diff options
Diffstat (limited to 'kernel/arch/tile/kernel/entry.S')
| -rw-r--r-- | kernel/arch/tile/kernel/entry.S | 71 |
1 files changed, 71 insertions, 0 deletions
diff --git a/kernel/arch/tile/kernel/entry.S b/kernel/arch/tile/kernel/entry.S new file mode 100644 index 000000000..3d9175992 --- /dev/null +++ b/kernel/arch/tile/kernel/entry.S @@ -0,0 +1,71 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * 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, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#include <linux/linkage.h> +#include <linux/unistd.h> +#include <asm/irqflags.h> +#include <asm/processor.h> +#include <arch/abi.h> +#include <arch/spr_def.h> + +#ifdef __tilegx__ +#define bnzt bnezt +#endif + +STD_ENTRY(current_text_addr) + { move r0, lr; jrp lr } + STD_ENDPROC(current_text_addr) + +STD_ENTRY(dump_stack) + { move r2, lr; lnk r1 } + { move r4, r52; addli r1, r1, dump_stack - . } + { move r3, sp; j _dump_stack } + jrp lr /* keep backtracer happy */ + STD_ENDPROC(dump_stack) + +STD_ENTRY(KBacktraceIterator_init_current) + { move r2, lr; lnk r1 } + { move r4, r52; addli r1, r1, KBacktraceIterator_init_current - . } + { move r3, sp; j _KBacktraceIterator_init_current } + jrp lr /* keep backtracer happy */ + STD_ENDPROC(KBacktraceIterator_init_current) + +/* Loop forever on a nap during SMP boot. */ +STD_ENTRY(smp_nap) + nap + nop /* avoid provoking the icache prefetch with a jump */ + j smp_nap /* we are not architecturally guaranteed not to exit nap */ + jrp lr /* clue in the backtracer */ + STD_ENDPROC(smp_nap) + +/* + * Enable interrupts racelessly and then nap until interrupted. + * Architecturally, we are guaranteed that enabling interrupts via + * mtspr to INTERRUPT_CRITICAL_SECTION only interrupts at the next PC. + * This function's _cpu_idle_nap address is special; see intvec.S. + * When interrupted at _cpu_idle_nap, we bump the PC forward 8, and + * as a result return to the function that called _cpu_idle(). + */ +STD_ENTRY(_cpu_idle) + movei r1, 1 + IRQ_ENABLE_LOAD(r2, r3) + mtspr INTERRUPT_CRITICAL_SECTION, r1 + IRQ_ENABLE_APPLY(r2, r3) /* unmask, but still with ICS set */ + mtspr INTERRUPT_CRITICAL_SECTION, zero + .global _cpu_idle_nap +_cpu_idle_nap: + nap + nop /* avoid provoking the icache prefetch with a jump */ + jrp lr + STD_ENDPROC(_cpu_idle) |