[FS#770] DMA fails to stop

[LEDE Bugs]

The following task has a new comment added:

FS#770 - DMA fails to stop
User who did this - aversario (aversario)

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And a few more lines:

[507784.092191] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000084c0
[523337.438108] ath: phy0: Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x40d22
[523337.459262] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000042c0
[733631.673762] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000084c0
[765308.298776] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000084c0
[803643.526952] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000084c0
[1158658.496570] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000042c0
[1420577.212619] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000084c0
[1423673.902872] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000084c0
[1426882.994714] ath: phy0: Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x40d22
[1426883.030189] ath: phy0: DMA failed to stop in 10 ms AR_CR=0x00000024 AR_DIAG_SW=0x42100020 DMADBG_7=0x000084c0
[1457611.807215] ath: phy0: Timeout while waiting for nf to load: AR_PHY_AGC_CONTROL=0x40d22
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More information can be found at the following URL:
https://bugs.lede-project.org/index.php?do=details&task_id=770#comment3025