[PATCH v3 4/4] arm64: dts: ti: Enable MCU MCANs for AM62x

[Judith Mendez]

On AM62x there are no hardware interrupts routed to A53 GIC
interrupt controller for MCU MCAN IPs, so MCU MCANs were not
added to the MCU dtsi. In this patch series an hrtimer is introduced
to MCAN driver to generate software interrupts. Now add MCU MCAN
nodes to the MCU dtsi but disable the MCAN devices by default.

AM62x does not carry on-board CAN transceivers, so instead of
changing DTB permanently use an overlay to enable MCU MCANs and to
add CAN transceiver nodes.

If there is no hardware interrupt and timer method is used, remove
interrupt properties and add poll-interval to enable the hrtimer
per MCAN node.

This DT overlay can be used with the following EVM:
Link: https://www.ti.com/tool/TCAN1042DEVM

Signed-off-by: Judith Mendez <jm at ti.com>
---
Changelog:
v3:
 1. Add link for specific board

 arch/arm64/boot/dts/ti/Makefile               |  2 +-
 arch/arm64/boot/dts/ti/k3-am62-mcu.dtsi       | 24 ++++++++
 .../boot/dts/ti/k3-am625-sk-mcan-mcu.dtso     | 57 +++++++++++++++++++
 3 files changed, 82 insertions(+), 1 deletion(-)
 create mode 100644 arch/arm64/boot/dts/ti/k3-am625-sk-mcan-mcu.dtso

diff --git a/arch/arm64/boot/dts/ti/Makefile b/arch/arm64/boot/dts/ti/Makefile
index abe15e76b614..c76be3888e4d 100644
--- a/arch/arm64/boot/dts/ti/Makefile
+++ b/arch/arm64/boot/dts/ti/Makefile
@@ -9,7 +9,7 @@
 # alphabetically.
 
 # Boards with AM62x SoC
-k3-am625-sk-mcan-dtbs := k3-am625-sk.dtb k3-am625-sk-mcan-main.dtbo
+k3-am625-sk-mcan-dtbs := k3-am625-sk.dtb k3-am625-sk-mcan-main.dtbo k3-am625-sk-mcan-mcu.dtbo
 dtb-$(CONFIG_ARCH_K3) += k3-am625-beagleplay.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am625-sk.dtb
 dtb-$(CONFIG_ARCH_K3) += k3-am625-sk-mcan.dtb
diff --git a/arch/arm64/boot/dts/ti/k3-am62-mcu.dtsi b/arch/arm64/boot/dts/ti/k3-am62-mcu.dtsi
index 076601a41e84..20462f457643 100644
--- a/arch/arm64/boot/dts/ti/k3-am62-mcu.dtsi
+++ b/arch/arm64/boot/dts/ti/k3-am62-mcu.dtsi
@@ -141,4 +141,28 @@
 		/* Tightly coupled to M4F */
 		status = "reserved";
 	};
+
+	mcu_mcan1: can at 4e00000 {
+		compatible = "bosch,m_can";
+		reg = <0x00 0x4e00000 0x00 0x8000>,
+			  <0x00 0x4e08000 0x00 0x200>;
+		reg-names = "message_ram", "m_can";
+		power-domains = <&k3_pds 188 TI_SCI_PD_EXCLUSIVE>;
+		clocks = <&k3_clks 188 6>, <&k3_clks 188 1>;
+		clock-names = "hclk", "cclk";
+		bosch,mram-cfg = <0x0 128 64 64 64 64 32 32>;
+		status = "disabled";
+	};
+
+	mcu_mcan2: can at 4e10000 {
+		compatible = "bosch,m_can";
+		reg = <0x00 0x4e10000 0x00 0x8000>,
+			  <0x00 0x4e18000 0x00 0x200>;
+		reg-names = "message_ram", "m_can";
+		power-domains = <&k3_pds 189 TI_SCI_PD_EXCLUSIVE>;
+		clocks = <&k3_clks 189 6>, <&k3_clks 189 1>;
+		clock-names = "hclk", "cclk";
+		bosch,mram-cfg = <0x0 128 64 64 64 64 32 32>;
+		status = "disabled";
+	};
 };
diff --git a/arch/arm64/boot/dts/ti/k3-am625-sk-mcan-mcu.dtso b/arch/arm64/boot/dts/ti/k3-am625-sk-mcan-mcu.dtso
new file mode 100644
index 000000000000..5145b3de4f9b
--- /dev/null
+++ b/arch/arm64/boot/dts/ti/k3-am625-sk-mcan-mcu.dtso
@@ -0,0 +1,57 @@
+// SPDX-License-Identifier: GPL-2.0
+/**
+ * DT overlay for MCAN in MCU domain on AM625 SK
+ *
+ * Copyright (C) 2022 Texas Instruments Incorporated - https://www.ti.com/
+ */
+
+/dts-v1/;
+/plugin/;
+
+#include "k3-pinctrl.h"
+
+&{/} {
+	transceiver2: can-phy1 {
+		compatible = "ti,tcan1042";
+		#phy-cells = <0>;
+		max-bitrate = <5000000>;
+	};
+
+	transceiver3: can-phy2 {
+		compatible = "ti,tcan1042";
+		#phy-cells = <0>;
+		max-bitrate = <5000000>;
+	};
+};
+
+&mcu_pmx0 {
+	mcu_mcan1_pins_default: mcu-mcan1-pins-default {
+		pinctrl-single,pins = <
+			AM62X_IOPAD(0x038, PIN_INPUT, 0) /* (B3) MCU_MCAN0_RX */
+			AM62X_IOPAD(0x034, PIN_OUTPUT, 0) /* (D6) MCU_MCAN0_TX */
+		>;
+	};
+
+	mcu_mcan2_pins_default: mcu-mcan2-pins-default {
+		pinctrl-single,pins = <
+			AM62X_IOPAD(0x040, PIN_INPUT, 0) /* (D4) MCU_MCAN1_RX */
+			AM62X_IOPAD(0x03C, PIN_OUTPUT, 0) /* (E5) MCU_MCAN1_TX */
+		>;
+	};
+};
+
+&mcu_mcan1 {
+	poll-interval;
+	pinctrl-names = "default";
+	pinctrl-0 = <&mcu_mcan1_pins_default>;
+	phys = <&transceiver2>;
+	status = "okay";
+};
+
+&mcu_mcan2 {
+	poll-interval;
+	pinctrl-names = "default";
+	pinctrl-0 = <&mcu_mcan2_pins_default>;
+	phys = <&transceiver3>;
+	status = "okay";
+};
-- 
2.17.1