On Mon, Dec 11, 2017 at 3:06 PM, Łukasz Stelmach <l.stelmach@xxxxxxxxxxx> wrote: > Cc: Marek Szyprowski <m.szyprowski@xxxxxxxxxxx>, Bartlomiej Zolnierkiewicz <b.zolnierkie@xxxxxxxxxxx> > > Add support for PRNG in Exynos5250+ SoCs. > > Signed-off-by: Łukasz Stelmach <l.stelmach@xxxxxxxxxxx> > --- > .../bindings/crypto/samsung,exynos-rng4.txt | 4 ++- > drivers/crypto/exynos-rng.c | 32 ++++++++++++++++++++-- > 2 files changed, 33 insertions(+), 3 deletions(-) > > diff --git a/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt b/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt > index 4ca8dd4d7e66..a13fbdb4bd88 100644 > --- a/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt > +++ b/Documentation/devicetree/bindings/crypto/samsung,exynos-rng4.txt > @@ -2,7 +2,9 @@ Exynos Pseudo Random Number Generator > > Required properties: > > -- compatible : Should be "samsung,exynos4-rng". > +- compatible : One of: > + - "samsung,exynos4-rng" for Exynos4210 and Exynos4412 > + - "samsung,exynos5250-prng" for Exynos5250+ > - reg : Specifies base physical address and size of the registers map. > - clocks : Phandle to clock-controller plus clock-specifier pair. > - clock-names : "secss" as a clock name. > diff --git a/drivers/crypto/exynos-rng.c b/drivers/crypto/exynos-rng.c > index ed6ba796ad71..2f554b82f49f 100644 > --- a/drivers/crypto/exynos-rng.c > +++ b/drivers/crypto/exynos-rng.c > @@ -22,12 +22,17 @@ > #include <linux/err.h> > #include <linux/io.h> > #include <linux/module.h> > +#include <linux/of_device.h> > #include <linux/platform_device.h> > > #include <crypto/internal/rng.h> > > #define EXYNOS_RNG_CONTROL 0x0 > #define EXYNOS_RNG_STATUS 0x10 > + > +#define EXYNOS_RNG_SEED_CONF 0x14 > +#define EXYNOS_RNG_GEN_PRNG BIT(1) > + > #define EXYNOS_RNG_SEED_BASE 0x140 > #define EXYNOS_RNG_SEED(n) (EXYNOS_RNG_SEED_BASE + (n * 0x4)) > #define EXYNOS_RNG_OUT_BASE 0x160 > @@ -43,6 +48,12 @@ > #define EXYNOS_RNG_SEED_REGS 5 > #define EXYNOS_RNG_SEED_SIZE (EXYNOS_RNG_SEED_REGS * 4) > > +enum exynos_prng_type { > + EXYNOS_PRNG_UNKNOWN = 0, > + EXYNOS_PRNG_EXYNOS4, > + EXYNOS_PRNG_EXYNOS5, > +}; > + > /* > * Driver re-seeds itself with generated random numbers to increase > * the randomness. > @@ -63,6 +74,7 @@ struct exynos_rng_ctx { > /* Device associated memory */ > struct exynos_rng_dev { > struct device *dev; > + enum exynos_prng_type type; > void __iomem *mem; > struct clk *clk; > /* Generated numbers stored for seeding during resume */ > @@ -160,8 +172,13 @@ static int exynos_rng_get_random(struct exynos_rng_dev *rng, > { > int retry = EXYNOS_RNG_WAIT_RETRIES; > > - exynos_rng_writel(rng, EXYNOS_RNG_CONTROL_START, > - EXYNOS_RNG_CONTROL); > + if (rng->type == EXYNOS_PRNG_EXYNOS4) { > + exynos_rng_writel(rng, EXYNOS_RNG_CONTROL_START, > + EXYNOS_RNG_CONTROL); > + } else if (rng->type == EXYNOS_PRNG_EXYNOS5) { > + exynos_rng_writel(rng, EXYNOS_RNG_GEN_PRNG, > + EXYNOS_RNG_SEED_CONF); > + } > > while (!(exynos_rng_readl(rng, > EXYNOS_RNG_STATUS) & EXYNOS_RNG_STATUS_RNG_DONE) && --retry) > @@ -279,6 +296,13 @@ static int exynos_rng_probe(struct platform_device *pdev) > if (!rng) > return -ENOMEM; > > + rng->type = (enum exynos_prng_type)of_device_get_match_data(&pdev->dev); > + if (rng->type != EXYNOS_PRNG_EXYNOS4 && > + rng->type != EXYNOS_PRNG_EXYNOS5) { > + dev_err(&pdev->dev, "Unsupported PRNG type: %d", rng->type); > + return -ENOTSUPP; > + } > + This cannot happen. Device will be matched only on matching compatible thus rng->type will be always correct. Best regards, Krzysztof