[PATCH v2] hwrng: bcm2835: set quality to 1000

Álvaro Fernández Rojas noltari at gmail.com
Sat Feb 20 14:57:48 EST 2021


This allows devices without a high precission timer to speed up boot from
more 100 s to lest than 30s.

Justification:
root at OpenWrt:/# cat /dev/hwrng | rngtest -c 1000
rngtest 6.10
Copyright (c) 2004 by Henrique de Moraes Holschuh
This is free software; see the source for copying conditions.  There is NO
warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.

rngtest: starting FIPS tests...
rngtest: bits received from input: 20000032
rngtest: FIPS 140-2 successes: 996
rngtest: FIPS 140-2 failures: 4
rngtest: FIPS 140-2(2001-10-10) Monobit: 0
rngtest: FIPS 140-2(2001-10-10) Poker: 0
rngtest: FIPS 140-2(2001-10-10) Runs: 1
rngtest: FIPS 140-2(2001-10-10) Long run: 3
rngtest: FIPS 140-2(2001-10-10) Continuous run: 0
rngtest: input channel speed: (min=146.002; avg=349.394;
max=1302083.333)Kibits/s
rngtest: FIPS tests speed: (min=12.126; avg=22.750; max=23.432)Mibits/s
rngtest: Program run time: 56826982 microseconds

996 successes and 4 failures -> 99.6% success rate
1024 * 99.6% = 1019 (rounded down to 1000)

Signed-off-by: Álvaro Fernández Rojas <noltari at gmail.com>
---
 v2: add jusftification

 drivers/char/hw_random/bcm2835-rng.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c
index 1a7c43b43c6b..4b48cb7176b0 100644
--- a/drivers/char/hw_random/bcm2835-rng.c
+++ b/drivers/char/hw_random/bcm2835-rng.c
@@ -163,6 +163,7 @@ static int bcm2835_rng_probe(struct platform_device *pdev)
 	priv->rng.init = bcm2835_rng_init;
 	priv->rng.read = bcm2835_rng_read;
 	priv->rng.cleanup = bcm2835_rng_cleanup;
+	priv->rng.quality = 1000;
 
 	if (dev_of_node(dev)) {
 		rng_id = of_match_node(bcm2835_rng_of_match, dev->of_node);
-- 
2.20.1




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