Re: [PATCH v2 1/1] net: axienet: Move reset before DMA detection

From: Maxim Kochetkov
Date: Thu Jun 22 2023 - 14:48:28 EST




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.