From 015dac8886b5c48d62ebc33a964b9086d6a71bd7 Mon Sep 17 00:00:00 2001 From: Michael Hennerich Date: Fri, 29 May 2009 03:41:15 +0000 Subject: [PATCH 1/1] netdev: bfin_mac: fix performance issue found by netperf - Remove dead long delay - Use proper defines - Remove broken implementation of the TX DMA Data Alignment TXDWA feature Signed-off-by: Michael Hennerich Signed-off-by: Mike Frysinger Signed-off-by: Bryan Wu Signed-off-by: David S. Miller --- drivers/net/bfin_mac.c | 110 ++++++++++++------------------------------------- 1 file changed, 26 insertions(+), 84 deletions(-) diff --git a/drivers/net/bfin_mac.c b/drivers/net/bfin_mac.c index 38d34ce..f0f1eb9 100644 --- a/drivers/net/bfin_mac.c +++ b/drivers/net/bfin_mac.c @@ -194,13 +194,13 @@ static int desc_list_init(void) struct dma_descriptor *b = &(r->desc_b); /* allocate a new skb for next time receive */ - new_skb = dev_alloc_skb(PKT_BUF_SZ + 2); + new_skb = dev_alloc_skb(PKT_BUF_SZ + NET_IP_ALIGN); if (!new_skb) { printk(KERN_NOTICE DRV_NAME ": init: low on mem - packet dropped\n"); goto init_error; } - skb_reserve(new_skb, 2); + skb_reserve(new_skb, NET_IP_ALIGN); r->skb = new_skb; /* @@ -566,9 +566,9 @@ static void adjust_tx_list(void) */ if (current_tx_ptr->next->next == tx_list_head) { while (tx_list_head->status.status_word == 0) { - mdelay(1); + udelay(10); if (tx_list_head->status.status_word != 0 - || !(bfin_read_DMA2_IRQ_STATUS() & 0x08)) { + || !(bfin_read_DMA2_IRQ_STATUS() & DMA_RUN)) { goto adjust_head; } if (timeout_cnt-- < 0) { @@ -606,86 +606,28 @@ static int bfin_mac_hard_start_xmit(struct sk_buff *skb, struct net_device *dev) { u16 *data; - + u32 data_align = (unsigned long)(skb->data) & 0x3; current_tx_ptr->skb = skb; - if (ANOMALY_05000285) { - /* - * TXDWA feature is not avaible to older revision < 0.3 silicon - * of BF537 - * - * Only if data buffer is ODD WORD alignment, we do not - * need to memcpy - */ - u32 data_align = (u32)(skb->data) & 0x3; - if (data_align == 0x2) { - /* move skb->data to current_tx_ptr payload */ - data = (u16 *)(skb->data) - 1; - *data = (u16)(skb->len); - current_tx_ptr->desc_a.start_addr = (u32)data; - /* this is important! */ - blackfin_dcache_flush_range((u32)data, - (u32)((u8 *)data + skb->len + 4)); - } else { - *((u16 *)(current_tx_ptr->packet)) = (u16)(skb->len); - memcpy((u8 *)(current_tx_ptr->packet + 2), skb->data, - skb->len); - current_tx_ptr->desc_a.start_addr = - (u32)current_tx_ptr->packet; - if (current_tx_ptr->status.status_word != 0) - current_tx_ptr->status.status_word = 0; - blackfin_dcache_flush_range( - (u32)current_tx_ptr->packet, - (u32)(current_tx_ptr->packet + skb->len + 2)); - } + if (data_align == 0x2) { + /* move skb->data to current_tx_ptr payload */ + data = (u16 *)(skb->data) - 1; + *data = (u16)(skb->len); + current_tx_ptr->desc_a.start_addr = (u32)data; + /* this is important! */ + blackfin_dcache_flush_range((u32)data, + (u32)((u8 *)data + skb->len + 4)); } else { - /* - * TXDWA feature is avaible to revision < 0.3 silicon of - * BF537 and always avaible to BF52x - */ - u32 data_align = (u32)(skb->data) & 0x3; - if (data_align == 0x0) { - u16 sysctl = bfin_read_EMAC_SYSCTL(); - sysctl |= TXDWA; - bfin_write_EMAC_SYSCTL(sysctl); - - /* move skb->data to current_tx_ptr payload */ - data = (u16 *)(skb->data) - 2; - *data = (u16)(skb->len); - current_tx_ptr->desc_a.start_addr = (u32)data; - /* this is important! */ - blackfin_dcache_flush_range( - (u32)data, - (u32)((u8 *)data + skb->len + 4)); - } else if (data_align == 0x2) { - u16 sysctl = bfin_read_EMAC_SYSCTL(); - sysctl &= ~TXDWA; - bfin_write_EMAC_SYSCTL(sysctl); - - /* move skb->data to current_tx_ptr payload */ - data = (u16 *)(skb->data) - 1; - *data = (u16)(skb->len); - current_tx_ptr->desc_a.start_addr = (u32)data; - /* this is important! */ - blackfin_dcache_flush_range( - (u32)data, - (u32)((u8 *)data + skb->len + 4)); - } else { - u16 sysctl = bfin_read_EMAC_SYSCTL(); - sysctl &= ~TXDWA; - bfin_write_EMAC_SYSCTL(sysctl); - - *((u16 *)(current_tx_ptr->packet)) = (u16)(skb->len); - memcpy((u8 *)(current_tx_ptr->packet + 2), skb->data, - skb->len); - current_tx_ptr->desc_a.start_addr = - (u32)current_tx_ptr->packet; - if (current_tx_ptr->status.status_word != 0) - current_tx_ptr->status.status_word = 0; - blackfin_dcache_flush_range( - (u32)current_tx_ptr->packet, - (u32)(current_tx_ptr->packet + skb->len + 2)); - } + *((u16 *)(current_tx_ptr->packet)) = (u16)(skb->len); + memcpy((u8 *)(current_tx_ptr->packet + 2), skb->data, + skb->len); + current_tx_ptr->desc_a.start_addr = + (u32)current_tx_ptr->packet; + if (current_tx_ptr->status.status_word != 0) + current_tx_ptr->status.status_word = 0; + blackfin_dcache_flush_range( + (u32)current_tx_ptr->packet, + (u32)(current_tx_ptr->packet + skb->len + 2)); } /* make sure the internal data buffers in the core are drained @@ -698,7 +640,7 @@ static int bfin_mac_hard_start_xmit(struct sk_buff *skb, current_tx_ptr->desc_a.config |= DMAEN; /* tx dma is running, just return */ - if (bfin_read_DMA2_IRQ_STATUS() & 0x08) + if (bfin_read_DMA2_IRQ_STATUS() & DMA_RUN) goto out; /* tx dma is not running */ @@ -724,7 +666,7 @@ static void bfin_mac_rx(struct net_device *dev) /* allocate a new skb for next time receive */ skb = current_rx_ptr->skb; - new_skb = dev_alloc_skb(PKT_BUF_SZ + 2); + new_skb = dev_alloc_skb(PKT_BUF_SZ + NET_IP_ALIGN); if (!new_skb) { printk(KERN_NOTICE DRV_NAME ": rx: low on mem - packet dropped\n"); @@ -732,7 +674,7 @@ static void bfin_mac_rx(struct net_device *dev) goto out; } /* reserve 2 bytes for RXDWA padding */ - skb_reserve(new_skb, 2); + skb_reserve(new_skb, NET_IP_ALIGN); current_rx_ptr->skb = new_skb; current_rx_ptr->desc_a.start_addr = (unsigned long)new_skb->data - 2; -- 1.8.2.3