This allows devices without a high precission timer to speed up boot from more than 100s to lest than 30s.
BCM2835 rngtest: root@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) BCM6368 rngtest: root@OpenWrt:/# root@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: 751 rngtest: FIPS 140-2 failures: 249 rngtest: FIPS 140-2(2001-10-10) Monobit: 0 rngtest: FIPS 140-2(2001-10-10) Poker: 34 rngtest: FIPS 140-2(2001-10-10) Runs: 245 rngtest: FIPS 140-2(2001-10-10) Long run: 0 rngtest: FIPS 140-2(2001-10-10) Continuous run: 0 rngtest: input channel speed: (min=1.202; avg=16.434; max=1003.868)Mibits/s rngtest: FIPS tests speed: (min=761.155; avg=8343.383; max=15662.590)Kibits/s rngtest: Program run time: 3539183 microseconds cat: write error: Broken pipe Signed-off-by: Álvaro Fernández Rojas <nolt...@gmail.com> --- v3: set different qualities for each SoC v2: add jusftification drivers/char/hw_random/bcm2835-rng.c | 17 ++++++++++++++--- 1 file changed, 14 insertions(+), 3 deletions(-) diff --git a/drivers/char/hw_random/bcm2835-rng.c b/drivers/char/hw_random/bcm2835-rng.c index 1a7c43b43c6b..a6121a04f624 100644 --- a/drivers/char/hw_random/bcm2835-rng.c +++ b/drivers/char/hw_random/bcm2835-rng.c @@ -121,6 +121,15 @@ static void bcm2835_rng_cleanup(struct hwrng *rng) struct bcm2835_rng_of_data { bool mask_interrupts; + unsigned short quality; +}; + +static const struct bcm2835_rng_of_data bcm283x_rng_of_data = { + .quality = 1000, +}; + +static const struct bcm2835_rng_of_data bcm6368_rng_of_data = { + .quality = 700, }; static const struct bcm2835_rng_of_data nsp_rng_of_data = { @@ -128,10 +137,10 @@ static const struct bcm2835_rng_of_data nsp_rng_of_data = { }; static const struct of_device_id bcm2835_rng_of_match[] = { - { .compatible = "brcm,bcm2835-rng"}, + { .compatible = "brcm,bcm2835-rng", .data = &bcm283x_rng_of_data }, { .compatible = "brcm,bcm-nsp-rng", .data = &nsp_rng_of_data }, { .compatible = "brcm,bcm5301x-rng", .data = &nsp_rng_of_data }, - { .compatible = "brcm,bcm6368-rng"}, + { .compatible = "brcm,bcm6368-rng", .data = &bcm6368_rng_of_data }, {}, }; @@ -171,8 +180,10 @@ static int bcm2835_rng_probe(struct platform_device *pdev) /* Check for rng init function, execute it */ of_data = rng_id->data; - if (of_data) + if (of_data) { priv->mask_interrupts = of_data->mask_interrupts; + priv->rng.quality = of_data->quality; + } } /* register driver */ -- 2.20.1