NOR: add FIXMEs for writing ones

It can invalidate ECC codes, and in general is not guaranteed
to work.  (However on some chips it _appears_ to behave.)  Just
don't do it; don't write in those cases.

Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>

1 files changed, 6 insertions, 0 deletions

diff --git a/TODO b/TODO
index 8fed264b..73e4aa7b 100644
--- a/TODO
+++ b/TODO
@@ -209,6 +209,12 @@ https://lists.berlios.de/pipermail/openocd-development/2009-October/011506.html
   - ocl
   - str9xpec
 
+- Don't expect writing all-ones to be a safe way to write without
+  changing bit values.  Minimally it loses on flash modules with
+  internal ECC, where it may change the ECC.
+  - NOR flash_write_unlock() does that between sectors
+  - there may be other cases too
+
 @subsection thelistflashcfi CFI
 
 - finish implementing bus width/chip width handling (suggested by NC)