On Wed, Dec 28, 2022 at 03:11:02PM +0800, Jia Jie Ho wrote:
>
> +static int starfive_trng_cmd(struct starfive_trng *trng, u32 cmd)
> +{
> + int ret;
> +
> + ret = starfive_trng_wait_idle(trng);
> + if (ret)
> + return -ETIMEDOUT;
> +
> + switch (cmd) {
> + case STARFIVE_CTRL_EXEC_NOP:
> + writel(cmd, trng->base + STARFIVE_CTRL);
> + break;
> + case STARFIVE_CTRL_GENE_RANDNUM:
> + reinit_completion(&trng->random_done);
> + writel(cmd, trng->base + STARFIVE_CTRL);
> + ret = wait_for_completion_timeout(&trng->random_done, 3000);
Please don't use a constant jiffies value, because it may vary
in length. Instead use a constant millisecond value and convert
it to jiffies.
> +static irqreturn_t starfive_trng_irq(int irq, void *priv)
> +{
> + u32 status;
> + struct starfive_trng *trng = (struct starfive_trng *)priv;
> +
> + status = readl(trng->base + STARFIVE_ISTAT);
> + if (status & STARFIVE_ISTAT_RAND_RDY) {
> + writel(STARFIVE_ISTAT_RAND_RDY, trng->base + STARFIVE_ISTAT);
> + complete(&trng->random_done);
> + }
> +
> + if (status & STARFIVE_ISTAT_SEED_DONE) {
> + writel(STARFIVE_ISTAT_SEED_DONE, trng->base + STARFIVE_ISTAT);
> + complete(&trng->reseed_done);
> + }
> +
> + if (status & STARFIVE_ISTAT_LFSR_LOCKUP) {
> + writel(STARFIVE_ISTAT_LFSR_LOCKUP, trng->base + STARFIVE_ISTAT);
> + starfive_trng_cmd(trng, STARFIVE_CTRL_EXEC_RANDRESEED);
You should not sleep in an IRQ handler.
> +static int starfive_trng_read(struct hwrng *rng, void *buf, size_t max, bool wait)
You should respect the wait argument and not do polling/sleeping
if it is false.
Cheers,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
