Manikanta Pubbisetty <quic_mpubbise@xxxxxxxxxxx> wrote:
> Commit 56c8ccf331bd ("ath11k: Add register access logic for WCN6750")
> regressed QCN9074. With the above mentioned commit, writes are failing
> for some registers on QCN9074 although the device seems to work
> normally.
>
> ath11k_pci 0000:03:00.0: failed to set pcie link register0x01e0e0a8: 0xffffffff != 0x00000010
> ath11k_pci 0000:03:00.0: failed to set sysclk: -110
>
> PCIe devices in ath11k (QCA6390, WCN6855, QCN9074, WCN6750) use window
> concept for register accesses. There are two schemes, dynamic & static
> window.
>
> In dynamic window scheme, a single window(region in the BAR) is mapped
> either to CE or DP register windows at any give time. QCA6390 & WCN6855
> follow this scheme for register accesses.
>
> In static window scheme, CE & DP register windows are statically mapped
> to separate regions with in the BAR so that there is no switching of
> register windows between CE & DP register accesses. QCN9074 & WCN6750
> follow this scheme although the window start offsets are different for
> QCN9074 & WCN6750.
>
> QCN9074 uses 3rd & 2nd window for DP & CE register accesses respectively
> whereas WCN6750 uses 1st & 2nd window for DP & CE. In QCN9074, along with
> 2nd & 3rd windows, 1st window is also used for certain configurations
> which commit 56c8ccf331bd ("ath11k: Add register access logic for WCN6750")
> did not account for and hence the regression.
>
> Fix this by going back to the original way of accessing the registers on
> QCN9074. Since this diverges from WCN6750 way of accessing registers, it
> is required to register window_read32/window_write32() pci_ops for WCN6750.
> We can also get rid of dp_window_idx & ce_window_idx members in hw_params,
> so remove them.
>
> Also add a new API ath11k_pcic_register_pci_ops() for registering pci_ops
> to the ath11k core. This API checks for mandatory pci_ops() and reports
> error if those are missing. Also initialize unused pci_ops to NULL.
>
> Tested-on: WCN6750 hw1.0 AHB WLAN.MSL.1.0.1-00887-QCAMSLSWPLZ-1
> Tested-on: QCN9074 hw1.0 PCI WLAN.HK.2.6.0.1-00861-QCAHKSWPL_SILICONZ-1
>
> Fixes: 56c8ccf331bd ("ath11k: Add register access logic for WCN6750")
> Reported-by: Maxime Bizon <mbizon@xxxxxxxxxx>
> Tested-by: Maxime Bizon <mbizon@xxxxxxxxxx>
> Signed-off-by: Manikanta Pubbisetty <quic_mpubbise@xxxxxxxxxxx>
> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx>
Patch applied to ath-next branch of ath.git, thanks.
867f4eeee862 wifi: ath11k: Fix register write failure on QCN9074
--
https://patchwork.kernel.org/project/linux-wireless/patch/20220608062954.27792-1-quic_mpubbise@xxxxxxxxxxx/
https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
