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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 __ASSEMBLER__
6
7#include <linux/bug.h>
8#include <asm/cputable.h>
9
10static __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
21extern struct static_key_true cpu_feature_keys[NUM_CPU_FTR_KEYS];
22
23static __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
48static __always_inline bool cpu_has_feature(unsigned long feature)
49{
50 return early_cpu_has_feature(feature);
51}
52#endif
53
54#endif /* __ASSEMBLER__ */
55#endif /* __ASM_POWERPC_CPU_HAS_FEATURE_H */