Messages in this thread | | | Date | Tue, 10 Jan 2023 15:40:49 +0800 | From | Herbert Xu <> | Subject | Re: [PATCH v3 2/3] hwrng: starfive - Add TRNG driver for StarFive SoC |
| |
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@gondor.apana.org.au> Home Page: http://gondor.apana.org.au/~herbert/ PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt
| |