ACK: [PATCH 0/2][SRU][K/J/OEM-6.0] Fix iosm: WWAN cannot build the connection (DW5823e)

[Tim Gardner]

On 11/28/22 7:41 AM, Koba Ko wrote:
> BugLink: https://bugs.launchpad.net/bugs/1998115
> 
> [Impact]
>   WWAN(DW5823e) can't build the connection successfully.
> 
> [Fix]
>   With INTEL_IOMMU disable config or by forcing intel_iommu=off from
>   grub some of the features of IOSM driver like browsing, flashing &
>   coredump collection is not working.
> 
>   When driver calls DMA API - dma_map_single() for tx transfers. It is
>   resulting in dma mapping error.
> 
>   Set the device DMA addressing capabilities using dma_set_mask() and
>   remove the INTEL_IOMMU dependency in kconfig so that driver follows
>   the platform config either INTEL_IOMMU enable or disable.
> 
>   Because the generic jammy(5.15) doesn't contain NET_DEVLINK and RELAY
>   CONFIGs yet on iosm module, the single patch is necessary for Jammy.
> 
> [Test Case]
>   1. boot up with kernel applied the FIX.
>   2. check the status of wwan by "mmcli -m 0"
>       Status| unlock retries: sim-pin (3)
>             | state: ^[32mconnected^[0m
>             | power state: on
>             | access tech: lte
>             | signal quality: 45% (recent)
>        ----------------------------------
>        3GPP | imei: ######
>             | enabled locks: sim, fixed-dialing
>             | operator id: 46692
>             | operator name: Chunghwa Telecom
>             | registration: home
>             | packet service state: attached
>             | pco:
>             | 0: (complete)
> 
> [Where problems could occur]
> remove the dependency for intel_iommu, iosm would fit better on other platforms not only Intel.
> 
> M Chetan Kumar (1):
>    net: wwan: iosm: fix driver not working with INTEL_IOMMU disabled
> 
>   drivers/net/wwan/Kconfig              | 2 +-
>   drivers/net/wwan/iosm/iosm_ipc_pcie.c | 7 +++++++
>   2 files changed, 8 insertions(+), 1 deletion(-)
> 
Acked-by: Tim Gardner <tim.gardner at canonical.com>
-- 
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Tim Gardner
Canonical, Inc