Am Dienstag, 22. August 2023, 17:25:51 CEST schrieb Martin Kaiser: > Use polling to detect the end of the rngc self test. This is much simpler > than using an interrupt and a completion. > > Active waiting is no disadvantage here. The self test is run during > probe, there's nothing we could do in parallel at this time. If this driver is built-in you are stalling the boot process while polling, no? Unless probe_type = PROBE_PREFER_ASYNCHRONOUS is set of course. Best regards, Alexander > Signed-off-by: Martin Kaiser <martin@xxxxxxxxx> > --- > drivers/char/hw_random/imx-rngc.c | 15 +++++++-------- > 1 file changed, 7 insertions(+), 8 deletions(-) > > diff --git a/drivers/char/hw_random/imx-rngc.c > b/drivers/char/hw_random/imx-rngc.c index e4b385b01b11..85207535fd12 100644 > --- a/drivers/char/hw_random/imx-rngc.c > +++ b/drivers/char/hw_random/imx-rngc.c > @@ -17,6 +17,7 @@ > #include <linux/hw_random.h> > #include <linux/completion.h> > #include <linux/io.h> > +#include <linux/iopoll.h> > #include <linux/bitfield.h> > > #define RNGC_VER_ID 0x0000 > @@ -101,21 +102,19 @@ static inline void imx_rngc_irq_unmask(struct imx_rngc > *rngc) > > static int imx_rngc_self_test(struct imx_rngc *rngc) > { > - u32 cmd; > + u32 cmd, status; > int ret; > > - imx_rngc_irq_unmask(rngc); > - > /* run self test */ > cmd = readl(rngc->base + RNGC_COMMAND); > writel(cmd | RNGC_CMD_SELF_TEST, rngc->base + RNGC_COMMAND); > > - ret = wait_for_completion_timeout(&rngc->rng_op_done, > msecs_to_jiffies(RNGC_TIMEOUT)); - imx_rngc_irq_mask_clear(rngc); > - if (!ret) > - return -ETIMEDOUT; > + ret = readl_poll_timeout(rngc->base + RNGC_STATUS, status, > + status & RNGC_STATUS_ST_DONE, 1000, RNGC_TIMEOUT * 1000); > + if (ret < 0) > + return ret; > > - return rngc->err_reg ? -EIO : 0; > + return readl(rngc->base + RNGC_ERROR) ? -EIO : 0; > } > > static int imx_rngc_read(struct hwrng *rng, void *data, size_t max, bool > wait) -- TQ-Systems GmbH | Mühlstraße 2, Gut Delling | 82229 Seefeld, Germany Amtsgericht München, HRB 105018 Geschäftsführer: Detlef Schneider, Rüdiger Stahl, Stefan Schneider http://www.tq-group.com/