spl: Add methods to find the position/size of next phase

Binman supports writing the position and size of U-Boot proper and SPL
into the previous phase of U-Boot. This allows the next phase to be easily
located and loaded.

Add functions to return these useful values, along with symbols to allow
TPL to load SPL.
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NBin Meng <bmeng.cn@gmail.com>

common/spl/spl.c

@@ -42,6 +42,12 @@ u32 *boot_params_ptr = NULL;
 
 /* See spl.h for information about this */
 binman_sym_declare(ulong, u_boot_any, image_pos);
+binman_sym_declare(ulong, u_boot_any, size);
+
+#ifdef CONFIG_TPL
+binman_sym_declare(ulong, spl, image_pos);
+binman_sym_declare(ulong, spl, size);
+#endif
 
 /* Define board data structure */
 static bd_t bdata __attribute__ ((section(".data")));
@@ -120,6 +126,20 @@ void spl_fixup_fdt(void)
 #endif
 }
 
+ulong spl_get_image_pos(void)
+{
+	return spl_phase() == PHASE_TPL ?
+		binman_sym(ulong, spl, image_pos) :
+		binman_sym(ulong, u_boot_any, image_pos);
+}
+
+ulong spl_get_image_size(void)
+{
+	return spl_phase() == PHASE_TPL ?
+		binman_sym(ulong, spl, size) :
+		binman_sym(ulong, u_boot_any, size);
+}
+
 /*
  * Weak default function for board specific cleanup/preparation before
  * Linux boot. Some boards/platforms might not need it, so just provide

include/spl.h

@@ -169,10 +169,29 @@ struct spl_load_info {
  * We need to know the position of U-Boot in memory so we can jump to it. We
  * allow any U-Boot binary to be used (u-boot.bin, u-boot-nodtb.bin,
  * u-boot.img), hence the '_any'. These is no checking here that the correct
- * image is found. For * example if u-boot.img is used we don't check that
+ * image is found. For example if u-boot.img is used we don't check that
  * spl_parse_image_header() can parse a valid header.
+ *
+ * Similarly for SPL, so that TPL can jump to SPL.
  */
 binman_sym_extern(ulong, u_boot_any, image_pos);
+binman_sym_extern(ulong, u_boot_any, size);
+binman_sym_extern(ulong, spl, image_pos);
+binman_sym_extern(ulong, spl, size);
+
+/**
+ * spl_get_image_pos() - get the image position of the next phase
+ *
+ * This returns the image position to use to load the next phase of U-Boot
+ */
+ulong spl_get_image_pos(void);
+
+/**
+ * spl_get_image_size() - get the size of the next phase
+ *
+ * This returns the size to use to load the next phase of U-Boot
+ */
+ulong spl_get_image_size(void);
 
 /**
  * spl_load_simple_fit_skip_processing() - Hook to allow skipping the FIT