From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933901AbdCJQhf (ORCPT ); Fri, 10 Mar 2017 11:37:35 -0500 Received: from mail-wm0-f66.google.com ([74.125.82.66]:33019 "EHLO mail-wm0-f66.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933235AbdCJQfT (ORCPT ); Fri, 10 Mar 2017 11:35:19 -0500 From: Thierry Reding To: "David S . Miller" Cc: Giuseppe Cavallaro , Alexandre Torgue , Joao Pinto , Jon Hunter , Mikko Perttunen , netdev@vger.kernel.org, linux-tegra@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v2 7/9] net: stmmac: Program RX queue size and flow control Date: Fri, 10 Mar 2017 17:34:59 +0100 Message-Id: <20170310163501.31811-8-thierry.reding@gmail.com> X-Mailer: git-send-email 2.12.0 In-Reply-To: <20170310163501.31811-1-thierry.reding@gmail.com> References: <20170310163501.31811-1-thierry.reding@gmail.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Thierry Reding Program the receive queue size based on the RX FIFO size and enable hardware flow control for large FIFOs. Signed-off-by: Thierry Reding --- Changes in v2: - add comments to clarify flow control threshold programming drivers/net/ethernet/stmicro/stmmac/dwmac4.h | 12 ++++++ drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c | 52 +++++++++++++++++++++++- 2 files changed, 62 insertions(+), 2 deletions(-) diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h index 83f5e953e291..3b1828b4d294 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4.h +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4.h @@ -182,6 +182,7 @@ enum power_event { #define MTL_OP_MODE_TSF BIT(1) #define MTL_OP_MODE_TQS_MASK GENMASK(24, 16) +#define MTL_OP_MODE_TQS_SHIFT 16 #define MTL_OP_MODE_TTC_MASK 0x70 #define MTL_OP_MODE_TTC_SHIFT 4 @@ -195,6 +196,17 @@ enum power_event { #define MTL_OP_MODE_TTC_384 (6 << MTL_OP_MODE_TTC_SHIFT) #define MTL_OP_MODE_TTC_512 (7 << MTL_OP_MODE_TTC_SHIFT) +#define MTL_OP_MODE_RQS_MASK GENMASK(29, 20) +#define MTL_OP_MODE_RQS_SHIFT 20 + +#define MTL_OP_MODE_RFD_MASK GENMASK(19, 14) +#define MTL_OP_MODE_RFD_SHIFT 14 + +#define MTL_OP_MODE_RFA_MASK GENMASK(13, 8) +#define MTL_OP_MODE_RFA_SHIFT 8 + +#define MTL_OP_MODE_EHFC BIT(7) + #define MTL_OP_MODE_RTC_MASK 0x18 #define MTL_OP_MODE_RTC_SHIFT 3 diff --git a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c index 55270933bae1..6ac6b2600a7c 100644 --- a/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c +++ b/drivers/net/ethernet/stmicro/stmmac/dwmac4_dma.c @@ -183,8 +183,9 @@ static void dwmac4_rx_watchdog(void __iomem *ioaddr, u32 riwt) } static void dwmac4_dma_chan_op_mode(void __iomem *ioaddr, int txmode, - int rxmode, u32 channel) + int rxmode, u32 channel, int rxfifosz) { + unsigned int rqs = rxfifosz / 256 - 1; u32 mtl_tx_op, mtl_rx_op, mtl_rx_int; /* Following code only done for channel 0, other channels not yet @@ -250,6 +251,53 @@ static void dwmac4_dma_chan_op_mode(void __iomem *ioaddr, int txmode, mtl_rx_op |= MTL_OP_MODE_RTC_128; } + mtl_rx_op &= ~MTL_OP_MODE_RQS_MASK; + mtl_rx_op |= rqs << MTL_OP_MODE_RQS_SHIFT; + + /* enable flow control only if each channel gets 4 KiB or more FIFO */ + if (rxfifosz >= 4096) { + unsigned int rfd, rfa; + + mtl_rx_op |= MTL_OP_MODE_EHFC; + + /* Set Threshold for Activating Flow Control to min 2 frames, + * i.e. 1500 * 2 = 3000 bytes. + * + * Set Threshold for Deactivating Flow Control to min 1 frame, + * i.e. 1500 bytes. + */ + switch (rxfifosz) { + case 4096: + /* This violates the above formula because of FIFO size + * limit therefore overflow may occur in spite of this. + */ + rfd = 0x03; /* Full-2.5K */ + rfa = 0x01; /* Full-1.5K */ + break; + + case 8192: + rfd = 0x06; /* Full-4K */ + rfa = 0x0a; /* Full-6K */ + break; + + case 16384: + rfd = 0x06; /* Full-4K */ + rfa = 0x12; /* Full-10K */ + break; + + default: + rfd = 0x06; /* Full-4K */ + rfa = 0x1e; /* Full-16K */ + break; + } + + mtl_rx_op &= ~MTL_OP_MODE_RFD_MASK; + mtl_rx_op |= rfd << MTL_OP_MODE_RFD_SHIFT; + + mtl_rx_op &= ~MTL_OP_MODE_RFA_MASK; + mtl_rx_op |= rfa << MTL_OP_MODE_RFA_SHIFT; + } + writel(mtl_rx_op, ioaddr + MTL_CHAN_RX_OP_MODE(channel)); /* Enable MTL RX overflow */ @@ -262,7 +310,7 @@ static void dwmac4_dma_operation_mode(void __iomem *ioaddr, int txmode, int rxmode, int rxfifosz) { /* Only Channel 0 is actually configured and used */ - dwmac4_dma_chan_op_mode(ioaddr, txmode, rxmode, 0); + dwmac4_dma_chan_op_mode(ioaddr, txmode, rxmode, 0, rxfifosz); } static void dwmac4_get_hw_feature(void __iomem *ioaddr, -- 2.12.0