82 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			82 lines
		
	
	
		
			2.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * This file is subject to the terms and conditions of the GNU General Public
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|  * License.  See the file "COPYING" in the main directory of this archive
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|  * for more details.
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|  *
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|  * Copyright (C) 2005 Thiemo Seufer
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|  * Copyright (C) 2005  MIPS Technologies, Inc.  All rights reserved.
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|  *	Author: Maciej W. Rozycki <macro@mips.com>
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|  */
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| 
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| #include <linux/init.h>
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| 
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| #include <asm/addrspace.h>
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| #include <asm/bug.h>
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| #include <asm/cacheflush.h>
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| 
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| #ifndef CKSEG2
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| #define CKSEG2 CKSSEG
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| #endif
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| #ifndef TO_PHYS_MASK
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| #define TO_PHYS_MASK -1
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| #endif
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| 
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| /*
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|  * FUNC is executed in one of the uncached segments, depending on its
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|  * original address as follows:
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|  *
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|  * 1. If the original address is in CKSEG0 or CKSEG1, then the uncached
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|  *    segment used is CKSEG1.
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|  * 2. If the original address is in XKPHYS, then the uncached segment
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|  *    used is XKPHYS(2).
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|  * 3. Otherwise it's a bug.
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|  *
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|  * The same remapping is done with the stack pointer.  Stack handling
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|  * works because we don't handle stack arguments or more complex return
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|  * values, so we can avoid sharing the same stack area between a cached
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|  * and the uncached mode.
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|  */
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| unsigned long __cpuinit run_uncached(void *func)
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| {
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| 	register long sp __asm__("$sp");
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| 	register long ret __asm__("$2");
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| 	long lfunc = (long)func, ufunc;
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| 	long usp;
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| 
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| 	if (sp >= (long)CKSEG0 && sp < (long)CKSEG2)
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| 		usp = CKSEG1ADDR(sp);
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| #ifdef CONFIG_64BIT
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| 	else if ((long long)sp >= (long long)PHYS_TO_XKPHYS(0, 0) &&
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| 		 (long long)sp < (long long)PHYS_TO_XKPHYS(8, 0))
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| 		usp = PHYS_TO_XKPHYS(K_CALG_UNCACHED,
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| 				     XKPHYS_TO_PHYS((long long)sp));
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| #endif
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| 	else {
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| 		BUG();
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| 		usp = sp;
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| 	}
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| 	if (lfunc >= (long)CKSEG0 && lfunc < (long)CKSEG2)
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| 		ufunc = CKSEG1ADDR(lfunc);
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| #ifdef CONFIG_64BIT
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| 	else if ((long long)lfunc >= (long long)PHYS_TO_XKPHYS(0, 0) &&
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| 		 (long long)lfunc < (long long)PHYS_TO_XKPHYS(8, 0))
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| 		ufunc = PHYS_TO_XKPHYS(K_CALG_UNCACHED,
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| 				       XKPHYS_TO_PHYS((long long)lfunc));
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| #endif
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| 	else {
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| 		BUG();
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| 		ufunc = lfunc;
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| 	}
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| 
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| 	__asm__ __volatile__ (
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| 		"	move	$16, $sp\n"
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| 		"	move	$sp, %1\n"
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| 		"	jalr	%2\n"
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| 		"	move	$sp, $16"
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| 		: "=r" (ret)
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| 		: "r" (usp), "r" (ufunc)
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| 		: "$16", "$31");
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| 
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| 	return ret;
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| }
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