From mboxrd@z Thu Jan  1 00:00:00 1970
From: Nicolas Ferre <nicolas.ferre@microchip.com>
Subject: Re: [PATCH v2] net: macb: Clean 64b dma addresses if they are not
 detected
Date: Tue, 25 Sep 2018 09:00:35 +0200
Message-ID: <910b3083-fc17-9d6c-b2d1-69d41d3def5b@microchip.com>
References: <68051905ba59d7cfd74c63ef5bf0830dc2b9f6fe.1537857166.git.michal.simek@xilinx.com>
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Cc: "David S. Miller" <davem@davemloft.net>, <netdev@vger.kernel.org>,
        Claudiu Beznea - M18063 <Claudiu.Beznea@microchip.com>
To: Michal Simek <michal.simek@xilinx.com>,
        <linux-kernel@vger.kernel.org>, <monstr@monstr.eu>,
        "Edgar E. Iglesias" <edgar.iglesias@xilinx.com>
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On 25/09/2018 at 08:32, Michal Simek wrote:
> Clear ADDR64 dma bit in DMACFG register in case that HW_DMA_CAP_64B is
> not detected on 64bit system.
> The issue was observed when bootloader(u-boot) does not check macb
> feature at DCFG6 register (DAW64_OFFSET) and enabling 64bit dma support
> by default. Then macb driver is reading DMACFG register back and only
> adding 64bit dma configuration but not cleaning it out.
> 
> Signed-off-by: Michal Simek <michal.simek@xilinx.com>

Acked-by: Nicolas Ferre <nicolas.ferre@microchip.com>

Thanks Michal. Best regards,
   Nicolas

> ---
> 
> Changes in v2:
> - Clean reg at the first place - Edgar
> - Update commit message
> 
>   drivers/net/ethernet/cadence/macb_main.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
> index 16e4ef7d7185..ed8a5c53467e 100644
> --- a/drivers/net/ethernet/cadence/macb_main.c
> +++ b/drivers/net/ethernet/cadence/macb_main.c
> @@ -2160,6 +2160,7 @@ static void macb_configure_dma(struct macb *bp)
>   		else
>   			dmacfg &= ~GEM_BIT(TXCOEN);
>   
> +		dmacfg &= ~GEM_BIT(ADDR64);
>   #ifdef CONFIG_ARCH_DMA_ADDR_T_64BIT
>   		if (bp->hw_dma_cap & HW_DMA_CAP_64B)
>   			dmacfg |= GEM_BIT(ADDR64);
> 


-- 
Nicolas Ferre