common: Rewrite hiding the end of memory
As the name may be confusing, the CONFIG_SYS_MEM_TOP_HIDE reserves
some memory from the end of ram, tracked by gd->ram_size. It is not
always the top of u-boot visible memory. Rewrite the macro with a
weak function to provide flexibility for complex calcuation. Legacy
use of this macro is still supported.
Signed-off-by: York Sun <yorksun@freescale.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/README b/README
index 6ea1af2..4aa2aae 100644
--- a/README
+++ b/README
@@ -3877,7 +3877,7 @@
the RAM base is not zero, or RAM is divided into banks,
this variable needs to be recalcuated to get the address.
-- CONFIG_SYS_MEM_TOP_HIDE (PPC only):
+- CONFIG_SYS_MEM_TOP_HIDE:
If CONFIG_SYS_MEM_TOP_HIDE is defined in the board config header,
this specified memory area will get subtracted from the top
(end) of RAM and won't get "touched" at all by U-Boot. By