59 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			59 lines
		
	
	
		
			1.7 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* SPDX-License-Identifier: GPL-2.0-only */
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| /*
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|  * Copyright (C) 2014 Linaro Ltd. <ard.biesheuvel@linaro.org>
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|  */
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| 
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| #ifndef __LINUX_CPUFEATURE_H
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| #define __LINUX_CPUFEATURE_H
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| 
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| #ifdef CONFIG_GENERIC_CPU_AUTOPROBE
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| 
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| #include <linux/init.h>
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| #include <linux/mod_devicetable.h>
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| #include <asm/cpufeature.h>
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| 
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| /*
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|  * Macros imported from <asm/cpufeature.h>:
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|  * - cpu_feature(x)		ordinal value of feature called 'x'
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|  * - cpu_have_feature(u32 n)	whether feature #n is available
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|  * - MAX_CPU_FEATURES		upper bound for feature ordinal values
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|  * Optional:
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|  * - CPU_FEATURE_TYPEFMT	format string fragment for printing the cpu type
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|  * - CPU_FEATURE_TYPEVAL	set of values matching the format string above
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|  */
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| 
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| #ifndef CPU_FEATURE_TYPEFMT
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| #define CPU_FEATURE_TYPEFMT	"%s"
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| #endif
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| 
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| #ifndef CPU_FEATURE_TYPEVAL
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| #define CPU_FEATURE_TYPEVAL	ELF_PLATFORM
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| #endif
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| 
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| /*
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|  * Use module_cpu_feature_match(feature, module_init_function) to
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|  * declare that
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|  * a) the module shall be probed upon discovery of CPU feature 'feature'
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|  *    (typically at boot time using udev)
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|  * b) the module must not be loaded if CPU feature 'feature' is not present
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|  *    (not even by manual insmod).
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|  *
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|  * For a list of legal values for 'feature', please consult the file
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|  * 'asm/cpufeature.h' of your favorite architecture.
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|  */
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| #define module_cpu_feature_match(x, __initfunc)			\
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| static struct cpu_feature const __maybe_unused cpu_feature_match_ ## x[] = \
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| 	{ { .feature = cpu_feature(x) }, { } };			\
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| MODULE_DEVICE_TABLE(cpu, cpu_feature_match_ ## x);		\
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| 								\
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| static int __init cpu_feature_match_ ## x ## _init(void)	\
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| {								\
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| 	if (!cpu_have_feature(cpu_feature(x)))			\
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| 		return -ENODEV;					\
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| 	return __initfunc();					\
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| }								\
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| module_init(cpu_feature_match_ ## x ## _init)
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| 
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| #endif
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| #endif
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