Some hardware platforms, the TS-7800[1] is one for example, can
supply the kernel with an entropy source, albeit a slow one for
TS-7800 users, by just reading a particular IO address. This
source must not be read above a certain rate otherwise the quality
suffers.
The driver is then hooked into by calling
platform_device_(register|add|del) passing a structure similar to:
------
static struct timeriomem_rng_data ts78xx_ts_rng_data = {
.address = (u32 *__iomem) TS_RNG,
.period = 1000000, /* one second */
};
static struct platform_device ts78xx_ts_rng_device = {
.name = "timeriomem_rng",
.id = -1,
.dev = {
.platform_data = &ts78xx_ts_rng_data,
},
.num_resources = 0,
};
------
[1] http://www.embeddedarm.com/products/board-detail.php?product=TS-7800
Signed-off-by: Alexander Clouter <alex@digriz.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Note that by itself, having a "hardware" random generator does very
little: you should probably run "rngd" in your guest to feed this into
the kernel entropy pool.
Included:
virtio_rng: dont use vmalloced addresses for virtio
If virtio_rng is build as a module, random_data is an address
in vmalloc space. As virtio expects guest real addresses, this
can cause any kind of funny behaviour, so lets allocate
random_data dynamically with kmalloc.
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Driver for the on-chip hardware random number generator on PA Semi
PA6T-1682M.
Signed-off-by: Egor Martovetsky <egor@pasemi.com>
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Michael Buesch <mb@bu3sch.de>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Kumar Gala <galak@gate.crashing.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Despite it being small, there should be the option of making it a
module...
Signed-off-by: Jan Beulich <jbeulich@novell.com>
Cc: Michael Buesch <mb@bu3sch.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
