From: Dale Farnsworth Date: Tue, 21 Mar 2006 18:44:35 +0000 (-0700) Subject: [PATCH] mv643xx_eth: Cache align skb->data if CONFIG_NOT_COHERENT_CACHE X-Git-Tag: v2.6.17-rc1~1164 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=6f059c3e9042bc4eaa4f7a8dd651bbed9be144f2;p=linux-2.6 [PATCH] mv643xx_eth: Cache align skb->data if CONFIG_NOT_COHERENT_CACHE When I/O is non-cache-coherent, we need to ensure that the I/O buffers we use don't share cache lines with other data. Signed-off-by: Dale Farnsworth Signed-off-by: Jeff Garzik --- diff --git a/drivers/net/mv643xx_eth.h b/drivers/net/mv643xx_eth.h index 7754d1974b..4262c1da6d 100644 --- a/drivers/net/mv643xx_eth.h +++ b/drivers/net/mv643xx_eth.h @@ -42,13 +42,23 @@ #define MAX_DESCS_PER_SKB 1 #endif +/* + * The MV643XX HW requires 8-byte alignment. However, when I/O + * is non-cache-coherent, we need to ensure that the I/O buffers + * we use don't share cache lines with other data. + */ +#if defined(CONFIG_DMA_NONCOHERENT) || defined(CONFIG_NOT_COHERENT_CACHE) +#define ETH_DMA_ALIGN L1_CACHE_BYTES +#else +#define ETH_DMA_ALIGN 8 +#endif + #define ETH_VLAN_HLEN 4 #define ETH_FCS_LEN 4 -#define ETH_DMA_ALIGN 8 /* hw requires 8-byte alignment */ -#define ETH_HW_IP_ALIGN 2 /* hw aligns IP header */ +#define ETH_HW_IP_ALIGN 2 /* hw aligns IP header */ #define ETH_WRAPPER_LEN (ETH_HW_IP_ALIGN + ETH_HLEN + \ - ETH_VLAN_HLEN + ETH_FCS_LEN) -#define ETH_RX_SKB_SIZE ((dev->mtu + ETH_WRAPPER_LEN + 7) & ~0x7) + ETH_VLAN_HLEN + ETH_FCS_LEN) +#define ETH_RX_SKB_SIZE (dev->mtu + ETH_WRAPPER_LEN + ETH_DMA_ALIGN) #define ETH_RX_QUEUES_ENABLED (1 << 0) /* use only Q0 for receive */ #define ETH_TX_QUEUES_ENABLED (1 << 0) /* use only Q0 for transmit */