33 lines
876 B
C
33 lines
876 B
C
/*
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* s390 arch random implementation.
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*
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* Copyright IBM Corp. 2017
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* Author(s): Harald Freudenberger <freude@de.ibm.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License (version 2 only)
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* as published by the Free Software Foundation.
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*
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*/
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#include <linux/kernel.h>
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#include <linux/atomic.h>
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#include <linux/random.h>
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#include <linux/static_key.h>
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#include <asm/cpacf.h>
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DEFINE_STATIC_KEY_FALSE(s390_arch_random_available);
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atomic64_t s390_arch_random_counter = ATOMIC64_INIT(0);
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EXPORT_SYMBOL(s390_arch_random_counter);
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static int __init s390_arch_random_init(void)
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{
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/* check if subfunction CPACF_PRNO_TRNG is available */
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if (cpacf_query_func(CPACF_PRNO, CPACF_PRNO_TRNG))
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static_branch_enable(&s390_arch_random_available);
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return 0;
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}
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arch_initcall(s390_arch_random_init);
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