brcm2708: update to latest patches from RPi Foundation

[openwrt/staging/chunkeey.git] / target / linux / brcm2708 / patches-4.19 / 950-0020-bcm2835-rng-Avoid-initialising-if-already-enabled.patch

diff --git a/target/linux/brcm2708/patches-4.19/950-0020-bcm2835-rng-Avoid-initialising-if-already-enabled.patch b/target/linux/brcm2708/patches-4.19/950-0020-bcm2835-rng-Avoid-initialising-if-already-enabled.patch
new file mode 100644 (file)
index 0000000..30ab050
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0020-bcm2835-rng-Avoid-initialising-if-already-enabled.patch
@@ -0,0 +1,25 @@
+From d5df60f32f3c3b2f7f6d758ac08de6acb9fd947f 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 | 6 ++++--
+ 1 file changed, 4 insertions(+), 2 deletions(-)
+
+--- a/drivers/char/hw_random/bcm2835-rng.c
++++ b/drivers/char/hw_random/bcm2835-rng.c
+@@ -105,8 +105,10 @@ static int bcm2835_rng_init(struct hwrng
+       }
+ 
+       /* set warm-up count & enable */
+-      rng_writel(priv, RNG_WARMUP_COUNT, RNG_STATUS);
+-      rng_writel(priv, RNG_RBGEN, RNG_CTRL);
++      if (!(rng_readl(priv, RNG_CTRL) & RNG_RBGEN)) {
++              rng_writel(priv, RNG_WARMUP_COUNT, RNG_STATUS);
++              rng_writel(priv, RNG_RBGEN, RNG_CTRL);
++      }
+ 
+       return ret;
+ }