mirror of https://gitee.com/openkylin/linux.git
68 lines
1.3 KiB
C
68 lines
1.3 KiB
C
|
/* SPDX-License-Identifier: GPL-2.0 */
|
||
|
|
#ifndef _ASM_ARCHRANDOM_H
|
||
|
|
#define _ASM_ARCHRANDOM_H
|
||
|
|
|
||
|
|
#ifdef CONFIG_ARCH_RANDOM
|
||
|
|
|
||
|
|
#include <linux/random.h>
|
||
|
|
#include <asm/cpufeature.h>
|
||
|
|
|
||
|
|
static inline bool __arm64_rndr(unsigned long *v)
|
||
|
|
{
|
||
|
|
bool ok;
|
||
|
|
|
||
|
|
/*
|
||
|
|
* Reads of RNDR set PSTATE.NZCV to 0b0000 on success,
|
||
|
|
* and set PSTATE.NZCV to 0b0100 otherwise.
|
||
|
|
*/
|
||
|
|
asm volatile(
|
||
|
|
__mrs_s("%0", SYS_RNDR_EL0) "\n"
|
||
|
|
" cset %w1, ne\n"
|
||
|
|
: "=r" (*v), "=r" (ok)
|
||
|
|
:
|
||
|
|
: "cc");
|
||
|
|
|
||
|
|
return ok;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline bool __must_check arch_get_random_long(unsigned long *v)
|
||
|
|
{
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline bool __must_check arch_get_random_int(unsigned int *v)
|
||
|
|
{
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
|
||
|
|
{
|
||
|
|
/*
|
||
|
|
* Only support the generic interface after we have detected
|
||
|
|
* the system wide capability, avoiding complexity with the
|
||
|
|
* cpufeature code and with potential scheduling between CPUs
|
||
|
|
* with and without the feature.
|
||
|
|
*/
|
||
|
|
if (!cpus_have_const_cap(ARM64_HAS_RNG))
|
||
|
|
return false;
|
||
|
|
|
||
|
|
return __arm64_rndr(v);
|
||
|
|
}
|
||
|
|
|
||
|
|
|
||
|
|
static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
|
||
|
|
{
|
||
|
|
unsigned long val;
|
||
|
|
bool ok = arch_get_random_seed_long(&val);
|
||
|
|
|
||
|
|
*v = val;
|
||
|
|
return ok;
|
||
|
|
}
|
||
|
|
|
||
|
|
#else
|
||
|
|
|
||
|
|
static inline bool __arm64_rndr(unsigned long *v) { return false; }
|
||
|
|
|
||
|
|
#endif /* CONFIG_ARCH_RANDOM */
|
||
|
|
#endif /* _ASM_ARCHRANDOM_H */
|