hacked 4.4.6+, 10.4.3 firmware, Running out of ring-index for pipe-id 3 (WMI).

[Michal Kazior]

On 28 March 2016 at 21:01, Ben Greear <greearb at candelatech.com> wrote:
> I'm seeing the ring-full messages below when running 35 stations on
> modified 10.4.3 firmware.  I also have serial console logging enabled, so
> things are running a bit slow...this seems to exacerbate the issue.
>
> [   91.108923] ath10k_pci 0000:05:00.0: htc failed hif-tx-sq: -105 eid: 2
> credits: 1 ep->tx_credits: 1  credit-flow-enabled: 1
> [   91.108932] ath10k_pci 0000:05:00.0: could not request stats (type 128
> ret -105)
> [   91.108942] ath10k_pci 0000:05:00.0: hif-tx-sg, full, nentries_mask: 0x1f
> write_idx: 2 sw-idx: 3  n_items: 1 pipe-id: 3
> [   91.108944] ath10k_pci 0000:05:00.0: htc failed hif-tx-sq: -105 eid: 2
> credits: 1 ep->tx_credits: 1  credit-flow-enabled: 1
> [   91.108952] ath10k_pci 0000:05:00.0: could not request stats (type 1 ret
> -105)
> [   91.108953] ath10k_pci 0000:05:00.0: failed to get fw stats for ethtool:
> -105
> [   91.109039] ath10k_pci 0000:05:00.0: hif-tx-sg, full, nentries_mask: 0x1f
> write_idx: 2 sw-idx: 3  n_items: 1 pipe-id: 3
> [   91.109041] ath10k_pci 0000:05:00.0: htc failed hif-tx-sq: -105 eid: 2
> credits: 1 ep->tx_credits: 1  credit-flow-enabled: 1
> [   91.109050] ath10k_pci 0000:05:00.0: could not request stats (type 128
> ret -105)
> [   91.109060] ath10k_pci 0000:05:00.0: hif-tx-sg, full, nentries_mask: 0x1f
> write_idx: 2 sw-idx: 3  n_items: 1 pipe-id: 3
> [   91.109062] ath10k_pci 0000:05:00.0: htc failed hif-tx-sq: -105 eid: 2
> credits: 1 ep->tx_credits: 1  credit-flow-enabled: 1
> [   91.109070] ath10k_pci 0000:05:00.0: could not request stats (type 1 ret
> -105)
> [   91.109072] ath10k_pci 0000:05:00.0: failed to get fw stats for ethtool:
> -105
> [   91.109157] ath10k_pci 0000:05:00.0: hif-tx-sg, full, nentries_mask: 0x1f
> write_idx: 2 sw-idx: 3  n_items: 1 pipe-id: 3
> [   91.109160] ath10k_pci 0000:05:00.0: htc failed hif-tx-sq: -105 eid: 2
> credits: 1 ep->tx_credits: 1  credit-flow-enabled: 1
>
>
> I am struggling to understand how the pipe can be full since we have
> tx-credits logic
> enabled for the WMI pipe.
>
> Any suggestions on what sort of bugs could cause this?
>
> And, should the ath10k_wmi_cmd_send retry when we get a -105 return
> code in hopes it will free up shortly instead of just failing and leaving
> the system in invalid state?

It probably shouldn't. As you've pointed out HTC tx credits should
prevent this in the first place. If you see -105 it means something is
really broken and needs to be fixed properly.

A thing that comes to mind is that CE -for whatever reason- would need
to stop completing CE ring items. Are you running with MSI? 1 or
multiple interrupts? Did you try forcing legacy interrupt mode to rule
out MSI problems?

You could add a debug messages to see if the HTC-WMI CE ring gets tx
completions properly.



Michał