efi_loader: Fix network DP with DM_ETH

When CONFIG_DM_ETH is set, we assemble the device path properly with a
full device hierarchy. Our helper function dp_fill() even put the MAC
node itself in it for us.

However, for non-DM compatibility we also have code in that added the
MAC node manually. That code now runs on top of the existing MAC node:

  Handle 0x3db2f6b0
    /HardwareVendor(e61d73b9-a384-4acc-aeab-82e828f3628b)[0: ]
    /USBClass(0,0,9,0,0)/USBClass(424,9514,9,0,2)/MacAddr(b8:27:eb:e1:81:47,1)
    /MacAddr(b8:27:eb:e1:81:47,57)/EndEntire

We obviously don't need the additional node and in fact, grub chokes on
it and fails to match the DP against the ethernet device node. So this
patch moves the additional MAC node into the non-DM code path:

  Handle 0x3db3fde0
    /HardwareVendor(e61d73b9-a384-4acc-aeab-82e828f3628b)[0: ]
    /USBClass(0,0,9,0,0)/USBClass(424,9514,9,0,2)/MacAddr(b8:27:eb:e1:81:47,1)
    /EndEntire

While at it, we also mark the non-DM MAC node as ethernet.

Fixes: b66c60dde9 ("efi_loader: add device-path utils")
Signed-off-by: Alexander Graf <agraf@suse.de>

lib/efi_loader/efi_device_path.c

@@ -749,7 +749,9 @@ struct efi_device_path *efi_dp_from_file(struct blk_desc *desc, int part,
 #ifdef CONFIG_CMD_NET
 struct efi_device_path *efi_dp_from_eth(void)
 {
+#ifndef CONFIG_DM_ETH
 	struct efi_device_path_mac_addr *ndp;
+#endif
 	void *buf, *start;
 	unsigned dpsize = 0;
 
@@ -759,8 +761,8 @@ struct efi_device_path *efi_dp_from_eth(void)
 	dpsize += dp_size(eth_get_dev());
 #else
 	dpsize += sizeof(ROOT);
-#endif
 	dpsize += sizeof(*ndp);
+#endif
 
 	start = buf = dp_alloc(dpsize + sizeof(END));
 	if (!buf)
@@ -771,14 +773,15 @@ struct efi_device_path *efi_dp_from_eth(void)
 #else
 	memcpy(buf, &ROOT, sizeof(ROOT));
 	buf += sizeof(ROOT);
-#endif
 
 	ndp = buf;
 	ndp->dp.type = DEVICE_PATH_TYPE_MESSAGING_DEVICE;
 	ndp->dp.sub_type = DEVICE_PATH_SUB_TYPE_MSG_MAC_ADDR;
 	ndp->dp.length = sizeof(*ndp);
+	ndp->if_type = 1; /* Ethernet */
 	memcpy(ndp->mac.addr, eth_get_ethaddr(), ARP_HLEN);
 	buf = &ndp[1];
+#endif
 
 	*((struct efi_device_path *)buf) = END;