Implement skiboot versioning

We grab a version from git tags (or SKIBOOT_VERSION environment variable),
optionally tack on EXTRA_VERSION (if from git) as well as add things to the
git version number if we're ahead of the most recent tag or the tree is dirty.

Also fix-up makefiles so that we don't have to rebuild version.c every time
you run make.

fsp attn area needed updating as we can have >40 character version strings.

We also export the version string via device tree rather than just the gitid.

For buildroot builds, setting SKIBOOT_VERSION environment variable to the
tag you grab will do the correct thing.

Signed-off-by: Stewart Smith <stewart@linux.vnet.ibm.com>

8 files changed, 65 insertions, 18 deletions

diff --git a/.gitignore b/.gitignore
index 20fe583..fb5ed3a 100644
--- a/.gitignore
+++ b/.gitignore
@@ -17,7 +17,7 @@ tags
 cscope.out
 asm/asm-offsets.s
 include/asm-offsets.h
-gitid.c
+version.c
 core/test/run-device
 core/test/run-malloc
 core/test/run-malloc-speed
@@ -36,3 +36,4 @@ libc/test/run-time
 libc/test/run-time-gcov
 libflash/test/test-flash
 libflash/test/test-flash-gcov
+VERSION
diff --git a/Makefile.main b/Makefile.main
index 4df3cfd..b584eb8 100644
--- a/Makefile.main
+++ b/Makefile.main
@@ -108,13 +108,15 @@ OBJS := $(ASM) $(CORE) $(HW) $(PLATFORMS) $(LIBFDT) $(LIBFLASH)
 ifeq ($(PORE),1)
 OBJS += $(LIBPORE)
 endif
-OBJS += $(LIBC) $(CCAN) $(DEVSRC_OBJ) gitid.o
+OBJS += $(LIBC) $(CCAN) $(DEVSRC_OBJ)
+OBJS_NO_VER = $(OBJS)
+ALL_OBJS = $(OBJS) version.o
 
 $(TARGET).lid: $(TARGET).elf
 	$(call Q,OBJCOPY, $(OBJCOPY) -O binary -S $^ $@, $@)
 
-$(TARGET).elf: $(OBJS) $(TARGET).lds $(KERNEL)
-	$(call Q,LD, $(CC) $(LDFLAGS) -T $(TARGET).lds $(OBJS) -o $@, $@)
+$(TARGET).elf: $(ALL_OBJS) $(TARGET).lds $(KERNEL)
+	$(call Q,LD, $(CC) $(LDFLAGS) -T $(TARGET).lds $(ALL_OBJS) -o $@, $@)
 
 $(TARGET).map: $(TARGET).elf
 	$(call Q,NM, $(NM) -n $< | grep -v '\( [aNUw] \)\|\(__crc_\)\|\( \$[adt]\)' > $@, $@)
@@ -128,10 +130,16 @@ $(SUBDIRS):
 # Set V=1 if you want to see everything.
 include $(SRC)/Makefile.rules
 
-GIT_SHA ?= $(shell cd $(SRC); GIT_DIR=$(SRC)/.git git describe --always --dirty 2> /dev/null)
+VERSION ?= $(shell cd $(SRC); GIT_DIR=$(SRC)/.git $(SRC)/make_version.sh)
 
-gitid.c:
-	@echo "const char gitid[] = \"$(GIT_SHA)\";" > $@
+.PHONY: VERSION-always
+.version: VERSION-always
+	@echo $(VERSION) > $@.tmp
+	@cmp -s $@ $@.tmp || cp $@.tmp $@
+	@rm -f $@.tmp
+
+version.c: make_version.sh $(OBJS_NO_VER) .version
+	@echo "const char version[] = \"$(VERSION)\";" > $@
 
 .PHONY: coverage
 include $(shell find $(SRC)/* -name Makefile.check)
@@ -149,7 +157,7 @@ tags:
 TAGS:
 	find . -name '*.[chS]' | xargs etags
 
-.PHONY: tags TAGS check gitid.c
+.PHONY: tags TAGS check
 
 cscope:
 	find . -name '*.[chS]' | xargs cscope
@@ -157,7 +165,7 @@ cscope:
 clean:
 	$(RM) *.[odsa] $(SUBDIRS:%=%/*.[odsa])
 	$(RM) $(TARGET).elf $(TARGET).lid $(TARGET).map $(TARGET).lds
-	$(RM) include/asm-offsets.h gitid.c
+	$(RM) include/asm-offsets.h version.c
 
 distclean: clean
 	$(RM) *~ $(SUBDIRS:%=%/*~) include/*~
diff --git a/core/init.c b/core/init.c
index 1d32be5..a522493 100644
--- a/core/init.c
+++ b/core/init.c
@@ -493,7 +493,7 @@ void __noreturn main_cpu_entry(const void *fdt, u32 master_cpu)
 	 */
 	clear_console();
 
-	printf("SkiBoot %s starting...\n", gitid);
+	printf("SkiBoot %s starting...\n", version);
 	printf("initial console log level: memory %d, driver %d\n",
 	       (debug_descriptor.console_log_levels >> 4),
 	       (debug_descriptor.console_log_levels & 0x0f));
diff --git a/core/opal.c b/core/opal.c
index 5e1c742..deb5aff 100644
--- a/core/opal.c
+++ b/core/opal.c
@@ -118,7 +118,7 @@ static void add_opal_firmware_node(void)
 
 	dt_add_property_string(firmware, "compatible", "ibm,opal-firmware");
 	dt_add_property_string(firmware, "name", "firmware");
-	dt_add_property_string(firmware, "git-id", gitid);
+	dt_add_property_string(firmware, "version", version);
 }
 
 void add_opal_node(void)
diff --git a/hw/fsp/fsp-attn.c b/hw/fsp/fsp-attn.c
index 755b95d..144b545 100644
--- a/hw/fsp/fsp-attn.c
+++ b/hw/fsp/fsp-attn.c
@@ -98,11 +98,11 @@ void update_sp_attn_area(const char *msg)
 	ti_attn->src_word[0] =
 		(uint32_t)((uint64_t)__builtin_return_address(0) & 0xffffffff);
 
-	snprintf(ti_attn->msg.gitid, GITID_LEN, "%s", gitid);
+	snprintf(ti_attn->msg.version, VERSION_LEN, "%s", version);
 	__backtrace(ti_attn->msg.bt_buf, BT_FRAME_LEN);
 	snprintf(ti_attn->msg.file_info, FILE_INFO_LEN, "%s", msg);
 
-	ti_attn->msg_len = GITID_LEN + BT_FRAME_LEN +
+	ti_attn->msg_len = VERSION_LEN + BT_FRAME_LEN +
                                    strlen(ti_attn->msg.file_info);
 }
 
diff --git a/include/fsp-attn.h b/include/fsp-attn.h
index 947c49f..1eaa5bb 100644
--- a/include/fsp-attn.h
+++ b/include/fsp-attn.h
@@ -59,14 +59,14 @@ struct sp_attn_area {
 #define TI_MSG_LEN	940
 
 /* Maximum sapphire version length (approx) */
-#define GITID_LEN	40
+#define VERSION_LEN	80
 /* Upto 10 frames each of length 40 bytes + header = 430 bytes */
 #define BT_FRAME_LEN 430
 /* File info length : Use the rest of the memory for file details */
-#define FILE_INFO_LEN	(TI_MSG_LEN - GITID_LEN - BT_FRAME_LEN)
+#define FILE_INFO_LEN	(TI_MSG_LEN - VERSION_LEN - BT_FRAME_LEN)
 
 struct user_data {
-	char		gitid[GITID_LEN];
+	char		version[VERSION_LEN];
 	char		bt_buf[BT_FRAME_LEN];
 	char		file_info[FILE_INFO_LEN];
 } __packed;
diff --git a/include/skiboot.h b/include/skiboot.h
index 1a1f96f..b65475b 100644
--- a/include/skiboot.h
+++ b/include/skiboot.h
@@ -175,8 +175,8 @@ extern void parse_hdat(bool is_opal, uint32_t master_cpu);
 /* Root of device tree. */
 extern struct dt_node *dt_root;
 
-/* Generated git id. */
-extern const char gitid[];
+/* Full skiboot version number (possibly includes gitid). */
+extern const char version[];
 
 /* Fast reboot support */
 extern void fast_reset(void);
diff --git a/make_version.sh b/make_version.sh
new file mode 100755
index 0000000..1409704
--- /dev/null
+++ b/make_version.sh
@@ -0,0 +1,38 @@
+#!/bin/bash
+
+if test -d .git;
+then
+	version=`git describe --exact-match 2>/dev/null`
+	if [ -z "$version" ];
+	then
+		version=`git describe 2>/dev/null`
+	fi
+	if [ -z "$version" ];
+	then
+		version=`git rev-parse --verify --short HEAD 2>/dev/null`
+	fi
+	if [ ! -z "$EXTRA_VERSION" ];
+	then
+		version="$version-$EXTRA_VERSION"
+	fi
+	if git diff-index --name-only HEAD |grep -qv '.git';
+	then
+		if [ ! -z "$USER" ];
+		then
+			version="$version-$USER"
+		fi
+		version="$version-dirty"
+		diffsha=`git diff|sha1sum`
+		diffsha=`cut -c-7 <<< "$diffsha"`
+		version="$version-$diffsha"
+	fi
+
+	echo $version
+else
+	if [ ! -z "$SKIBOOT_VERSION" ];
+	then
+		echo $SKIBOOT_VERSION
+	else
+		exit 1;
+	fi
+fi