/* * 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) /* * Implement execve().  The i386 code has a note that forking from kernel * space results in no copy on write until the execve, so we should be * careful not to write to the stack here. */STD_ENTRY(kernel_execve)	moveli TREG_SYSCALL_NR_NAME, __NR_execve	swint1	jrp lr	STD_ENDPROC(kernel_execve) /* * We don't run this function directly, but instead copy it to a page * we map into every user process.  See vdso_setup(). * * Note that libc has a copy of this function that it uses to compare * against the PC when a stack backtrace ends, so if this code is * changed, the libc implementation(s) should also be updated. */	.pushsection .dataENTRY(__rt_sigreturn)	moveli TREG_SYSCALL_NR_NAME,__NR_rt_sigreturn	swint1	ENDPROC(__rt_sigreturn)	ENTRY(__rt_sigreturn_end)	.popsection 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) /* * Reset our stack to r1/r2 (sp and ksp0+cpu respectively), then * free the old stack (passed in r0) and re-invoke cpu_idle(). * We update sp and ksp0 simultaneously to avoid backtracer warnings. */STD_ENTRY(cpu_idle_on_new_stack)	{	 move sp, r1	 mtspr SPR_SYSTEM_SAVE_K_0, r2	}	jal free_thread_info	j cpu_idle	STD_ENDPROC(cpu_idle_on_new_stack) /* 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	mtspr INTERRUPT_CRITICAL_SECTION, r1	IRQ_ENABLE(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)