Book a Demo!
CoCalc Logo Icon
StoreFeaturesDocsShareSupportNewsAboutPoliciesSign UpSign In
torvalds
GitHub Repository: torvalds/linux
 Path: blob/master/arch/powerpc/include/asm/cpu_has_feature.h
26481 views
1
/* SPDX-License-Identifier: GPL-2.0 */

2
#ifndef __ASM_POWERPC_CPU_HAS_FEATURE_H

3
#define __ASM_POWERPC_CPU_HAS_FEATURE_H

4


5
#ifndef __ASSEMBLY__

6


7
#include <linux/bug.h>

8
#include <asm/cputable.h>

9


10
static __always_inline bool early_cpu_has_feature(unsigned long feature)

11
{

12
	return !!((CPU_FTRS_ALWAYS & feature) ||

13
		  (CPU_FTRS_POSSIBLE & cur_cpu_spec->cpu_features & feature));

14
}

15


16
#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECKS

17
#include <linux/jump_label.h>

18


19
#define NUM_CPU_FTR_KEYS	BITS_PER_LONG

20


21
extern struct static_key_true cpu_feature_keys[NUM_CPU_FTR_KEYS];

22


23
static __always_inline bool cpu_has_feature(unsigned long feature)

24
{

25
	int i;

26


27
	BUILD_BUG_ON(!__builtin_constant_p(feature));

28
	BUILD_BUG_ON(__builtin_popcountl(feature) > 1);

29


30
#ifdef CONFIG_JUMP_LABEL_FEATURE_CHECK_DEBUG

31
	if (!static_key_feature_checks_initialized) {

32
		printk("Warning! cpu_has_feature() used prior to jump label init!\n");

33
		dump_stack();

34
		return early_cpu_has_feature(feature);

35
	}

36
#endif

37


38
	if (CPU_FTRS_ALWAYS & feature)

39
		return true;

40


41
	if (!(CPU_FTRS_POSSIBLE & feature))

42
		return false;

43


44
	i = __builtin_ctzl(feature);

45
	return static_branch_likely(&cpu_feature_keys[i]);

46
}

47
#else

48
static __always_inline bool cpu_has_feature(unsigned long feature)

49
{

50
	return early_cpu_has_feature(feature);

51
}

52
#endif

53


54
#endif /* __ASSEMBLY__ */

55
#endif /* __ASM_POWERPC_CPU_HAS_FEATURE_H */

56


57