diff options
Diffstat (limited to 'target/linux/brcm2708/patches-4.14/950-0308-overlays-Add-sdtweak-features-for-network-booting.patch')
| -rw-r--r-- | target/linux/brcm2708/patches-4.14/950-0308-overlays-Add-sdtweak-features-for-network-booting.patch | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/target/linux/brcm2708/patches-4.14/950-0308-overlays-Add-sdtweak-features-for-network-booting.patch b/target/linux/brcm2708/patches-4.14/950-0308-overlays-Add-sdtweak-features-for-network-booting.patch new file mode 100644 index 0000000000..8ed0f0aa40 --- /dev/null +++ b/target/linux/brcm2708/patches-4.14/950-0308-overlays-Add-sdtweak-features-for-network-booting.patch @@ -0,0 +1,51 @@ +From eadd32681787b1828ff92ef5046db6568d52ad55 Mon Sep 17 00:00:00 2001 +From: Phil Elwell <phil@raspberrypi.org> +Date: Tue, 29 May 2018 10:52:11 +0100 +Subject: [PATCH 308/454] overlays: Add sdtweak features for network booting + +It has been observed that a Pi with no SD card will poll the interface +continuously, using up to 10% CPU. Add some new parameters to the +sdtweak overlay to control this behaviour: + +poll_once Only look for a card once, at boot time. If none is found + then the interface is effectively disabled. + +enable Set to "off" or "no" to completely disable the interface. + +See: https://github.com/raspberrypi/linux/issues/2567 + +Signed-off-by: Phil Elwell <phil@raspberrypi.org> +--- + arch/arm/boot/dts/overlays/README | 10 ++++++++++ + arch/arm/boot/dts/overlays/sdtweak-overlay.dts | 2 ++ + 2 files changed, 12 insertions(+) + +--- a/arch/arm/boot/dts/overlays/README ++++ b/arch/arm/boot/dts/overlays/README +@@ -1618,6 +1618,16 @@ Params: overclock_50 Clock (i + + debug Enable debug output (default off) + ++ poll_once Looks for a card once after booting. Useful ++ for network booting scenarios to avoid the ++ overhead of continuous polling. N.B. Using ++ this option restricts the system to using a ++ single card per boot (or none at all). ++ (default off) ++ ++ enable Set to off to completely disable the interface ++ (default on) ++ + + Name: smi + Info: Enables the Secondary Memory Interface peripheral. Uses GPIOs 2-25! +--- a/arch/arm/boot/dts/overlays/sdtweak-overlay.dts ++++ b/arch/arm/boot/dts/overlays/sdtweak-overlay.dts +@@ -19,5 +19,7 @@ + force_pio = <&frag0>,"brcm,force-pio?"; + pio_limit = <&frag0>,"brcm,pio-limit:0"; + debug = <&frag0>,"brcm,debug?"; ++ enable = <&frag0>,"status"; ++ poll_once = <&frag0>,"non-removable?"; + }; + }; |