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

[Alex G.]

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?

> 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.


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