On 5/27/2025 12:26 PM, Amirreza Zarrabi wrote:
> Anyone with access to contiguous physical memory should be able to
> share memory with QTEE using shm_bridge.
>
> Tested-by: Neil Armstrong <neil.armstrong@xxxxxxxxxx>
> Signed-off-by: Amirreza Zarrabi <amirreza.zarrabi@xxxxxxxxxxxxxxxx>
> ---
> drivers/firmware/qcom/qcom_tzmem.c | 57 +++++++++++++++++++++++++-------
> include/linux/firmware/qcom/qcom_tzmem.h | 15 +++++++++
> 2 files changed, 60 insertions(+), 12 deletions(-)
>
> diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c
> index 4fe333fd2f07..e9e4f06924ae 100644
> --- a/drivers/firmware/qcom/qcom_tzmem.c
> +++ b/drivers/firmware/qcom/qcom_tzmem.c
> @@ -108,25 +108,61 @@ static int qcom_tzmem_init(void)
> return 0;
> }
>
> -static int qcom_tzmem_init_area(struct qcom_tzmem_area *area)
> +/**
> + * qcom_tzmem_shm_bridge_create() - Create a SHM bridge.
> + * @paddr: Physical address of the memory to share.
> + * @size: Size of the memory to share.
> + * @handle: Handle to the SHM bridge.
> + *
> + * On platforms that support SHM bridge, this function creates a SHM bridge
> + * for the given memory region with QTEE. The handle returned by this function
> + * must be passed to qcom_tzmem_shm_bridge_delete() to free the SHM bridge.
> + *
> + * Return: On success, returns 0; on failure, returns < 0.
> + */
> +int qcom_tzmem_shm_bridge_create(phys_addr_t paddr, size_t size, u64 *handle)
> {
> u64 pfn_and_ns_perm, ipfn_and_s_perm, size_and_flags;
> - int ret;
>
> if (!qcom_tzmem_using_shm_bridge)
> return 0;
>
> - pfn_and_ns_perm = (u64)area->paddr | QCOM_SCM_PERM_RW;
> - ipfn_and_s_perm = (u64)area->paddr | QCOM_SCM_PERM_RW;
> - size_and_flags = area->size | (1 << QCOM_SHM_BRIDGE_NUM_VM_SHIFT);
> + pfn_and_ns_perm = paddr | QCOM_SCM_PERM_RW;
> + ipfn_and_s_perm = paddr | QCOM_SCM_PERM_RW;
> + size_and_flags = size | (1 << QCOM_SHM_BRIDGE_NUM_VM_SHIFT);
> + if (qcom_scm_shm_bridge_create(pfn_and_ns_perm, ipfn_and_s_perm,
> + size_and_flags, QCOM_SCM_VMID_HLOS,
> + handle))
Can we add a debug log here to ease debugging in future?
Something like this can also work.
pr_err("Shm bridge creation failed, ret: %d, NS PA|Perm: 0x%llx,
size|flags: 0x%llx\n", ret, pfn_and_ns_perm_flags, size_and_flags);
> + return -EINVAL;
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(qcom_tzmem_shm_bridge_create);
--
Regards
Kuldeep
