MSCC: add board support for the Ocelots based evaluation boards

Adding the support for 2 boards sharing common code for Ocelot chip:
PCB120 and PCB123

Signed-off-by: Gregory CLEMENT <gregory.clement@bootlin.com>
diff --git a/board/mscc/ocelot/ocelot.c b/board/mscc/ocelot/ocelot.c
new file mode 100644
index 0000000..d521a61
--- /dev/null
+++ b/board/mscc/ocelot/ocelot.c
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
+/*
+ * Copyright (c) 2018 Microsemi Corporation
+ */
+
+#include <common.h>
+#include <asm/io.h>
+#include <asm/addrspace.h>
+#include <asm/types.h>
+#include <environment.h>
+#include <spi.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+#define MSCC_GPIO_ALT0		0x54
+#define MSCC_GPIO_ALT1		0x58
+
+void external_cs_manage(struct udevice *dev, bool enable)
+{
+	u32 cs = spi_chip_select(dev);
+	/* IF_SI0_OWNER, select the owner of the SI interface
+	 * Encoding: 0: SI Slave
+	 *           1: SI Boot Master
+	 *           2: SI Master Controller
+	 */
+	if (!enable) {
+		writel(ICPU_SW_MODE_SW_PIN_CTRL_MODE |
+		       ICPU_SW_MODE_SW_SPI_CS(BIT(cs)), BASE_CFG + ICPU_SW_MODE);
+		clrsetbits_le32(BASE_CFG + ICPU_GENERAL_CTRL,
+				ICPU_GENERAL_CTRL_IF_SI_OWNER_M,
+				ICPU_GENERAL_CTRL_IF_SI_OWNER(2));
+	} else {
+		writel(0, BASE_CFG + ICPU_SW_MODE);
+		clrsetbits_le32(BASE_CFG + ICPU_GENERAL_CTRL,
+				ICPU_GENERAL_CTRL_IF_SI_OWNER_M,
+				ICPU_GENERAL_CTRL_IF_SI_OWNER(1));
+	}
+}
+
+void board_debug_uart_init(void)
+{
+	/* too early for the pinctrl driver, so configure the UART pins here */
+	setbits_le32(BASE_DEVCPU_GCB + MSCC_GPIO_ALT0, BIT(6) | BIT(7));
+	clrbits_le32(BASE_DEVCPU_GCB + MSCC_GPIO_ALT1, BIT(6) | BIT(7));
+}
+
+int board_early_init_r(void)
+{
+	/* Prepare SPI controller to be used in master mode */
+	writel(0, BASE_CFG + ICPU_SW_MODE);
+	clrsetbits_le32(BASE_CFG + ICPU_GENERAL_CTRL,
+			ICPU_GENERAL_CTRL_IF_SI_OWNER_M,
+			ICPU_GENERAL_CTRL_IF_SI_OWNER(2));
+
+	/* Address of boot parameters */
+	gd->bd->bi_boot_params = CONFIG_SYS_SDRAM_BASE;
+	return 0;
+}