lib/s390x/asm/facility.h

/* SPDX-License-Identifier: GPL-2.0-only */
/*
 * Copyright (c) 2017 Red Hat Inc
 *
 * Authors:
 *  David Hildenbrand <david@redhat.com>
 */
#ifndef _ASMS390X_FACILITY_H_
#define _ASMS390X_FACILITY_H_

#include <libcflat.h>
#include <asm/facility.h>
#include <asm/arch_def.h>
#include <bitops.h>
#include <sclp.h>

#define NB_STFL_DOUBLEWORDS 32
extern uint64_t stfl_doublewords[];

static inline bool test_facility(int nr)
{
	return test_bit_inv(nr, stfl_doublewords);
}

static inline void stfl(void)
{
	asm volatile("	stfl	0(0)\n" : : : "memory");
}

static inline unsigned int stfle(uint64_t *fac, unsigned int nb_doublewords)
{
	register unsigned long r0 asm("0") = nb_doublewords - 1;

	asm volatile("	.insn	s,0xb2b00000,0(%1)\n"
		     : "+d" (r0) : "a" (fac) : "memory", "cc");
	return r0 + 1;
}

static inline unsigned long stfle_size(void)
{
	uint64_t dummy;

	return stfle(&dummy, 1);
}

static inline void setup_facilities(void)
{
	stfl();
	memcpy(stfl_doublewords, &lowcore.stfl, sizeof(lowcore.stfl));
	if (test_facility(7))
		stfle(stfl_doublewords, NB_STFL_DOUBLEWORDS);
}

enum supp_on_prot_facility {
	SOP_NONE,
	SOP_BASIC,
	SOP_ENHANCED_1,
	SOP_ENHANCED_2,
};

static inline enum supp_on_prot_facility get_supp_on_prot_facility(void)
{
	if (sclp_facilities.has_esop) {
		if (test_facility(131)) /* side-effect-access facility */
			return SOP_ENHANCED_2;
		else
			return SOP_ENHANCED_1;
	}
	if (sclp_facilities.has_sop)
		return SOP_BASIC;
	return SOP_NONE;
}

#endif