[PATCH 0/3] ARC: [plat-hsdk-4xd] initial port for HSDK-4xD board

[PATCH 0/3] ARC: [plat-hsdk-4xd] initial port for HSDK-4xD board

[Eugeniy Paltsev]

Eugeniy Paltsev (3):
  ARC: allow to overide default mcpu compiler flag
  ARC: ARCv2: support loop buffer (LPB) disabling
  ARC: [plat-hsdk-4xd] initial port for HSDK-4xD board

 arch/arc/Kconfig                    |  13 ++
 arch/arc/Makefile                   |   4 +
 arch/arc/boot/dts/hsdk-4xd.dts      | 322 ++++++++++++++++++++++++++++
 arch/arc/configs/hsdk_4xd_defconfig |  99 +++++++++
 arch/arc/kernel/devtree.c           |   1 +
 arch/arc/kernel/head.S              |   8 +
 arch/arc/plat-hsdk/Kconfig          |  24 ++-
 arch/arc/plat-hsdk/platform.c       |   6 +
 8 files changed, 476 insertions(+), 1 deletion(-)
 create mode 100644 arch/arc/boot/dts/hsdk-4xd.dts
 create mode 100644 arch/arc/configs/hsdk_4xd_defconfig

-- 
2.21.3

[PATCH 1/3] ARC: allow to overide default mcpu compiler flag

[Eugeniy Paltsev]

By default we set -mcpu=xxx compiler flag depending on the CPU ISA
version. It's good starting point, however that may be not enough
as for some platforms we may want to use some specific 'mcpu'
options for better optimization or to workaround HW issues.

We are going to use this option for HSDK-4xD board support.
In addition it also allows to awoid patching 'mcpu' in ARC Makefile
when we building Linux for some non-standard simulation or FPGA-based
platforms.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
---
 arch/arc/Kconfig  | 7 +++++++
 arch/arc/Makefile | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index ff306246d0f8..2d4f85dc914e 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -377,6 +377,13 @@ config ARC_HAS_SWAPE
 	bool "Insn: SWAPE (endian-swap)"
 	default y
 
+config ARC_TUNE_MCPU
+	string "Overide default -mcpu compiler flag"
+	default ""
+	help
+	  Overide default -mcpu=xxx compiler flag (which is set depending on
+	  the ISA version) with the specified value.
+
 if ISA_ARCV2
 
 config ARC_USE_UNALIGNED_MEM_ACCESS
diff --git a/arch/arc/Makefile b/arch/arc/Makefile
index 20e9ab6cc521..eb88ba5b1573 100644
--- a/arch/arc/Makefile
+++ b/arch/arc/Makefile
@@ -10,8 +10,12 @@ CROSS_COMPILE := $(call cc-cross-prefix, arc-linux- arceb-linux-)
 endif
 
 cflags-y	+= -fno-common -pipe -fno-builtin -mmedium-calls -D__linux__
+ifeq ($(CONFIG_ARC_TUNE_MCPU),"")
 cflags-$(CONFIG_ISA_ARCOMPACT)	+= -mA7
 cflags-$(CONFIG_ISA_ARCV2)	+= -mcpu=hs38
+else
+cflags-y			+= $(shell echo $(CONFIG_ARC_TUNE_MCPU))
+endif
 
 ifdef CONFIG_ARC_CURR_IN_REG
 # For a global register defintion, make sure it gets passed to every file
-- 
2.21.3

[PATCH private 1/3] ARC: allow to overwrite default mcpu compiler flag

[Eugeniy Paltsev]

By default we set -mcpu=xxx compiler flag depending on the CPU ISA
version. It's good starting point, however that may be not enough
as for some platforms we may want to use some specific 'mcpu'
options for better optimization or to workaround HW issues.

We are going to use this option for HSDK-4xD board support.
In addition it also allows to awoid patching 'mcpu' in ARC Makefile
when we building Linux for some non-standard simulation or FPGA-based
platforms.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
---
 arch/arc/Kconfig  | 7 +++++++
 arch/arc/Makefile | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index ff306246d0f8..e7805db10f7a 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -377,6 +377,13 @@ config ARC_HAS_SWAPE
 	bool "Insn: SWAPE (endian-swap)"
 	default y
 
+config ARC_MCPU_OVERWRITE
+	string "Overwrite default -mcpu compiler flag"
+	default ""
+	help
+	  Overwrite default -mcpu=xxx compiler flag (which is set depending on
+	  the ISA version) with the specified value.
+
 if ISA_ARCV2
 
 config ARC_USE_UNALIGNED_MEM_ACCESS
diff --git a/arch/arc/Makefile b/arch/arc/Makefile
index 20e9ab6cc521..1b37e44d9b57 100644
--- a/arch/arc/Makefile
+++ b/arch/arc/Makefile
@@ -10,8 +10,12 @@ CROSS_COMPILE := $(call cc-cross-prefix, arc-linux- arceb-linux-)
 endif
 
 cflags-y	+= -fno-common -pipe -fno-builtin -mmedium-calls -D__linux__
+ifeq ($(CONFIG_ARC_MCPU_OVERWRITE),"")
 cflags-$(CONFIG_ISA_ARCOMPACT)	+= -mA7
 cflags-$(CONFIG_ISA_ARCV2)	+= -mcpu=hs38
+else
+cflags-y			+= $(shell echo $(CONFIG_ARC_MCPU_OVERWRITE))
+endif
 
 ifdef CONFIG_ARC_CURR_IN_REG
 # For a global register defintion, make sure it gets passed to every file
-- 
2.21.3

[PATCH 2/3] ARC: ARCv2: support loop buffer (LPB) disabling

[Eugeniy Paltsev]

On HS cores, loop buffer (LPB) is programmable in runtime and can
be optionally disabled.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
---
 arch/arc/Kconfig       | 6 ++++++
 arch/arc/kernel/head.S | 8 ++++++++
 2 files changed, 14 insertions(+)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index 2d4f85dc914e..270504d4fdf5 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -471,6 +471,12 @@ config ARC_IRQ_NO_AUTOSAVE
 	  This is programmable and can be optionally disabled in which case
 	  software INTERRUPT_PROLOGUE/EPILGUE do the needed work
 
+config ARC_LPB_DISABLE
+	bool "Disable loop buffer (LPB)"
+	help
+	  On HS cores, loop buffer (LPB) is programmable in runtime and can
+	  be optionally disabled.
+
 endif # ISA_ARCV2
 
 endmenu   # "ARC CPU Configuration"
diff --git a/arch/arc/kernel/head.S b/arch/arc/kernel/head.S
index 6eb23f1545ee..17fd1ed700cc 100644
--- a/arch/arc/kernel/head.S
+++ b/arch/arc/kernel/head.S
@@ -59,6 +59,14 @@
 	bclr	r5, r5, STATUS_AD_BIT
 #endif
 	kflag	r5
+
+#ifdef CONFIG_ARC_LPB_DISABLE
+	lr	r5, [ARC_REG_LPB_BUILD]
+	breq    r5, 0, 1f		; LPB doesn't exist
+	mov	r5, 1
+	sr	r5, [ARC_REG_LPB_CTRL]
+1:
+#endif /* CONFIG_ARC_LPB_DISABLE */
 #endif
 	; Config DSP_CTRL properly, so kernel may use integer multiply,
 	; multiply-accumulate, and divide operations
-- 
2.21.3

[PATCH 3/3] ARC: [plat-hsdk-4xd] initial port for HSDK-4xD board

[Eugeniy Paltsev]

This initial port adds support of ARC HS4x/HS4xD Development Kit board with some
basic features such serial port, USB, SD/MMC, SPI flash, Ethernet and others.

The HSDK-4xD board has much in common with its predecessor - HSDK board.
However HSDK-4xD has some differences in comparison with its predecessor:
 * based on quad core ARC HS48/HS47D processor (instead of quad core ARC HS38)
 * has ThinkSilicon GPU (instead of Vivante GPU)
 * has ARC PGU and HDMI output
 * has separate SDIO controller for WiFi module
 * has additional timers with clocksource independent from CPU clocksource
   (required for DVFS)
 * has performance counters interrupt
 * other minor stuff

NOTE:
HSDK-4xD and HSDK may share significant part of DTS so we can move this common
part to one .dtsi file (as we have done it in U-boot). However we have quite
enough out of the tree patches for tweaking HSDK DTS (patches in out
verification flow, patches for run in simulation, etc...), so I'd prefer to
keep HSDK DTS untouched. That's why HSDK-4xD DTS is created as an separate file.

Cc: Rob Herring <robh+dt@kernel.org>
Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
---
 arch/arc/boot/dts/hsdk-4xd.dts      | 322 ++++++++++++++++++++++++++++
 arch/arc/configs/hsdk_4xd_defconfig |  99 +++++++++
 arch/arc/kernel/devtree.c           |   1 +
 arch/arc/plat-hsdk/Kconfig          |  24 ++-
 arch/arc/plat-hsdk/platform.c       |   6 +
 5 files changed, 451 insertions(+), 1 deletion(-)
 create mode 100644 arch/arc/boot/dts/hsdk-4xd.dts
 create mode 100644 arch/arc/configs/hsdk_4xd_defconfig

diff --git a/arch/arc/boot/dts/hsdk-4xd.dts b/arch/arc/boot/dts/hsdk-4xd.dts
new file mode 100644
index 000000000000..2b7f76a01e3e
--- /dev/null
+++ b/arch/arc/boot/dts/hsdk-4xd.dts
@@ -0,0 +1,322 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
+ */
+
+/*
+ * Device Tree for ARC HS4x/HS4xD Development Kit
+ */
+/dts-v1/;
+
+#include <dt-bindings/gpio/gpio.h>
+#include <dt-bindings/reset/snps,hsdk-reset.h>
+
+/ {
+	model = "snps,hsdk-4xd";
+	compatible = "snps,hsdk-4xd";
+
+	#address-cells = <2>;
+	#size-cells = <2>;
+
+	chosen {
+		bootargs = "earlycon=uart8250,mmio32,0xf0005000,115200n8 console=ttyS0,115200n8 debug print-fatal-signals=1";
+	};
+
+	aliases {
+		ethernet = &gmac;
+	};
+
+	cpus {
+		#address-cells = <1>;
+		#size-cells = <0>;
+
+		cpu@0 {
+			device_type = "cpu";
+			compatible = "snps,archs48";
+			reg = <0>;
+			clocks = <&core_clk>;
+		};
+
+		cpu@1 {
+			device_type = "cpu";
+			compatible = "snps,archs48";
+			reg = <1>;
+			clocks = <&core_clk>;
+		};
+
+		cpu@2 {
+			device_type = "cpu";
+			compatible = "snps,archs48";
+			reg = <2>;
+			clocks = <&core_clk>;
+		};
+
+		cpu@3 {
+			device_type = "cpu";
+			compatible = "snps,archs48";
+			reg = <3>;
+			clocks = <&core_clk>;
+		};
+	};
+
+	input_clk: input-clk {
+		#clock-cells = <0>;
+		compatible = "fixed-clock";
+		clock-frequency = <33333333>;
+	};
+
+	reg_5v0: regulator-5v0 {
+		compatible = "regulator-fixed";
+
+		regulator-name = "5v0-supply";
+		regulator-min-microvolt = <5000000>;
+		regulator-max-microvolt = <5000000>;
+	};
+
+	cpu_intc: cpu-interrupt-controller {
+		compatible = "snps,archs-intc";
+		interrupt-controller;
+		#interrupt-cells = <1>;
+	};
+
+	idu_intc: idu-interrupt-controller {
+		compatible = "snps,archs-idu-intc";
+		interrupt-controller;
+		#interrupt-cells = <1>;
+		interrupt-parent = <&cpu_intc>;
+	};
+
+	arcpct: pct {
+		compatible = "snps,archs-pct";
+		interrupt-parent = <&cpu_intc>;
+		interrupts = <20>;
+	};
+
+	/* TIMER0 with interrupt for clockevent */
+	timer {
+		compatible = "snps,arc-timer";
+		interrupts = <16>;
+		interrupt-parent = <&cpu_intc>;
+		clocks = <&core_clk>;
+	};
+
+	/* 64-bit Global Free Running Counter */
+	gfrc {
+		compatible = "snps,archs-timer-gfrc";
+		clocks = <&core_clk>;
+	};
+
+	soc {
+		compatible = "simple-bus";
+		#address-cells = <1>;
+		#size-cells = <1>;
+		interrupt-parent = <&idu_intc>;
+
+		ranges = <0x00000000 0x0 0xf0000000 0x10000000>;
+
+		cgu_rst: reset-controller@8a0 {
+			compatible = "snps,hsdk-reset";
+			#reset-cells = <1>;
+			reg = <0x8a0 0x4>, <0xff0 0x4>;
+		};
+
+		core_clk: core-clk@0 {
+			compatible = "snps,hsdk-core-pll-clock";
+			reg = <0x00 0x10>, <0x14b8 0x4>;
+			#clock-cells = <0>;
+			clocks = <&input_clk>;
+
+			/*
+			 * Set initial core pll output frequency to 1GHz.
+			 * It will be applied at the core pll driver probing
+			 * on early boot.
+			 */
+			assigned-clocks = <&core_clk>;
+			assigned-clock-rates = <1000000000>;
+		};
+
+		serial: serial@5000 {
+			compatible = "snps,dw-apb-uart";
+			reg = <0x5000 0x100>;
+			clock-frequency = <33330000>;
+			interrupts = <6>;
+			baud = <115200>;
+			reg-shift = <2>;
+			reg-io-width = <4>;
+		};
+
+		gmacclk: gmacclk {
+			compatible = "fixed-clock";
+			clock-frequency = <400000000>;
+			#clock-cells = <0>;
+		};
+
+		mmcclk_ciu: mmcclk-ciu {
+			compatible = "fixed-clock";
+			/*
+			 * DW sdio controller has external ciu clock divider
+			 * controlled via register in SDIO IP. Due to its
+			 * unexpected default value (it should divide by 1
+			 * but it divides by 8) SDIO IP uses wrong clock and
+			 * works unstable (see STAR 9001204800)
+			 * We switched to the minimum possible value of the
+			 * divisor (div-by-2) in HSDK platform code.
+			 * So add temporary fix and change clock frequency
+			 * to 50000000 Hz until we fix dw sdio driver itself.
+			 */
+			clock-frequency = <50000000>;
+			#clock-cells = <0>;
+		};
+
+		mmcclk_biu: mmcclk-biu {
+			compatible = "fixed-clock";
+			clock-frequency = <400000000>;
+			#clock-cells = <0>;
+		};
+
+		dmac_core_clk: dmac-core-clk {
+			compatible = "fixed-clock";
+			clock-frequency = <400000000>;
+			#clock-cells = <0>;
+		};
+
+		dmac_cfg_clk: dmac-gpu-cfg-clk {
+			compatible = "fixed-clock";
+			clock-frequency = <200000000>;
+			#clock-cells = <0>;
+		};
+
+		gmac: ethernet@8000 {
+			#interrupt-cells = <1>;
+			compatible = "snps,dwmac";
+			reg = <0x8000 0x2000>;
+			interrupts = <10>;
+			interrupt-names = "macirq";
+			phy-mode = "rgmii";
+			snps,pbl = <32>;
+			snps,multicast-filter-bins = <256>;
+			clocks = <&gmacclk>;
+			clock-names = "stmmaceth";
+			phy-handle = <&phy0>;
+			resets = <&cgu_rst HSDK_ETH_RESET>;
+			reset-names = "stmmaceth";
+			mac-address = [00 00 00 00 00 00]; /* Filled in by U-Boot */
+			dma-coherent;
+
+			tx-fifo-depth = <4096>;
+			rx-fifo-depth = <4096>;
+
+			mdio {
+				#address-cells = <1>;
+				#size-cells = <0>;
+				compatible = "snps,dwmac-mdio";
+				phy0: ethernet-phy@0 {
+					reg = <0>;
+				};
+			};
+		};
+
+		ohci@60000 {
+			compatible = "snps,hsdk-v1.0-ohci", "generic-ohci";
+			reg = <0x60000 0x100>;
+			interrupts = <15>;
+			resets = <&cgu_rst HSDK_USB_RESET>;
+			dma-coherent;
+		};
+
+		ehci@40000 {
+			compatible = "snps,hsdk-v1.0-ehci", "generic-ehci";
+			reg = <0x40000 0x100>;
+			interrupts = <15>;
+			resets = <&cgu_rst HSDK_USB_RESET>;
+			dma-coherent;
+		};
+
+		mmc@a000 {
+			compatible = "altr,socfpga-dw-mshc";
+			reg = <0xa000 0x400>;
+			num-slots = <1>;
+			fifo-depth = <16>;
+			card-detect-delay = <200>;
+			clocks = <&mmcclk_biu>, <&mmcclk_ciu>;
+			clock-names = "biu", "ciu";
+			interrupts = <12>;
+			bus-width = <4>;
+			dma-coherent;
+		};
+
+		spi0: spi@20000 {
+			compatible = "snps,dw-apb-ssi";
+			reg = <0x20000 0x100>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+			interrupts = <16>;
+			num-cs = <2>;
+			reg-io-width = <4>;
+			clocks = <&input_clk>;
+			cs-gpios = <&creg_gpio 0 GPIO_ACTIVE_LOW>,
+				   <&creg_gpio 1 GPIO_ACTIVE_LOW>;
+
+			spi-flash@0 {
+				compatible = "sst26wf016b", "jedec,spi-nor";
+				reg = <0>;
+				#address-cells = <1>;
+				#size-cells = <1>;
+				spi-max-frequency = <4000000>;
+			};
+
+			adc@1 {
+				compatible = "ti,adc108s102";
+				reg = <1>;
+				vref-supply = <&reg_5v0>;
+				spi-max-frequency = <1000000>;
+			};
+		};
+
+		creg_gpio: gpio@14b0 {
+			compatible = "snps,creg-gpio-hsdk";
+			reg = <0x14b0 0x4>;
+			gpio-controller;
+			#gpio-cells = <2>;
+			ngpios = <2>;
+		};
+
+		gpio: gpio@3000 {
+			compatible = "snps,dw-apb-gpio";
+			reg = <0x3000 0x20>;
+			#address-cells = <1>;
+			#size-cells = <0>;
+
+			gpio_port_a: gpio-controller@0 {
+				compatible = "snps,dw-apb-gpio-port";
+				gpio-controller;
+				#gpio-cells = <2>;
+				snps,nr-gpios = <24>;
+				reg = <0>;
+			};
+		};
+
+		dmac: dmac@80000 {
+			compatible = "snps,axi-dma-1.01a";
+			reg = <0x80000 0x400>;
+			interrupts = <27>;
+			clocks = <&dmac_core_clk>, <&dmac_cfg_clk>;
+			clock-names = "core-clk", "cfgr-clk";
+
+			dma-channels = <4>;
+			snps,dma-masters = <2>;
+			snps,data-width = <3>;
+			snps,block-size = <4096 4096 4096 4096>;
+			snps,priority = <0 1 2 3>;
+			snps,axi-max-burst-len = <16>;
+		};
+	};
+
+	memory@80000000 {
+		#address-cells = <2>;
+		#size-cells = <2>;
+		device_type = "memory";
+		reg = <0x0 0x80000000 0x0 0x40000000>;  /* 1 GB lowmem */
+		/*     0x1 0x00000000 0x0 0x40000000>;     1 GB highmem */
+	};
+};
diff --git a/arch/arc/configs/hsdk_4xd_defconfig b/arch/arc/configs/hsdk_4xd_defconfig
new file mode 100644
index 000000000000..bf78f745a0f6
--- /dev/null
+++ b/arch/arc/configs/hsdk_4xd_defconfig
@@ -0,0 +1,99 @@
+CONFIG_SYSVIPC=y
+# CONFIG_CROSS_MEMORY_ATTACH is not set
+CONFIG_NO_HZ_IDLE=y
+CONFIG_HIGH_RES_TIMERS=y
+CONFIG_PREEMPT=y
+CONFIG_IKCONFIG=y
+CONFIG_IKCONFIG_PROC=y
+CONFIG_NAMESPACES=y
+# CONFIG_UTS_NS is not set
+# CONFIG_PID_NS is not set
+CONFIG_BLK_DEV_INITRD=y
+CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3=y
+CONFIG_EMBEDDED=y
+CONFIG_PERF_EVENTS=y
+# CONFIG_VM_EVENT_COUNTERS is not set
+# CONFIG_COMPAT_BRK is not set
+CONFIG_SLAB=y
+CONFIG_ARC_SOC_HSDK=y
+CONFIG_ARC_BOARD_HSDK_4XD=y
+CONFIG_SMP=y
+CONFIG_ARC_TUNE_MCPU="-mcpu=hs4x_rel31"
+CONFIG_ARC_DSP_KERNEL=y
+CONFIG_LINUX_LINK_BASE=0x90000000
+CONFIG_LINUX_RAM_BASE=0x80000000
+CONFIG_ARC_BUILTIN_DTB_NAME="hsdk-4xd"
+CONFIG_JUMP_LABEL=y
+CONFIG_MODULES=y
+CONFIG_MODULE_UNLOAD=y
+# CONFIG_COMPACTION is not set
+CONFIG_NET=y
+CONFIG_PACKET=y
+CONFIG_UNIX=y
+CONFIG_INET=y
+CONFIG_DEVTMPFS=y
+# CONFIG_STANDALONE is not set
+# CONFIG_PREVENT_FIRMWARE_BUILD is not set
+CONFIG_MTD=y
+CONFIG_MTD_SPI_NOR=y
+CONFIG_BLK_DEV_RAM=y
+CONFIG_SCSI=y
+CONFIG_BLK_DEV_SD=y
+CONFIG_NETDEVICES=y
+CONFIG_STMMAC_ETH=y
+CONFIG_MICREL_PHY=y
+CONFIG_INPUT_EVDEV=y
+# CONFIG_INPUT_KEYBOARD is not set
+# CONFIG_INPUT_MOUSE is not set
+# CONFIG_SERIO is not set
+# CONFIG_LEGACY_PTYS is not set
+CONFIG_SERIAL_8250=y
+CONFIG_SERIAL_8250_CONSOLE=y
+CONFIG_SERIAL_8250_DW=y
+CONFIG_SERIAL_OF_PLATFORM=y
+# CONFIG_HW_RANDOM is not set
+CONFIG_SPI=y
+CONFIG_SPI_DESIGNWARE=y
+CONFIG_SPI_DW_MMIO=y
+CONFIG_GPIOLIB=y
+CONFIG_GPIO_SYSFS=y
+CONFIG_GPIO_DWAPB=y
+CONFIG_GPIO_SNPS_CREG=y
+# CONFIG_HWMON is not set
+CONFIG_THERMAL=y
+CONFIG_REGULATOR=y
+CONFIG_REGULATOR_FIXED_VOLTAGE=y
+CONFIG_DRM=y
+# CONFIG_DRM_FBDEV_EMULATION is not set
+CONFIG_DRM_UDL=y
+CONFIG_FB=y
+CONFIG_FRAMEBUFFER_CONSOLE=y
+CONFIG_USB=y
+CONFIG_USB_EHCI_HCD=y
+CONFIG_USB_EHCI_HCD_PLATFORM=y
+CONFIG_USB_OHCI_HCD=y
+CONFIG_USB_OHCI_HCD_PLATFORM=y
+CONFIG_USB_STORAGE=y
+CONFIG_MMC=y
+CONFIG_MMC_SDHCI=y
+CONFIG_MMC_SDHCI_PLTFM=y
+CONFIG_MMC_DW=y
+CONFIG_DMADEVICES=y
+CONFIG_DW_AXI_DMAC=y
+CONFIG_IIO=y
+CONFIG_TI_ADC108S102=y
+CONFIG_EXT3_FS=y
+CONFIG_VFAT_FS=y
+CONFIG_TMPFS=y
+CONFIG_NFS_FS=y
+CONFIG_NFS_V3_ACL=y
+CONFIG_NLS_CODEPAGE_437=y
+CONFIG_NLS_ISO8859_1=y
+CONFIG_CRYPTO_ECHAINIV=y
+# CONFIG_ENABLE_MUST_CHECK is not set
+CONFIG_STRIP_ASM_SYMS=y
+CONFIG_SOFTLOCKUP_DETECTOR=y
+CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
+# CONFIG_SCHED_DEBUG is not set
+# CONFIG_DEBUG_PREEMPT is not set
+# CONFIG_FTRACE is not set
diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c
index fa86d13df5ed..81f881af7356 100644
--- a/arch/arc/kernel/devtree.c
+++ b/arch/arc/kernel/devtree.c
@@ -27,6 +27,7 @@ static void __init arc_set_early_base_baud(unsigned long dt_root)
 	if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x"))
 		arc_base_baud = 166666666;	/* Fixed 166.6MHz clk (TB10x) */
 	else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") ||
+		 of_flat_dt_is_compatible(dt_root, "snps,hsdk-4xd") ||
 		 of_flat_dt_is_compatible(dt_root, "snps,hsdk"))
 		arc_base_baud = 33333333;	/* Fixed 33MHz clk (AXS10x & HSDK) */
 	else if (of_flat_dt_is_compatible(dt_root, "ezchip,arc-nps"))
diff --git a/arch/arc/plat-hsdk/Kconfig b/arch/arc/plat-hsdk/Kconfig
index ce8101834518..3bf80eceebae 100644
--- a/arch/arc/plat-hsdk/Kconfig
+++ b/arch/arc/plat-hsdk/Kconfig
@@ -3,10 +3,32 @@
 #
 
 menuconfig ARC_SOC_HSDK
-	bool "ARC HS Development Kit SOC"
+	bool "ARC HSDK or HSDK-4xD SoCs"
 	depends on ISA_ARCV2
 	select ARC_HAS_ACCL_REGS
 	select ARC_IRQ_NO_AUTOSAVE
 	select CLK_HSDK
 	select RESET_HSDK
 	select HAVE_PCI
+
+menu "HSDK / HSDK-4xD options"
+	visible if ARC_SOC_HSDK
+
+choice
+	prompt "HSDK board type"
+
+config ARC_BOARD_HSDK
+	bool "ARC HS Development Kit"
+	help
+	  ARC HS Development Kit based on quad core ARC HS38 processor
+
+config ARC_BOARD_HSDK_4XD
+	bool "ARC HS4x/HS4xD Development Kit"
+	select ARC_LPB_DISABLE
+	help
+	  ARC HS4x/HS4xD Development Kit based on quad core ARC HS48/HS47D
+	  processor
+
+endchoice
+
+endmenu
diff --git a/arch/arc/plat-hsdk/platform.c b/arch/arc/plat-hsdk/platform.c
index 0b961a2a10b8..74e2508cfd1e 100644
--- a/arch/arc/plat-hsdk/platform.c
+++ b/arch/arc/plat-hsdk/platform.c
@@ -331,7 +331,13 @@ static void __init hsdk_init_early(void)
 	hsdk_enable_gpio_intc_wire();
 }
 
+/*
+ * As we aren't going to run HSDK-4xD Linux image on HSDK and vise versa let's
+ * don't add additional machine entry but instead add new compatible to existing one and
+ * resolve all differences in compile time with #ifdef's.
+ */
 static const char *hsdk_compat[] __initconst = {
+	"snps,hsdk-4xd",
 	"snps,hsdk",
 	NULL,
 };
-- 
2.21.3

Re: [PATCH private 1/3] ARC: allow to overwrite default mcpu compiler flag

[Eugeniy Paltsev]

Oooops, this one is duplicate and should be dropped.

---
 Eugeniy Paltsev


________________________________________
From: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
Sent: Friday, May 29, 2020 14:55
To: linux-snps-arc@lists.infradead.org; Vineet Gupta
Cc: linux-kernel@vger.kernel.org; Alexey Brodkin; Eugeniy Paltsev
Subject: [PATCH private 1/3] ARC: allow to overwrite default mcpu compiler flag

By default we set -mcpu=xxx compiler flag depending on the CPU ISA
version. It's good starting point, however that may be not enough
as for some platforms we may want to use some specific 'mcpu'
options for better optimization or to workaround HW issues.

We are going to use this option for HSDK-4xD board support.
In addition it also allows to awoid patching 'mcpu' in ARC Makefile
when we building Linux for some non-standard simulation or FPGA-based
platforms.

Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
---
 arch/arc/Kconfig  | 7 +++++++
 arch/arc/Makefile | 4 ++++
 2 files changed, 11 insertions(+)

diff --git a/arch/arc/Kconfig b/arch/arc/Kconfig
index ff306246d0f8..e7805db10f7a 100644
--- a/arch/arc/Kconfig
+++ b/arch/arc/Kconfig
@@ -377,6 +377,13 @@ config ARC_HAS_SWAPE
        bool "Insn: SWAPE (endian-swap)"
        default y

+config ARC_MCPU_OVERWRITE
+       string "Overwrite default -mcpu compiler flag"
+       default ""
+       help
+         Overwrite default -mcpu=xxx compiler flag (which is set depending on
+         the ISA version) with the specified value.
+
 if ISA_ARCV2

 config ARC_USE_UNALIGNED_MEM_ACCESS
diff --git a/arch/arc/Makefile b/arch/arc/Makefile
index 20e9ab6cc521..1b37e44d9b57 100644
--- a/arch/arc/Makefile
+++ b/arch/arc/Makefile
@@ -10,8 +10,12 @@ CROSS_COMPILE := $(call cc-cross-prefix, arc-linux- arceb-linux-)
 endif

 cflags-y       += -fno-common -pipe -fno-builtin -mmedium-calls -D__linux__
+ifeq ($(CONFIG_ARC_MCPU_OVERWRITE),"")
 cflags-$(CONFIG_ISA_ARCOMPACT) += -mA7
 cflags-$(CONFIG_ISA_ARCV2)     += -mcpu=hs38
+else
+cflags-y                       += $(shell echo $(CONFIG_ARC_MCPU_OVERWRITE))
+endif

 ifdef CONFIG_ARC_CURR_IN_REG
 # For a global register defintion, make sure it gets passed to every file
--
2.21.3

Re: [PATCH 1/3] ARC: allow to overide default mcpu compiler flag

[Vineet Gupta]

On 5/29/20 4:55 AM, Eugeniy Paltsev wrote:
> By default we set -mcpu=xxx compiler flag depending on the CPU ISA
> version. It's good starting point, however that may be not enough
> as for some platforms we may want to use some specific 'mcpu'
> options for better optimization or to workaround HW issues.
> 
> We are going to use this option for HSDK-4xD board support.
> In addition it also allows to awoid patching 'mcpu' in ARC Makefile
> when we building Linux for some non-standard simulation or FPGA-based
> platforms.
> 
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>

Question: So now if I build in buildroot with -mhs38_linux, it will use hard float
(kernel should not use floating point) but the libgcc linked will be different too
and that should be OK ?

I've rewritten the changelog.

  kernel builds set their own default -mcpu for a given ISA build.
  But that gets in the way of "custom" -mcpu flags from propagating
  into kernel build.

  This will also be used in next patches for HSDK-4xD board support which
  uses a different -mcpu to effect dual issue scheduling.

Re: [PATCH 2/3] ARC: ARCv2: support loop buffer (LPB) disabling

[Vineet Gupta]

On 5/29/20 4:55 AM, Eugeniy Paltsev wrote:
> On HS cores, loop buffer (LPB) is programmable in runtime and can
> be optionally disabled.
> 
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>

LGTM.

-Vineet

Re: [PATCH 3/3] ARC: [plat-hsdk-4xd] initial port for HSDK-4xD board

[Vineet Gupta]

+CC Rob H (it seems the CC in patch didn't go thru)

On 5/29/20 4:55 AM, Eugeniy Paltsev wrote:
> This initial port adds support of ARC HS4x/HS4xD Development Kit board with some
> basic features such serial port, USB, SD/MMC, SPI flash, Ethernet and others.
> 
> The HSDK-4xD board has much in common with its predecessor - HSDK board.
> However HSDK-4xD has some differences in comparison with its predecessor:
>  * based on quad core ARC HS48/HS47D processor (instead of quad core ARC HS38)
>  * has ThinkSilicon GPU (instead of Vivante GPU)
>  * has ARC PGU and HDMI output
>  * has separate SDIO controller for WiFi module
>  * has additional timers with clocksource independent from CPU clocksource
>    (required for DVFS)
>  * has performance counters interrupt
>  * other minor stuff
> 
> NOTE:
> HSDK-4xD and HSDK may share significant part of DTS so we can move this common
> part to one .dtsi file (as we have done it in U-boot). However we have quite
> enough out of the tree patches for tweaking HSDK DTS (patches in out
> verification flow, patches for run in simulation, etc...), so I'd prefer to
> keep HSDK DTS untouched. That's why HSDK-4xD DTS is created as an separate file.

I agree we need a different version of DTB for wiring up perf interrupt and gpu
(whether full copy or common parts in a dtsi I don't care). But just curious if
the "other" mods to DTS were temporary "hacks" for various testing things or do
you intend to actually productize/upstream them at some point. I mean you can
alsoways create a local copy for those and point your .config to it, do that is
not a reason to create a new dtb !  I know this is bike shedding...


> Cc: Rob Herring <robh+dt@kernel.org>
> Signed-off-by: Eugeniy Paltsev <Eugeniy.Paltsev@synopsys.com>
> ---
>  arch/arc/boot/dts/hsdk-4xd.dts      | 322 ++++++++++++++++++++++++++++
>  arch/arc/configs/hsdk_4xd_defconfig |  99 +++++++++
>  arch/arc/kernel/devtree.c           |   1 +
>  arch/arc/plat-hsdk/Kconfig          |  24 ++-
>  arch/arc/plat-hsdk/platform.c       |   6 +
>  5 files changed, 451 insertions(+), 1 deletion(-)
>  create mode 100644 arch/arc/boot/dts/hsdk-4xd.dts
>  create mode 100644 arch/arc/configs/hsdk_4xd_defconfig
> 
> diff --git a/arch/arc/boot/dts/hsdk-4xd.dts b/arch/arc/boot/dts/hsdk-4xd.dts
> new file mode 100644
> index 000000000000..2b7f76a01e3e
> --- /dev/null
> +++ b/arch/arc/boot/dts/hsdk-4xd.dts
> @@ -0,0 +1,322 @@
> +// SPDX-License-Identifier: GPL-2.0-only
> +/*
> + * Copyright (C) 2020 Synopsys, Inc. (www.synopsys.com)
> + */
> +
> +/*
> + * Device Tree for ARC HS4x/HS4xD Development Kit
> + */
> +/dts-v1/;
> +
> +#include <dt-bindings/gpio/gpio.h>
> +#include <dt-bindings/reset/snps,hsdk-reset.h>
> +
> +/ {
> +	model = "snps,hsdk-4xd";
> +	compatible = "snps,hsdk-4xd";
> +
> +	#address-cells = <2>;
> +	#size-cells = <2>;
> +
> +	chosen {
> +		bootargs = "earlycon=uart8250,mmio32,0xf0005000,115200n8 console=ttyS0,115200n8 debug print-fatal-signals=1";
> +	};
> +
> +	aliases {
> +		ethernet = &gmac;
> +	};
> +
> +	cpus {
> +		#address-cells = <1>;
> +		#size-cells = <0>;
> +
> +		cpu@0 {
> +			device_type = "cpu";
> +			compatible = "snps,archs48";
> +			reg = <0>;
> +			clocks = <&core_clk>;
> +		};
> +
> +		cpu@1 {
> +			device_type = "cpu";
> +			compatible = "snps,archs48";
> +			reg = <1>;
> +			clocks = <&core_clk>;
> +		};
> +
> +		cpu@2 {
> +			device_type = "cpu";
> +			compatible = "snps,archs48";
> +			reg = <2>;
> +			clocks = <&core_clk>;
> +		};
> +
> +		cpu@3 {
> +			device_type = "cpu";
> +			compatible = "snps,archs48";
> +			reg = <3>;
> +			clocks = <&core_clk>;
> +		};
> +	};
> +
> +	input_clk: input-clk {
> +		#clock-cells = <0>;
> +		compatible = "fixed-clock";
> +		clock-frequency = <33333333>;
> +	};
> +
> +	reg_5v0: regulator-5v0 {
> +		compatible = "regulator-fixed";
> +
> +		regulator-name = "5v0-supply";
> +		regulator-min-microvolt = <5000000>;
> +		regulator-max-microvolt = <5000000>;
> +	};
> +
> +	cpu_intc: cpu-interrupt-controller {
> +		compatible = "snps,archs-intc";
> +		interrupt-controller;
> +		#interrupt-cells = <1>;
> +	};
> +
> +	idu_intc: idu-interrupt-controller {
> +		compatible = "snps,archs-idu-intc";
> +		interrupt-controller;
> +		#interrupt-cells = <1>;
> +		interrupt-parent = <&cpu_intc>;
> +	};
> +
> +	arcpct: pct {
> +		compatible = "snps,archs-pct";
> +		interrupt-parent = <&cpu_intc>;
> +		interrupts = <20>;
> +	};
> +
> +	/* TIMER0 with interrupt for clockevent */
> +	timer {
> +		compatible = "snps,arc-timer";
> +		interrupts = <16>;
> +		interrupt-parent = <&cpu_intc>;
> +		clocks = <&core_clk>;
> +	};
> +
> +	/* 64-bit Global Free Running Counter */
> +	gfrc {
> +		compatible = "snps,archs-timer-gfrc";
> +		clocks = <&core_clk>;
> +	};
> +
> +	soc {
> +		compatible = "simple-bus";
> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		interrupt-parent = <&idu_intc>;
> +
> +		ranges = <0x00000000 0x0 0xf0000000 0x10000000>;
> +
> +		cgu_rst: reset-controller@8a0 {
> +			compatible = "snps,hsdk-reset";
> +			#reset-cells = <1>;
> +			reg = <0x8a0 0x4>, <0xff0 0x4>;
> +		};
> +
> +		core_clk: core-clk@0 {
> +			compatible = "snps,hsdk-core-pll-clock";
> +			reg = <0x00 0x10>, <0x14b8 0x4>;
> +			#clock-cells = <0>;
> +			clocks = <&input_clk>;
> +
> +			/*
> +			 * Set initial core pll output frequency to 1GHz.
> +			 * It will be applied at the core pll driver probing
> +			 * on early boot.
> +			 */
> +			assigned-clocks = <&core_clk>;
> +			assigned-clock-rates = <1000000000>;
> +		};
> +
> +		serial: serial@5000 {
> +			compatible = "snps,dw-apb-uart";
> +			reg = <0x5000 0x100>;
> +			clock-frequency = <33330000>;
> +			interrupts = <6>;
> +			baud = <115200>;
> +			reg-shift = <2>;
> +			reg-io-width = <4>;
> +		};
> +
> +		gmacclk: gmacclk {
> +			compatible = "fixed-clock";
> +			clock-frequency = <400000000>;
> +			#clock-cells = <0>;
> +		};
> +
> +		mmcclk_ciu: mmcclk-ciu {
> +			compatible = "fixed-clock";
> +			/*
> +			 * DW sdio controller has external ciu clock divider
> +			 * controlled via register in SDIO IP. Due to its
> +			 * unexpected default value (it should divide by 1
> +			 * but it divides by 8) SDIO IP uses wrong clock and
> +			 * works unstable (see STAR 9001204800)
> +			 * We switched to the minimum possible value of the
> +			 * divisor (div-by-2) in HSDK platform code.
> +			 * So add temporary fix and change clock frequency
> +			 * to 50000000 Hz until we fix dw sdio driver itself.
> +			 */
> +			clock-frequency = <50000000>;
> +			#clock-cells = <0>;
> +		};
> +
> +		mmcclk_biu: mmcclk-biu {
> +			compatible = "fixed-clock";
> +			clock-frequency = <400000000>;
> +			#clock-cells = <0>;
> +		};
> +
> +		dmac_core_clk: dmac-core-clk {
> +			compatible = "fixed-clock";
> +			clock-frequency = <400000000>;
> +			#clock-cells = <0>;
> +		};
> +
> +		dmac_cfg_clk: dmac-gpu-cfg-clk {
> +			compatible = "fixed-clock";
> +			clock-frequency = <200000000>;
> +			#clock-cells = <0>;
> +		};
> +
> +		gmac: ethernet@8000 {
> +			#interrupt-cells = <1>;
> +			compatible = "snps,dwmac";
> +			reg = <0x8000 0x2000>;
> +			interrupts = <10>;
> +			interrupt-names = "macirq";
> +			phy-mode = "rgmii";
> +			snps,pbl = <32>;
> +			snps,multicast-filter-bins = <256>;
> +			clocks = <&gmacclk>;
> +			clock-names = "stmmaceth";
> +			phy-handle = <&phy0>;
> +			resets = <&cgu_rst HSDK_ETH_RESET>;
> +			reset-names = "stmmaceth";
> +			mac-address = [00 00 00 00 00 00]; /* Filled in by U-Boot */
> +			dma-coherent;
> +
> +			tx-fifo-depth = <4096>;
> +			rx-fifo-depth = <4096>;
> +
> +			mdio {
> +				#address-cells = <1>;
> +				#size-cells = <0>;
> +				compatible = "snps,dwmac-mdio";
> +				phy0: ethernet-phy@0 {
> +					reg = <0>;
> +				};
> +			};
> +		};
> +
> +		ohci@60000 {
> +			compatible = "snps,hsdk-v1.0-ohci", "generic-ohci";
> +			reg = <0x60000 0x100>;
> +			interrupts = <15>;
> +			resets = <&cgu_rst HSDK_USB_RESET>;
> +			dma-coherent;
> +		};
> +
> +		ehci@40000 {
> +			compatible = "snps,hsdk-v1.0-ehci", "generic-ehci";
> +			reg = <0x40000 0x100>;
> +			interrupts = <15>;
> +			resets = <&cgu_rst HSDK_USB_RESET>;
> +			dma-coherent;
> +		};
> +
> +		mmc@a000 {
> +			compatible = "altr,socfpga-dw-mshc";
> +			reg = <0xa000 0x400>;
> +			num-slots = <1>;
> +			fifo-depth = <16>;
> +			card-detect-delay = <200>;
> +			clocks = <&mmcclk_biu>, <&mmcclk_ciu>;
> +			clock-names = "biu", "ciu";
> +			interrupts = <12>;
> +			bus-width = <4>;
> +			dma-coherent;
> +		};
> +
> +		spi0: spi@20000 {
> +			compatible = "snps,dw-apb-ssi";
> +			reg = <0x20000 0x100>;
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +			interrupts = <16>;
> +			num-cs = <2>;
> +			reg-io-width = <4>;
> +			clocks = <&input_clk>;
> +			cs-gpios = <&creg_gpio 0 GPIO_ACTIVE_LOW>,
> +				   <&creg_gpio 1 GPIO_ACTIVE_LOW>;
> +
> +			spi-flash@0 {
> +				compatible = "sst26wf016b", "jedec,spi-nor";
> +				reg = <0>;
> +				#address-cells = <1>;
> +				#size-cells = <1>;
> +				spi-max-frequency = <4000000>;
> +			};
> +
> +			adc@1 {
> +				compatible = "ti,adc108s102";
> +				reg = <1>;
> +				vref-supply = <&reg_5v0>;
> +				spi-max-frequency = <1000000>;
> +			};
> +		};
> +
> +		creg_gpio: gpio@14b0 {
> +			compatible = "snps,creg-gpio-hsdk";
> +			reg = <0x14b0 0x4>;
> +			gpio-controller;
> +			#gpio-cells = <2>;
> +			ngpios = <2>;
> +		};
> +
> +		gpio: gpio@3000 {
> +			compatible = "snps,dw-apb-gpio";
> +			reg = <0x3000 0x20>;
> +			#address-cells = <1>;
> +			#size-cells = <0>;
> +
> +			gpio_port_a: gpio-controller@0 {
> +				compatible = "snps,dw-apb-gpio-port";
> +				gpio-controller;
> +				#gpio-cells = <2>;
> +				snps,nr-gpios = <24>;
> +				reg = <0>;
> +			};
> +		};
> +
> +		dmac: dmac@80000 {
> +			compatible = "snps,axi-dma-1.01a";
> +			reg = <0x80000 0x400>;
> +			interrupts = <27>;
> +			clocks = <&dmac_core_clk>, <&dmac_cfg_clk>;
> +			clock-names = "core-clk", "cfgr-clk";
> +
> +			dma-channels = <4>;
> +			snps,dma-masters = <2>;
> +			snps,data-width = <3>;
> +			snps,block-size = <4096 4096 4096 4096>;
> +			snps,priority = <0 1 2 3>;
> +			snps,axi-max-burst-len = <16>;
> +		};
> +	};
> +
> +	memory@80000000 {
> +		#address-cells = <2>;
> +		#size-cells = <2>;
> +		device_type = "memory";
> +		reg = <0x0 0x80000000 0x0 0x40000000>;  /* 1 GB lowmem */
> +		/*     0x1 0x00000000 0x0 0x40000000>;     1 GB highmem */
> +	};
> +};
> diff --git a/arch/arc/configs/hsdk_4xd_defconfig b/arch/arc/configs/hsdk_4xd_defconfig
> new file mode 100644
> index 000000000000..bf78f745a0f6
> --- /dev/null
> +++ b/arch/arc/configs/hsdk_4xd_defconfig
> @@ -0,0 +1,99 @@
> +CONFIG_SYSVIPC=y
> +# CONFIG_CROSS_MEMORY_ATTACH is not set
> +CONFIG_NO_HZ_IDLE=y
> +CONFIG_HIGH_RES_TIMERS=y
> +CONFIG_PREEMPT=y
> +CONFIG_IKCONFIG=y
> +CONFIG_IKCONFIG_PROC=y
> +CONFIG_NAMESPACES=y
> +# CONFIG_UTS_NS is not set
> +# CONFIG_PID_NS is not set
> +CONFIG_BLK_DEV_INITRD=y
> +CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3=y
> +CONFIG_EMBEDDED=y
> +CONFIG_PERF_EVENTS=y
> +# CONFIG_VM_EVENT_COUNTERS is not set
> +# CONFIG_COMPAT_BRK is not set
> +CONFIG_SLAB=y
> +CONFIG_ARC_SOC_HSDK=y
> +CONFIG_ARC_BOARD_HSDK_4XD=y
> +CONFIG_SMP=y
> +CONFIG_ARC_TUNE_MCPU="-mcpu=hs4x_rel31"
> +CONFIG_ARC_DSP_KERNEL=y
> +CONFIG_LINUX_LINK_BASE=0x90000000
> +CONFIG_LINUX_RAM_BASE=0x80000000
> +CONFIG_ARC_BUILTIN_DTB_NAME="hsdk-4xd"
> +CONFIG_JUMP_LABEL=y
> +CONFIG_MODULES=y
> +CONFIG_MODULE_UNLOAD=y
> +# CONFIG_COMPACTION is not set
> +CONFIG_NET=y
> +CONFIG_PACKET=y
> +CONFIG_UNIX=y
> +CONFIG_INET=y
> +CONFIG_DEVTMPFS=y
> +# CONFIG_STANDALONE is not set
> +# CONFIG_PREVENT_FIRMWARE_BUILD is not set
> +CONFIG_MTD=y
> +CONFIG_MTD_SPI_NOR=y
> +CONFIG_BLK_DEV_RAM=y
> +CONFIG_SCSI=y
> +CONFIG_BLK_DEV_SD=y
> +CONFIG_NETDEVICES=y
> +CONFIG_STMMAC_ETH=y
> +CONFIG_MICREL_PHY=y
> +CONFIG_INPUT_EVDEV=y
> +# CONFIG_INPUT_KEYBOARD is not set
> +# CONFIG_INPUT_MOUSE is not set
> +# CONFIG_SERIO is not set
> +# CONFIG_LEGACY_PTYS is not set
> +CONFIG_SERIAL_8250=y
> +CONFIG_SERIAL_8250_CONSOLE=y
> +CONFIG_SERIAL_8250_DW=y
> +CONFIG_SERIAL_OF_PLATFORM=y
> +# CONFIG_HW_RANDOM is not set
> +CONFIG_SPI=y
> +CONFIG_SPI_DESIGNWARE=y
> +CONFIG_SPI_DW_MMIO=y
> +CONFIG_GPIOLIB=y
> +CONFIG_GPIO_SYSFS=y
> +CONFIG_GPIO_DWAPB=y
> +CONFIG_GPIO_SNPS_CREG=y
> +# CONFIG_HWMON is not set
> +CONFIG_THERMAL=y
> +CONFIG_REGULATOR=y
> +CONFIG_REGULATOR_FIXED_VOLTAGE=y
> +CONFIG_DRM=y
> +# CONFIG_DRM_FBDEV_EMULATION is not set
> +CONFIG_DRM_UDL=y
> +CONFIG_FB=y
> +CONFIG_FRAMEBUFFER_CONSOLE=y
> +CONFIG_USB=y
> +CONFIG_USB_EHCI_HCD=y
> +CONFIG_USB_EHCI_HCD_PLATFORM=y
> +CONFIG_USB_OHCI_HCD=y
> +CONFIG_USB_OHCI_HCD_PLATFORM=y
> +CONFIG_USB_STORAGE=y
> +CONFIG_MMC=y
> +CONFIG_MMC_SDHCI=y
> +CONFIG_MMC_SDHCI_PLTFM=y
> +CONFIG_MMC_DW=y
> +CONFIG_DMADEVICES=y
> +CONFIG_DW_AXI_DMAC=y
> +CONFIG_IIO=y
> +CONFIG_TI_ADC108S102=y
> +CONFIG_EXT3_FS=y
> +CONFIG_VFAT_FS=y
> +CONFIG_TMPFS=y
> +CONFIG_NFS_FS=y
> +CONFIG_NFS_V3_ACL=y
> +CONFIG_NLS_CODEPAGE_437=y
> +CONFIG_NLS_ISO8859_1=y
> +CONFIG_CRYPTO_ECHAINIV=y
> +# CONFIG_ENABLE_MUST_CHECK is not set
> +CONFIG_STRIP_ASM_SYMS=y
> +CONFIG_SOFTLOCKUP_DETECTOR=y
> +CONFIG_DEFAULT_HUNG_TASK_TIMEOUT=10
> +# CONFIG_SCHED_DEBUG is not set
> +# CONFIG_DEBUG_PREEMPT is not set
> +# CONFIG_FTRACE is not set
> diff --git a/arch/arc/kernel/devtree.c b/arch/arc/kernel/devtree.c
> index fa86d13df5ed..81f881af7356 100644
> --- a/arch/arc/kernel/devtree.c
> +++ b/arch/arc/kernel/devtree.c
> @@ -27,6 +27,7 @@ static void __init arc_set_early_base_baud(unsigned long dt_root)
>  	if (of_flat_dt_is_compatible(dt_root, "abilis,arc-tb10x"))
>  		arc_base_baud = 166666666;	/* Fixed 166.6MHz clk (TB10x) */
>  	else if (of_flat_dt_is_compatible(dt_root, "snps,arc-sdp") ||
> +		 of_flat_dt_is_compatible(dt_root, "snps,hsdk-4xd") ||
>  		 of_flat_dt_is_compatible(dt_root, "snps,hsdk"))
>  		arc_base_baud = 33333333;	/* Fixed 33MHz clk (AXS10x & HSDK) */
>  	else if (of_flat_dt_is_compatible(dt_root, "ezchip,arc-nps"))
> diff --git a/arch/arc/plat-hsdk/Kconfig b/arch/arc/plat-hsdk/Kconfig
> index ce8101834518..3bf80eceebae 100644
> --- a/arch/arc/plat-hsdk/Kconfig
> +++ b/arch/arc/plat-hsdk/Kconfig
> @@ -3,10 +3,32 @@
>  #
>  
>  menuconfig ARC_SOC_HSDK
> -	bool "ARC HS Development Kit SOC"
> +	bool "ARC HSDK or HSDK-4xD SoCs"
>  	depends on ISA_ARCV2
>  	select ARC_HAS_ACCL_REGS
>  	select ARC_IRQ_NO_AUTOSAVE
>  	select CLK_HSDK
>  	select RESET_HSDK
>  	select HAVE_PCI
> +
> +menu "HSDK / HSDK-4xD options"
> +	visible if ARC_SOC_HSDK
> +
> +choice
> +	prompt "HSDK board type"
> +
> +config ARC_BOARD_HSDK
> +	bool "ARC HS Development Kit"
> +	help
> +	  ARC HS Development Kit based on quad core ARC HS38 processor
> +
> +config ARC_BOARD_HSDK_4XD
> +	bool "ARC HS4x/HS4xD Development Kit"
> +	select ARC_LPB_DISABLE
> +	help
> +	  ARC HS4x/HS4xD Development Kit based on quad core ARC HS48/HS47D
> +	  processor
> +
> +endchoice

You also need to update existing hsdk.dts to add CONFIG_ARC_BOARD_HSDK

> +
> +endmenu
> diff --git a/arch/arc/plat-hsdk/platform.c b/arch/arc/plat-hsdk/platform.c
> index 0b961a2a10b8..74e2508cfd1e 100644
> --- a/arch/arc/plat-hsdk/platform.c
> +++ b/arch/arc/plat-hsdk/platform.c
> @@ -331,7 +331,13 @@ static void __init hsdk_init_early(void)
>  	hsdk_enable_gpio_intc_wire();
>  }
>  
> +/*
> + * As we aren't going to run HSDK-4xD Linux image on HSDK and vise versa let's
> + * don't add additional machine entry but instead add new compatible to existing one and
> + * resolve all differences in compile time with #ifdef's.
> + */
>  static const char *hsdk_compat[] __initconst = {
> +	"snps,hsdk-4xd",
>  	"snps,hsdk",
>  	NULL,
>  };
> 

I don't see how the comment above relates to change. Infact the change *does*
potentially allow one image to run on other (with say old DTB).

The change itself is good ether way as  ARC_SOC_HSDK ties both tof them together
and we don't need a different machine array.

Since I don't have the new board yet is there a technical reason we can't run the
image for old board on new one (assume I don't care about the GPU and ignore perf
interrupt).

-Vineet