From 831157756e3ce29f64019041eaeb5d4e8a131fbb Mon Sep 17 00:00:00 2001 From: Siddharth Vadapalli Date: Wed, 17 Apr 2024 15:24:25 +0530 Subject: [PATCH] net: ethernet: ti: am65-cpsw-nuss: cleanup DMA Channels before using them [ Upstream commit c24cd679b075b0e953ea167b0aa2b2d59e4eba7f ] The TX and RX DMA Channels used by the driver to exchange data with CPSW are not guaranteed to be in a clean state during driver initialization. The Bootloader could have used the same DMA Channels without cleaning them up in the event of failure. Thus, reset and disable the DMA Channels to ensure that they are in a clean state before using them. Fixes: 93a76530316a ("net: ethernet: ti: introduce am65x/j721e gigabit eth subsystem driver") Reported-by: Schuyler Patton Signed-off-by: Siddharth Vadapalli Reviewed-by: Roger Quadros Link: https://lore.kernel.org/r/20240417095425.2253876-1-s-vadapalli@ti.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/net/ethernet/ti/am65-cpsw-nuss.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) diff --git a/drivers/net/ethernet/ti/am65-cpsw-nuss.c b/drivers/net/ethernet/ti/am65-cpsw-nuss.c index f94d6d322df4..4bd57b79a023 100644 --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c @@ -2535,6 +2535,8 @@ static void am65_cpsw_unregister_devlink(struct am65_cpsw_common *common) static int am65_cpsw_nuss_register_ndevs(struct am65_cpsw_common *common) { + struct am65_cpsw_rx_chn *rx_chan = &common->rx_chns; + struct am65_cpsw_tx_chn *tx_chan = common->tx_chns; struct device *dev = common->dev; struct devlink_port *dl_port; struct am65_cpsw_port *port; @@ -2553,6 +2555,22 @@ static int am65_cpsw_nuss_register_ndevs(struct am65_cpsw_common *common) return ret; } + /* The DMA Channels are not guaranteed to be in a clean state. + * Reset and disable them to ensure that they are back to the + * clean state and ready to be used. + */ + for (i = 0; i < common->tx_ch_num; i++) { + k3_udma_glue_reset_tx_chn(tx_chan[i].tx_chn, &tx_chan[i], + am65_cpsw_nuss_tx_cleanup); + k3_udma_glue_disable_tx_chn(tx_chan[i].tx_chn); + } + + for (i = 0; i < AM65_CPSW_MAX_RX_FLOWS; i++) + k3_udma_glue_reset_rx_chn(rx_chan->rx_chn, i, rx_chan, + am65_cpsw_nuss_rx_cleanup, !!i); + + k3_udma_glue_disable_rx_chn(rx_chan->rx_chn); + ret = am65_cpsw_nuss_register_devlink(common); if (ret) return ret;