ARM: dts: aspeed: Add Facebook Backpack-CMM BMC

Add initial version of device tree file for Facebook Backpack CMM (Chasis Management Module) ast2500 BMC.

Note: I2C devices on Backpack Line Cards and Fabric Cards are not listed in the device tree file because Line/Fabric Cards may be unplugged.

Signed-off-by Tao Ren <[email protected]>

---
Changes since v1:
- including "aspeed-bmc-facebook-cmm.dtb" in Makefile.

 arch/arm/boot/dts/Makefile                    |   1 +
 arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts | 317 ++++++++++++++++++
 2 files changed, 318 insertions(+)
 create mode 100644 arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts

arch/arm/boot/dts/Makefile +1 -0

index a7c313bfe490..2239e6a30d7a 100644
@@ -1200,6 +1200,7 @@ dtb-$(CONFIG_ARCH_ASPEED) += \
 	aspeed-ast2500-evb.dtb \
 	aspeed-bmc-arm-centriq2400-rep.dtb \
 	aspeed-bmc-arm-stardragon4800-rep2.dtb \
+	aspeed-bmc-facebook-cmm.dtb \
 	aspeed-bmc-facebook-tiogapass.dtb \
 	aspeed-bmc-intel-s2600wf.dtb \
 	aspeed-bmc-opp-lanyang.dtb \

arch/arm/ renamed from arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts +0 -0

boot/dts/aspeed-bmc-facebook-cmm.dts
new file mode 100644
index 000000000000..a259d8a2426a

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +62 -0

@@ -0,0 +1,317 @@
+// SPDX-License-Identifier: GPL-2.0+
+// Copyright (c) 2018 Facebook Inc.
+/dts-v1/;
+
+#include "aspeed-g5.dtsi"
+
+/ {
+	model = "Facebook Backpack CMM BMC";
+	compatible = "facebook,cmm-bmc", "aspeed,ast2500";
+
+	aliases {
+		/*
+		 * Override the default uart aliases to avoid breaking
+		 * the legacy applications.
+		 */
+		serial0 = &uart5;
+		serial1 = &uart1;
+		serial2 = &uart3;
+		serial3 = &uart4;
+
+		/*
+		 * Hardcode the bus number of i2c switches' channels to
+		 * avoid breaking the legacy applications.
+		 */
+		i2c16 = &imux16;
+		i2c17 = &imux17;
+		i2c18 = &imux18;
+		i2c19 = &imux19;
+		i2c20 = &imux20;
+		i2c21 = &imux21;
+		i2c22 = &imux22;
+		i2c23 = &imux23;
+		i2c24 = &imux24;
+		i2c25 = &imux25;
+		i2c26 = &imux26;
+		i2c27 = &imux27;
+		i2c28 = &imux28;
+		i2c29 = &imux29;
+		i2c30 = &imux30;
+		i2c31 = &imux31;
+		i2c32 = &imux32;
+		i2c33 = &imux33;
+		i2c34 = &imux34;
+		i2c35 = &imux35;
+		i2c36 = &imux36;
+		i2c37 = &imux37;
+		i2c38 = &imux38;
+		i2c39 = &imux39;
+	};
+
+	chosen {
+		stdout-path = &uart1;
+		bootargs = "console=ttyS1,9600n8 root=/dev/ram rw earlyprintk";
+	};
+
+	memory at 80000000 {
+		reg = <0x80000000 0x20000000>;
+	};
+};
+
+/*
+ * Update reset type to "system" (full chip) to fix warm reboot hang 

issue
+ * when reset type is set to default ("soc", gated by reset mask registers).
+ */
+&wdt1 {

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +22 -0

+	status = "okay";
+	aspeed,reset-type = "system";
+};
+
+/*
+ * wdt2 is not used by Backpack CMM.
+ */
+&wdt2 {
+	status = "disabled";
+};
+
+&fmc {
+	status = "okay";
+	flash at 0 {
+		status = "okay";
+		m25p,fast-read;
+		label = "bmc";
+#include "facebook-bmc-flash-layout.dtsi"
+	};
+};
+
+&uart1 {

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +202 -0

+
+&mac1 {
+	status = "okay";
+	no-hw-checksum;
+	pinctrl-names = "default";
+	pinctrl-0 = <&pinctrl_rgmii2_default &pinctrl_mdio2_default>;
+};
+
+&i2c0 {
+	status = "okay";
+};
+
+&i2c1 {
+	status = "okay";
+
+	i2c-switch at 77 {
+		compatible = "nxp,pca9548";
+		#address-cells = <1>;
+		#size-cells = <0>;
+		reg = <0x77>;
+
+		imux16: i2c at 0 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <0>;
+		};
+
+		imux17: i2c at 1 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <1>;
+		};
+
+		imux18: i2c at 2 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <2>;
+		};
+
+		imux19: i2c at 3 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <3>;
+		};
+
+		imux20: i2c at 4 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <4>;
+		};
+
+		imux21: i2c at 5 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <5>;
+		};
+
+		imux22: i2c at 6 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <6>;
+		};
+
+		imux23: i2c at 7 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <7>;
+		};
+	};
+};
+
+&i2c2 {
+	status = "okay";
+
+	i2c-switch at 71 {
+		compatible = "nxp,pca9548";
+		#address-cells = <1>;
+		#size-cells = <0>;
+		reg = <0x71>;
+
+		imux24: i2c at 0 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <0>;
+		};
+
+		imux25: i2c at 1 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <1>;
+		};
+
+		imux26: i2c at 2 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <2>;
+		};
+
+		imux27: i2c at 3 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <3>;
+		};
+
+		imux28: i2c at 4 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <4>;
+		};
+
+		imux29: i2c at 5 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <5>;
+		};
+
+		imux30: i2c at 6 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <6>;
+		};
+
+		imux31: i2c at 7 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <7>;
+		};
+	};
+};
+
+&i2c3 {
+	status = "okay";
+};
+
+&i2c4 {
+	status = "okay";
+};
+
+&i2c5 {
+	status = "okay";
+};
+
+&i2c6 {
+	status = "okay";
+};
+
+&i2c7 {
+	status = "okay";
+};
+
+&i2c8 {
+	status = "okay";
+
+	i2c-switch at 77 {
+		compatible = "nxp,pca9548";
+		#address-cells = <1>;
+		#size-cells = <0>;
+		reg = <0x77>;
+
+		imux32: i2c at 0 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <0>;
+		};
+
+		imux33: i2c at 1 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <1>;
+		};
+
+		imux34: i2c at 2 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <2>;
+		};
+
+		imux35: i2c at 3 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <3>;
+		};
+
+		imux36: i2c at 4 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <4>;
+		};
+
+		imux37: i2c at 5 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <5>;
+		};
+
+		imux38: i2c at 6 {
+			#address-cells = <1>;
+			#size-cells = <0>;
+			reg = <6>;
+		};
+
+		imux39: i2c at 7 {

Note: I2C devices on Backpack Line Cards and Fabric Cards are not listed in the device tree file because Line/Fabric Cards may be unplugged.

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +4 -0

+
+&adc {
+	status = "okay";
+};

Signature · 1 line

2.17.1

Quoted 5 lines

+&uart1 {

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +4 -0

+	status = "okay";
+};
+
+&uart3 {

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts line 97

Quoted 6 lines

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +6 -0

+	status = "okay";
+};
+
+&uart4 {
+	status = "okay";
+};

UARTs 1-4 should be explicitly pinmuxed. It's a bit fiddly as each of the UART lines has its own mux configuration, but it at least allows some flexibility (i.e. whether you just want Rx/Tx, or something more). See e.g. the uart1 node in arch/arm/boot/dts/aspeed-bmc-opp-romulus.dts.

Speaking of pinctrl, as it's an AST2500 system you'll probably want to add the following to ensure you have full control of the pinmux configuration:

&pinctrl {
	aspeed,external-nodes = <&gfx &lhc>;
};

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts line 101

Quoted 4 lines

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +4 -0

+
+&uart5 {
+	status = "okay";
+};

UART5 has fixed pins, so no pinctrl necessary here.

You said this in the commit message:

Quoted 3 lines

Note: I2C devices on Backpack Line Cards and Fabric Cards are not listed in the device tree file because Line/Fabric Cards may be unplugged.

It's not clear to me what this actually means, and I'm trying to reconcile it with enabling all of the i2c buses as I'm curious as to whether that's necessary.

Quoted 5 lines · Andrew Jeffery

Quoted 5 lines

+&uart1 {

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +4 -0

+	status = "okay";
+};
+
+&uart3 {

Quoted 8 lines

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts line 97

Quoted 6 lines

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +6 -0

+	status = "okay";
+};
+
+&uart4 {
+	status = "okay";
+};

UARTs 1-4 should be explicitly pinmuxed. It's a bit fiddly as each of the UART lines has its own mux configuration, but it at least allows some flexibility (i.e. whether you just want Rx/Tx, or something more). See e.g. the uart1 node in arch/arm/boot/dts/aspeed-bmc-opp-romulus.dts.

Thank you for pointing it out and I will fix it.

Quoted 6 lines

Speaking of pinctrl, as it's an AST2500 system you'll probably want to add the following to ensure you have full control of the pinmux configuration:

&pinctrl {
	aspeed,external-nodes = <&gfx &lhc>;
};

Quoted 6 lines

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts line 101

Quoted 4 lines

arch/arm/boot/dts/aspeed-bmc-facebook-cmm.dts new file +4 -0

+
+&uart5 {
+	status = "okay";
+};

UART5 has fixed pins, so no pinctrl necessary here.

Got it. Thank you.

Quoted 6 lines

You said this in the commit message:

Quoted 3 lines

Note: I2C devices on Backpack Line Cards and Fabric Cards are not listed in the device tree file because Line/Fabric Cards may be unplugged.

Quoted 1 line

It's not clear to me what this actually means, and I'm trying to reconcile it with enabling all of the i2c buses as I'm curious as to whether that's necessary.

Sorry for the confusion. In general, all the i2c buses are initialized in device tree, but i2c leaf devices are created from user space because these i2c devices may be unplugged at boot time (which causes driver_probe failures).

Let me refine the commit message and will send
out updated patch soon.

Thanks,
Tao Ren