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	64fc74f5f6
	
	
	
		
			
			The -mfix-loongson2f-jump option provided by latest CVS binutils have fixed
the out-of-order issue of Loongson-2F described in chapter 15 of the
Loongson2F User Manual [1, 2], but introduced some problems.
The option changes all of the jump target to "addr & 0xcfffffff" through the
at($1) register, but for the reboot address of Loongson 2F 0xbfc00000 this is
wrong.  Avoids the problem via telling the assembler to not use the $at
register.
[1] Loongson2F User Manual (Chinese Version)
    http://www.loongson.cn/uploadfile/file/200808211
[2] English Version of Chapter 15:
    http://groups.google.com.hk/group/loongson-dev/msg/e0d2e220958f10a6?dmode=source
Reported-and-tested-by: Liu Shiwei <liushiwei@gmail.com>
Signed-off-by: Wu Zhangjin <wuzhangjin@gmail.com>
Cc: linux-mips <linux-mips@linux-mips.org>
Patchwork: http://patchwork.linux-mips.org/patch/1109/
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
		
	
			
		
			
				
	
	
		
			70 lines
		
	
	
	
		
			1.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			70 lines
		
	
	
	
		
			1.6 KiB
			
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This program is free software; you can redistribute  it and/or modify it
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|  * under  the terms of  the GNU General  Public License as published by the
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|  * Free Software Foundation;  either version 2 of the  License, or (at your
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|  * option) any later version.
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|  *
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|  * Copyright (C) 2007 Lemote, Inc. & Institute of Computing Technology
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|  * Author: Fuxin Zhang, zhangfx@lemote.com
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|  * Copyright (C) 2009 Lemote, Inc.
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|  * Author: Zhangjin Wu, wuzhangjin@gmail.com
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|  */
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| #include <linux/init.h>
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| #include <linux/pm.h>
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| 
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| #include <asm/reboot.h>
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| 
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| #include <loongson.h>
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| 
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| static inline void loongson_reboot(void)
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| {
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| #ifndef CONFIG_CPU_JUMP_WORKAROUNDS
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| 	((void (*)(void))ioremap_nocache(LOONGSON_BOOT_BASE, 4)) ();
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| #else
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| 	void (*func)(void);
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| 
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| 	func = (void *)ioremap_nocache(LOONGSON_BOOT_BASE, 4);
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| 
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| 	__asm__ __volatile__(
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| 	"       .set    noat                                            \n"
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| 	"       jr      %[func]                                         \n"
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| 	"       .set    at                                              \n"
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| 	: /* No outputs */
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| 	: [func] "r" (func));
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| #endif
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| }
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| 
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| static void loongson_restart(char *command)
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| {
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| 	/* do preparation for reboot */
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| 	mach_prepare_reboot();
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| 
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| 	/* reboot via jumping to boot base address */
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| 	loongson_reboot();
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| }
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| 
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| static void loongson_poweroff(void)
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| {
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| 	mach_prepare_shutdown();
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| 	unreachable();
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| }
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| 
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| static void loongson_halt(void)
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| {
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| 	pr_notice("\n\n** You can safely turn off the power now **\n\n");
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| 	while (1) {
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| 		if (cpu_wait)
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| 			cpu_wait();
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| 	}
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| }
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| 
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| static int __init mips_reboot_setup(void)
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| {
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| 	_machine_restart = loongson_restart;
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| 	_machine_halt = loongson_halt;
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| 	pm_power_off = loongson_poweroff;
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| 
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| 	return 0;
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| }
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| 
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| arch_initcall(mips_reboot_setup);
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