On Tue, Jun 20, 2017 at 11:59:47AM +0200, Maxime Ripard wrote:
> Hi,
>
> On Tue, Jun 20, 2017 at 10:58:19AM +0200, Corentin Labbe wrote:
> > The Security System have a PRNG, this patch add support for it via
> > crypto_rng.
>
> This might be a dumb question, but is the CRYPTO_RNG code really
> supposed to be used with PRNG?
>
Yes, see recently added drivers/crypto/exynos-rng.c
[...]
> > --- a/drivers/crypto/sunxi-ss/sun4i-ss.h
> > +++ b/drivers/crypto/sunxi-ss/sun4i-ss.h
> > @@ -32,6 +32,7 @@
> > #include <crypto/aes.h>
> > #include <crypto/des.h>
> > #include <crypto/internal/rng.h>
> > +#include <crypto/rng.h>
> >
> > #define SS_CTL 0x00
> > #define SS_KEY0 0x04
> > @@ -127,6 +128,9 @@
> > #define SS_RXFIFO_EMP_INT_ENABLE (1 << 2)
> > #define SS_TXFIFO_AVA_INT_ENABLE (1 << 0)
> >
> > +#define SS_SEED_LEN (192 / 8)
> > +#define SS_DATA_LEN (160 / 8)
> > +
> > struct sun4i_ss_ctx {
> > void __iomem *base;
> > int irq;
> > @@ -136,6 +140,7 @@ struct sun4i_ss_ctx {
> > struct device *dev;
> > struct resource *res;
> > spinlock_t slock; /* control the use of the device */
> > + u32 seed[SS_SEED_LEN / 4];
>
> Shouldn't you define SS_SEED_LEN in bits, and then use either
> BITS_PER_BYTE and BITS_PER_LONG so that it's obvious what you're doing
> ?
>
> And you could also make that variable defined based on the option,
> otherwise you'll always allocate that array, even if you're not using
> it.
I will do that
Thanks
