From: Bruce Allan Date: Fri, 15 Dec 2006 09:39:45 +0000 (+0100) Subject: [PATCH] e1000: Fix PBA allocation calculations X-Git-Tag: v2.6.20-rc3~56^2~28 X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=018ea44ef1eade417296c4a57afe3cd963268433;p=linux-2.6 [PATCH] e1000: Fix PBA allocation calculations Assign the PBA to be large enough to contain at least 2 jumbo frames on all adapters. This dramatically increases performance on several adapters and fixes TX performance degradation issues where the PBA was misallocated in the old algorithm. Signed-off-by: Bruce Allan Signed-off-by: Auke Kok Signed-off-by: Arjan van de Ven Signed-off-by: Jeff Garzik --- diff --git a/drivers/net/e1000/e1000_hw.h b/drivers/net/e1000/e1000_hw.h index f4d01e169c..15b8625c40 100644 --- a/drivers/net/e1000/e1000_hw.h +++ b/drivers/net/e1000/e1000_hw.h @@ -2422,6 +2422,7 @@ struct e1000_host_command_info { #define E1000_PBA_8K 0x0008 /* 8KB, default Rx allocation */ #define E1000_PBA_12K 0x000C /* 12KB, default Rx allocation */ #define E1000_PBA_16K 0x0010 /* 16KB, default TX allocation */ +#define E1000_PBA_20K 0x0014 #define E1000_PBA_22K 0x0016 #define E1000_PBA_24K 0x0018 #define E1000_PBA_30K 0x001E diff --git a/drivers/net/e1000/e1000_main.c b/drivers/net/e1000/e1000_main.c index e04f1ba847..6c3618d55d 100644 --- a/drivers/net/e1000/e1000_main.c +++ b/drivers/net/e1000/e1000_main.c @@ -661,16 +661,34 @@ e1000_reinit_locked(struct e1000_adapter *adapter) void e1000_reset(struct e1000_adapter *adapter) { - uint32_t pba; + uint32_t pba = 0, tx_space, min_tx_space, min_rx_space; uint16_t fc_high_water_mark = E1000_FC_HIGH_DIFF; + boolean_t legacy_pba_adjust = FALSE; /* Repartition Pba for greater than 9k mtu * To take effect CTRL.RST is required. */ switch (adapter->hw.mac_type) { + case e1000_82542_rev2_0: + case e1000_82542_rev2_1: + case e1000_82543: + case e1000_82544: + case e1000_82540: + case e1000_82541: + case e1000_82541_rev_2: + legacy_pba_adjust = TRUE; + pba = E1000_PBA_48K; + break; + case e1000_82545: + case e1000_82545_rev_3: + case e1000_82546: + case e1000_82546_rev_3: + pba = E1000_PBA_48K; + break; case e1000_82547: case e1000_82547_rev_2: + legacy_pba_adjust = TRUE; pba = E1000_PBA_30K; break; case e1000_82571: @@ -679,27 +697,80 @@ e1000_reset(struct e1000_adapter *adapter) pba = E1000_PBA_38K; break; case e1000_82573: - pba = E1000_PBA_12K; + pba = E1000_PBA_20K; break; case e1000_ich8lan: pba = E1000_PBA_8K; - break; - default: - pba = E1000_PBA_48K; + case e1000_undefined: + case e1000_num_macs: break; } - if ((adapter->hw.mac_type != e1000_82573) && - (adapter->netdev->mtu > E1000_RXBUFFER_8192)) - pba -= 8; /* allocate more FIFO for Tx */ + if (legacy_pba_adjust == TRUE) { + if (adapter->netdev->mtu > E1000_RXBUFFER_8192) + pba -= 8; /* allocate more FIFO for Tx */ + if (adapter->hw.mac_type == e1000_82547) { + adapter->tx_fifo_head = 0; + adapter->tx_head_addr = pba << E1000_TX_HEAD_ADDR_SHIFT; + adapter->tx_fifo_size = + (E1000_PBA_40K - pba) << E1000_PBA_BYTES_SHIFT; + atomic_set(&adapter->tx_fifo_stall, 0); + } + } else if (adapter->hw.max_frame_size > MAXIMUM_ETHERNET_FRAME_SIZE) { + /* adjust PBA for jumbo frames */ + E1000_WRITE_REG(&adapter->hw, PBA, pba); + + /* To maintain wire speed transmits, the Tx FIFO should be + * large enough to accomodate two full transmit packets, + * rounded up to the next 1KB and expressed in KB. Likewise, + * the Rx FIFO should be large enough to accomodate at least + * one full receive packet and is similarly rounded up and + * expressed in KB. */ + pba = E1000_READ_REG(&adapter->hw, PBA); + /* upper 16 bits has Tx packet buffer allocation size in KB */ + tx_space = pba >> 16; + /* lower 16 bits has Rx packet buffer allocation size in KB */ + pba &= 0xffff; + /* don't include ethernet FCS because hardware appends/strips */ + min_rx_space = adapter->netdev->mtu + ENET_HEADER_SIZE + + VLAN_TAG_SIZE; + min_tx_space = min_rx_space; + min_tx_space *= 2; + E1000_ROUNDUP(min_tx_space, 1024); + min_tx_space >>= 10; + E1000_ROUNDUP(min_rx_space, 1024); + min_rx_space >>= 10; + + /* If current Tx allocation is less than the min Tx FIFO size, + * and the min Tx FIFO size is less than the current Rx FIFO + * allocation, take space away from current Rx allocation */ + if (tx_space < min_tx_space && + ((min_tx_space - tx_space) < pba)) { + pba = pba - (min_tx_space - tx_space); + + /* PCI/PCIx hardware has PBA alignment constraints */ + switch (adapter->hw.mac_type) { + case e1000_82545 ... e1000_82546_rev_3: + pba &= ~(E1000_PBA_8K - 1); + break; + default: + break; + } - if (adapter->hw.mac_type == e1000_82547) { - adapter->tx_fifo_head = 0; - adapter->tx_head_addr = pba << E1000_TX_HEAD_ADDR_SHIFT; - adapter->tx_fifo_size = - (E1000_PBA_40K - pba) << E1000_PBA_BYTES_SHIFT; - atomic_set(&adapter->tx_fifo_stall, 0); + /* if short on rx space, rx wins and must trump tx + * adjustment or use Early Receive if available */ + if (pba < min_rx_space) { + switch (adapter->hw.mac_type) { + case e1000_82573: + /* ERT enabled in e1000_configure_rx */ + break; + default: + pba = min_rx_space; + break; + } + } + } } E1000_WRITE_REG(&adapter->hw, PBA, pba);