From 7e97a194aca03c6ff86f84e46e196f5c9ed5c32c Mon Sep 17 00:00:00 2001 From: Esben Haabendal Date: Tue, 30 Apr 2019 09:17:58 +0200 Subject: [PATCH] net: ll_temac: Allow configuration of IRQ coalescing This allows custom setup of IRQ coalescing for platforms using legacy platform_device. The irq timeout and count parameters can be used for tuning cpu load vs. latency. I have maintained the 0x00000400 bit in TX_CHNL_CTRL. It is specified as unused in the documentation I have available. It does not make any difference in the hardware I have available, so it is left in to not risk breaking other platforms where it might be used. Signed-off-by: Esben Haabendal Signed-off-by: David S. Miller --- drivers/net/ethernet/xilinx/ll_temac.h | 4 ++ drivers/net/ethernet/xilinx/ll_temac_main.c | 40 +++++++++++++------ include/linux/platform_data/xilinx-ll-temac.h | 5 +++ 3 files changed, 37 insertions(+), 12 deletions(-) diff --git a/drivers/net/ethernet/xilinx/ll_temac.h b/drivers/net/ethernet/xilinx/ll_temac.h index 990f9ed151b2..1aeda084b8f1 100644 --- a/drivers/net/ethernet/xilinx/ll_temac.h +++ b/drivers/net/ethernet/xilinx/ll_temac.h @@ -375,6 +375,10 @@ struct temac_local { int tx_bd_next; int tx_bd_tail; int rx_bd_ci; + + /* DMA channel control setup */ + u32 tx_chnl_ctrl; + u32 rx_chnl_ctrl; }; /* Wrappers for temac_ior()/temac_iow() function pointers above */ diff --git a/drivers/net/ethernet/xilinx/ll_temac_main.c b/drivers/net/ethernet/xilinx/ll_temac_main.c index fec8e4c22944..bccef30bf64e 100644 --- a/drivers/net/ethernet/xilinx/ll_temac_main.c +++ b/drivers/net/ethernet/xilinx/ll_temac_main.c @@ -304,18 +304,15 @@ static int temac_dma_bd_init(struct net_device *ndev) lp->rx_bd_v[i].app0 = cpu_to_be32(STS_CTRL_APP0_IRQONEND); } - lp->dma_out(lp, TX_CHNL_CTRL, 0x10220400 | - CHNL_CTRL_IRQ_EN | - CHNL_CTRL_IRQ_DLY_EN | - CHNL_CTRL_IRQ_COAL_EN); - /* 0x10220483 */ - /* 0x00100483 */ - lp->dma_out(lp, RX_CHNL_CTRL, 0xff070000 | - CHNL_CTRL_IRQ_EN | - CHNL_CTRL_IRQ_DLY_EN | - CHNL_CTRL_IRQ_COAL_EN | - CHNL_CTRL_IRQ_IOE); - /* 0xff010283 */ + /* Configure DMA channel (irq setup) */ + lp->dma_out(lp, TX_CHNL_CTRL, lp->tx_chnl_ctrl | + 0x00000400 | // Use 1 Bit Wide Counters. Currently Not Used! + CHNL_CTRL_IRQ_EN | CHNL_CTRL_IRQ_ERR_EN | + CHNL_CTRL_IRQ_DLY_EN | CHNL_CTRL_IRQ_COAL_EN); + lp->dma_out(lp, RX_CHNL_CTRL, lp->rx_chnl_ctrl | + CHNL_CTRL_IRQ_IOE | + CHNL_CTRL_IRQ_EN | CHNL_CTRL_IRQ_ERR_EN | + CHNL_CTRL_IRQ_DLY_EN | CHNL_CTRL_IRQ_COAL_EN); lp->dma_out(lp, RX_CURDESC_PTR, lp->rx_bd_p); lp->dma_out(lp, RX_TAILDESC_PTR, @@ -1191,6 +1188,13 @@ static int temac_probe(struct platform_device *pdev) lp->rx_irq = irq_of_parse_and_map(dma_np, 0); lp->tx_irq = irq_of_parse_and_map(dma_np, 1); + /* Use defaults for IRQ delay/coalescing setup. These + * are configuration values, so does not belong in + * device-tree. + */ + lp->tx_chnl_ctrl = 0x10220000; + lp->rx_chnl_ctrl = 0xff070000; + /* Finished with the DMA node; drop the reference */ of_node_put(dma_np); } else if (pdata) { @@ -1214,6 +1218,18 @@ static int temac_probe(struct platform_device *pdev) /* Get DMA RX and TX interrupts */ lp->rx_irq = platform_get_irq(pdev, 0); lp->tx_irq = platform_get_irq(pdev, 1); + + /* IRQ delay/coalescing setup */ + if (pdata->tx_irq_timeout || pdata->tx_irq_count) + lp->tx_chnl_ctrl = (pdata->tx_irq_timeout << 24) | + (pdata->tx_irq_count << 16); + else + lp->tx_chnl_ctrl = 0x10220000; + if (pdata->rx_irq_timeout || pdata->rx_irq_count) + lp->rx_chnl_ctrl = (pdata->rx_irq_timeout << 24) | + (pdata->rx_irq_count << 16); + else + lp->rx_chnl_ctrl = 0xff070000; } /* Error handle returned DMA RX and TX interrupts */ diff --git a/include/linux/platform_data/xilinx-ll-temac.h b/include/linux/platform_data/xilinx-ll-temac.h index b0b8238a9b7d..368530f98176 100644 --- a/include/linux/platform_data/xilinx-ll-temac.h +++ b/include/linux/platform_data/xilinx-ll-temac.h @@ -22,6 +22,11 @@ struct ll_temac_platform_data { * they share the same DCR bus bridge. */ struct mutex *indirect_mutex; + /* DMA channel control setup */ + u8 tx_irq_timeout; /* TX Interrupt Delay Time-out */ + u8 tx_irq_count; /* TX Interrupt Coalescing Threshold Count */ + u8 rx_irq_timeout; /* RX Interrupt Delay Time-out */ + u8 rx_irq_count; /* RX Interrupt Coalescing Threshold Count */ }; #endif /* __LINUX_XILINX_LL_TEMAC_H */ -- 2.30.2