summaryrefslogtreecommitdiff
path: root/include/crypto/internal/rng.h
blob: a52ef3483dd75032134c2d2b0785f76520e2cceb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
/*
 * RNG: Random Number Generator  algorithms under the crypto API
 *
 * Copyright (c) 2008 Neil Horman <nhorman@tuxdriver.com>
 * Copyright (c) 2015 Herbert Xu <herbert@gondor.apana.org.au>
 *
 * This program is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation; either version 2 of the License, or (at your option)
 * any later version.
 *
 */

#ifndef _CRYPTO_INTERNAL_RNG_H
#define _CRYPTO_INTERNAL_RNG_H

#include <crypto/algapi.h>
#include <crypto/rng.h>

int crypto_register_rng(struct rng_alg *alg);
void crypto_unregister_rng(struct rng_alg *alg);
int crypto_register_rngs(struct rng_alg *algs, int count);
void crypto_unregister_rngs(struct rng_alg *algs, int count);

#if defined(CONFIG_CRYPTO_RNG) || defined(CONFIG_CRYPTO_RNG_MODULE)
int crypto_del_default_rng(void);
#else
static inline int crypto_del_default_rng(void)
{
	return 0;
}
#endif

static inline void *crypto_rng_ctx(struct crypto_rng *tfm)
{
	return crypto_tfm_ctx(&tfm->base);
}

static inline void crypto_rng_set_entropy(struct crypto_rng *tfm,
					  const u8 *data, unsigned int len)
{
	crypto_rng_alg(tfm)->set_ent(tfm, data, len);
}

#endif
. It occurs because the platform BIOS may erroneously enable an energy-efficiency setting -- MSR_IA32_POWER_CTL BIT-EE, which is not recommended to be enabled on this SKU. On the failing systems, this BIOS issue was not discovered when the desktop motherboard was tested with Windows, because the BIOS also neglects to provide the ACPI/CPPC table, that Windows requires to enable HWP, and so Windows runs in legacy P-state mode, where this setting has no effect. Linux' intel_pstate driver does not require ACPI/CPPC to enable HWP, and so it runs in HWP mode, exposing this incorrect BIOS configuration. There are several ways to address this problem. First, Linux can also run in legacy P-state mode on this system. As intel_pstate is how Linux enables HWP, booting with "intel_pstate=disable" will run in acpi-cpufreq/ondemand legacy p-state mode. Or second, the "performance" governor can be used with intel_pstate, which will modify HWP.EPP to 0. Or third, starting in 4.10, the /sys/devices/system/cpu/cpufreq/policy*/energy_performance_preference attribute in can be updated from "balance_power" to "performance". Or fourth, apply this patch, which fixes the erroneous setting of MSR_IA32_POWER_CTL BIT_EE on this model, allowing the default configuration to function as designed. Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> Reviewed-by: Len Brown <len.brown@intel.com> Cc: 4.6+ <stable@vger.kernel.org> # 4.6+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Diffstat (limited to 'tools/lib/api/debug.c')