arm: bcmbca: add bcm6856 SoC support under CONFIG_ARCH_BCMBCA

BCM6856 is a Broadcom B53 based PON Gateway SoC. It is part of the BCA
(Broadband Carrier Access origin) chipset family. Like other Broadband
SoC, this patch adds it under CONFIG_BCM6856 chip config and
CONFIG_ARCH_BCMBCA platform config.

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.

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

Signed-off-by: William Zhang <william.zhang@broadcom.com>
Reviewed-by: Philippe Reynes <philippe.reynes@softathome.com>

MAINTAINERS

@@ -229,6 +229,7 @@ N:	bcm[9]?63178
 N:	bcm[9]?6756
 N:	bcm[9]?6813
 N:	bcm[9]?6846
+N:	bcm[9]?6856
 N:	bcm[9]?6878
 
 ARM BROADCOM BCMSTB

arch/arm/dts/Makefile

@@ -1199,6 +1199,8 @@ dtb-$(CONFIG_BCM6813) += \
 	bcm96813.dtb
 dtb-$(CONFIG_BCM6846) += \
 	bcm96846.dtb
+dtb-$(CONFIG_BCM6856) += \
+	bcm96856.dtb
 dtb-$(CONFIG_BCM6878) += \
 	bcm96878.dtb
 

arch/arm/dts/bcm6856.dtsi

@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright 2022 Broadcom Ltd.
+ */
+
+#include <dt-bindings/interrupt-controller/irq.h>
+#include <dt-bindings/interrupt-controller/arm-gic.h>
+
+/ {
+	compatible = "brcm,bcm6856", "brcm,bcmbca";
+	#address-cells = <2>;
+	#size-cells = <2>;
+
+	interrupt-parent = <&gic>;
+
+	cpus {
+		#address-cells = <2>;
+		#size-cells = <0>;
+
+		B53_0: cpu@0 {
+			compatible = "brcm,brahma-b53";
+			device_type = "cpu";
+			reg = <0x0 0x0>;
+			next-level-cache = <&L2_0>;
+			enable-method = "psci";
+		};
+
+		B53_1: cpu@1 {
+			compatible = "brcm,brahma-b53";
+			device_type = "cpu";
+			reg = <0x0 0x1>;
+			next-level-cache = <&L2_0>;
+			enable-method = "psci";
+		};
+
+		L2_0: l2-cache0 {
+			compatible = "cache";
+		};
+	};
+
+	timer {
+		compatible = "arm,armv8-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)>;
+	};
+
+	pmu: pmu {
+		compatible = "arm,cortex-a53-pmu";
+		interrupts = <GIC_SPI 9 IRQ_TYPE_LEVEL_HIGH>,
+			<GIC_SPI 10 IRQ_TYPE_LEVEL_HIGH>;
+		interrupt-affinity = <&B53_0>, <&B53_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 = <0x0 0x0 0x81000000 0x8000>;
+
+		gic: interrupt-controller@1000 {
+			compatible = "arm,gic-400";
+			#interrupt-cells = <3>;
+			interrupt-controller;
+			reg = <0x1000 0x1000>, /* GICD */
+				<0x2000 0x2000>, /* GICC */
+				<0x4000 0x2000>, /* GICH */
+				<0x6000 0x2000>; /* GICV */
+			interrupts = <GIC_PPI 9 (GIC_CPU_MASK_SIMPLE(2) |
+					IRQ_TYPE_LEVEL_HIGH)>;
+		};
+	};
+
+	bus@ff800000 {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		ranges = <0x0 0x0 0xff800000 0x800000>;
+
+		uart0: serial@640 {
+			compatible = "brcm,bcm6345-uart";
+			reg = <0x640 0x18>;
+			interrupts = <GIC_SPI 32 IRQ_TYPE_LEVEL_HIGH>;
+			clocks = <&periph_clk>;
+			clock-names = "refclk";
+			status = "disabled";
+		};
+	};
+};

arch/arm/dts/bcm96856.dts

@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright 2022 Broadcom Ltd.
+ */
+
+/dts-v1/;
+
+#include "bcm6856.dtsi"
+
+/ {
+	model = "Broadcom BCM96856 Reference Board";
+	compatible = "brcm,bcm96856", "brcm,bcm6856", "brcm,bcmbca";
+
+	aliases {
+		serial0 = &uart0;
+	};
+
+	chosen {
+		stdout-path = "serial0:115200n8";
+	};
+
+	memory@0 {
+		device_type = "memory";
+		reg = <0x0 0x0 0x0 0x08000000>;
+	};
+};
+
+&uart0 {
+	status = "okay";
+};

arch/arm/mach-bcmbca/Kconfig

@@ -83,6 +83,16 @@ config BCM6846
 	select DM_SERIAL
 	select BCM6345_SERIAL
 
+config BCM6856
+	bool "Support for Broadcom 6856 Family"
+	select ARM64
+	select SYS_ARCH_TIMER
+	select DM_SERIAL
+	select BCM6345_SERIAL
+	help
+	  Broadcom BCM6856 is a dual core Brahma-B53 ARMv8 based xPON Gateway
+	  SoC. This SoC family includes BCM6856, BCM6836 and BCM4910.
+
 config BCM6878
 	bool "Support for Broadcom 6878 Family"
 	select SYS_ARCH_TIMER
@@ -101,6 +111,7 @@ source "arch/arm/mach-bcmbca/bcm63178/Kconfig"
 source "arch/arm/mach-bcmbca/bcm6756/Kconfig"
 source "arch/arm/mach-bcmbca/bcm6813/Kconfig"
 source "arch/arm/mach-bcmbca/bcm6846/Kconfig"
+source "arch/arm/mach-bcmbca/bcm6856/Kconfig"
 source "arch/arm/mach-bcmbca/bcm6878/Kconfig"
 
 endif

arch/arm/mach-bcmbca/Makefile

@@ -14,4 +14,5 @@ obj-$(CONFIG_BCM63178) += bcm63178/
 obj-$(CONFIG_BCM6756) += bcm6756/
 obj-$(CONFIG_BCM6813) += bcm6813/
 obj-$(CONFIG_BCM6846) += bcm6846/
+obj-$(CONFIG_BCM6856) += bcm6856/
 obj-$(CONFIG_BCM6878) += bcm6878/

arch/arm/mach-bcmbca/bcm6856/Kconfig

@@ -0,0 +1,17 @@
+# SPDX-License-Identifier: GPL-2.0+
+#
+# (C) Copyright 2022 Broadcom Ltd
+#
+
+if BCM6856
+
+config TARGET_BCM96856
+	bool "Broadcom 6856 Reference Board"
+	depends on ARCH_BCMBCA
+
+config SYS_SOC
+	default "bcm6856"
+
+source "board/broadcom/bcmbca/Kconfig"
+
+endif

arch/arm/mach-bcmbca/bcm6856/Makefile

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

arch/arm/mach-bcmbca/bcm6856/mmu_table.c

@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ *  Copyright 2022 Broadcom Ltd.
+ */
+#include <common.h>
+#include <asm/armv8/mmu.h>
+#include <linux/sizes.h>
+
+static struct mm_region bcm96856_mem_map[] = {
+		{
+				.virt = 0x00000000UL,
+				.phys = 0x00000000UL,
+				.size = 1UL * SZ_1G,
+				.attrs = PTE_BLOCK_MEMTYPE(MT_NORMAL) |
+						PTE_BLOCK_INNER_SHARE
+		},
+		{
+				/* SoC peripheral */
+				.virt = 0xff800000UL,
+				.phys = 0xff800000UL,
+				.size = 0x100000,
+				.attrs = PTE_BLOCK_MEMTYPE(MT_DEVICE_NGNRNE) |
+						PTE_BLOCK_NON_SHARE |
+						PTE_BLOCK_PXN | PTE_BLOCK_UXN
+		},
+		{
+				/* List terminator */
+				0,
+		}
+};
+
+struct mm_region *mem_map = bcm96856_mem_map;

board/broadcom/bcmbca/Kconfig

@@ -86,6 +86,13 @@ config SYS_CONFIG_NAME
 
 endif
 
+if TARGET_BCM96856
+
+config SYS_CONFIG_NAME
+	default "bcm96856"
+
+endif
+
 if TARGET_BCM96878
 
 config SYS_CONFIG_NAME

configs/bcm96856_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_BCM6856=y
+CONFIG_TARGET_BCM96856=y
+CONFIG_NR_DRAM_BANKS=2
+CONFIG_DEFAULT_DEVICE_TREE="bcm96856"
+CONFIG_IDENT_STRING=" Broadcom BCM6856"
+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/bcm96856.h

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * (C) Copyright 2022 Broadcom Ltd.
+ */
+
+#ifndef __BCM96856_H
+#define __BCM96856_H
+
+#define CONFIG_SYS_SDRAM_BASE		0x00000000
+
+#endif