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
 13#include <linux/minmax.h>
 14#include <linux/string.h>
 15#include <linux/types.h>
 16#include <linux/preempt.h>
 17
 18#include <asm/lowcore.h>
 19
 20#define MAX_FACILITY_BIT (sizeof(stfle_fac_list) * 8)
 21
 22extern u64 stfle_fac_list[16];
 23extern u64 alt_stfle_fac_list[16];
 24
 25static inline void __set_facility(unsigned long nr, void *facilities)
 26{
 27	unsigned char *ptr = (unsigned char *) facilities;
 28
 29	if (nr >= MAX_FACILITY_BIT)
 30		return;
 31	ptr[nr >> 3] |= 0x80 >> (nr & 7);
 32}
 33
 34static inline void __clear_facility(unsigned long nr, void *facilities)
 35{
 36	unsigned char *ptr = (unsigned char *) facilities;
 37
 38	if (nr >= MAX_FACILITY_BIT)
 39		return;
 40	ptr[nr >> 3] &= ~(0x80 >> (nr & 7));
 41}
 42
 43static inline int __test_facility(unsigned long nr, void *facilities)
 44{
 45	unsigned char *ptr;
 46
 47	if (nr >= MAX_FACILITY_BIT)
 48		return 0;
 49	ptr = (unsigned char *) facilities + (nr >> 3);
 50	return (*ptr & (0x80 >> (nr & 7))) != 0;
 51}
 52
 53/*
 54 * The test_facility function uses the bit ordering where the MSB is bit 0.
 55 * That makes it easier to query facility bits with the bit number as
 56 * documented in the Principles of Operation.
 57 */
 58static inline int test_facility(unsigned long nr)
 59{
 60	unsigned long facilities_als[] = { FACILITIES_ALS };
 61
 62	if (__builtin_constant_p(nr) && nr < sizeof(facilities_als) * 8) {
 63		if (__test_facility(nr, &facilities_als))
 64			return 1;
 65	}
 66	return __test_facility(nr, &stfle_fac_list);
 67}
 68
 69static inline unsigned long __stfle_asm(u64 *stfle_fac_list, int size)
 70{
 71	unsigned long reg0 = size - 1;
 72
 73	asm volatile(
 74		"	lgr	0,%[reg0]\n"
 75		"	.insn	s,0xb2b00000,%[list]\n" /* stfle */
 76		"	lgr	%[reg0],0\n"
 77		: [reg0] "+&d" (reg0), [list] "+Q" (*stfle_fac_list)
 78		:
 79		: "memory", "cc", "0");
 80	return reg0;
 81}
 82
 83/**
 84 * stfle - Store facility list extended
 85 * @stfle_fac_list: array where facility list can be stored
 86 * @size: size of passed in array in double words
 87 */
 88static inline void __stfle(u64 *stfle_fac_list, int size)
 89{
 90	unsigned long nr;
 91	u32 stfl_fac_list;
 92
 93	asm volatile(
 94		"	stfl	0(0)\n"
 95		: "=m" (S390_lowcore.stfl_fac_list));
 96	stfl_fac_list = S390_lowcore.stfl_fac_list;
 97	memcpy(stfle_fac_list, &stfl_fac_list, 4);
 98	nr = 4; /* bytes stored by stfl */
 99	if (stfl_fac_list & 0x01000000) {
100		/* More facility bits available with stfle */
101		nr = __stfle_asm(stfle_fac_list, size);
102		nr = min_t(unsigned long, (nr + 1) * 8, size * 8);
103	}
104	memset((char *) stfle_fac_list + nr, 0, size * 8 - nr);
105}
106
107static inline void stfle(u64 *stfle_fac_list, int size)
108{
109	preempt_disable();
110	__stfle(stfle_fac_list, size);
111	preempt_enable();
112}
113
114#endif /* __ASM_FACILITY_H */