| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 1 | /* SPDX-License-Identifier: GPL-2.0-or-later */ |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 2 | /* |
| 3 | * Copyright 2010 IBM Corp, Benjamin Herrenschmidt <benh@kernel.crashing.org> |
| 4 | * |
| 5 | * Generic idle routine for Book3E processors |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 6 | */ |
| 7 | |
| 8 | #include <linux/threads.h> |
| 9 | #include <asm/reg.h> |
| 10 | #include <asm/ppc_asm.h> |
| 11 | #include <asm/asm-offsets.h> |
| 12 | #include <asm/ppc-opcode.h> |
| 13 | #include <asm/processor.h> |
| 14 | #include <asm/thread_info.h> |
| 15 | #include <asm/epapr_hcalls.h> |
| 16 | #include <asm/hw_irq.h> |
| 17 | |
| 18 | /* 64-bit version only for now */ |
| 19 | #ifdef CONFIG_PPC64 |
| 20 | |
| 21 | .macro BOOK3E_IDLE name loop |
| 22 | _GLOBAL(\name) |
| 23 | /* Save LR for later */ |
| 24 | mflr r0 |
| 25 | std r0,16(r1) |
| 26 | |
| 27 | /* Hard disable interrupts */ |
| 28 | wrteei 0 |
| 29 | |
| 30 | /* Now check if an interrupt came in while we were soft disabled |
| 31 | * since we may otherwise lose it (doorbells etc...). |
| 32 | */ |
| 33 | lbz r3,PACAIRQHAPPENED(r13) |
| 34 | cmpwi cr0,r3,0 |
| 35 | bne 2f |
| 36 | |
| 37 | /* Now we are going to mark ourselves as soft and hard enabled in |
| 38 | * order to be able to take interrupts while asleep. We inform lockdep |
| 39 | * of that. We don't actually turn interrupts on just yet tho. |
| 40 | */ |
| 41 | #ifdef CONFIG_TRACE_IRQFLAGS |
| 42 | stdu r1,-128(r1) |
| 43 | bl trace_hardirqs_on |
| 44 | addi r1,r1,128 |
| 45 | #endif |
| 46 | li r0,IRQS_ENABLED |
| 47 | stb r0,PACAIRQSOFTMASK(r13) |
| 48 | |
| 49 | /* Interrupts will make use return to LR, so get something we want |
| 50 | * in there |
| 51 | */ |
| 52 | bl 1f |
| 53 | |
| 54 | /* And return (interrupts are on) */ |
| 55 | ld r0,16(r1) |
| 56 | mtlr r0 |
| 57 | blr |
| 58 | |
| 59 | 1: /* Let's set the _TLF_NAPPING flag so interrupts make us return |
| 60 | * to the right spot |
| 61 | */ |
| David Brazdil | 0f672f6 | 2019-12-10 10:32:29 +0000 | [diff] [blame^] | 62 | ld r11, PACACURRENT(r13) |
| Andrew Scull | b4b6d4a | 2019-01-02 15:54:55 +0000 | [diff] [blame] | 63 | ld r10,TI_LOCAL_FLAGS(r11) |
| 64 | ori r10,r10,_TLF_NAPPING |
| 65 | std r10,TI_LOCAL_FLAGS(r11) |
| 66 | |
| 67 | /* We can now re-enable hard interrupts and go to sleep */ |
| 68 | wrteei 1 |
| 69 | \loop |
| 70 | |
| 71 | 2: |
| 72 | lbz r10,PACAIRQHAPPENED(r13) |
| 73 | ori r10,r10,PACA_IRQ_HARD_DIS |
| 74 | stb r10,PACAIRQHAPPENED(r13) |
| 75 | blr |
| 76 | .endm |
| 77 | |
| 78 | .macro BOOK3E_IDLE_LOOP |
| 79 | 1: |
| 80 | PPC_WAIT(0) |
| 81 | b 1b |
| 82 | .endm |
| 83 | |
| 84 | /* epapr_ev_idle_start below is patched with the proper hcall |
| 85 | opcodes during kernel initialization */ |
| 86 | .macro EPAPR_EV_IDLE_LOOP |
| 87 | idle_loop: |
| 88 | LOAD_REG_IMMEDIATE(r11, EV_HCALL_TOKEN(EV_IDLE)) |
| 89 | |
| 90 | .global epapr_ev_idle_start |
| 91 | epapr_ev_idle_start: |
| 92 | li r3, -1 |
| 93 | nop |
| 94 | nop |
| 95 | nop |
| 96 | b idle_loop |
| 97 | .endm |
| 98 | |
| 99 | BOOK3E_IDLE epapr_ev_idle EPAPR_EV_IDLE_LOOP |
| 100 | |
| 101 | BOOK3E_IDLE book3e_idle BOOK3E_IDLE_LOOP |
| 102 | |
| 103 | #endif /* CONFIG_PPC64 */ |