Re: [PATCH v3 stable-5.10] ath10k: Fix the MTU size on QCA9377 SDIO

[Greg KH <gregkh@linuxfoundation.org>]

On Mon, Jan 24, 2022 at 02:10:42PM -0300, Fabio Estevam wrote:
> [ Upstream commit 09b8cd69edcf2be04a781e1781e98e52a775c9ad ]
>     
> On an imx6dl-pico-pi board with a QCA9377 SDIO chip, simply trying to
> connect via ssh to another machine causes:
> 
> [   55.824159] ath10k_sdio mmc1:0001:1: failed to transmit packet, dropping: -12
> [   55.832169] ath10k_sdio mmc1:0001:1: failed to submit frame: -12
> [   55.838529] ath10k_sdio mmc1:0001:1: failed to push frame: -12
> [   55.905863] ath10k_sdio mmc1:0001:1: failed to transmit packet, dropping: -12
> [   55.913650] ath10k_sdio mmc1:0001:1: failed to submit frame: -12
> [   55.919887] ath10k_sdio mmc1:0001:1: failed to push frame: -12
> 
> , leading to an ssh connection failure.
> 
> One user inspected the size of frames on Wireshark and reported
> the followig:
> 
> "I was able to narrow the issue down to the mtu. If I set the mtu for
> the wlan0 device to 1486 instead of 1500, the issue does not happen.
> 
> The size of frames that I see on Wireshark is exactly 1500 after
> setting it to 1486."
> 
> Clearing the HI_ACS_FLAGS_ALT_DATA_CREDIT_SIZE avoids the problem and
> the ssh command works successfully after that.
> 
> Introduce a 'credit_size_workaround' field to ath10k_hw_params for
> the QCA9377 SDIO, so that the HI_ACS_FLAGS_ALT_DATA_CREDIT_SIZE
> is not set in this case.
> 
> Tested with QCA9377 SDIO with firmware WLAN.TF.1.1.1-00061-QCATFSWPZ-1.
> 
> Fixes: 2f918ea98606 ("ath10k: enable alt data of TX path for sdio")
> Signed-off-by: Fabio Estevam <festevam@denx.de>
> Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
> Link: https://lore.kernel.org/r/20211124131047.713756-1-festevam@denx.de
> ---
> Hi,
> 
> This is the resolution for the linux-stable 5.10 tree.
> 
> Changes since v2:
> - Add the missing blank line in hw.h like done in the upstream version.
> Changes since v1:
> - Added the missing change in hw.h.

Ok, trying this again...