diff options
| author | Joakim Tjernlund <Joakim.Tjernlund@transmode.se> | 2010-01-19 14:41:58 +0100 |
|---|---|---|
| committer | Wolfgang Denk <wd@denx.de> | 2010-01-26 19:30:15 +0100 |
| commit | e6bee80814c3a0d7eab89d28142fe68c4a670f31 (patch) | |
| tree | 78622a77e356e93dd3fed7c4728b776358c7b2f0 | |
| parent | 0f8aa159175385ddd77bc91d11b9568583fbbd0c (diff) | |
ppc: Update README about the new GOT ptr.
r14 is no longer used as non volatile GOT ptr. Instead
the volatile r12 is used so be sure to do GET_GOT in
asm code when you need to access global data.
Signed-off-by: Joakim Tjernlund <Joakim.Tjernlund@transmode.se>
| -rw-r--r-- | README | 4 |
1 files changed, 3 insertions, 1 deletions
@@ -3922,7 +3922,9 @@ For PowerPC, the following registers have specific use: R30: GOT pointer R31: frame pointer - (U-Boot also uses R14 as internal GOT pointer.) + (U-Boot also uses R12 as internal GOT pointer. r12 + is a volatile register so r12 needs to be reset when + going back and forth between asm and C) ==> U-Boot will use R2 to hold a pointer to the global data |