machine.h

  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 */