Re: [PATCH v2] net: stmmac: Fix interrupt handling for level-triggered mode in DWC_XGMAC2

[Yanteng Si <si.yanteng@linux.dev>]

在 7/3/25 10:04 AM, EricChan 写道:
> According to the Synopsys Controller IP XGMAC-10G Ethernet MAC Databook
> v3.30a (section 2.7.2), when the INTM bit in the DMA_Mode register is set
> to 2, the sbd_perch_tx_intr_o[] and sbd_perch_rx_intr_o[] signals operate
> in level-triggered mode. However, in this configuration, the DMA does not
> assert the XGMAC_NIS status bit for Rx or Tx interrupt events.
> 
> This creates a functional regression where the condition
> if (likely(intr_status & XGMAC_NIS)) in dwxgmac2_dma_interrupt() will
> never evaluate to true, preventing proper interrupt handling for
> level-triggered mode. The hardware specification explicitly states that
> "The DMA does not assert the NIS status bit for the Rx or Tx interrupt
> events" (Synopsys DWC_XGMAC2 Databook v3.30a, sec. 2.7.2).
> 

> The fix ensures correct handling of both edge and level-triggered
> interrupts while maintaining backward compatibility with existing
> configurations. It has been tested on the hardware device (not publicly
> available), and it can properly trigger the RX and TX interrupt handling
> in both the INTM=0 and INTM=2 configurations.
Is there anyone willing to help test this patch on a publicly
available DWC_XGMAC2 hardware device (if such a public device exists)?


Thanks,
Yanteng