[mirror_ubuntu-bionic-kernel.git] / arch / s390 / crypto / arch_random.c

// SPDX-License-Identifier: GPL-2.0
/*
 * s390 arch random implementation.
 *
 * Copyright IBM Corp. 2017
 * Author(s): Harald Freudenberger <freude@de.ibm.com>
 */

#include <linux/kernel.h>
#include <linux/atomic.h>
#include <linux/random.h>
#include <linux/static_key.h>
#include <asm/cpacf.h>

DEFINE_STATIC_KEY_FALSE(s390_arch_random_available);

atomic64_t s390_arch_random_counter = ATOMIC64_INIT(0);
EXPORT_SYMBOL(s390_arch_random_counter);

static int __init s390_arch_random_init(void)
{
	/* check if subfunction CPACF_PRNO_TRNG is available */
	if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
		static_branch_enable(&s390_arch_random_available);

	return 0;
}
arch_initcall(s390_arch_random_init);
Commit	Line	Data
20a884f5	1	// SPDX-License-Identifier: GPL-2.0
4c637cd8 HF	2	/*
	3	* s390 arch random implementation.
	4	*
	5	* Copyright IBM Corp. 2017
	6	* Author(s): Harald Freudenberger <freude@de.ibm.com>
4c637cd8 HF	7	*/
	8
	9	#include <linux/kernel.h>
	10	#include <linux/atomic.h>
92acfb74	11	#include <linux/random.h>
4c637cd8 HF	12	#include <linux/static_key.h>
	13	#include <asm/cpacf.h>
	14
	15	DEFINE_STATIC_KEY_FALSE(s390_arch_random_available);
	16
	17	atomic64_t s390_arch_random_counter = ATOMIC64_INIT(0);
	18	EXPORT_SYMBOL(s390_arch_random_counter);
	19
	20	static int __init s390_arch_random_init(void)
	21	{
	22	/* check if subfunction CPACF_PRNO_TRNG is available */
	23	if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
	24	static_branch_enable(&s390_arch_random_available);
	25
	26	return 0;
	27	}
	28	arch_initcall(s390_arch_random_init);