Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
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linux
1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright IBM Corp. 2024
4 */
5
6#ifndef __ASM_S390_MACHINE_H
7#define __ASM_S390_MACHINE_H
8
9#include <linux/const.h>
10
11#define MFEATURE_LOWCORE 0
12#define MFEATURE_PCI_MIO 1
13#define MFEATURE_SCC 2
14#define MFEATURE_TLB_GUEST 3
15#define MFEATURE_TX 4
16#define MFEATURE_ESOP 5
17#define MFEATURE_DIAG9C 6
18#define MFEATURE_VM 7
19#define MFEATURE_KVM 8
20#define MFEATURE_LPAR 9
21#define MFEATURE_DIAG288 10
22
23#ifndef __ASSEMBLER__
24
25#include <linux/bitops.h>
26#include <asm/alternative.h>
27
28extern unsigned long machine_features[1];
29
30#define MAX_MFEATURE_BIT (sizeof(machine_features) * BITS_PER_BYTE)
31
32static inline void __set_machine_feature(unsigned int nr, unsigned long *mfeatures)
33{
34 if (nr >= MAX_MFEATURE_BIT)
35 return;
36 __set_bit(nr, mfeatures);
37}
38
39static inline void set_machine_feature(unsigned int nr)
40{
41 __set_machine_feature(nr, machine_features);
42}
43
44static inline void __clear_machine_feature(unsigned int nr, unsigned long *mfeatures)
45{
46 if (nr >= MAX_MFEATURE_BIT)
47 return;
48 __clear_bit(nr, mfeatures);
49}
50
51static inline void clear_machine_feature(unsigned int nr)
52{
53 __clear_machine_feature(nr, machine_features);
54}
55
56static bool __test_machine_feature(unsigned int nr, unsigned long *mfeatures)
57{
58 if (nr >= MAX_MFEATURE_BIT)
59 return false;
60 return test_bit(nr, mfeatures);
61}
62
63static bool test_machine_feature(unsigned int nr)
64{
65 return __test_machine_feature(nr, machine_features);
66}
67
68static __always_inline bool __test_machine_feature_constant(unsigned int nr)
69{
70 asm goto(
71 ALTERNATIVE("brcl 15,%l[l_no]", "brcl 0,0", ALT_FEATURE(%[nr]))
72 :
73 : [nr] "i" (nr)
74 :
75 : l_no);
76 return true;
77l_no:
78 return false;
79}
80
81#define DEFINE_MACHINE_HAS_FEATURE(name, feature) \
82static __always_inline bool machine_has_##name(void) \
83{ \
84 if (!__is_defined(__DECOMPRESSOR) && __builtin_constant_p(feature)) \
85 return __test_machine_feature_constant(feature); \
86 return test_machine_feature(feature); \
87}
88
89DEFINE_MACHINE_HAS_FEATURE(relocated_lowcore, MFEATURE_LOWCORE)
90DEFINE_MACHINE_HAS_FEATURE(scc, MFEATURE_SCC)
91DEFINE_MACHINE_HAS_FEATURE(tlb_guest, MFEATURE_TLB_GUEST)
92DEFINE_MACHINE_HAS_FEATURE(tx, MFEATURE_TX)
93DEFINE_MACHINE_HAS_FEATURE(esop, MFEATURE_ESOP)
94DEFINE_MACHINE_HAS_FEATURE(diag9c, MFEATURE_DIAG9C)
95DEFINE_MACHINE_HAS_FEATURE(vm, MFEATURE_VM)
96DEFINE_MACHINE_HAS_FEATURE(kvm, MFEATURE_KVM)
97DEFINE_MACHINE_HAS_FEATURE(lpar, MFEATURE_LPAR)
98
99#define machine_is_vm machine_has_vm
100#define machine_is_kvm machine_has_kvm
101#define machine_is_lpar machine_has_lpar
102
103#endif /* __ASSEMBLER__ */
104#endif /* __ASM_S390_MACHINE_H */