bootm: Export bootm_decomp_image()

Export this function for testing. Also add a parameter so that values other
than CONFIG_SYS_BOOTM_LEN can be used for the maximum uncompressed size.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/common/bootm.c b/common/bootm.c
index 915d537..10c15ef 100644
--- a/common/bootm.c
+++ b/common/bootm.c
@@ -289,23 +289,11 @@
 }
 #endif
 
-/**
- * decomp_image() - decompress the operating system
- *
- * @comp:	Compression algorithm that is used (IH_COMP_...)
- * @load:	Destination load address in U-Boot memory
- * @image_start Image start address (where we are decompressing from)
- * @type:	OS type (IH_OS_...)
- * @load_bug:	Place to decompress to
- * @image_buf:	Address to decompress from
- * @return 0 if OK, -ve on error (BOOTM_ERR_...)
- */
-static int decomp_image(int comp, ulong load, ulong image_start, int type,
-			void *load_buf, void *image_buf, ulong image_len,
-			ulong *load_end)
+int bootm_decomp_image(int comp, ulong load, ulong image_start, int type,
+		       void *load_buf, void *image_buf, ulong image_len,
+		       uint unc_len, ulong *load_end)
 {
 	const char *type_name = genimg_get_type_name(type);
-	__attribute__((unused)) uint unc_len = CONFIG_SYS_BOOTM_LEN;
 
 	*load_end = load;
 	switch (comp) {
@@ -413,8 +401,9 @@
 
 	load_buf = map_sysmem(load, 0);
 	image_buf = map_sysmem(os.image_start, image_len);
-	err = decomp_image(os.comp, load, os.image_start, os.type, load_buf,
-			   image_buf, image_len, load_end);
+	err = bootm_decomp_image(os.comp, load, os.image_start, os.type,
+				 load_buf, image_buf, image_len,
+				 CONFIG_SYS_BOOTM_LEN, load_end);
 	if (err) {
 		bootstage_error(BOOTSTAGE_ID_DECOMP_IMAGE);
 		return err;
@@ -905,9 +894,11 @@
 
 	/* Allow the image to expand by a factor of 4, should be safe */
 	load_buf = malloc((1 << 20) + len * 4);
-	ret = decomp_image(imape_comp, 0, data, image_type, load_buf,
-			   (void *)data, len, &load_end);
+	ret = bootm_decomp_image(imape_comp, 0, data, image_type, load_buf,
+				 (void *)data, len, CONFIG_SYS_BOOTM_LEN,
+				 &load_end);
 	free(load_buf);
+
 	if (ret && ret != BOOTM_ERR_UNIMPLEMENTED)
 		return ret;
 
diff --git a/include/bootm.h b/include/bootm.h
index b3d1a62..6181488 100644
--- a/include/bootm.h
+++ b/include/bootm.h
@@ -56,4 +56,21 @@
 
 void arch_preboot_os(void);
 
+/**
+ * bootm_decomp_image() - decompress the operating system
+ *
+ * @comp:	Compression algorithm that is used (IH_COMP_...)
+ * @load:	Destination load address in U-Boot memory
+ * @image_start Image start address (where we are decompressing from)
+ * @type:	OS type (IH_OS_...)
+ * @load_bug:	Place to decompress to
+ * @image_buf:	Address to decompress from
+ * @image_len:	Number of bytes in @image_buf to decompress
+ * @unc_len:	Available space for decompression
+ * @return 0 if OK, -ve on error (BOOTM_ERR_...)
+ */
+int bootm_decomp_image(int comp, ulong load, ulong image_start, int type,
+		       void *load_buf, void *image_buf, ulong image_len,
+		       uint unc_len, ulong *load_end);
+
 #endif