + blr + +1: /* Let's set the _TLF_NAPPING flag so interrupts make us return + * to the right spot + */ + ld r11, PACACURRENT(r13) + ld r10,TI_LOCAL_FLAGS(r11) + ori r10,r10,_TLF_NAPPING + std r10,TI_LOCAL_FLAGS(r11) + + /* We can now re-enable hard interrupts and go to sleep */ + wrteei 1 + \loop + +2: + lbz r10,PACAIRQHAPPENED(r13) + ori r10,r10,PACA_IRQ_HARD_DIS + stb r10,PACAIRQHAPPENED(r13) + blr +.endm + +.macro BOOK3E_IDLE_LOOP +1: + PPC_WAIT_v203 + b 1b +.endm + +/* epapr_ev_idle_start below is patched with the proper hcall + opcodes during kernel initialization */ +.macro EPAPR_EV_IDLE_LOOP +idle_loop: + LOAD_REG_IMMEDIATE(r11, EV_HCALL_TOKEN(EV_IDLE)) + +.global epapr_ev_idle_start +epapr_ev_idle_start: + li r3, -1 + nop + nop + nop + b idle_loop +.endm + +BOOK3E_IDLE epapr_ev_idle EPAPR_EV_IDLE_LOOP + +BOOK3E_IDLE e500_idle BOOK3E_IDLE_LOOP |