The patch below does not apply to the 4.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 2e5644b1bab2ccea9cfc7a9520af95b94eb0dbf1 Mon Sep 17 00:00:00 2001 From: Robert Hancock robert.hancock@calian.com Date: Tue, 18 Jan 2022 15:41:24 -0600 Subject: [PATCH] net: axienet: increase reset timeout

The previous timeout of 1ms was too short to handle some cases where the core is reset just after the input clocks were started, which will be introduced in an upcoming patch. Increase the timeout to 50ms. Also simplify the reset timeout checking to use read_poll_timeout.

Fixes: 8a3b7a252dca9 ("drivers/net/ethernet/xilinx: added Xilinx AXI Ethernet driver") Signed-off-by: Robert Hancock robert.hancock@calian.com Reviewed-by: Andrew Lunn andrew@lunn.ch Signed-off-by: David S. Miller davem@davemloft.net

diff --git a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c index 23ac353b35fe..9c5b24af61fa 100644 --- a/drivers/net/ethernet/xilinx/xilinx_axienet_main.c +++ b/drivers/net/ethernet/xilinx/xilinx_axienet_main.c @@ -496,7 +496,8 @@ static void axienet_setoptions(struct net_device *ndev, u32 options)

static int __axienet_device_reset(struct axienet_local *lp) { - u32 timeout; + u32 value; + int ret;

/* Reset Axi DMA. This would reset Axi Ethernet core as well. The reset * process of Axi DMA takes a while to complete as all pending @@ -506,15 +507,13 @@ static int __axienet_device_reset(struct axienet_local *lp) * they both reset the entire DMA core, so only one needs to be used. */ axienet_dma_out32(lp, XAXIDMA_TX_CR_OFFSET, XAXIDMA_CR_RESET_MASK); - timeout = DELAY_OF_ONE_MILLISEC; - while (axienet_dma_in32(lp, XAXIDMA_TX_CR_OFFSET) & - XAXIDMA_CR_RESET_MASK) { - udelay(1); - if (--timeout == 0) { - netdev_err(lp->ndev, "%s: DMA reset timeout!\n", - __func__); - return -ETIMEDOUT; - } + ret = read_poll_timeout(axienet_dma_in32, value, + !(value & XAXIDMA_CR_RESET_MASK), + DELAY_OF_ONE_MILLISEC, 50000, false, lp, + XAXIDMA_TX_CR_OFFSET); + if (ret) { + dev_err(lp->dev, "%s: DMA reset timeout!\n", __func__); + return ret; }

return 0;