On Tue, Jan 10, 2023 at 12:52:48AM +0800, Jia Jie Ho wrote:
>
> +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);
> + /* SEU occurred, reseeding required*/
> + writel(STARFIVE_CTRL_EXEC_RANDRESEED, trng->base + STARFIVE_CTRL);
This could occur at the same time as a GENE_RANDNUM write so perhaps
you should add some locking?
> + ret = devm_request_irq(&pdev->dev, irq, starfive_trng_irq, 0, pdev->name,
> + (void *)trng);
> + if (ret)
> + return dev_err_probe(&pdev->dev, irq,
> + "Failed to register interrupt handler\n");
...
> + init_completion(&trng->random_done);
> + init_completion(&trng->reseed_done);
These completion initialisations should be moved above the IRQ
registration because you should always be prepared to get spurious
interrupts.
Otherwise the patch looks good.
Thanks,
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
