diff mbox series

[v2,1/6] hwrng: imx-rngc - reasonable timeout for selftest

Message ID 20230824192059.1569591-2-martin@kaiser.cx
State Superseded
Headers show
Series hwrng: imx-rngc - use polling instead of interrupt | expand

Commit Message

Martin Kaiser Aug. 24, 2023, 7:20 p.m. UTC 
Set a more reasonable timeout for the rngc selftest.

According to the reference manual, "The self test takes approximately
29,000 cycles to complete." With the rngc peripheral clock running at
66.5 MHz, this would be 436us. Let's use 1.5ms insteaf of 3sec for the
timeout.

Signed-off-by: Martin Kaiser <martin@kaiser.cx>
---
v2:
- adjust timeouts before we switch to polling

 drivers/char/hw_random/imx-rngc.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/drivers/char/hw_random/imx-rngc.c b/drivers/char/hw_random/imx-rngc.c
index e4b385b01b11..6024c923b67d 100644
--- a/drivers/char/hw_random/imx-rngc.c
+++ b/drivers/char/hw_random/imx-rngc.c
@@ -53,6 +53,7 @@ 
 
 #define RNGC_TIMEOUT  3000 /* 3 sec */
 
+#define RNGC_SELFTEST_TIMEOUT 1500 /* us */
 
 static bool self_test = true;
 module_param(self_test, bool, 0);
@@ -110,7 +111,8 @@  static int imx_rngc_self_test(struct imx_rngc *rngc)
 	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));
+	ret = wait_for_completion_timeout(&rngc->rng_op_done,
+					  usecs_to_jiffies(RNGC_SELFTEST_TIMEOUT));
 	imx_rngc_irq_mask_clear(rngc);
 	if (!ret)
 		return -ETIMEDOUT;