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-rw-r--r--kernel/arch/tile/kernel/entry.S71
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diff --git a/kernel/arch/tile/kernel/entry.S b/kernel/arch/tile/kernel/entry.S
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+/*
+ * 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)