Commit e80094a4 authored by Jakub Kicinski's avatar Jakub Kicinski Committed by David S. Miller
Browse files

ethernet: add a helper for assigning port addresses 



We have 5 drivers which offset base MAC addr by port id.
Create a helper for them.

This helper takes care of overflows, which some drivers
did not do, please complain if that's going to break
anything!

Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
Reviewed-by: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: default avatarShannon Nelson <snelson@pensando.io>
Reviewed-by: default avatarIdo Schimmel <idosch@nvidia.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 867a9284

include/linux/etherdevice.h

+21 −0
Original line number Diff line number Diff line
@@ -551,6 +551,27 @@ static inline unsigned long compare_ether_header(const void *a, const void *b) 
#endif

}



/**

 * eth_hw_addr_gen - Generate and assign Ethernet address to a port

 * @dev: pointer to port's net_device structure

 * @base_addr: base Ethernet address

 * @id: offset to add to the base address

 *

 * Generate a MAC address using a base address and an offset and assign it

 * to a net_device. Commonly used by switch drivers which need to compute

 * addresses for all their ports. addr_assign_type is not changed.

 */

static inline void eth_hw_addr_gen(struct net_device *dev, const u8 *base_addr,

				   unsigned int id)

{

	u64 u = ether_addr_to_u64(base_addr);

	u8 addr[ETH_ALEN];



	u += id;

	u64_to_ether_addr(u, addr);

	eth_hw_addr_set(dev, addr);

}



/**

 * eth_skb_pad - Pad buffer to mininum number of octets for Ethernet frame

 * @skb: Buffer to pad