[U-Boot] [PATCH v3 10/21] spl: Add a comment to spl_set_bd()

[Simon Glass]

There is a strange feature to set global_data to a data-section variable
early in SPL. This only works if SPL actually has access to SRAM which is
not the case on x86, for eaxmple. Add a comment to this effect.

Reviewed-by: Simon Glass <sjg at chromium.org>
Signed-off-by: Simon Glass <sjg at chromium.org>
---

Changes in v3: None
Changes in v2: None

 common/spl/spl.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/common/spl/spl.c b/common/spl/spl.c
index 5a026b844e9..43137105bab 100644
--- a/common/spl/spl.c
+++ b/common/spl/spl.c
@@ -378,6 +378,10 @@ static int spl_common_init(bool setup_malloc)
 
 void spl_set_bd(void)
 {
+	/*
+	 * NOTE: On some platforms (e.g. x86) bdata may be in flash and not
+	 * writeable.
+	 */
 	if (!gd->bd)
 		gd->bd = &bdata;
 }
-- 
2.19.1.1215.g8438c0b245-goog