RE: [PATCH 0/2] net: wwan: qcom_bam_dmux: Alloc RX buffers as a single coherent block

[Jagielski, Jedrzej]

From: Vishnu Santhosh <vishnu.santhosh@xxxxxxxxxxxxxxxx> 
Sent: Tuesday, July 14, 2026 7:33 AM

>On platforms where the modem DMAs into the BAM-DMUX RX data buffers and
>the XPU (eXternal Protection Unit) enforces per-region access control,
>each individually DMA-mapped RX buffer consumes an XPU resource group.
>With only ~16 groups available on Shikra (mDSP, VMID 43 / NAV), the
>per-buffer mappings exhaust the table and inbound transfers fault.
>
>This series adds a qcom,shikra-bam-dmux compatible and have the driver
>select QCOM_SCM_VMID_NAV internally via that compatible's match data.
>When matched, the driver allocates all RX buffers as a single
>contiguous coherent block and SCM-assigns it to HLOS plus the VMID
>once at probe, consuming one XPU resource group instead of many.
>
>Platforms that do not use the qcom,shikra-bam-dmux compatible are
>unaffected: the existing per-buffer dma_map_single() path is
>unchanged.
>
>Signed-off-by: Vishnu Santhosh <vishnu.santhosh@xxxxxxxxxxxxxxxx>
>---
>Vishnu Santhosh (2):
>      dt-bindings: net: qcom,bam-dmux: Add qcom,shikra-bam-dmux compatible
>      net: wwan: qcom_bam_dmux: Alloc RX buffers as a single coherent block
>
> .../devicetree/bindings/net/qcom,bam-dmux.yaml     |   8 +-
> drivers/net/wwan/Kconfig                           |   1 +
> drivers/net/wwan/qcom_bam_dmux.c                   | 134 +++++++++++++++++++--
> 3 files changed, 132 insertions(+), 11 deletions(-)
>---
>base-commit: 3b029c035b34bbc693405ddf759f0e9b920c27f1
>change-id: 20260714-qcom-bam-dmux-vmid-ext-d9289db310c1
>
>Best regards,
>-- 
>Vishnu Santhosh <vishnu.santhosh@xxxxxxxxxxxxxxxx>

Hi Vishnu
you need to specify target tree, net-next for this series i believe
please refer to[1]

[1]
https://docs.kernel.org/process/maintainer-netdev.html#indicating-target-tree