arm: mach-k3: am625: Provide a way to obtain boot device for non SPLs

Introduce get_boot_device() to obtain the booting device. Make it also
available for non SPL builds so u-boot can also know the device it is
booting from.

Signed-off-by: Wadim Egorov <w.egorov@phytec.de>
diff --git a/arch/arm/mach-k3/am62x/boot.c b/arch/arm/mach-k3/am62x/boot.c
new file mode 100644
index 0000000..132b42f
--- /dev/null
+++ b/arch/arm/mach-k3/am62x/boot.c
@@ -0,0 +1,103 @@
+// SPDX-License-Identifier: GPL-2.0+
+#include <asm/io.h>
+#include <asm/arch/hardware.h>
+#include <asm/arch/am62_spl.h>
+
+static u32 __get_backup_bootmedia(u32 devstat)
+{
+	u32 bkup_bootmode = (devstat & MAIN_DEVSTAT_BACKUP_BOOTMODE_MASK) >>
+				MAIN_DEVSTAT_BACKUP_BOOTMODE_SHIFT;
+	u32 bkup_bootmode_cfg =
+			(devstat & MAIN_DEVSTAT_BACKUP_BOOTMODE_CFG_MASK) >>
+				MAIN_DEVSTAT_BACKUP_BOOTMODE_CFG_SHIFT;
+
+	switch (bkup_bootmode) {
+	case BACKUP_BOOT_DEVICE_UART:
+		return BOOT_DEVICE_UART;
+
+	case BACKUP_BOOT_DEVICE_USB:
+		return BOOT_DEVICE_USB;
+
+	case BACKUP_BOOT_DEVICE_ETHERNET:
+		return BOOT_DEVICE_ETHERNET;
+
+	case BACKUP_BOOT_DEVICE_MMC:
+		if (bkup_bootmode_cfg)
+			return BOOT_DEVICE_MMC2;
+		return BOOT_DEVICE_MMC1;
+
+	case BACKUP_BOOT_DEVICE_SPI:
+		return BOOT_DEVICE_SPI;
+
+	case BACKUP_BOOT_DEVICE_I2C:
+		return BOOT_DEVICE_I2C;
+
+	case BACKUP_BOOT_DEVICE_DFU:
+		if (bkup_bootmode_cfg & MAIN_DEVSTAT_BACKUP_USB_MODE_MASK)
+			return BOOT_DEVICE_USB;
+		return BOOT_DEVICE_DFU;
+	};
+
+	return BOOT_DEVICE_RAM;
+}
+
+static u32 __get_primary_bootmedia(u32 devstat)
+{
+	u32 bootmode = (devstat & MAIN_DEVSTAT_PRIMARY_BOOTMODE_MASK) >>
+				MAIN_DEVSTAT_PRIMARY_BOOTMODE_SHIFT;
+	u32 bootmode_cfg = (devstat & MAIN_DEVSTAT_PRIMARY_BOOTMODE_CFG_MASK) >>
+				MAIN_DEVSTAT_PRIMARY_BOOTMODE_CFG_SHIFT;
+
+	switch (bootmode) {
+	case BOOT_DEVICE_OSPI:
+		fallthrough;
+	case BOOT_DEVICE_QSPI:
+		fallthrough;
+	case BOOT_DEVICE_XSPI:
+		fallthrough;
+	case BOOT_DEVICE_SPI:
+		return BOOT_DEVICE_SPI;
+
+	case BOOT_DEVICE_ETHERNET_RGMII:
+		fallthrough;
+	case BOOT_DEVICE_ETHERNET_RMII:
+		return BOOT_DEVICE_ETHERNET;
+
+	case BOOT_DEVICE_EMMC:
+		return BOOT_DEVICE_MMC1;
+
+	case BOOT_DEVICE_MMC:
+		if ((bootmode_cfg & MAIN_DEVSTAT_PRIMARY_MMC_PORT_MASK) >>
+				MAIN_DEVSTAT_PRIMARY_MMC_PORT_SHIFT)
+			return BOOT_DEVICE_MMC2;
+		return BOOT_DEVICE_MMC1;
+
+	case BOOT_DEVICE_DFU:
+		if ((bootmode_cfg & MAIN_DEVSTAT_PRIMARY_USB_MODE_MASK) >>
+		    MAIN_DEVSTAT_PRIMARY_USB_MODE_SHIFT)
+			return BOOT_DEVICE_USB;
+		return BOOT_DEVICE_DFU;
+
+	case BOOT_DEVICE_NOBOOT:
+		return BOOT_DEVICE_RAM;
+	}
+
+	return bootmode;
+}
+
+u32 get_boot_device(void)
+{
+	u32 devstat = readl(CTRLMMR_MAIN_DEVSTAT);
+	u32 bootmode = *(u32 *)(K3_BOOT_PARAM_TABLE_INDEX_OCRAM);
+	u32 bootmedia;
+
+	if (bootmode == K3_PRIMARY_BOOTMODE)
+		bootmedia = __get_primary_bootmedia(devstat);
+	else
+		bootmedia = __get_backup_bootmedia(devstat);
+
+	debug("%s: devstat = 0x%x bootmedia = 0x%x bootmode = %d\n",
+	      __func__, devstat, bootmedia, bootmode);
+
+	return bootmedia;
+}