From f080a8c35d8932d72c08df1260bbea14b7db481e Mon Sep 17 00:00:00 2001 From: Srikanth Thokala Date: Tue, 5 May 2015 11:25:57 +0200 Subject: [PATCH] net: axienet: Handle jumbo frames for lesser frame sizes In the current implementation, jumbo frames are supported only for the frame sizes > 16K. This patch corrects this logic to handle jumbo frames for lesser frame sizes (< 16K) ensuring jumbo frame MTU is within the limit of max frame size configured in the h/w design. Signed-off-by: Srikanth Thokala Signed-off-by: Michal Simek Signed-off-by: David S. Miller --- drivers/net/ethernet/xilinx/xilinx_axienet.h | 9 ++--- drivers/net/ethernet/xilinx/xilinx_axienet_main.c | 46 +++++++++++------------ 2 files changed, 27 insertions(+), 28 deletions(-) diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet.h b/drivers/net/ethernet/xilinx/xilinx_axienet.h index 4c9b4fa..4e30944 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet.h +++ b/drivers/net/ethernet/xilinx/xilinx_axienet.h @@ -11,16 +11,16 @@ #include #include #include +#include /* Packet size info */ #define XAE_HDR_SIZE 14 /* Size of Ethernet header */ -#define XAE_HDR_VLAN_SIZE 18 /* Size of an Ethernet hdr + VLAN */ #define XAE_TRL_SIZE 4 /* Size of Ethernet trailer (FCS) */ #define XAE_MTU 1500 /* Max MTU of an Ethernet frame */ #define XAE_JUMBO_MTU 9000 /* Max MTU of a jumbo Eth. frame */ #define XAE_MAX_FRAME_SIZE (XAE_MTU + XAE_HDR_SIZE + XAE_TRL_SIZE) -#define XAE_MAX_VLAN_FRAME_SIZE (XAE_MTU + XAE_HDR_VLAN_SIZE + XAE_TRL_SIZE) +#define XAE_MAX_VLAN_FRAME_SIZE (XAE_MTU + VLAN_ETH_HLEN + XAE_TRL_SIZE) #define XAE_MAX_JUMBO_FRAME_SIZE (XAE_JUMBO_MTU + XAE_HDR_SIZE + XAE_TRL_SIZE) /* Configuration options */ @@ -407,8 +407,7 @@ struct axidma_bd { * Txed/Rxed in the existing hardware. If jumbo option is * supported, the maximum frame size would be 9k. Else it is * 1522 bytes (assuming support for basic VLAN) - * @jumbo_support: Stores hardware configuration for jumbo support. If hardware - * can handle jumbo packets, this entry will be 1, else 0. + * @rxmem: Stores rx memory size for jumbo frame handling. */ struct axienet_local { struct net_device *ndev; @@ -446,7 +445,7 @@ struct axienet_local { u32 rx_bd_ci; u32 max_frm_size; - u32 jumbo_support; + u32 rxmem; int csum_offload_on_tx_path; int csum_offload_on_rx_path; diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index b834253..b1081e1 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -471,14 +471,16 @@ static void axienet_device_reset(struct net_device *ndev) __axienet_device_reset(lp, &ndev->dev, XAXIDMA_RX_CR_OFFSET); lp->max_frm_size = XAE_MAX_VLAN_FRAME_SIZE; + lp->options |= XAE_OPTION_VLAN; lp->options &= (~XAE_OPTION_JUMBO); if ((ndev->mtu > XAE_MTU) && - (ndev->mtu <= XAE_JUMBO_MTU) && - (lp->jumbo_support)) { - lp->max_frm_size = ndev->mtu + XAE_HDR_VLAN_SIZE + - XAE_TRL_SIZE; - lp->options |= XAE_OPTION_JUMBO; + (ndev->mtu <= XAE_JUMBO_MTU)) { + lp->max_frm_size = ndev->mtu + VLAN_ETH_HLEN + + XAE_TRL_SIZE; + + if (lp->max_frm_size <= lp->rxmem) + lp->options |= XAE_OPTION_JUMBO; } if (axienet_dma_bd_init(ndev)) { @@ -1027,15 +1029,15 @@ static int axienet_change_mtu(struct net_device *ndev, int new_mtu) if (netif_running(ndev)) return -EBUSY; - if (lp->jumbo_support) { - if ((new_mtu > XAE_JUMBO_MTU) || (new_mtu < 64)) - return -EINVAL; - ndev->mtu = new_mtu; - } else { - if ((new_mtu > XAE_MTU) || (new_mtu < 64)) - return -EINVAL; - ndev->mtu = new_mtu; - } + + if ((new_mtu + VLAN_ETH_HLEN + + XAE_TRL_SIZE) > lp->rxmem) + return -EINVAL; + + if ((new_mtu > XAE_JUMBO_MTU) || (new_mtu < 64)) + return -EINVAL; + + ndev->mtu = new_mtu; return 0; } @@ -1556,16 +1558,14 @@ static int axienet_of_probe(struct platform_device *op) } } /* For supporting jumbo frames, the Axi Ethernet hardware must have - * a larger Rx/Tx Memory. Typically, the size must be more than or - * equal to 16384 bytes, so that we can enable jumbo option and start - * supporting jumbo frames. Here we check for memory allocated for - * Rx/Tx in the hardware from the device-tree and accordingly set - * flags. */ + * a larger Rx/Tx Memory. Typically, the size must be large so that + * we can enable jumbo option and start supporting jumbo frames. + * Here we check for memory allocated for Rx/Tx in the hardware from + * the device-tree and accordingly set flags. + */ p = (__be32 *) of_get_property(op->dev.of_node, "xlnx,rxmem", NULL); - if (p) { - if ((be32_to_cpup(p)) >= 0x4000) - lp->jumbo_support = 1; - } + if (p) + lp->rxmem = be32_to_cpup(p); p = (__be32 *) of_get_property(op->dev.of_node, "xlnx,phy-type", NULL); if (p) lp->phy_type = be32_to_cpup(p); -- 2.7.4