Subject: Re: [PATCH net-next v2 2/2] net: stmmac: Support enhanced addressing mode for DWMAC 4.10

From: Thierry Reding <[email-masked]>
Date: Mon, 9 Sep 2019 21:13:29 +0200

On Mon, Sep 09, 2019 at 04:05:52PM +0000, Jose Abreu wrote:
> From: Thierry Reding <[email-masked]>
> Date: Sep/09/2019, 16:25:46 (UTC+00:00)
> 
> > @@ -79,6 +79,10 @@ static void dwmac4_dma_init_rx_chan(void __iomem *ioaddr,
> >  	value = value | (rxpbl << DMA_BUS_MODE_RPBL_SHIFT);
> >  	writel(value, ioaddr + DMA_CHAN_RX_CONTROL(chan));
> >  
> > +	if (dma_cfg->eame)
> 
> There is no need for this check. If EAME is not enabled then upper 32 
> bits will be zero.

The idea here was to potentially guard against this register not being
available on some revisions. Having the check here would avoid access to
the register if the device doesn't support enhanced addressing.

> 
> > +		writel(upper_32_bits(dma_rx_phy),
> > +		       ioaddr + DMA_CHAN_RX_BASE_ADDR_HI(chan));
> > +
> >  	writel(lower_32_bits(dma_rx_phy), ioaddr + DMA_CHAN_RX_BASE_ADDR(chan));
> >  }
> 
> > @@ -97,6 +101,10 @@ static void dwmac4_dma_init_tx_chan(void __iomem *ioaddr,
> >  
> >  	writel(value, ioaddr + DMA_CHAN_TX_CONTROL(chan));
> >  
> > +	if (dma_cfg->eame)
> 
> Same here.
> 
> > +		writel(upper_32_bits(dma_tx_phy),
> > +		       ioaddr + DMA_CHAN_TX_BASE_ADDR_HI(chan));
> > +
> >  	writel(lower_32_bits(dma_tx_phy), ioaddr + DMA_CHAN_TX_BASE_ADDR(chan));
> >  }
> 
> Also, please provide a cover letter in next submission.

Alright, will do.

Thierry