As part of the FF-A spec, an endpoint is allowed to transfer access of,
or lend, a memory region to one or more borrowers.
Extend the existing memory sharing implementation to support
FF-A MEM_LEND functionality and expose this to other kernel drivers.
Note that upon a successful MEM_LEND request the caller must ensure that
the memory region specified is not accessed until a successful
MEM_RECALIM call has been made. On systems with a hypervisor present
this will been enforced, however on systems without a hypervisor the
responsibility falls to the calling kernel driver to prevent access.
Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Jens Wiklander <[email protected]>
Signed-off-by: Marc Bonnici <[email protected]>
Signed-off-by: Sudeep Holla <[email protected]>
Most of the MEM_* APIs share the same parameters, so they can be
generalised. Currently only MEM_SHARE is implemented and the user space
interface for that is not added yet.
Link: https://lore.kernel.org/r/[email protected]
Tested-by: Jens Wiklander <[email protected]>
Signed-off-by: Sudeep Holla <[email protected]>
Parse the FFA nodes from the device-tree and register all the partitions
whose services will be used in the kernel.
In order to also enable in-kernel users of FFA interface, let us add
simple set of operations for such devices.
The in-kernel users are registered without the character device interface.
Link: https://lore.kernel.org/r/[email protected]
Tested-by: Jens Wiklander <[email protected]>
Reviewed-by: Jens Wiklander <[email protected]>
Signed-off-by: Sudeep Holla <[email protected]>
The Arm FF for Armv8-A specification has concept of endpoints or
partitions. In the Normal world, a partition could be a VM when
the Virtualization extension is enabled or the kernel itself.
In order to handle multiple partitions, we can create a FFA device for
each such partition on a dedicated FFA bus. Similarly, different drivers
requiring FFA transport can be registered on the same bus. We can match
the device and drivers using UUID. This is mostly for the in-kernel
users with FFA drivers.
Link: https://lore.kernel.org/r/[email protected]
Tested-by: Jens Wiklander <[email protected]>
Signed-off-by: Sudeep Holla <[email protected]>
Sudeep Holla