arm: Add support for LEGO MINDSTORMS EV3

This is based on the davinci da850evm. It can boot from either the
on-board 16MB flash or from a microSD card. It also reads board
information from an I2C EEPROM.

The EV3 itself initally boots from write-protected EEPROM, so no
u-boot SPL is needed.

Signed-off-by: David Lechner <david@lechnology.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

5 files changed, 236 insertions, 0 deletions

diff --git a/board/lego/ev3/Kconfig b/board/lego/ev3/Kconfig
new file mode 100644
index 0000000000..14b3f0c1cf
--- /dev/null
+++ b/board/lego/ev3/Kconfig
@@ -0,0 +1,12 @@
+if TARGET_LEGOEV3
+
+config SYS_BOARD
+	default "ev3"
+
+config SYS_VENDOR
+	default "lego"
+
+config SYS_CONFIG_NAME
+	default "legoev3"
+
+endif
diff --git a/board/lego/ev3/MAINTAINERS b/board/lego/ev3/MAINTAINERS
new file mode 100644
index 0000000000..11b3261609
--- /dev/null
+++ b/board/lego/ev3/MAINTAINERS
@@ -0,0 +1,6 @@
+LEGOEV3 BOARD
+M:	David Lechner <david@lechnology.com>
+S:	Maintained
+F:	board/lego/ev3/
+F:	include/configs/legoev3.h
+F:	configs/legoev3_defconfig
diff --git a/board/lego/ev3/Makefile b/board/lego/ev3/Makefile
new file mode 100644
index 0000000000..f3e717ab66
--- /dev/null
+++ b/board/lego/ev3/Makefile
@@ -0,0 +1,10 @@
+#
+# (C) Copyright 2000, 2001, 2002
+# Wolfgang Denk, DENX Software Engineering, wd@denx.de.
+#
+# Copyright (C) 2007 Sergey Kubushyn <ksi@koi8.net>
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+
+obj-y	+= legoev3.o
diff --git a/board/lego/ev3/README b/board/lego/ev3/README
new file mode 100644
index 0000000000..1a50ca9d03
--- /dev/null
+++ b/board/lego/ev3/README
@@ -0,0 +1,32 @@
+Summary
+=======
+
+LEGO MINDSTORMS EV3 is a toy robot produced by the LEGO Group. It is based
+on the davinci da850 evm. The EV3 has a 16MB spi flash and a SDHC microSD card
+reader.
+
+Booting
+=======
+
+The EV3 contains a bootloader in EEPROM that loads u-boot.bin from address 0x0
+of the spi flash memory. Using the default configuration, u-boot will check to
+see if there is a boot.scr file on the first FAT partition of the mmc. If there
+is, it will run the script and boot the kernel from the uImage file also in
+the FAT partition. Otherwise, it will load a kernel and rootfs from the flash.
+The kernel must be stored at address 0x50000 on the flash and have a maximum
+size of 3MiB. The rootfs must be a squasfs image and stored at 0x350000 in the
+flash and have a maximum size of 9.3MiB. The flash starting at 0xCB0000 is
+reserved for user data.
+
+Writing image to flash
+======================
+
+The EEPROM contains a program for uploading an image file to the flash memory.
+The program is started by holding down the right button on the EV3 when powering
+it on. You can also `run fwupdateboot` in the u-boot shell to reboot into this
+mode. The image can then be uploaded using the official LEGO MINDSTORMS EV3
+software or a 3rd party program capable of uploading a firmware file.
+
+If you are booting from the microSD card, it is enough to just write uboot.bin
+to the flash. If you are not using a microSD card, you will need to create an
+image file using the layout described above.
diff --git a/board/lego/ev3/legoev3.c b/board/lego/ev3/legoev3.c
new file mode 100644
index 0000000000..a791b97f8f
--- /dev/null
+++ b/board/lego/ev3/legoev3.c
@@ -0,0 +1,176 @@
+/*
+ * Copyright (C) 2016 David Lechner <david@lechnology.com>
+ *
+ * Based on da850evm.c
+ *
+ * Copyright (C) 2010 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * Based on da830evm.c. Original Copyrights follow:
+ *
+ * Copyright (C) 2009 Nick Thompson, GE Fanuc, Ltd. <nick.thompson@gefanuc.com>
+ * Copyright (C) 2007 Sergey Kubushyn <ksi@koi8.net>
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <i2c.h>
+#include <net.h>
+#include <netdev.h>
+#include <spi.h>
+#include <spi_flash.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/pinmux_defs.h>
+#include <asm/io.h>
+#include <asm/arch/davinci_misc.h>
+#include <asm/errno.h>
+#include <hwconfig.h>
+
+#ifdef CONFIG_DAVINCI_MMC
+#include <mmc.h>
+#include <asm/arch/sdmmc_defs.h>
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+u8 board_rev;
+
+#define EEPROM_I2C_ADDR		0x50
+#define EEPROM_REV_OFFSET	0x3F00
+#define EEPROM_MAC_OFFSET	0x3F06
+
+#ifdef CONFIG_DAVINCI_MMC
+static struct davinci_mmc mmc_sd0 = {
+	.reg_base = (struct davinci_mmc_regs *)DAVINCI_MMC_SD0_BASE,
+	.host_caps = MMC_MODE_4BIT,     /* DA850 supports only 4-bit SD/MMC */
+	.voltages = MMC_VDD_32_33 | MMC_VDD_33_34,
+	.version = MMC_CTLR_VERSION_2,
+};
+
+int board_mmc_init(bd_t *bis)
+{
+	mmc_sd0.input_clk = clk_get(DAVINCI_MMCSD_CLKID);
+
+	/* Add slot-0 to mmc subsystem */
+	return davinci_mmc_init(bis, &mmc_sd0);
+}
+#endif
+
+const struct pinmux_resource pinmuxes[] = {
+	PINMUX_ITEM(spi0_pins_base),
+	PINMUX_ITEM(spi0_pins_scs0),
+	PINMUX_ITEM(uart1_pins_txrx),
+	PINMUX_ITEM(i2c0_pins),
+	PINMUX_ITEM(mmc0_pins),
+};
+
+const int pinmuxes_size = ARRAY_SIZE(pinmuxes);
+
+const struct lpsc_resource lpsc[] = {
+	{ DAVINCI_LPSC_SPI0 },	/* Serial Flash */
+	{ DAVINCI_LPSC_UART1 },	/* console */
+	{ DAVINCI_LPSC_MMC_SD },
+};
+
+const int lpsc_size = ARRAY_SIZE(lpsc);
+
+u32 get_board_rev(void)
+{
+	u8 buf[2];
+
+	if (!board_rev) {
+		if (i2c_read(EEPROM_I2C_ADDR, EEPROM_REV_OFFSET, 2, buf, 2)) {
+			printf("\nBoard revision read failed!\n");
+		} else {
+			/*
+			 * Board rev 3 has MAC address at EEPROM_REV_OFFSET.
+			 * Other revisions have checksum at EEPROM_REV_OFFSET+1
+			 * to detect this.
+			 */
+			if ((buf[0] ^ buf[1]) == 0xFF)
+				board_rev = buf[0];
+			else
+				board_rev = 3;
+		}
+	}
+
+	return board_rev;
+}
+
+/*
+ * The Bluetooth MAC address serves as the board serial number.
+ */
+void get_board_serial(struct tag_serialnr *serialnr)
+{
+	u32 offset;
+	u8 buf[6];
+
+	if (!board_rev)
+		board_rev = get_board_rev();
+
+	/* Board rev 3 has MAC address where rev should be */
+	offset = (board_rev == 3) ? EEPROM_REV_OFFSET : EEPROM_MAC_OFFSET;
+
+	if (i2c_read(EEPROM_I2C_ADDR, offset, 2, buf, 6)) {
+		printf("\nBoard serial read failed!\n");
+	} else {
+		u8 *nr;
+
+		nr = (u8 *)&serialnr->low;
+		nr[0] = buf[5];
+		nr[1] = buf[4];
+		nr[2] = buf[3];
+		nr[3] = buf[2];
+		nr = (u8 *)&serialnr->high;
+		nr[0] = buf[1];
+		nr[1] = buf[0];
+		nr[2] = 0;
+		nr[3] = 0;
+	}
+}
+
+int board_early_init_f(void)
+{
+	/*
+	 * Power on required peripherals
+	 * ARM does not have access by default to PSC0 and PSC1
+	 * assuming here that the DSP bootloader has set the IOPU
+	 * such that PSC access is available to ARM
+	 */
+	if (da8xx_configure_lpsc_items(lpsc, ARRAY_SIZE(lpsc)))
+		return 1;
+
+	return 0;
+}
+
+int board_init(void)
+{
+#ifndef CONFIG_USE_IRQ
+	irq_init();
+#endif
+
+	/* arch number of the board */
+	/* LEGO didn't register for a unique number and uses da850evm */
+	gd->bd->bi_arch_number = MACH_TYPE_DAVINCI_DA850_EVM;
+
+	/* address of boot parameters */
+	gd->bd->bi_boot_params = LINUX_BOOT_PARAM_ADDR;
+
+	/* setup the SUSPSRC for ARM to control emulation suspend */
+	writel(readl(&davinci_syscfg_regs->suspsrc) &
+	       ~(DAVINCI_SYSCFG_SUSPSRC_EMAC | DAVINCI_SYSCFG_SUSPSRC_I2C |
+		 DAVINCI_SYSCFG_SUSPSRC_SPI0 | DAVINCI_SYSCFG_SUSPSRC_TIMER0 |
+		 DAVINCI_SYSCFG_SUSPSRC_UART1),
+	       &davinci_syscfg_regs->suspsrc);
+
+	/* configure pinmux settings */
+	if (davinci_configure_pin_mux_items(pinmuxes, ARRAY_SIZE(pinmuxes)))
+		return 1;
+
+	/* enable the console UART */
+	writel((DAVINCI_UART_PWREMU_MGMT_FREE | DAVINCI_UART_PWREMU_MGMT_URRST |
+		DAVINCI_UART_PWREMU_MGMT_UTRST),
+	       &davinci_uart1_ctrl_regs->pwremu_mgmt);
+
+	return 0;
+}