arm: bcmbca: add bcm6846 SoC support

BCM6846 is an ARM A7 based PON Broadband SoC. It is part of the BCA
(Broadband Carrier Access origin) chipset family so it's added under
ARCH_BCMBCA platform. This initial support includes a bare-bone
implementation and dts with CPU subsystem, memory and Broadcom uart.

This SoC is supported in the linux-next git repository so the dts and
dtsi files are copied from linux with minor fix-up that needs to be
upstreamed to linux as well.

The u-boot image can be loaded from flash or network to the entry point
address in the memory and boot from there.

Signed-off-by: William Zhang <william.zhang@broadcom.com>

MAINTAINERS

@@ -219,6 +219,7 @@ F:	board/broadcom/bcmbca/
 N:	bcmbca
 N:	bcm[9]?47622
 N:	bcm[9]?63178
+N:	bcm[9]?6846
 
 ARM BROADCOM BCMSTB
 M:	Thomas Fitzsimmons <fitzsim@fitzsim.org>

arch/arm/dts/Makefile

@@ -1184,6 +1184,8 @@ dtb-$(CONFIG_BCM47622) += \
 	bcm947622.dtb
 dtb-$(CONFIG_BCM63178) += \
 	bcm963178.dtb
+dtb-$(CONFIG_BCM6846) += \
+	bcm96846.dtb
 
 dtb-$(CONFIG_ASPEED_AST2500) += ast2500-evb.dtb
 dtb-$(CONFIG_ASPEED_AST2600) += ast2600-evb.dtb

arch/arm/dts/bcm6846.dtsi

@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright 2022 Broadcom Ltd.
+ */
+
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+#include <dt-bindings/interrupt-controller/irq.h>
+
+/ {
+	compatible = "brcm,bcm6846", "brcm,bcmbca";
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	interrupt-parent = <&gic>;
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		CA7_0: cpu@0 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a7";
+			reg = <0x0>;
+			next-level-cache = <&L2_0>;
+			enable-method = "psci";
+		};
+
+		CA7_1: cpu@1 {
+			device_type = "cpu";
+			compatible = "arm,cortex-a7";
+			reg = <0x1>;
+			next-level-cache = <&L2_0>;
+			enable-method = "psci";
+		};
+
+		L2_0: l2-cache0 {
+			compatible = "cache";
+		};
+	};
+
+	timer {
+		compatible = "arm,armv7-timer";
+		interrupts = <GIC_PPI 13 (GIC_CPU_MASK_SIMPLE(2) | IRQ_TYPE_LEVEL_LOW)>,
+			<GIC_PPI 14 (GIC_CPU_MASK_SIMPLE(2) | IRQ_TYPE_LEVEL_LOW)>,
+			<GIC_PPI 11 (GIC_CPU_MASK_SIMPLE(2) | IRQ_TYPE_LEVEL_LOW)>,
+			<GIC_PPI 10 (GIC_CPU_MASK_SIMPLE(2) | IRQ_TYPE_LEVEL_LOW)>;
+		arm,cpu-registers-not-fw-configured;
+	};
+
+	pmu: pmu {
+		compatible = "arm,cortex-a7-pmu";
+		interrupts = <GIC_SPI 9 IRQ_TYPE_LEVEL_HIGH>,
+			<GIC_SPI 10 IRQ_TYPE_LEVEL_HIGH>;
+		interrupt-affinity = <&CA7_0>, <&CA7_1>;
+	};
+
+	clocks: clocks {
+		periph_clk: periph-clk {
+			compatible = "fixed-clock";
+			#clock-cells = <0>;
+			clock-frequency = <200000000>;
+		};
+	};
+
+	psci {
+		compatible = "arm,psci-0.2";
+		method = "smc";
+	};
+
+	axi@81000000 {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0 0x81000000 0x8000>;
+
+		gic: interrupt-controller@1000 {
+			compatible = "arm,cortex-a7-gic";
+			#interrupt-cells = <3>;
+			interrupt-controller;
+			interrupts = <GIC_PPI 9 (GIC_CPU_MASK_SIMPLE(2) | IRQ_TYPE_LEVEL_HIGH)>;
+			reg = <0x1000 0x1000>,
+				<0x2000 0x2000>,
+				<0x4000 0x2000>,
+				<0x6000 0x2000>;
+		};
+	};
+
+	bus@ff800000 {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0 0xff800000 0x800000>;
+
+		uart0: serial@640 {
+			compatible = "brcm,bcm6345-uart";
+			reg = <0x640 0x1b>;
+			interrupts = <GIC_SPI 92 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&periph_clk>;
+			clock-names = "refclk";
+			status = "disabled";
+		};
+	};
+};

arch/arm/dts/bcm96846.dts

@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright 2022 Broadcom Ltd.
+ */
+
+/dts-v1/;
+
+#include "bcm6846.dtsi"
+
+/ {
+	model = "Broadcom BCM96846 Reference Board";
+	compatible = "brcm,bcm96846", "brcm,bcm6846", "brcm,bcmbca";
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x0 0x08000000>;
+	};
+};
+
+&uart0 {
+	status = "okay";
+};

arch/arm/mach-bcmbca/Kconfig

@@ -19,7 +19,15 @@ config BCM63178
 	select DM_SERIAL
 	select PL01X_SERIAL
 
+config BCM6846
+	bool "Support for Broadcom 6846 Family"
+	select SYS_ARCH_TIMER
+	select CPU_V7A
+	select DM_SERIAL
+	select BCM6345_SERIAL
+
 source "arch/arm/mach-bcmbca/bcm47622/Kconfig"
 source "arch/arm/mach-bcmbca/bcm63178/Kconfig"
+source "arch/arm/mach-bcmbca/bcm6846/Kconfig"
 
 endif

arch/arm/mach-bcmbca/Makefile

@@ -5,3 +5,4 @@
 
 obj-$(CONFIG_BCM47622) += bcm47622/
 obj-$(CONFIG_BCM63178) += bcm63178/
+obj-$(CONFIG_BCM6846) += bcm6846/

arch/arm/mach-bcmbca/bcm6846/Kconfig

@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright 2022 Broadcom Ltd
+#
+
+if BCM6846
+
+config TARGET_BCM96846
+	bool "Broadcom 6846 Reference Board"
+	depends on ARCH_BCMBCA
+
+config SYS_SOC
+	default "bcm6846"
+
+source "board/broadcom/bcmbca/Kconfig"
+
+endif

arch/arm/mach-bcmbca/bcm6846/Makefile

@@ -0,0 +1,5 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright 2022 Broadcom Ltd
+#
+obj- += dummy.o

board/broadcom/bcmbca/Kconfig

@@ -22,3 +22,10 @@ config SYS_CONFIG_NAME
 	default "bcm963178"
 
 endif
+
+if TARGET_BCM96846
+
+config SYS_CONFIG_NAME
+	default "bcm96846"
+
+endif

configs/bcm96846_defconfig

@@ -0,0 +1,23 @@
+CONFIG_ARM=y
+CONFIG_COUNTER_FREQUENCY=50000000
+CONFIG_ARCH_BCMBCA=y
+CONFIG_SYS_TEXT_BASE=0x01000000
+CONFIG_SYS_MALLOC_LEN=0x2000000
+CONFIG_SYS_MALLOC_F_LEN=0x8000
+CONFIG_BCM6846=y
+CONFIG_TARGET_BCM96846=y
+CONFIG_NR_DRAM_BANKS=1
+CONFIG_DEFAULT_DEVICE_TREE="bcm96846"
+CONFIG_IDENT_STRING=" Broadcom BCM6846"
+CONFIG_SYS_LOAD_ADDR=0x01000000
+CONFIG_ENV_VARS_UBOOT_CONFIG=y
+CONFIG_HAS_CUSTOM_SYS_INIT_SP_ADDR=y
+CONFIG_CUSTOM_SYS_INIT_SP_ADDR=0x2000000
+CONFIG_OF_STDOUT_VIA_ALIAS=y
+CONFIG_DISPLAY_BOARDINFO_LATE=y
+CONFIG_HUSH_PARSER=y
+CONFIG_SYS_MAXARGS=64
+CONFIG_SYS_BOOTM_LEN=0x4000000
+CONFIG_CMD_CACHE=y
+CONFIG_OF_EMBED=y
+CONFIG_CLK=y

include/configs/bcm96846.h

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2022 Broadcom Ltd.
+ */
+
+#ifndef __BCM96846_H
+#define __BCM96846_H
+
+#define CONFIG_SYS_SDRAM_BASE		0x00000000
+
+#endif