ARM: Add basic support for Airoha EN7523 SoC

EN7523 is an armv8 based silicon used inside broadband access type devices
such as xPON and xDSL. It shares various silicon blocks with MediaTek
silicon such as the MT7622.

Add basic support for Airoha EN7523, enough for booting to console.

The UART is basically 8250-compatible, except for the clock selection.
A clock-frequency value is synthesized to get this to run at 115200 bps.

Signed-off-by: John Crispin <john@phrozen.org>
Signed-off-by: Bert Vermeulen <bert@biot.com>
Signed-off-by: Felix Fietkau <nbd@nbd.name>
Link: https://lore.kernel.org/r/20220130145116.88406-4-nbd@nbd.name
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com>

3 files changed, 146 insertions, 0 deletions

diff --git a/arch/arm/boot/dts/Makefile b/arch/arm/boot/dts/Makefile
index 235ad559acb2..e240ce638910 100644
--- a/arch/arm/boot/dts/Makefile
+++ b/arch/arm/boot/dts/Makefile
@@ -187,6 +187,8 @@ dtb-$(CONFIG_ARCH_DAVINCI) += \
 	da850-lego-ev3.dtb
 dtb-$(CONFIG_ARCH_DIGICOLOR) += \
 	cx92755_equinox.dtb
+dtb-$(CONFIG_ARCH_AIROHA) += \
+	en7523-evb.dtb
 dtb-$(CONFIG_ARCH_EXYNOS3) += \
 	exynos3250-artik5-eval.dtb \
 	exynos3250-monk.dtb \
diff --git a/arch/arm/boot/dts/en7523-evb.dts b/arch/arm/boot/dts/en7523-evb.dts
new file mode 100644
index 000000000000..69754ef9a628
--- /dev/null
+++ b/arch/arm/boot/dts/en7523-evb.dts
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+/dts-v1/;
+
+/* Bootloader installs ATF here */
+/memreserve/ 0x80000000 0x200000;
+
+#include "en7523.dtsi"
+
+/ {
+	model = "Airoha EN7523 Evaluation Board";
+	compatible = "airoha,en7523-evb", "airoha,en7523";
+
+	aliases {
+		serial0 = &uart1;
+	};
+
+	chosen {
+		bootargs = "console=ttyS0,115200 earlycon";
+		stdout-path = "serial0:115200n8";
+		linux,usable-memory-range = <0x80200000 0x1fe00000>;
+	};
+
+	memory@80000000 {
+		device_type = "memory";
+		reg = <0x80000000 0x20000000>;
+	};
+};
diff --git a/arch/arm/boot/dts/en7523.dtsi b/arch/arm/boot/dts/en7523.dtsi
new file mode 100644
index 000000000000..f1d4c03aad89
--- /dev/null
+++ b/arch/arm/boot/dts/en7523.dtsi
@@ -0,0 +1,117 @@
+// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+/ {
+	interrupt-parent = <&gic>;
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	reserved-memory {
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges;
+
+		npu_binary@84000000 {
+			no-map;
+			reg = <0x84000000 0xA00000>;
+		};
+
+		npu_flag@84B0000 {
+			no-map;
+			reg = <0x84B00000 0x100000>;
+		};
+
+		npu_pkt@85000000 {
+			no-map;
+			reg = <0x85000000 0x1A00000>;
+		};
+
+		npu_phyaddr@86B00000 {
+			no-map;
+			reg = <0x86B00000 0x100000>;
+		};
+
+		npu_rxdesc@86D00000 {
+			no-map;
+			reg = <0x86D00000 0x100000>;
+		};
+	};
+
+	psci {
+		compatible = "arm,psci-0.2";
+		method = "smc";
+	};
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu-map {
+			cluster0 {
+				core0 {
+					cpu = <&cpu0>;
+				};
+				core1 {
+					cpu = <&cpu1>;
+				};
+			};
+		};
+
+		cpu0: cpu@0 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a53";
+			reg = <0x0>;
+			enable-method = "psci";
+			clock-frequency = <80000000>;
+			next-level-cache = <&L2_0>;
+		};
+
+		cpu1: cpu@1 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a53";
+			reg = <0x1>;
+			enable-method = "psci";
+			clock-frequency = <80000000>;
+			next-level-cache = <&L2_0>;
+		};
+
+		L2_0: l2-cache0 {
+			compatible = "cache";
+		};
+	};
+
+	gic: interrupt-controller@9000000 {
+		compatible = "arm,gic-v3";
+		interrupt-controller;
+		#interrupt-cells = <3>;
+		#address-cells = <1>;
+		#size-cells = <1>;
+		reg = <0x09000000 0x20000>,
+		      <0x09080000 0x80000>,
+		      <0x09400000 0x2000>,
+		      <0x09500000 0x2000>,
+		      <0x09600000 0x20000>;
+		interrupts = <GIC_PPI 9 IRQ_TYPE_LEVEL_LOW>;
+	};
+
+	timer {
+		compatible = "arm,armv8-timer";
+		interrupt-parent = <&gic>;
+		interrupts = <GIC_PPI 13 IRQ_TYPE_LEVEL_LOW>,
+			     <GIC_PPI 14 IRQ_TYPE_LEVEL_LOW>,
+			     <GIC_PPI 11 IRQ_TYPE_LEVEL_LOW>,
+			     <GIC_PPI 10 IRQ_TYPE_LEVEL_LOW>;
+	};
+
+	uart1: serial@1fbf0000 {
+		compatible = "ns16550";
+		reg = <0x1fbf0000 0x30>;
+		reg-io-width = <4>;
+		reg-shift = <2>;
+		interrupts = <GIC_SPI 18 IRQ_TYPE_LEVEL_HIGH>;
+		clock-frequency = <1843200>;
+		status = "okay";
+	};
+};