spl: add overall SPL size check
This adds a size check for SPL that can dynamically check generated
SPL binaries (including devicetree) for a size limit that ensures
this image plus global data, heap and stack fit in initial SRAM.
Since some of these sizes are not available to make, a new host tool
'spl_size_limit' is added that dumps the resulting maximum size for
an SPL binary to stdout. This tool is used in toplevel Makefile to
implement the size check on SPL binaries.
Signed-off-by: Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
diff --git a/tools/spl_size_limit.c b/tools/spl_size_limit.c
new file mode 100644
index 0000000..98ff491
--- /dev/null
+++ b/tools/spl_size_limit.c
@@ -0,0 +1,30 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (c) 2019, Simon Goldschmidt <simon.k.r.goldschmidt@gmail.com>
+ *
+ * This tool helps to return the size available for SPL image during build
+ */
+
+#include <generated/autoconf.h>
+#include <generated/generic-asm-offsets.h>
+
+int main(int argc, char *argv[])
+{
+ int spl_size_limit = 0;
+
+#ifdef CONFIG_SPL_SIZE_LIMIT
+ spl_size_limit = CONFIG_SPL_SIZE_LIMIT;
+#ifdef CONFIG_SPL_SIZE_LIMIT_SUBTRACT_GD
+ spl_size_limit -= GENERATED_GBL_DATA_SIZE;
+#endif
+#ifdef CONFIG_SPL_SIZE_LIMIT_SUBTRACT_MALLOC
+ spl_size_limit -= CONFIG_SPL_SYS_MALLOC_F_LEN;
+#endif
+#ifdef CONFIG_SPL_SIZE_LIMIT_PROVIDE_STACK
+ spl_size_limit -= CONFIG_SPL_SIZE_LIMIT_PROVIDE_STACK;
+#endif
+#endif
+
+ printf("%d", spl_size_limit);
+ return 0;
+}
