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-rw-r--r--README8
1 files changed, 8 insertions, 0 deletions
diff --git a/README b/README
index 81692c0..acb3308 100644
--- a/README
+++ b/README
@@ -4023,6 +4023,14 @@ On ARM, the following registers are used:
==> U-Boot will use R8 to hold a pointer to the global data
+On Nios II, the ABI is documented here:
+ http://www.altera.com/literature/hb/nios2/n2cpu_nii51016.pdf
+
+ ==> U-Boot will use gp to hold a pointer to the global data
+
+ Note: on Nios II, we give "-G0" option to gcc and don't use gp
+ to access small data sections, so gp is free.
+
NOTE: DECLARE_GLOBAL_DATA_PTR must be used with file-global scope,
or current versions of GCC may "optimize" the code too much.