Re: [PATCH net-next v3 06/10] net: stmmac: xgmac: support per-channel irq

[Jisheng Zhang <jszhang@kernel.org>]

On Thu, Aug 10, 2023 at 04:52:01PM +0200, Alexandre TORGUE wrote:
> On 8/9/23 18:50, Jisheng Zhang wrote:
> > The IP supports per channel interrupt, add support for this usage case.
> > 
> > Signed-off-by: Jisheng Zhang <jszhang@kernel.org>
> > ---
> >   .../net/ethernet/stmicro/stmmac/dwxgmac2.h    |  2 ++
> >   .../ethernet/stmicro/stmmac/dwxgmac2_dma.c    | 33 +++++++++++--------
> >   2 files changed, 22 insertions(+), 13 deletions(-)
> > 
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
> > index 81cbb13a101d..12e1228ccf2a 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
> > +++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2.h
> > @@ -327,6 +327,8 @@
> >   /* DMA Registers */
> >   #define XGMAC_DMA_MODE			0x00003000
> > +#define XGMAC_INTM			GENMASK(13, 12)
> > +#define XGMAC_INTM_MODE1		0x1
> >   #define XGMAC_SWR			BIT(0)
> >   #define XGMAC_DMA_SYSBUS_MODE		0x00003004
> >   #define XGMAC_WR_OSR_LMT		GENMASK(29, 24)
> > diff --git a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
> > index b5ba4e0cca55..ef25af92d6cc 100644
> > --- a/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
> > +++ b/drivers/net/ethernet/stmicro/stmmac/dwxgmac2_dma.c
> > @@ -31,6 +31,13 @@ static void dwxgmac2_dma_init(void __iomem *ioaddr,
> >   		value |= XGMAC_EAME;
> >   	writel(value, ioaddr + XGMAC_DMA_SYSBUS_MODE);
> > +
> > +	if (dma_cfg->perch_irq_en) {
> > +		value = readl(ioaddr + XGMAC_DMA_MODE);
> > +		value &= ~XGMAC_INTM;
> > +		value |= FIELD_PREP(XGMAC_INTM, XGMAC_INTM_MODE1);
> > +		writel(value, ioaddr + XGMAC_DMA_MODE);
> > +	}
> >   }
> >   static void dwxgmac2_dma_init_chan(struct stmmac_priv *priv,
> > @@ -365,20 +372,20 @@ static int dwxgmac2_dma_interrupt(struct stmmac_priv *priv,
> >   	}
> >   	/* TX/RX NORMAL interrupts */
> > -	if (likely(intr_status & XGMAC_NIS)) {
> 
> No longer need to check NIS bit ?

Hi Alexandre,

NIS is RI | TI | TBU, since we have checked these three
bits we can ignore NIS. And dwmac4 behaves similarly.

Thanks

> 
> > -		if (likely(intr_status & XGMAC_RI)) {
> > -			u64_stats_update_begin(&rx_q->rxq_stats.syncp);
> > -			rx_q->rxq_stats.rx_normal_irq_n++;
> > -			u64_stats_update_end(&rx_q->rxq_stats.syncp);
> > -			ret |= handle_rx;
> > -		}
> > -		if (likely(intr_status & (XGMAC_TI | XGMAC_TBU))) {
> > -			u64_stats_update_begin(&tx_q->txq_stats.syncp);
> > -			tx_q->txq_stats.tx_normal_irq_n++;
> > -			u64_stats_update_end(&tx_q->txq_stats.syncp);
> > -			ret |= handle_tx;
> > -		}
> > +	if (likely(intr_status & XGMAC_RI)) {
> > +		u64_stats_update_begin(&rx_q->rxq_stats.syncp);
> > +		rx_q->rxq_stats.rx_normal_irq_n++;
> > +		u64_stats_update_end(&rx_q->rxq_stats.syncp);
> > +		ret |= handle_rx;
> > +	}
> > +	if (likely(intr_status & XGMAC_TI)) {
> > +		u64_stats_update_begin(&tx_q->txq_stats.syncp);
> > +		tx_q->txq_stats.tx_normal_irq_n++;
> > +		u64_stats_update_end(&tx_q->txq_stats.syncp);
> > +		ret |= handle_tx;
> >   	}
> > +	if (unlikely(intr_status & XGMAC_TBU))
> > +		ret |= handle_tx;
> >   	/* Clear interrupts */
> >   	writel(intr_en & intr_status, ioaddr + XGMAC_DMA_CH_STATUS(chan));
>