ti: omap-common: Add commands for generating secure SPL images

Adds a centralized config_secure.mk in omap-common for
OMAP-style TI secure devices to use for boot image generation

Depending on the boot media, different images are needed for
secure devices. These commands generates u-boot*_HS_* files that
need to be used to boot secure devices.

Please refer to README.ti-secure for more information.

Signed-off-by: Daniel Allred <d-allred@ti.com>
Signed-off-by: Madan Srinivas <madans@ti.com>

Reviewed-by: Lokesh Vutla <lokeshvutla@ti.com>
Tested-by: Andreas Dannenberg <dannenberg@ti.com>
Reviewed-by: Tom Rini <trini@konsulko.com>

arch/arm/cpu/armv7/omap-common/config_secure.mk

+#
+# Copyright (C) 2016, Texas Instruments, Incorporated - http://www.ti.com/
+#
+# SPDX-License-Identifier:	GPL-2.0+
+#
+quiet_cmd_mkomapsecimg = MKIMAGE $@
+ifneq ($(TI_SECURE_DEV_PKG),)
+ifneq ($(wildcard $(TI_SECURE_DEV_PKG)/scripts/create-boot-image.sh),)
+ifneq ($(CONFIG_SPL_BUILD),)
+cmd_mkomapsecimg = $(TI_SECURE_DEV_PKG)/scripts/create-boot-image.sh \
+	$(patsubst u-boot-spl_HS_%,%,$(@F)) $< $@ $(CONFIG_ISW_ENTRY_ADDR) \
+	$(if $(KBUILD_VERBOSE:1=), >/dev/null)
+else
+cmd_mkomapsecimg = $(TI_SECURE_DEV_PKG)/scripts/create-boot-image.sh \
+    $(patsubst u-boot_HS_%,%,$(@F)) $< $@ $(CONFIG_ISW_ENTRY_ADDR) \
+    $(if $(KBUILD_VERBOSE:1=), >/dev/null)
+endif
+else
+cmd_mkomapsecimg = echo "WARNING:" \
+	"$(TI_SECURE_DEV_PKG)/scripts/create-boot-image.sh not found." \
+	"$@ was NOT created!"
+endif
+else
+cmd_mkomapsecimg = echo "WARNING: TI_SECURE_DEV_PKG environment" \
+	"variable must be defined for TI secure devices. $@ was NOT created!"
+endif
+
+# Standard X-LOADER target (QPSI, NOR flash)
+u-boot-spl_HS_X-LOADER: $(obj)/u-boot-spl.bin
+	$(call if_changed,mkomapsecimg)
+
+# For MLO targets (SD card boot) the final file name
+# that is copied to the SD card fAT partition must
+# be MLO, so we make a copy of the output file to a
+# new file with that name
+u-boot-spl_HS_MLO: $(obj)/u-boot-spl.bin
+	$(call if_changed,mkomapsecimg)
+	@if [ -f $@ ]; then \
+		cp -f $@ MLO; \
+	fi
+
+# Standard 2ND target (certain peripheral boot modes)
+u-boot-spl_HS_2ND: $(obj)/u-boot-spl.bin
+	$(call if_changed,mkomapsecimg)
+
+# Standard ULO target (certain peripheral boot modes)
+u-boot-spl_HS_ULO: $(obj)/u-boot-spl.bin
+	$(call if_changed,mkomapsecimg)
+
+# Standard ISSW target (certain devices, various boot modes)
+u-boot-spl_HS_ISSW: $(obj)/u-boot-spl.bin
+	$(call if_changed,mkomapsecimg)
+
+# For SPI flash on AM335x and AM43xx, these
+# require special byte swap handling so we use
+# the SPI_X-LOADER target instead of X-LOADER
+# and let the create-boot-image.sh script handle
+# that
+u-boot-spl_HS_SPI_X-LOADER: $(obj)/u-boot-spl.bin
+	$(call if_changed,mkomapsecimg)
+
+# For supporting single stage XiP QSPI on AM43xx, the
+# image is a full u-boot file, not an SPL. In this case
+# the mkomapsecimg command looks for a u-boot-HS_* prefix
+u-boot_HS_XIP_X-LOADER: $(obj)/u-boot.bin
+	$(call if_changed,mkomapsecimg)