Linux kernel mirror (for testing)
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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Copyright IBM Corp. 1999, 2009
4 *
5 * Author(s): Martin Schwidefsky <schwidefsky@de.ibm.com>
6 */
7
8#ifndef __ASM_FACILITY_H
9#define __ASM_FACILITY_H
10
11#include <asm/facility-defs.h>
12#include <linux/string.h>
13#include <linux/preempt.h>
14#include <asm/lowcore.h>
15
16#define MAX_FACILITY_BIT (sizeof(((struct lowcore *)0)->stfle_fac_list) * 8)
17
18static inline void __set_facility(unsigned long nr, void *facilities)
19{
20 unsigned char *ptr = (unsigned char *) facilities;
21
22 if (nr >= MAX_FACILITY_BIT)
23 return;
24 ptr[nr >> 3] |= 0x80 >> (nr & 7);
25}
26
27static inline void __clear_facility(unsigned long nr, void *facilities)
28{
29 unsigned char *ptr = (unsigned char *) facilities;
30
31 if (nr >= MAX_FACILITY_BIT)
32 return;
33 ptr[nr >> 3] &= ~(0x80 >> (nr & 7));
34}
35
36static inline int __test_facility(unsigned long nr, void *facilities)
37{
38 unsigned char *ptr;
39
40 if (nr >= MAX_FACILITY_BIT)
41 return 0;
42 ptr = (unsigned char *) facilities + (nr >> 3);
43 return (*ptr & (0x80 >> (nr & 7))) != 0;
44}
45
46/*
47 * The test_facility function uses the bit odering where the MSB is bit 0.
48 * That makes it easier to query facility bits with the bit number as
49 * documented in the Principles of Operation.
50 */
51static inline int test_facility(unsigned long nr)
52{
53 unsigned long facilities_als[] = { FACILITIES_ALS };
54
55 if (__builtin_constant_p(nr) && nr < sizeof(facilities_als) * 8) {
56 if (__test_facility(nr, &facilities_als))
57 return 1;
58 }
59 return __test_facility(nr, &S390_lowcore.stfle_fac_list);
60}
61
62/**
63 * stfle - Store facility list extended
64 * @stfle_fac_list: array where facility list can be stored
65 * @size: size of passed in array in double words
66 */
67static inline void __stfle(u64 *stfle_fac_list, int size)
68{
69 unsigned long nr;
70
71 asm volatile(
72 " stfl 0(0)\n"
73 : "=m" (S390_lowcore.stfl_fac_list));
74 nr = 4; /* bytes stored by stfl */
75 memcpy(stfle_fac_list, &S390_lowcore.stfl_fac_list, 4);
76 if (S390_lowcore.stfl_fac_list & 0x01000000) {
77 /* More facility bits available with stfle */
78 register unsigned long reg0 asm("0") = size - 1;
79
80 asm volatile(".insn s,0xb2b00000,0(%1)" /* stfle */
81 : "+d" (reg0)
82 : "a" (stfle_fac_list)
83 : "memory", "cc");
84 nr = (reg0 + 1) * 8; /* # bytes stored by stfle */
85 }
86 memset((char *) stfle_fac_list + nr, 0, size * 8 - nr);
87}
88
89static inline void stfle(u64 *stfle_fac_list, int size)
90{
91 preempt_disable();
92 __stfle(stfle_fac_list, size);
93 preempt_enable();
94}
95
96#endif /* __ASM_FACILITY_H */