TPL : introduce the TPL based on the SPL

Due to the nand SPL on some board(e.g. P1022DS)has a size limit, it can
not be more than 4K. So, the SPL cannot initialize the DDR with the SPD
code. This patch introduces TPL to enable a loader stub that is loaded
by the code from the SPL. It initializes the DDR with the SPD or other
operations.

The TPL's size is sizeable, the maximum size is decided by the memory's
size that TPL runs. It initializes the DDR through SPD code, and copys
final uboot image to DDR. So there are three stage uboot images:
	* spl_boot, * tpl_boot, * final uboot image

Signed-off-by: Ying Zhang <b40530@freescale.com>
Acked-by: York Sun <yorksun@freescale.com>

5 files changed, 147 insertions, 14 deletions

diff --git a/Makefile b/Makefile
index 43b57da325..8d7159daa7 100644
--- a/Makefile
+++ b/Makefile
@@ -102,10 +102,11 @@ endif # ifneq ($(BUILD_DIR),)
 
 OBJTREE		:= $(if $(BUILD_DIR),$(BUILD_DIR),$(CURDIR))
 SPLTREE		:= $(OBJTREE)/spl
+TPLTREE		:= $(OBJTREE)/tpl
 SRCTREE		:= $(CURDIR)
 TOPDIR		:= $(SRCTREE)
 LNDIR		:= $(OBJTREE)
-export	TOPDIR SRCTREE OBJTREE SPLTREE
+export	TOPDIR SRCTREE OBJTREE SPLTREE TPLTREE
 
 MKCONFIG	:= $(SRCTREE)/mkconfig
 export MKCONFIG
@@ -397,6 +398,7 @@ ALL-y += $(obj)u-boot.srec $(obj)u-boot.bin $(obj)System.map
 ALL-$(CONFIG_NAND_U_BOOT) += $(obj)u-boot-nand.bin
 ALL-$(CONFIG_ONENAND_U_BOOT) += $(obj)u-boot-onenand.bin
 ALL-$(CONFIG_SPL) += $(obj)spl/u-boot-spl.bin
+ALL-$(CONFIG_TPL) += $(obj)tpl/u-boot-tpl.bin
 ALL-$(CONFIG_OF_SEPARATE) += $(obj)u-boot.dtb $(obj)u-boot-dtb.bin
 ifneq ($(CONFIG_SPL_TARGET),)
 ALL-$(CONFIG_SPL) += $(obj)$(subst ",,$(CONFIG_SPL_TARGET))
@@ -475,13 +477,25 @@ $(obj)u-boot.sha1:	$(obj)u-boot.bin
 $(obj)u-boot.dis:	$(obj)u-boot
 		$(OBJDUMP) -d $< > $@
 
+# $@ is output, $(1) and $(2) are inputs, $(3) is padded intermediate,
+# $(4) is pad-to
+SPL_PAD_APPEND = \
+		$(OBJCOPY) ${OBJCFLAGS} --pad-to=$(4) -I binary -O binary \
+		$(1) $(obj)$(3); \
+		cat $(obj)$(3) $(obj)$(2) > $@; \
+		rm $(obj)$(3)
 
+ifdef CONFIG_TPL
+SPL_PAYLOAD := $(obj)tpl/u-boot-with-tpl.bin
+else
+SPL_PAYLOAD := $(obj)u-boot.bin
+endif
 
-$(obj)u-boot-with-spl.bin: $(obj)spl/u-boot-spl.bin $(obj)u-boot.bin
-		$(OBJCOPY) ${OBJCFLAGS} --pad-to=$(CONFIG_SPL_PAD_TO) \
-			-I binary -O binary $< $(obj)spl/u-boot-spl-pad.bin
-		cat $(obj)spl/u-boot-spl-pad.bin $(obj)u-boot.bin > $@
-		rm $(obj)spl/u-boot-spl-pad.bin
+$(obj)u-boot-with-spl.bin: $(obj)spl/u-boot-spl.bin $(SPL_PAYLOAD)
+		$(call SPL_PAD_APPEND,$<,$(SPL_PAYLOAD),spl/u-boot-spl-pad.bin,$(CONFIG_SPL_PAD_TO))
+
+$(obj)tpl/u-boot-with-tpl.bin: $(obj)tpl/u-boot-tpl.bin $(obj)u-boot.bin
+		$(call SPL_PAD_APPEND,$<,u-boot.bin,tpl/u-boot-tpl-pad.bin,$(CONFIG_TPL_PAD_TO))
 
 $(obj)u-boot-with-spl.imx: $(obj)spl/u-boot-spl.bin $(obj)u-boot.bin
 		$(MAKE) -C $(SRCTREE)/arch/arm/imx-common \
@@ -607,6 +621,9 @@ $(obj)u-boot-nand.bin:	nand_spl $(obj)u-boot.bin
 $(obj)spl/u-boot-spl.bin:	$(SUBDIR_TOOLS) depend
 		$(MAKE) -C spl all
 
+$(obj)tpl/u-boot-tpl.bin:	$(SUBDIR_TOOLS) depend
+		$(MAKE) -C spl all CONFIG_TPL_BUILD=y
+
 updater:
 		$(MAKE) -C tools/updater all
 
@@ -614,6 +631,7 @@ updater:
 # parallel sub-makes creating .depend files simultaneously.
 depend dep:	$(TIMESTAMP_FILE) $(VERSION_FILE) \
 		$(obj)include/spl-autoconf.mk \
+		$(obj)include/tpl-autoconf.mk \
 		$(obj)include/autoconf.mk \
 		$(obj)include/generated/generic-asm-offsets.h \
 		$(obj)include/generated/asm-offsets.h
@@ -696,6 +714,15 @@ $(obj)include/autoconf.mk: $(obj)include/config.h
 	mv $@.tmp $@
 
 # Auto-generate the spl-autoconf.mk file (which is included by all makefiles for SPL)
+$(obj)include/tpl-autoconf.mk: $(obj)include/config.h
+	@$(XECHO) Generating $@ ; \
+	set -e ; \
+	: Extract the config macros ; \
+	$(CPP) $(CFLAGS) -DCONFIG_TPL_BUILD  -DCONFIG_SPL_BUILD\
+			-DDO_DEPS_ONLY -dM include/common.h | \
+	sed -n -f tools/scripts/define2mk.sed > $@.tmp && \
+	mv $@.tmp $@
+
 $(obj)include/spl-autoconf.mk: $(obj)include/config.h
 	@$(XECHO) Generating $@ ; \
 	set -e ; \
@@ -706,12 +733,14 @@ $(obj)include/spl-autoconf.mk: $(obj)include/config.h
 
 $(obj)include/generated/generic-asm-offsets.h:	$(obj)include/autoconf.mk.dep \
 	$(obj)include/spl-autoconf.mk \
+	$(obj)include/tpl-autoconf.mk \
 	$(obj)lib/asm-offsets.s
 	@$(XECHO) Generating $@
 	tools/scripts/make-asm-offsets $(obj)lib/asm-offsets.s $@
 
 $(obj)lib/asm-offsets.s:	$(obj)include/autoconf.mk.dep \
 	$(obj)include/spl-autoconf.mk \
+	$(obj)include/tpl-autoconf.mk \
 	$(src)lib/asm-offsets.c
 	@mkdir -p $(obj)lib
 	$(CC) -DDO_DEPS_ONLY \
@@ -720,12 +749,14 @@ $(obj)lib/asm-offsets.s:	$(obj)include/autoconf.mk.dep \
 
 $(obj)include/generated/asm-offsets.h:	$(obj)include/autoconf.mk.dep \
 	$(obj)include/spl-autoconf.mk \
+	$(obj)include/tpl-autoconf.mk \
 	$(obj)$(CPUDIR)/$(SOC)/asm-offsets.s
 	@$(XECHO) Generating $@
 	tools/scripts/make-asm-offsets $(obj)$(CPUDIR)/$(SOC)/asm-offsets.s $@
 
 $(obj)$(CPUDIR)/$(SOC)/asm-offsets.s:	$(obj)include/autoconf.mk.dep \
-	$(obj)include/spl-autoconf.mk
+	$(obj)include/spl-autoconf.mk \
+	$(obj)include/tpl-autoconf.mk
 	@mkdir -p $(obj)$(CPUDIR)/$(SOC)
 	if [ -f $(src)$(CPUDIR)/$(SOC)/asm-offsets.c ];then \
 		$(CC) -DDO_DEPS_ONLY \
@@ -798,7 +829,8 @@ unconfig:
 	@rm -f $(obj)include/config.h $(obj)include/config.mk \
 		$(obj)board/*/config.tmp $(obj)board/*/*/config.tmp \
 		$(obj)include/autoconf.mk $(obj)include/autoconf.mk.dep \
-		$(obj)include/spl-autoconf.mk
+		$(obj)include/spl-autoconf.mk \
+		$(obj)include/tpl-autoconf.mk
 
 %_config::	unconfig
 	@$(MKCONFIG) -A $(@:_config=)
@@ -884,6 +916,8 @@ clobber:	tidy
 	@rm -f $(obj)nand_spl/{u-boot-nand_spl.lds,u-boot-spl,u-boot-spl.map}
 	@rm -f $(obj)spl/{u-boot-spl,u-boot-spl.bin,u-boot-spl.map}
 	@rm -f $(obj)spl/u-boot-spl.lds
+	@rm -f $(obj)tpl/{u-boot-tpl,u-boot-tpl.bin,u-boot-tpl.map}
+	@rm -f $(obj)tpl/u-boot-spl.lds
 	@rm -f $(obj)MLO MLO.byteswap
 	@rm -f $(obj)SPL
 	@rm -f $(obj)tools/xway-swap-bytes
diff --git a/README b/README
index 18f5233ace..677c3dc252 100644
--- a/README
+++ b/README
@@ -3167,6 +3167,17 @@ FIT uImage format:
 		option to re-enable it. This will affect the output of the
 		bootm command when booting a FIT image.
 
+- TPL framework
+		CONFIG_TPL
+		Enable building of TPL globally.
+
+		CONFIG_TPL_PAD_TO
+		Image offset to which the TPL should be padded before appending
+		the TPL payload. By default, this is defined as
+                CONFIG_SPL_MAX_SIZE, or 0 if CONFIG_SPL_MAX_SIZE is undefined.
+                CONFIG_SPL_PAD_TO must be either 0, meaning to append the SPL
+                payload without any padding, or >= CONFIG_SPL_MAX_SIZE.
+
 Modem Support:
 --------------
 
@@ -4204,6 +4215,11 @@ Low Level (hardware related) configuration options:
 		that is executed before the actual U-Boot. E.g. when
 		compiling a NAND SPL.
 
+- CONFIG_TPL_BUILD
+		Modifies the behaviour of start.S  when compiling a loader
+		that is executed after the SPL and before the actual U-Boot.
+		It is loaded by the SPL.
+
 - CONFIG_SYS_MPC85XX_NO_RESETVEC
 		Only for 85xx systems. If this variable is specified, the section
 		.resetvec is not kept and the section .bootpg is placed in the
diff --git a/config.mk b/config.mk
index 54e99f4da3..b3ecaa7f80 100644
--- a/config.mk
+++ b/config.mk
@@ -13,6 +13,12 @@ SHELL := $(shell if [ -x "$$BASH" ]; then echo $$BASH; \
 
 export	SHELL
 
+ifeq ($(CONFIG_TPL_BUILD),y)
+SPL_BIN := u-boot-tpl
+else
+SPL_BIN := u-boot-spl
+endif
+
 ifeq ($(CURDIR),$(SRCTREE))
 dir :=
 else
@@ -22,7 +28,11 @@ endif
 ifneq ($(OBJTREE),$(SRCTREE))
 # Create object files for SPL in a separate directory
 ifeq ($(CONFIG_SPL_BUILD),y)
+ifeq ($(CONFIG_TPL_BUILD),y)
+obj := $(if $(dir),$(TPLTREE)/$(dir)/,$(TPLTREE)/)
+else
 obj := $(if $(dir),$(SPLTREE)/$(dir)/,$(SPLTREE)/)
+endif
 else
 obj := $(if $(dir),$(OBJTREE)/$(dir)/,$(OBJTREE)/)
 endif
@@ -32,8 +42,12 @@ $(shell mkdir -p $(obj))
 else
 # Create object files for SPL in a separate directory
 ifeq ($(CONFIG_SPL_BUILD),y)
+ifeq ($(CONFIG_TPL_BUILD),y)
+obj := $(if $(dir),$(TPLTREE)/$(dir)/,$(TPLTREE)/)
+else
 obj := $(if $(dir),$(SPLTREE)/$(dir)/,$(SPLTREE)/)
 
+endif
 $(shell mkdir -p $(obj))
 else
 obj :=
@@ -145,6 +159,10 @@ CHECK	= sparse
 #########################################################################
 
 # Load generated board configuration
+ifeq ($(CONFIG_TPL_BUILD),y)
+# Include TPL autoconf
+sinclude $(OBJTREE)/include/tpl-autoconf.mk
+else
 ifeq ($(CONFIG_SPL_BUILD),y)
 # Include SPL autoconf
 sinclude $(OBJTREE)/include/spl-autoconf.mk
@@ -152,6 +170,7 @@ else
 # Include normal autoconf
 sinclude $(OBJTREE)/include/autoconf.mk
 endif
+endif
 sinclude $(OBJTREE)/include/config.mk
 
 # Some architecture config.mk files need to know what CPUDIR is set to,
@@ -221,12 +240,19 @@ ifneq ($(CONFIG_SPL_PAD_TO),)
 CPPFLAGS += -DCONFIG_SPL_PAD_TO=$(CONFIG_SPL_PAD_TO)
 endif
 
+ifneq ($(CONFIG_TPL_PAD_TO),)
+CPPFLAGS += -DCONFIG_TPL_PAD_TO=$(CONFIG_TPL_PAD_TO)
+endif
+
 ifneq ($(CONFIG_UBOOT_PAD_TO),)
 CPPFLAGS += -DCONFIG_UBOOT_PAD_TO=$(CONFIG_UBOOT_PAD_TO)
 endif
 
 ifeq ($(CONFIG_SPL_BUILD),y)
 CPPFLAGS += -DCONFIG_SPL_BUILD
+ifeq ($(CONFIG_TPL_BUILD),y)
+CPPFLAGS += -DCONFIG_TPL_BUILD
+endif
 endif
 
 # Does this architecture support generic board init?
@@ -298,9 +324,9 @@ ifneq ($(CONFIG_SYS_TEXT_BASE),)
 LDFLAGS_u-boot += -Ttext $(CONFIG_SYS_TEXT_BASE)
 endif
 
-LDFLAGS_u-boot-spl += -T $(obj)u-boot-spl.lds $(LDFLAGS_FINAL)
+LDFLAGS_$(SPL_BIN) += -T $(obj)u-boot-spl.lds $(LDFLAGS_FINAL)
 ifneq ($(CONFIG_SPL_TEXT_BASE),)
-LDFLAGS_u-boot-spl += -Ttext $(CONFIG_SPL_TEXT_BASE)
+LDFLAGS_$(SPL_BIN) += -Ttext $(CONFIG_SPL_TEXT_BASE)
 endif
 
 # Linus' kernel sanity checking tool
diff --git a/doc/README.TPL b/doc/README.TPL
new file mode 100644
index 0000000000..1df03b958e
--- /dev/null
+++ b/doc/README.TPL
@@ -0,0 +1,45 @@
+Generic TPL framework
+=====================
+
+Overview
+--------
+
+TPL---Third Program Loader.
+
+Due to the SPL on some boards(powerpc mpc85xx) has a size limit and cannot
+be compatible with all the external device(e.g. DDR). So add a tertiary
+program loader (TPL) to enable a loader stub loaded by the code from the
+SPL. It loads the final uboot image into DDR, then jump to it to begin
+execution. Now, only the powerpc mpc85xx has this requirement and will
+implemente it.
+
+Keep consistent with SPL, with this framework almost all source files for a
+board can be reused. No code duplication or symlinking is necessary anymore.
+
+How it works
+------------
+
+There has been a directory TOPDIR/spl which contains only a Makefile. The
+Makefile is shared by SPL and TPL.
+
+The object files are built separately for SPL/TPL and placed in the
+directory spl/tpl. The final binaries which are generated are
+u-boot-{spl|tpl}, u-boot-{spl|tpl}.bin and u-boot-{spl|tpl}.map.
+
+During the TPL build a variable named CONFIG_TPL_BUILD is exported in the
+make environment and also appended to CPPFLAGS with -DCONFIG_TPL_BUILD.
+
+The SPL options are shared by SPL and TPL, the board config file should
+determine which SPL options to choose based on whether CONFIG_TPL_BUILD
+is set. Source files can be compiled for TPL with options choosed in the
+board config file.
+
+For example:
+
+spl/Makefile:
+LIBS-$(CONFIG_SPL_LIBCOMMON_SUPPORT) += common/libcommon.o
+
+CONFIG_SPL_LIBCOMMON_SUPPORT is defined in board config file:
+#ifdef CONFIG_TPL_BUILD
+#define CONFIG_SPL_LIBCOMMON_SUPPORT
+#endif
diff --git a/spl/Makefile b/spl/Makefile
index a9a8564f62..339e5e8971 100644
--- a/spl/Makefile
+++ b/spl/Makefile
@@ -17,10 +17,22 @@
 CONFIG_SPL_BUILD := y
 export CONFIG_SPL_BUILD
 
+ifeq ($(CONFIG_TPL_BUILD),y)
+export CONFIG_TPL_BUILD
+SPL_BIN := u-boot-tpl
+else
+SPL_BIN := u-boot-spl
+endif
+
 include $(TOPDIR)/config.mk
 
 # We want the final binaries in this directory
+ifeq ($(CONFIG_TPL_BUILD),y)
+obj := $(OBJTREE)/tpl/
+SPLTREE := $(TPLTREE)
+else
 obj := $(OBJTREE)/spl/
+endif
 
 HAVE_VENDOR_COMMON_LIB = $(if $(wildcard $(SRCTREE)/board/$(VENDOR)/common/Makefile),y,n)
 
@@ -161,7 +173,7 @@ $(OBJTREE)/MLO.byteswap: $(obj)u-boot-spl.bin
 $(OBJTREE)/SPL : $(obj)u-boot-spl.bin depend
 		$(MAKE) -C $(SRCTREE)/arch/arm/imx-common $@
 
-ALL-y	+= $(obj)u-boot-spl.bin
+ALL-y	+= $(obj)$(SPL_BIN).bin
 
 ifdef CONFIG_SAMSUNG
 ALL-y	+= $(obj)$(BOARD)-spl.bin
@@ -175,15 +187,15 @@ $(obj)$(BOARD)-spl.bin: $(obj)u-boot-spl.bin
 		$(obj)u-boot-spl.bin $(obj)$(BOARD)-spl.bin
 endif
 
-$(obj)u-boot-spl.bin:	$(obj)u-boot-spl
+$(obj)$(SPL_BIN).bin:	$(obj)$(SPL_BIN)
 	$(OBJCOPY) $(OBJCFLAGS) -O binary $< $@
 
 GEN_UBOOT = \
 	cd $(obj) && $(LD) $(LDFLAGS) $(LDFLAGS_$(@F)) $(__START) \
 		--start-group $(__LIBS) --end-group $(PLATFORM_LIBS) \
-		-Map u-boot-spl.map -o u-boot-spl
+		-Map $(SPL_BIN).map -o $(SPL_BIN)
 
-$(obj)u-boot-spl:	depend $(START) $(LIBS) $(obj)u-boot-spl.lds
+$(obj)$(SPL_BIN):	depend $(START) $(LIBS) $(obj)u-boot-spl.lds
 	$(GEN_UBOOT)
 
 $(START):	depend