Re: [PATCH] wifi: ath11k: fix qmi memory allocation logic for CALDB region

[Baochen Qiang <baochen.qiang@oss.qualcomm.com>]

On 12/25/2025 5:47 AM, Alex G. wrote:
> On Monday, December 8, 2025 4:23:46 AM CST Baochen Qiang wrote:
>> On 12/7/2025 1:58 AM, Alexandru Gagniuc wrote:
>>> Memory region assignment in ath11k_qmi_assign_target_mem_chunk()
>>>
>>> assumes that:
>>>   1. firmware will make a HOST_DDR_REGION_TYPE request, and
>>>   2. this request is processed before CALDB_MEM_REGION_TYPE
>>>
>>> In this case CALDB_MEM_REGION_TYPE, can safely be assigned immediately
>>> after the host region.
>>>
>>> However, if the HOST_DDR_REGION_TYPE request is not made, or the
>>> reserved-memory node is not present, then res.start and res.end are 0,
>>> and host_ddr_sz remains uninitialized. The physical address should
>>> fall back to ATH11K_QMI_CALDB_ADDRESS. That doesn't happen:
>>>
>>> resource_size(&res) returns 1 for an empty resource, and thus the if
>>> clause never takes the fallback path. ab->qmi.target_mem[idx].paddr
>>> is assigned the uninitialized value of host_ddr_sz + 0 (res.start).
>>>
>>> Use "if (res.end > res.start)" for the predicate, which correctly
>>> falls back to ATH11K_QMI_CALDB_ADDRESS.
> 
> I am ready to submit the IPQ9574 support. This patch is a dependency. Should I 
> include this change in the series that adds IPQ9574?

Better not, first reason is for track purpose. And the second, since the patch is fixing a
broken commit, IMO being standalone makes it easy for stable team to do backport work.

> 
>> In addition, does it make sense to do of_reserved_mem_region_to_resource()
>> before the loop, which may give CALDB_MEM_REGION_TYPE a chance even
>> HOST_DDR_REGION_TYPE request is not made?
> 
> I'm sorry that I initially missed this question. I don't think we should move 
> &res initialization outside the loop. We also need host_ddr_sz to be 
> initialized by a HOST_DDR_REGION_TYPE (1) request. On IPQ9574, the firmware 
> doesn't make that request, so host_ddr_sz remains uninitialized. Since &res 
> and host_ddr_sz are used together, I think it's better to initialize them, 
> together.

fine then

> 
> 
> Without patch:
> 
>     ath11k c000000.wifi: qmi firmware request memory request
>     ath11k c000000.wifi: qmi mem seg type 4 size 409600
>     ath11k c000000.wifi: qmi mem seg type 2 size 262144
>     ath11k c000000.wifi: qmi mem seg type 3 size 1048576
>     ...
>     ath11k c000000.wifi: failed to assign qmi target memory: -5
> 
> 
> 
> With patch:
> 
>     ath11k c000000.wifi: qmi firmware request memory request
>     ath11k c000000.wifi: qmi mem seg type 4 size 409600
>     ath11k c000000.wifi: qmi mem seg type 2 size 262144
>     ath11k c000000.wifi: qmi mem seg type 3 size 1048576
>     ath11k c000000.wifi: qmi ignore invalid mem req type 3
>     ath11k c000000.wifi: qmi req mem_seg[0] 0x000000004ba00000 409600 4
>     ath11k c000000.wifi: qmi req mem_seg[1] 0x000000004b700000 262144 2
> 
> 
> Tested on : WLAN.HK.2.9.0.1-01890-QCAHKSWPL_SILICONZ-1
> 
> Alex
> 
> 
> 
>