| Message ID | 20171212163607.2985-3-l.stelmach@samsung.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Headers | show |
On Tue, Dec 12, 2017 at 5:36 PM, Łukasz Stelmach <l.stelmach@samsung.com> wrote: > Use memcpy_fromio() instead of custom exynos_rng_copy_random() function > to retrieve generated numbers from the registers of PRNG. If I recall correctly, you mentioned before that it improves the performance. If so it would be nice to mention some numbers here. Anyway it is fine with me: Reviewed-by: Krzysztof Kozlowski <krzk@kernel.org> Best regards, Krzysztof > > Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com> > --- > drivers/crypto/exynos-rng.c | 31 ++----------------------------- > 1 file changed, 2 insertions(+), 29 deletions(-) > > diff --git a/drivers/crypto/exynos-rng.c b/drivers/crypto/exynos-rng.c > index 825c09619eb8..dcdd444d0b3b 100644 > --- a/drivers/crypto/exynos-rng.c > +++ b/drivers/crypto/exynos-rng.c > @@ -131,34 +131,6 @@ static int exynos_rng_set_seed(struct exynos_rng_dev *rng, > } > > /* > - * Read from output registers and put the data under 'dst' array, > - * up to dlen bytes. > - * > - * Returns number of bytes actually stored in 'dst' (dlen > - * or EXYNOS_RNG_SEED_SIZE). > - */ > -static unsigned int exynos_rng_copy_random(struct exynos_rng_dev *rng, > - u8 *dst, unsigned int dlen) > -{ > - unsigned int cnt = 0; > - int i, j; > - u32 val; > - > - for (j = 0; j < EXYNOS_RNG_SEED_REGS; j++) { > - val = exynos_rng_readl(rng, EXYNOS_RNG_OUT(j)); > - > - for (i = 0; i < 4; i++) { > - dst[cnt] = val & 0xff; > - val >>= 8; > - if (++cnt >= dlen) > - return cnt; > - } > - } > - > - return cnt; > -} > - > -/* > * Start the engine and poll for finish. Then read from output registers > * filling the 'dst' buffer up to 'dlen' bytes or up to size of generated > * random data (EXYNOS_RNG_SEED_SIZE). > @@ -190,7 +162,8 @@ static int exynos_rng_get_random(struct exynos_rng_dev *rng, > /* Clear status bit */ > exynos_rng_writel(rng, EXYNOS_RNG_STATUS_RNG_DONE, > EXYNOS_RNG_STATUS); > - *read = exynos_rng_copy_random(rng, dst, dlen); > + *read = min_t(size_t, dlen, EXYNOS_RNG_SEED_SIZE); > + memcpy_fromio(dst, rng->mem + EXYNOS_RNG_OUT_BASE, *read); > > return 0; > } > -- > 2.11.0 > -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/drivers/crypto/exynos-rng.c b/drivers/crypto/exynos-rng.c index 825c09619eb8..dcdd444d0b3b 100644 --- a/drivers/crypto/exynos-rng.c +++ b/drivers/crypto/exynos-rng.c @@ -131,34 +131,6 @@ static int exynos_rng_set_seed(struct exynos_rng_dev *rng, } /* - * Read from output registers and put the data under 'dst' array, - * up to dlen bytes. - * - * Returns number of bytes actually stored in 'dst' (dlen - * or EXYNOS_RNG_SEED_SIZE). - */ -static unsigned int exynos_rng_copy_random(struct exynos_rng_dev *rng, - u8 *dst, unsigned int dlen) -{ - unsigned int cnt = 0; - int i, j; - u32 val; - - for (j = 0; j < EXYNOS_RNG_SEED_REGS; j++) { - val = exynos_rng_readl(rng, EXYNOS_RNG_OUT(j)); - - for (i = 0; i < 4; i++) { - dst[cnt] = val & 0xff; - val >>= 8; - if (++cnt >= dlen) - return cnt; - } - } - - return cnt; -} - -/* * Start the engine and poll for finish. Then read from output registers * filling the 'dst' buffer up to 'dlen' bytes or up to size of generated * random data (EXYNOS_RNG_SEED_SIZE). @@ -190,7 +162,8 @@ static int exynos_rng_get_random(struct exynos_rng_dev *rng, /* Clear status bit */ exynos_rng_writel(rng, EXYNOS_RNG_STATUS_RNG_DONE, EXYNOS_RNG_STATUS); - *read = exynos_rng_copy_random(rng, dst, dlen); + *read = min_t(size_t, dlen, EXYNOS_RNG_SEED_SIZE); + memcpy_fromio(dst, rng->mem + EXYNOS_RNG_OUT_BASE, *read); return 0; }
Use memcpy_fromio() instead of custom exynos_rng_copy_random() function to retrieve generated numbers from the registers of PRNG. Signed-off-by: Łukasz Stelmach <l.stelmach@samsung.com> --- drivers/crypto/exynos-rng.c | 31 ++----------------------------- 1 file changed, 2 insertions(+), 29 deletions(-)