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Date:   Thu, 22 Jun 2023 21:48:19 +0300
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Subject: Re: [PATCH v2 1/1] net: axienet: Move reset before DMA detection
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To:     "Pandey, Radhey Shyam" <radhey.shyam.pandey@amd.com>,
        "netdev@vger.kernel.org" <netdev@vger.kernel.org>
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        "Simek, Michal" <michal.simek@amd.com>,
        Andrew Lunn <andrew@lunn.ch>,
        Robert Hancock <robert.hancock@calian.com>,
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On 22.06.2023 21:43, Pandey, Radhey Shyam wrote:

>> DMA detection will fail if axinet was started before (by boot loader,
> 
> :%s/axinet/axienet/g
Sorry about that. I will fix it in v3.

> 
>> boot ROM, etc). In this state axinet will not start properly.
>> XAXIDMA_TX_CDESC_OFFSET + 4 register (MM2S_CURDESC_MSB) is used to
>> detect
>> 64 DMA capability here. But datasheet says: When DMACR.RS is 1
>> (axinet is in enabled state), CURDESC_PTR becomes Read Only (RO) and
>> is used to fetch the first descriptor. So iowrite32()/ioread32() trick
>> to this register to detect DMA will not work.
>> So move axinet reset before DMA detection.
>>
>> Fixes: 04cc2da39698 ("net: axienet: reset core on initialization prior to MDIO
> 
> Is this fixes tag correct ? I think the failure is introduced after
> f735c40ed93c net: axienet: Autodetect 64-bit DMA capability?

Yes of course. I will fix it in v3.