From: Siddharth Vadapalli s-vadapalli@ti.com
commit 0ed577e7e8e508c24e22ba07713ecc4903e147c3 upstream.
In TI's AM62x/AM64x SoCs, successful teardown of RX DMA Channel raises an interrupt. The process of servicing this interrupt involves flushing all pending RX DMA descriptors and clearing the teardown completion marker (TDCM). The am65_cpsw_nuss_rx_packets() function invoked from the RX NAPI callback services the interrupt. Thus, it is necessary to wait for this handler to run, drain all packets and clear TDCM, before calling napi_disable() in am65_cpsw_nuss_common_stop() function post channel teardown. If napi_disable() executes before ensuring that TDCM is cleared, the TDCM remains set when the interfaces are down, resulting in an interrupt storm when the interfaces are brought up again.
Since the interrupt raised to indicate the RX DMA Channel teardown is specific to the AM62x and AM64x SoCs, add a quirk for it.
Fixes: 4f7cce272403 ("net: ethernet: ti: am65-cpsw: add support for am64x cpsw3g") Co-developed-by: Vignesh Raghavendra vigneshr@ti.com Signed-off-by: Vignesh Raghavendra vigneshr@ti.com Signed-off-by: Siddharth Vadapalli s-vadapalli@ti.com Reviewed-by: Roger Quadros rogerq@kernel.org Link: https://lore.kernel.org/r/20230209084432.189222-1-s-vadapalli@ti.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ethernet/ti/am65-cpsw-nuss.c | 12 +++++++++++- drivers/net/ethernet/ti/am65-cpsw-nuss.h | 1 + 2 files changed, 12 insertions(+), 1 deletion(-)
--- a/drivers/net/ethernet/ti/am65-cpsw-nuss.c +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.c @@ -500,7 +500,15 @@ static int am65_cpsw_nuss_common_stop(st k3_udma_glue_disable_tx_chn(common->tx_chns[i].tx_chn); }
+ reinit_completion(&common->tdown_complete); k3_udma_glue_tdown_rx_chn(common->rx_chns.rx_chn, true); + + if (common->pdata.quirks & AM64_CPSW_QUIRK_DMA_RX_TDOWN_IRQ) { + i = wait_for_completion_timeout(&common->tdown_complete, msecs_to_jiffies(1000)); + if (!i) + dev_err(common->dev, "rx teardown timeout\n"); + } + napi_disable(&common->napi_rx);
for (i = 0; i < AM65_CPSW_MAX_RX_FLOWS; i++) @@ -704,6 +712,8 @@ static int am65_cpsw_nuss_rx_packets(str
if (cppi5_desc_is_tdcm(desc_dma)) { dev_dbg(dev, "%s RX tdown flow: %u\n", __func__, flow_idx); + if (common->pdata.quirks & AM64_CPSW_QUIRK_DMA_RX_TDOWN_IRQ) + complete(&common->tdown_complete); return 0; }
@@ -2634,7 +2644,7 @@ static const struct am65_cpsw_pdata j721 };
static const struct am65_cpsw_pdata am64x_cpswxg_pdata = { - .quirks = 0, + .quirks = AM64_CPSW_QUIRK_DMA_RX_TDOWN_IRQ, .ale_dev_id = "am64-cpswxg", .fdqring_mode = K3_RINGACC_RING_MODE_RING, }; --- a/drivers/net/ethernet/ti/am65-cpsw-nuss.h +++ b/drivers/net/ethernet/ti/am65-cpsw-nuss.h @@ -86,6 +86,7 @@ struct am65_cpsw_rx_chn { };
#define AM65_CPSW_QUIRK_I2027_NO_TX_CSUM BIT(0) +#define AM64_CPSW_QUIRK_DMA_RX_TDOWN_IRQ BIT(1)
struct am65_cpsw_pdata { u32 quirks;