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H A Dmain.cdiff 35af89eb491a0741005e474626053266e6e635b7 Tue Nov 21 01:37:37 CET 2006 David Gibson <david@gibson.dropbear.id.au> [POWERPC] Cleanup zImage handling of kernel entry with flat device tree

This makes 2 changes to clean up the flat device tree handling
logic in the zImage wrapper.

First, there were two callbacks from the dt_ops structure used for
producing a final flat tree to pass to the kerne: dt_ops.ft_pack()
which packed the flat tree (possibly a no-op) and dt_ops.ft_addr()
which retreived the address of the final blob. Since they were only
ever called together, this patch combines the two into a single new
callback, dt_ops.finalize(). This new callback does whatever
platform-dependent things are necessary to produce a final flat device
tree blob, and returns the blob's addres.

Second, the current logic calls the kernel with a flat device tree if
one is build into the zImage wrapper, otherwise it boots the kernel
with a PROM pointer, expecting the kernel to copy the OF device tree
itself. This approach precludes the possibility of the platform
wrapper code building a flat device tree from whatever
platform-specific information firmware provides. Thus, this patch
takes the more sensible approach of invoking the kernel with a flat
tree if the dt_ops.finalize callback provides one (by whatever means).

So, the dt_ops.finalize callback can be NULL, or can be a function
which returns NULL. In either case, the zImage wrapper logic assumes
that this is a platform with OF and invokes the kernel accordingly.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
H A Dops.hdiff 35af89eb491a0741005e474626053266e6e635b7 Tue Nov 21 01:37:37 CET 2006 David Gibson <david@gibson.dropbear.id.au> [POWERPC] Cleanup zImage handling of kernel entry with flat device tree

This makes 2 changes to clean up the flat device tree handling
logic in the zImage wrapper.

First, there were two callbacks from the dt_ops structure used for
producing a final flat tree to pass to the kerne: dt_ops.ft_pack()
which packed the flat tree (possibly a no-op) and dt_ops.ft_addr()
which retreived the address of the final blob. Since they were only
ever called together, this patch combines the two into a single new
callback, dt_ops.finalize(). This new callback does whatever
platform-dependent things are necessary to produce a final flat device
tree blob, and returns the blob's addres.

Second, the current logic calls the kernel with a flat device tree if
one is build into the zImage wrapper, otherwise it boots the kernel
with a PROM pointer, expecting the kernel to copy the OF device tree
itself. This approach precludes the possibility of the platform
wrapper code building a flat device tree from whatever
platform-specific information firmware provides. Thus, this patch
takes the more sensible approach of invoking the kernel with a flat
tree if the dt_ops.finalize callback provides one (by whatever means).

So, the dt_ops.finalize callback can be NULL, or can be a function
which returns NULL. In either case, the zImage wrapper logic assumes
that this is a platform with OF and invokes the kernel accordingly.

Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>