linux_dsm_epyc7002/arch/x86/include/asm/archrandom.h
Thomas Gleixner a61127c213 treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 335
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms and conditions of the gnu general public license
  version 2 as published by the free software foundation this program
  is distributed in the hope it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not write to the free
  software foundation inc 51 franklin st fifth floor boston ma 02110
  1301 usa

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 111 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190530000436.567572064@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-05 17:37:06 +02:00

116 lines
2.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0-only */
/*
* This file is part of the Linux kernel.
*
* Copyright (c) 2011-2014, Intel Corporation
* Authors: Fenghua Yu <fenghua.yu@intel.com>,
* H. Peter Anvin <hpa@linux.intel.com>
*/
#ifndef ASM_X86_ARCHRANDOM_H
#define ASM_X86_ARCHRANDOM_H
#include <asm/processor.h>
#include <asm/cpufeature.h>
#define RDRAND_RETRY_LOOPS 10
#define RDRAND_INT ".byte 0x0f,0xc7,0xf0"
#define RDSEED_INT ".byte 0x0f,0xc7,0xf8"
#ifdef CONFIG_X86_64
# define RDRAND_LONG ".byte 0x48,0x0f,0xc7,0xf0"
# define RDSEED_LONG ".byte 0x48,0x0f,0xc7,0xf8"
#else
# define RDRAND_LONG RDRAND_INT
# define RDSEED_LONG RDSEED_INT
#endif
/* Unconditional execution of RDRAND and RDSEED */
static inline bool rdrand_long(unsigned long *v)
{
bool ok;
unsigned int retry = RDRAND_RETRY_LOOPS;
do {
asm volatile(RDRAND_LONG
CC_SET(c)
: CC_OUT(c) (ok), "=a" (*v));
if (ok)
return true;
} while (--retry);
return false;
}
static inline bool rdrand_int(unsigned int *v)
{
bool ok;
unsigned int retry = RDRAND_RETRY_LOOPS;
do {
asm volatile(RDRAND_INT
CC_SET(c)
: CC_OUT(c) (ok), "=a" (*v));
if (ok)
return true;
} while (--retry);
return false;
}
static inline bool rdseed_long(unsigned long *v)
{
bool ok;
asm volatile(RDSEED_LONG
CC_SET(c)
: CC_OUT(c) (ok), "=a" (*v));
return ok;
}
static inline bool rdseed_int(unsigned int *v)
{
bool ok;
asm volatile(RDSEED_INT
CC_SET(c)
: CC_OUT(c) (ok), "=a" (*v));
return ok;
}
/* Conditional execution based on CPU type */
#define arch_has_random() static_cpu_has(X86_FEATURE_RDRAND)
#define arch_has_random_seed() static_cpu_has(X86_FEATURE_RDSEED)
/*
* These are the generic interfaces; they must not be declared if the
* stubs in <linux/random.h> are to be invoked,
* i.e. CONFIG_ARCH_RANDOM is not defined.
*/
#ifdef CONFIG_ARCH_RANDOM
static inline bool arch_get_random_long(unsigned long *v)
{
return arch_has_random() ? rdrand_long(v) : false;
}
static inline bool arch_get_random_int(unsigned int *v)
{
return arch_has_random() ? rdrand_int(v) : false;
}
static inline bool arch_get_random_seed_long(unsigned long *v)
{
return arch_has_random_seed() ? rdseed_long(v) : false;
}
static inline bool arch_get_random_seed_int(unsigned int *v)
{
return arch_has_random_seed() ? rdseed_int(v) : false;
}
extern void x86_init_rdrand(struct cpuinfo_x86 *c);
#else /* !CONFIG_ARCH_RANDOM */
static inline void x86_init_rdrand(struct cpuinfo_x86 *c) { }
#endif /* !CONFIG_ARCH_RANDOM */
#endif /* ASM_X86_ARCHRANDOM_H */