1/* 2 * Copyright 2010 Tilera Corporation. All Rights Reserved. 3 * 4 * This program is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU General Public License 6 * as published by the Free Software Foundation, version 2. 7 * 8 * This program is distributed in the hope that it will be useful, but 9 * WITHOUT ANY WARRANTY; without even the implied warranty of 10 * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or 11 * NON INFRINGEMENT. See the GNU General Public License for 12 * more details. 13 */ 14 15#include <linux/linkage.h> 16#include <linux/unistd.h> 17#include <asm/irqflags.h> 18#include <asm/processor.h> 19#include <arch/abi.h> 20#include <arch/spr_def.h> 21 22#ifdef __tilegx__ 23#define bnzt bnezt 24#endif 25 26STD_ENTRY(current_text_addr) 27 { move r0, lr; jrp lr } 28 STD_ENDPROC(current_text_addr) 29 30STD_ENTRY(dump_stack) 31 { move r2, lr; lnk r1 } 32 { move r4, r52; addli r1, r1, dump_stack - . } 33 { move r3, sp; j _dump_stack } 34 jrp lr /* keep backtracer happy */ 35 STD_ENDPROC(dump_stack) 36 37STD_ENTRY(KBacktraceIterator_init_current) 38 { move r2, lr; lnk r1 } 39 { move r4, r52; addli r1, r1, KBacktraceIterator_init_current - . } 40 { move r3, sp; j _KBacktraceIterator_init_current } 41 jrp lr /* keep backtracer happy */ 42 STD_ENDPROC(KBacktraceIterator_init_current) 43 44/* Loop forever on a nap during SMP boot. */ 45STD_ENTRY(smp_nap) 46 nap 47 nop /* avoid provoking the icache prefetch with a jump */ 48 j smp_nap /* we are not architecturally guaranteed not to exit nap */ 49 jrp lr /* clue in the backtracer */ 50 STD_ENDPROC(smp_nap) 51 52/* 53 * Enable interrupts racelessly and then nap until interrupted. 54 * Architecturally, we are guaranteed that enabling interrupts via 55 * mtspr to INTERRUPT_CRITICAL_SECTION only interrupts at the next PC. 56 * This function's _cpu_idle_nap address is special; see intvec.S. 57 * When interrupted at _cpu_idle_nap, we bump the PC forward 8, and 58 * as a result return to the function that called _cpu_idle(). 59 */ 60STD_ENTRY(_cpu_idle) 61 movei r1, 1 62 IRQ_ENABLE_LOAD(r2, r3) 63 mtspr INTERRUPT_CRITICAL_SECTION, r1 64 IRQ_ENABLE_APPLY(r2, r3) /* unmask, but still with ICS set */ 65 mtspr INTERRUPT_CRITICAL_SECTION, zero 66 .global _cpu_idle_nap 67_cpu_idle_nap: 68 nap 69 nop /* avoid provoking the icache prefetch with a jump */ 70 jrp lr 71 STD_ENDPROC(_cpu_idle) 72