Commit 50fb6d5c authored by Martin Kaiser's avatar Martin Kaiser Committed by Herbert Xu
Browse files

hwrng: imx-rngc - reasonable timeout for initial seed 



Set a more reasonable timeout for calculating the initial seed.

The reference manuals says that "The initial seed takes approximately
2,000,000 clock cycles." The rngc peripheral clock runs at >= 33.25MHz,
so seeding takes at most 60ms.

A timeout of 200ms is more appropriate than the current value of 3
seconds.

Signed-off-by: default avatarMartin Kaiser <martin@kaiser.cx>
Signed-off-by: default avatarHerbert Xu <herbert@gondor.apana.org.au>
parent b6c6044b

drivers/char/hw_random/imx-rngc.c

+3 −3
Original line number Diff line number Diff line
@@ -51,9 +51,8 @@ 


#define RNGC_ERROR_STATUS_STAT_ERR	0x00000008



#define RNGC_TIMEOUT  3000 /* 3 sec */



#define RNGC_SELFTEST_TIMEOUT 2500 /* us */

#define RNGC_SEED_TIMEOUT      200 /* ms */



static bool self_test = true;

module_param(self_test, bool, 0);
@@ -184,7 +183,8 @@ static int imx_rngc_init(struct hwrng *rng) 
		cmd = readl(rngc->base + RNGC_COMMAND);

		writel(cmd | RNGC_CMD_SEED, 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,

						  msecs_to_jiffies(RNGC_SEED_TIMEOUT));

		if (!ret) {

			ret = -ETIMEDOUT;

			goto err;