linux/arch/powerpc/platforms/pseries/rng.c

46 lines
994 B
C

/*
* Copyright 2013, Michael Ellerman, IBM Corporation.
*
* 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.
*/
#define pr_fmt(fmt) "pseries-rng: " fmt
#include <linux/kernel.h>
#include <linux/of.h>
#include <asm/archrandom.h>
#include <asm/machdep.h>
#include <asm/plpar_wrappers.h>
static int pseries_get_random_long(unsigned long *v)
{
unsigned long retbuf[PLPAR_HCALL_BUFSIZE];
if (plpar_hcall(H_RANDOM, retbuf) == H_SUCCESS) {
*v = retbuf[0];
return 1;
}
return 0;
}
static __init int rng_init(void)
{
struct device_node *dn;
dn = of_find_compatible_node(NULL, NULL, "ibm,random");
if (!dn)
return -ENODEV;
pr_info("Registering arch random hook.\n");
ppc_md.get_random_long = pseries_get_random_long;
return 0;
}
machine_subsys_initcall(pseries, rng_init);