Re: r8169 with big-endian (patch)

[Francois Romieu <romieu@fr.zoreil.com>]

Greetings,

Alexandra N. Kossovsky <sasha@oktet.ru> :
[...]
> Here is the patch to make RTL-8169 PCI Gbit ethernet card to work with
> big-endian host. The patch is against 2.4.22 kernel.

Please Cc: such patches to netdev@oss.sgi.com as well as jgarzik@pobox.com.

[...]
> @@ -664,19 +675,21 @@
>  	}
>  
>  	tp->TxDescArrays =
> -	    kmalloc(NUM_TX_DESC * sizeof (struct TxDesc) + 256, GFP_KERNEL);
> +	    pci_alloc_consistent(tp->pci_dev,
> +				 NUM_TX_DESC * sizeof (struct TxDesc) + 256, 
> +				 &tp->TxDescDmaAddrs);
> -	TxPhyAddr = virt_to_bus(tp->TxDescArrays);
> -	diff = 256 - (TxPhyAddr - ((TxPhyAddr >> 8) << 8));
> -	TxPhyAddr += diff;
> +	diff = 256 - (tp->TxDescDmaAddrs - ((tp->TxDescDmaAddrs >> 8) << 8));
> +	tp->TxDescDmaAddr = tp->TxDescDmaAddrs + diff;
>  	tp->TxDescArray = (struct TxDesc *) (tp->TxDescArrays + diff);

Remove the alignment stuff. pci_alloc_consistent() does it for you,
see Documentation/DMA-mapping.txt:
[...]
The cpu return address and the DMA bus master address are both
guaranteed to be aligned to the smallest PAGE_SIZE order which
is greater than or equal to the requested size.  This invariant


@@ -684,12 +697,18 @@
[...]
-       tp->RxBufferRings = kmalloc(RX_BUF_SIZE * NUM_RX_DESC, GFP_KERNEL);
+       tp->RxBufferRings = pci_alloc_consistent(tp->pci_dev,
+                                                RX_BUF_SIZE * NUM_RX_DESC,
+                                                &tp->RxBufferDmas);

You don't want consistent mapping for the data buffer.
Either you pci_map_single() the whole kmalloced() area and you sync it
when needed or you turn this code into usual, per skb, pci_map_single()
calls and you remove the big Rx data buffer.

--
Ueimor