diff options
| author | Wolfgang Denk <wd@denx.de> | 2008-02-14 22:43:22 +0100 |
|---|---|---|
| committer | Wolfgang Denk <wd@denx.de> | 2008-02-14 22:43:22 +0100 |
| commit | e7670f6c1e52ae6d2a43ff75a8bcfa7a5c86e47b (patch) | |
| tree | c105ae64bb203f93e670ef11b3256a4a3086c0ad /README | |
| parent | 3c234efa693bc59906c2be55c7918ecbb55392ea (diff) | |
PPC: Use r2 instead of r29 as global data pointer
R29 was an unlucky choice as with recent toolchains (gcc-4.2.x) gcc
will refuse to use load/store multiple insns; instead, it issues a
list of simple load/store instructions upon function entry and exit,
resulting in bigger code size, which in turn makes the build for a
few boards fail.
Use r2 instead.
Signed-off-by: Wolfgang Denk <wd@denx.de>
Diffstat (limited to 'README')
| -rw-r--r-- | README | 4 |
1 files changed, 2 insertions, 2 deletions
@@ -3499,7 +3499,7 @@ GCC's implementation. For PowerPC, the following registers have specific use: R1: stack pointer - R2: TOC pointer + R2: reserved for system use R3-R4: parameter passing and return values R5-R10: parameter passing R13: small data area pointer @@ -3508,7 +3508,7 @@ For PowerPC, the following registers have specific use: (U-Boot also uses R14 as internal GOT pointer.) - ==> U-Boot will use R29 to hold a pointer to the global data + ==> U-Boot will use R2 to hold a pointer to the global data Note: on PPC, we could use a static initializer (since the address of the global data structure is known at compile time), |