Re: [PATCH] arm64: dts: qcom: kodiak: avoid EFI overlap for ADSP remote heap

[Ekansh Gupta]

On 23-04-2026 14:20, Konrad Dybcio wrote:
> On 4/23/26 8:35 AM, Jianping Li wrote:
>> On KODIAK platforms boot can fail when the DT "adsp-rpc-remote-heap"
>> reserved-memory region overlaps with firmware allocations (UEFI/EFI
>> runtime). The kernel then reports failure to reserve the region and
>> subsequent EFI runtime activity may trigger aborts.
>>
>> The remote heap node was described as a fixed "no-map" region, which
>> turns it into a hard carveout. Replace it with a "shared-dma-pool"
>> reserved memory region with reusable CMA-backed allocation, specifying
>> alignment and size.
>>
>> This avoids hard carveouts and reduces the chance of conflicting with
>> firmware memory maps while keeping an explicit pool for ADSP remote
>> heap usage.
>>
>> Fixes: 90a58ffa9c55 ("arm64: dts: qcom: kodiak: Add memory region for audiopd")
>> Cc: stable@xxxxxxxxxx
>> Signed-off-by: Jianping Li <jianping.li@xxxxxxxxxxxxxxxx>
>> ---
>>  arch/arm64/boot/dts/qcom/kodiak.dtsi | 9 ++++++---
>>  1 file changed, 6 insertions(+), 3 deletions(-)
>>
>> diff --git a/arch/arm64/boot/dts/qcom/kodiak.dtsi b/arch/arm64/boot/dts/qcom/kodiak.dtsi
>> index 988ca5f7c8a0..420219823496 100644
>> --- a/arch/arm64/boot/dts/qcom/kodiak.dtsi
>> +++ b/arch/arm64/boot/dts/qcom/kodiak.dtsi
>> @@ -191,9 +191,12 @@ rmtfs_mem: rmtfs@9c900000 {
>>  			qcom,vmid = <QCOM_SCM_VMID_MSS_MSA>;
>>  		};
>>  
>> -		adsp_rpc_remote_heap_mem: adsp-rpc-remote-heap@9cb80000 {
>> -			reg = <0x0 0x9cb80000 0x0 0x800000>;
>> -			no-map;
>> +		adsp_rpc_remote_heap_mem: adsp-rpc-remote-heap {
>> +			compatible = "shared-dma-pool";
>> +			alloc-ranges = <0x0 0x00000000 0x0 0xffffffff>;
> 
> Since DRAM starts at 0x8000_0000, is it intended to only allow this
> region to be in the lower 2 gigs?
> 
> (it may very well be for some historical reasons)
yes, this is intentional. ADSP supports 32-bit address.
> 
> Konrad
>