ARC: Add support for EM Development Kit board

Synopsys DesignWare ARC EM Development Kit (ARC EMDK) is
an FPGA-based development platform from Synopsys aimed to speed-up
development of software for ARC EM cores and entire subsystems based on
ARC EM like Data Fusion, Secure and Sensor & Control subsystems.

U-Boot is supposed to be used as a primary bootloader on EMDK allowing
users to easily load and start their application from micro-SD card.

Signed-off-by: Alexey Brodkin <abrodkin@synopsys.com>

arch/arc/Kconfig

@@ -150,6 +150,10 @@ config TARGET_AXS101
 config TARGET_AXS103
 	bool "Support Synopsys Designware SDP board AXS103"
 
+config TARGET_EMDK
+	bool "Synopsys EM Development kit"
+	select CPU_ARCEM6
+
 config TARGET_HSDK
 	bool "Support Synpsys HS DevelopmentKit board"
 
@@ -158,6 +162,7 @@ endchoice
 source "board/abilis/tb100/Kconfig"
 source "board/synopsys/Kconfig"
 source "board/synopsys/axs10x/Kconfig"
+source "board/synopsys/emdk/Kconfig"
 source "board/synopsys/hsdk/Kconfig"
 
 endmenu

arch/arc/dts/Makefile

@@ -4,6 +4,7 @@ dtb-$(CONFIG_TARGET_AXS101) +=  axs101.dtb
 dtb-$(CONFIG_TARGET_AXS103) +=  axs103.dtb
 dtb-$(CONFIG_TARGET_NSIM) +=  nsim.dtb
 dtb-$(CONFIG_TARGET_TB100) +=  abilis_tb100.dtb
+dtb-$(CONFIG_TARGET_EMDK) +=  emdk.dtb
 dtb-$(CONFIG_TARGET_HSDK) +=  hsdk.dtb
 
 targets += $(dtb-y)

arch/arc/dts/emdk.dts

@@ -0,0 +1,33 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Synopsys, Inc. All rights reserved.
+ */
+/dts-v1/;
+
+#include "skeleton.dtsi"
+
+/ {
+	#address-cells = <1>;
+	#size-cells = <1>;
+
+	aliases {
+		console = &uart0;
+	};
+
+	cpu_card {
+		core_clk: core_clk {
+			#clock-cells = <0>;
+			compatible = "fixed-clock";
+			clock-frequency = <40000000>;
+			u-boot,dm-pre-reloc;
+		};
+	};
+
+	uart0: serial0@f0004000 {
+		compatible = "snps,dw-apb-uart";
+		clock-frequency = <100000000>;
+		reg = <0xf0004000 0x1000>;
+		reg-shift = <2>;
+		reg-io-width = <4>;
+	};
+};

board/synopsys/emdk/Kconfig

@@ -0,0 +1,12 @@
+if TARGET_EMDK
+
+config SYS_BOARD
+	default "emdk"
+
+config SYS_VENDOR
+	default "synopsys"
+
+config SYS_CONFIG_NAME
+	default "emdk"
+
+endif

board/synopsys/emdk/MAINTAINERS

@@ -0,0 +1,5 @@
+EM DEVELOPMENT KIT BOARD
+M:	Alexey Brodkin <abrodkin@synopsys.com>
+S:	Maintained
+F:	board/synopsys/emdk/
+F:	configs/emdk_defconfig

board/synopsys/emdk/Makefile

@@ -0,0 +1,7 @@
+#
+# Copyright (C) 2018 Synopsys, Inc. All rights reserved.
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y	+= emdk.o

board/synopsys/emdk/emdk.c

@@ -0,0 +1,92 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2018 Synopsys, Inc. All rights reserved.
+ */
+
+#include <common.h>
+#include <dwmmc.h>
+#include <malloc.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define ARC_PERIPHERAL_BASE	0xF0000000
+#define SDIO_BASE		(ARC_PERIPHERAL_BASE + 0x10000)
+
+int board_mmc_init(bd_t *bis)
+{
+	struct dwmci_host *host = NULL;
+
+	host = malloc(sizeof(struct dwmci_host));
+	if (!host) {
+		printf("dwmci_host malloc fail!\n");
+		return 1;
+	}
+
+	memset(host, 0, sizeof(struct dwmci_host));
+	host->name = "Synopsys Mobile storage";
+	host->ioaddr = (void *)SDIO_BASE;
+	host->buswidth = 4;
+	host->dev_index = 0;
+	host->bus_hz = 50000000;
+
+	add_dwmci(host, host->bus_hz / 2, 400000);
+
+	return 0;
+}
+
+#define CREG_BASE		0xF0001000
+#define CREG_BOOT_OFFSET	0
+#define CREG_BOOT_WP_OFFSET	8
+
+#define CGU_BASE		0xF0000000
+#define CGU_IP_SW_RESET		0x0FF0
+
+void reset_cpu(ulong addr)
+{
+	writel(1, (u32 *)(CGU_BASE + CGU_IP_SW_RESET));
+	while (1)
+		; /* loop forever till reset */
+}
+
+static int do_emdk_rom(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
+{
+	u32 creg_boot = readl((u32 *)(CREG_BASE + CREG_BOOT_OFFSET));
+
+	if (!strcmp(argv[1], "unlock"))
+		creg_boot &= ~BIT(CREG_BOOT_WP_OFFSET);
+	else if (!strcmp(argv[1], "lock"))
+		creg_boot |= BIT(CREG_BOOT_WP_OFFSET);
+	else
+		return CMD_RET_USAGE;
+
+	writel(creg_boot, (u32 *)(CREG_BASE + CREG_BOOT_OFFSET));
+
+	return CMD_RET_SUCCESS;
+}
+
+cmd_tbl_t cmd_emdk[] = {
+	U_BOOT_CMD_MKENT(rom, 2, 0, do_emdk_rom, "", ""),
+};
+
+static int do_emdk(cmd_tbl_t *cmdtp, int flag, int argc, char *const argv[])
+{
+	cmd_tbl_t *c;
+
+	c = find_cmd_tbl(argv[1], cmd_emdk, ARRAY_SIZE(cmd_emdk));
+
+	/* Strip off leading 'emdk' command */
+	argc--;
+	argv++;
+
+	if (c == NULL || argc > c->maxargs)
+		return CMD_RET_USAGE;
+
+	return c->cmd(cmdtp, flag, argc, argv);
+}
+
+U_BOOT_CMD(
+	emdk, CONFIG_SYS_MAXARGS, 0, do_emdk,
+	"Synopsys EMDK specific commands",
+	"rom unlock - Unlock non-volatile memory for writing\n"
+	"emdk rom lock - Lock non-volatile memory to prevent writing\n"
+);

configs/emdk_defconfig

@@ -0,0 +1,31 @@
+CONFIG_ARC=y
+CONFIG_ISA_ARCV2=y
+CONFIG_CPU_ARCEM6=y
+CONFIG_TARGET_EMDK=y
+CONFIG_SYS_TEXT_BASE=0x00000000
+CONFIG_SYS_CLK_FREQ=40000000
+CONFIG_DEFAULT_DEVICE_TREE="emdk"
+# CONFIG_ARCH_FIXUP_FDT_MEMORY is not set
+CONFIG_VERSION_VARIABLE=y
+CONFIG_HUSH_PARSER=y
+CONFIG_SYS_PROMPT="emdk# "
+# CONFIG_CMD_BOOTD is not set
+# CONFIG_CMD_ELF is not set
+# CONFIG_CMD_XIMG is not set
+CONFIG_CMD_MMC=y
+CONFIG_CMD_CACHE=y
+CONFIG_CMD_FAT=y
+CONFIG_OF_CONTROL=y
+CONFIG_OF_EMBED=y
+CONFIG_ENV_IS_IN_FAT=y
+CONFIG_ENV_FAT_INTERFACE="mmc"
+CONFIG_ENV_FAT_DEVICE_AND_PART="0:1"
+# CONFIG_NET is not set
+CONFIG_DM=y
+CONFIG_MMC=y
+CONFIG_MMC_DW=y
+CONFIG_DM_SERIAL=y
+CONFIG_SYS_NS16550=y
+CONFIG_FS_FAT_MAX_CLUSTSIZE=4096
+CONFIG_USE_PRIVATE_LIBGCC=y
+CONFIG_PANIC_HANG=y

include/configs/emdk.h

@@ -0,0 +1,40 @@
+/* SPDX-License-Identifier: GPL-2.0+ */
+/*
+ * Copyright (C) 2018 Synopsys, Inc. All rights reserved.
+ */
+
+#ifndef _CONFIG_EMDK_H_
+#define _CONFIG_EMDK_H_
+
+#include <linux/sizes.h>
+
+#define CONFIG_SYS_MONITOR_BASE		CONFIG_SYS_TEXT_BASE
+
+#define CONFIG_SYS_SDRAM_BASE		0x10000000
+#define CONFIG_SYS_SDRAM_SIZE		SZ_8M
+
+#define CONFIG_SYS_INIT_SP_ADDR		(CONFIG_SYS_SDRAM_BASE + SZ_1M)
+
+#define CONFIG_SYS_MALLOC_LEN		SZ_64K
+#define CONFIG_SYS_LOAD_ADDR		CONFIG_SYS_SDRAM_BASE
+
+/* Required by DW MMC driver */
+#define CONFIG_BOUNCE_BUFFER
+
+/*
+ * Environment
+ */
+#define CONFIG_ENV_SIZE			SZ_4K
+#define CONFIG_BOOTFILE			"app.bin"
+#define CONFIG_LOADADDR			CONFIG_SYS_LOAD_ADDR
+
+#define CONFIG_EXTRA_ENV_SETTINGS \
+	"upgrade_image=u-boot.bin\0" \
+	"upgrade=emdk rom unlock && " \
+		"fatload mmc 0 ${loadaddr} ${upgrade_image} && " \
+		"cp.b ${loadaddr} 0 ${filesize} && " \
+		"dcache flush && " \
+		"emdk rom lock\0"
+
+#endif /* _CONFIG_EMDK_H_ */
+