bcm27xx: import latest patches from the RPi foundation

bcm2708: boot tested on RPi B+ v1.2
bcm2709: boot tested on RPi 3B v1.2 and RPi 4B v1.1 4G
bcm2710: boot tested on RPi 3B v1.2
bcm2711: boot tested on RPi 4B v1.1 4G

Signed-off-by: Álvaro Fernández Rojas <noltari@gmail.com>

1 files changed, 70 insertions, 0 deletions

diff --git a/target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch b/target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch
new file mode 100644
index 0000000000..3ce5e0bbd3
--- /dev/null
+++ b/target/linux/bcm27xx/patches-5.4/950-0963-overlays-Update-i2c0-overlay-to-disable-the-i2c0mux.patch
@@ -0,0 +1,70 @@
+From 2be1e1c949138b40aac6be1e6f761c69e98dcf66 Mon Sep 17 00:00:00 2001
+From: Dave Stevenson <dave.stevenson@raspberrypi.com>
+Date: Thu, 3 Sep 2020 14:59:40 +0100
+Subject: [PATCH] overlays: Update i2c0 overlay to disable the
+ i2c0mux.
+
+The i2c0 overlay was assigning pinctrl settings to node i2c0,
+which is now the port@0 output of the mux. That leaves a high
+chance of it colliding with the port@1 output and not doing
+what was intended.
+
+Set the i2c0 overlay to disable i2c0mux, set the pin-ctrl on
+the root i2c controller, and redirect the alias, so overall it
+behaves exactly as before.
+Combining with dtparam=i2c_vc=on is going to cause conflicts,
+so this is noted in the README.
+
+Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>
+---
+ arch/arm/boot/dts/overlays/README           |  7 +++++++
+ arch/arm/boot/dts/overlays/i2c0-overlay.dts | 15 ++++++++++++++-
+ 2 files changed, 21 insertions(+), 1 deletion(-)
+
+--- a/arch/arm/boot/dts/overlays/README
++++ b/arch/arm/boot/dts/overlays/README
+@@ -1354,6 +1354,13 @@ Name:   i2c0
+ Info:   Change i2c0 pin usage. Not all pin combinations are usable on all
+         platforms - platforms other then Compute Modules can only use this
+         to disable transaction combining.
++        Do NOT use in conjunction with dtparam=i2c_vc=on. From the 5.4 kernel
++        onwards the base DT includes the use of i2c_mux_pinctrl to expose two
++        muxings of BSC0 - GPIOs 0&1, and whichever combination is used for the
++        camera and display connectors. This overlay disables that mux and
++        configures /dev/i2c0 to point at whichever set of pins is requested.
++        dtparam=i2c_vc=on will try and enable the mux, so combining the two
++        will cause conflicts.
+ Load:   dtoverlay=i2c0,<param>=<val>
+ Params: pins_0_1                Use pins 0 and 1 (default)
+         pins_28_29              Use pins 28 and 29
+--- a/arch/arm/boot/dts/overlays/i2c0-overlay.dts
++++ b/arch/arm/boot/dts/overlays/i2c0-overlay.dts
+@@ -5,7 +5,7 @@
+ 	compatible = "brcm,bcm2835";
+ 
+ 	fragment@0 {
+-		target = <&i2c0>;
++		target = <&i2c0if>;
+ 		__overlay__ {
+ 			status = "okay";
+ 			pinctrl-0 = <&i2c0_pins>;
+@@ -51,6 +51,19 @@
+ 		};
+ 	};
+ 
++	fragment@6 {
++		target = <&i2c0mux>;
++		__overlay__ {
++			status = "disabled";
++		};
++	};
++
++	fragment@7 {
++		target-path = "/aliases";
++		__overlay__ {
++			i2c0 = "/soc/i2c@7e205000";
++		};
++	};
+ 	__overrides__ {
+ 		pins_0_1   = <0>,"+1-2-3-4";
+ 		pins_28_29 = <0>,"-1+2-3-4";