diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.4/0561-bcm2835-rng-Avoid-initialising-if-already-enabled.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.4/0561-bcm2835-rng-Avoid-initialising-if-already-enabled.patch | 26 |
1 files changed, 26 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.4/0561-bcm2835-rng-Avoid-initialising-if-already-enabled.patch b/target/linux/brcm2708/patches-4.4/0561-bcm2835-rng-Avoid-initialising-if-already-enabled.patch new file mode 100644 index 0000000..b8cc66c --- /dev/null +++ b/target/linux/brcm2708/patches-4.4/0561-bcm2835-rng-Avoid-initialising-if-already-enabled.patch @@ -0,0 +1,26 @@ +From ad841f8241807114d61572c1ca1636e7a43e6d93 Mon Sep 17 00:00:00 2001 +From: popcornmix <popcornmix@gmail.com> +Date: Tue, 6 Dec 2016 17:05:39 +0000 +Subject: [PATCH] bcm2835-rng: Avoid initialising if already enabled + +Avoids the 0x40000 cycles of warmup again if firmware has already used it +--- + drivers/char/hw_random/bcm2835-rng.c | 7 ++++--- + 1 file changed, 4 insertions(+), 3 deletions(-) + +--- a/drivers/char/hw_random/bcm2835-rng.c ++++ b/drivers/char/hw_random/bcm2835-rng.c +@@ -62,9 +62,10 @@ static int bcm2835_rng_probe(struct plat + bcm2835_rng_ops.priv = (unsigned long)rng_base; + + /* set warm-up count & enable */ +- __raw_writel(RNG_WARMUP_COUNT, rng_base + RNG_STATUS); +- __raw_writel(RNG_RBGEN, rng_base + RNG_CTRL); +- ++ if (!(__raw_readl(rng_base + RNG_CTRL) & RNG_RBGEN)) { ++ __raw_writel(RNG_WARMUP_COUNT, rng_base + RNG_STATUS); ++ __raw_writel(RNG_RBGEN, rng_base + RNG_CTRL); ++ } + /* register driver */ + err = hwrng_register(&bcm2835_rng_ops); + if (err) { |