Commit a036119f authored by Stephen Hemminger's avatar Stephen Hemminger Committed by Jeff Garzik
Browse files

[PATCH] sky2: optimize for 32 bit dma 



Small optimization, if dma addresses are 32 bits, then high
bits are always zero.

Signed-off-by: default avatarStephen Hemminger <shemminger@osdl.or>
Signed-off-by: default avatarJeff Garzik <jgarzik@pobox.com>
parent dc4d5ea2

drivers/net/sky2.c

+2 −2
Original line number Diff line number Diff line
@@ -745,7 +745,7 @@ static inline struct sky2_rx_le *sky2_next_rx(struct sky2_port *sky2) 
/* Return high part of DMA address (could be 32 or 64 bit) */

static inline u32 high32(dma_addr_t a)

{

	return (a >> 16) >> 16;

	return sizeof(a) > sizeof(u32) ? (a >> 16) >> 16 : 0;

}



/* Build description to hardware about buffer */
@@ -1225,7 +1225,7 @@ static int sky2_xmit_frame(struct sk_buff *skb, struct net_device *dev) 


		mapping = pci_map_page(hw->pdev, frag->page, frag->page_offset,

				       frag->size, PCI_DMA_TODEVICE);

		addr64 = (mapping >> 16) >> 16;

		addr64 = high32(mapping);

		if (addr64 != sky2->tx_addr64) {

			le = get_tx_le(sky2);

			le->tx.addr = cpu_to_le32(addr64);