Re: [PATCH v5 1/3] remoteproc: qcom: pas: add needs_tzmem flag to trigger shmbridge creation

[Mukesh Ojha]

On Tue, Jul 07, 2026 at 03:12:44AM -0700, Ananthu C V wrote:
> SHM bridge creation is required to enable memory protection for both
> remoteproc metadata and its memory region on Qualcomm SoCs running
> non-Gunyah based Hypervisors. We currently rely on the iommu property
> being present in the remoteproc nodes to detect this.
> 
> However, this doesn't cover for cases where the remoteproc does a late
> attach, like SoCCP, and for remoteprocs like OOBM SS (Out of Band
> Management Sub-system) that doesn't have an iommu in front of it. In the
> former case, any attempt to create new mappings would fail with EEXIST
> as they are already setup by the bootloader when the SoCCP is brought
> out of reset, and unmapping them to create fresh mappings leads to faults
> since SoCCP could have active transactions on the bus. In the latter case,
> absence of iommu will be caught by the has_iommu flag, and SHM bridge
> creation will be skipped.
> 
> Fix this by introducing a needs_tzmem flag which would cover for the
> above edge cases by serving as an alternate trigger to the PAS helpers
> to ensure that SHM bridge is established.
> 
> Signed-off-by: Ananthu C V <ananthu.cv@xxxxxxxxxxxxxxxx>
> ---
>  drivers/remoteproc/qcom_q6v5_pas.c | 24 ++++++++++++++++++++++--
>  1 file changed, 22 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/remoteproc/qcom_q6v5_pas.c b/drivers/remoteproc/qcom_q6v5_pas.c
> index 60a4337d9e51..cd7273fbcf98 100644
> --- a/drivers/remoteproc/qcom_q6v5_pas.c
> +++ b/drivers/remoteproc/qcom_q6v5_pas.c
> @@ -61,6 +61,7 @@ struct qcom_pas_data {
>  	bool region_assign_shared;
>  	int region_assign_vmid;
>  	bool early_boot;
> +	bool needs_tzmem;
>  };
>  
>  struct qcom_pas {
> @@ -914,8 +915,8 @@ static int qcom_pas_probe(struct platform_device *pdev)
>  		goto remove_ssr_sysmon;
>  	}
>  
> -	pas->pas_ctx->use_tzmem = rproc->has_iommu;
> -	pas->dtb_pas_ctx->use_tzmem = rproc->has_iommu;
> +	pas->pas_ctx->use_tzmem = desc->needs_tzmem || rproc->has_iommu;
> +	pas->dtb_pas_ctx->use_tzmem = desc->needs_tzmem || rproc->has_iommu;
>  
>  	if (desc->early_boot)
>  		pas->rproc->state = RPROC_DETACHED;
> @@ -1657,8 +1658,27 @@ static const struct qcom_pas_data kaanapali_soccp_resource = {
>  	.early_boot = true,
>  };
>  
> +static const struct qcom_pas_data glymur_soccp_resource = {
> +	.crash_reason_smem = 656,
> +	.firmware_name = "soccp.mbn",
> +	.dtb_firmware_name = "soccp_dtb.mbn",
> +	.pas_id = 51,
> +	.dtb_pas_id = 0x41,
> +	.proxy_pd_names = (char*[]){
> +		"cx",
> +		"mx",
> +		NULL
> +	},
> +	.ssr_name = "soccp",
> +	.sysmon_name = "soccp",
> +	.auto_boot = true,
> +	.early_boot = true,
> +	.needs_tzmem = true,
> +};
> +
>  static const struct of_device_id qcom_pas_of_match[] = {
>  	{ .compatible = "qcom,eliza-adsp-pas", .data = &sm8550_adsp_resource },
> +	{ .compatible = "qcom,glymur-soccp-pas", .data = &glymur_soccp_resource },
>  	{ .compatible = "qcom,kaanapali-soccp-pas", .data = &kaanapali_soccp_resource },
>  	{ .compatible = "qcom,milos-adsp-pas", .data = &sm8550_adsp_resource },
>  	{ .compatible = "qcom,milos-cdsp-pas", .data = &milos_cdsp_resource },
> 


Reviewed-by: Mukesh Ojha <mukesh.ojha@xxxxxxxxxxxxxxxx>

> -- 
> 2.43.0
> 

-- 
-Mukesh Ojha