On Tue, May 20, 2025 at 05:16:50PM +0200, Jens Wiklander wrote:
> Add support in the OP-TEE backend driver for protected memory
> allocation. The support is limited to only the SMC ABI and for secure
> video buffers.
>
> OP-TEE is probed for the range of protected physical memory and a
> memory pool allocator is initialized if OP-TEE have support for such
> memory.
>
> Signed-off-by: Jens Wiklander <jens.wiklan...@linaro.org>
> ---
> drivers/tee/optee/core.c | 10 +++++++
> drivers/tee/optee/optee_private.h | 2 ++
> drivers/tee/optee/smc_abi.c | 45 +++++++++++++++++++++++++++++--
> 3 files changed, 55 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
> index c75fddc83576..4b14a7ac56f9 100644
> --- a/drivers/tee/optee/core.c
> +++ b/drivers/tee/optee/core.c
> @@ -56,6 +56,15 @@ int optee_rpmb_intf_rdev(struct notifier_block *intf,
> unsigned long action,
> return 0;
> }
>
> +int optee_set_dma_mask(struct optee *optee, u_int pa_width)
> +{
> + u64 mask = DMA_BIT_MASK(min(64, pa_width));
> +
> + optee->teedev->dev.dma_mask = &optee->teedev->dev.coherent_dma_mask;
> +
> + return dma_set_mask_and_coherent(&optee->teedev->dev, mask);
> +}
> +
> static void optee_bus_scan(struct work_struct *work)
> {
> WARN_ON(optee_enumerate_devices(PTA_CMD_GET_DEVICES_SUPP));
> @@ -181,6 +190,7 @@ void optee_remove_common(struct optee *optee)
> tee_device_unregister(optee->supp_teedev);
> tee_device_unregister(optee->teedev);
>
> + tee_device_unregister_all_dma_heaps(optee->teedev);
> tee_shm_pool_free(optee->pool);
> optee_supp_uninit(&optee->supp);
> mutex_destroy(&optee->call_queue.mutex);
> diff --git a/drivers/tee/optee/optee_private.h
> b/drivers/tee/optee/optee_private.h
> index dc0f355ef72a..5e3c34802121 100644
> --- a/drivers/tee/optee/optee_private.h
> +++ b/drivers/tee/optee/optee_private.h
> @@ -272,6 +272,8 @@ struct optee_call_ctx {
>
> extern struct blocking_notifier_head optee_rpmb_intf_added;
>
> +int optee_set_dma_mask(struct optee *optee, u_int pa_width);
> +
> int optee_notif_init(struct optee *optee, u_int max_key);
> void optee_notif_uninit(struct optee *optee);
> int optee_notif_wait(struct optee *optee, u_int key, u32 timeout);
> diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c
> index f0c3ac1103bb..f3cae8243785 100644
> --- a/drivers/tee/optee/smc_abi.c
> +++ b/drivers/tee/optee/smc_abi.c
> @@ -1584,6 +1584,42 @@ static inline int optee_load_fw(struct platform_device
> *pdev,
> }
> #endif
>
> +static int optee_protmem_pool_init(struct optee *optee)
> +{
> + enum tee_dma_heap_id heap_id = TEE_DMA_HEAP_SECURE_VIDEO_PLAY;
> + struct tee_protmem_pool *pool;
> + int rc;
> +
> + if (optee->smc.sec_caps & OPTEE_SMC_SEC_CAP_PROTMEM) {
> + union {
> + struct arm_smccc_res smccc;
> + struct optee_smc_get_protmem_config_result result;
> + } res;
> +
> + optee->smc.invoke_fn(OPTEE_SMC_GET_PROTMEM_CONFIG, 0, 0, 0, 0,
> + 0, 0, 0, &res.smccc);
> + if (res.result.status != OPTEE_SMC_RETURN_OK) {
> + pr_err("Secure Data Path service not available\n");
> + return 0;
> + }
> + rc = optee_set_dma_mask(optee, res.result.pa_width);
> + if (!rc)
> + pool = tee_protmem_static_pool_alloc(res.result.start,
> + res.result.size);
> + if (IS_ERR(pool))
> + return PTR_ERR(pool);
> +
> + rc = tee_device_register_dma_heap(optee->teedev, heap_id, pool);
> + if (rc)
> + goto err;
> + }
> +
> + return 0;
> +err:
> + pool->ops->destroy_pool(pool);
> + return rc;
> +}
> +
> static int optee_probe(struct platform_device *pdev)
> {
> optee_invoke_fn *invoke_fn;
> @@ -1679,7 +1715,7 @@ static int optee_probe(struct platform_device *pdev)
> optee = kzalloc(sizeof(*optee), GFP_KERNEL);
> if (!optee) {
> rc = -ENOMEM;
> - goto err_free_pool;
> + goto err_free_shm_pool;
> }
>
> optee->ops = &optee_ops;
> @@ -1752,6 +1788,10 @@ static int optee_probe(struct platform_device *pdev)
> pr_info("Asynchronous notifications enabled\n");
> }
>
> + rc = optee_protmem_pool_init(optee);
Here we should do a Kconfig check for CONFIG_DMABUF_HEAPS so that we
don't proceed any further with initialization.
Rest looks good to me.
-Sumit
> + if (rc)
> + goto err_notif_uninit;
> +
> /*
> * Ensure that there are no pre-existing shm objects before enabling
> * the shm cache so that there's no chance of receiving an invalid
> @@ -1787,6 +1827,7 @@ static int optee_probe(struct platform_device *pdev)
> optee_disable_shm_cache(optee);
> optee_smc_notif_uninit_irq(optee);
> optee_unregister_devices();
> + tee_device_unregister_all_dma_heaps(optee->teedev);
> err_notif_uninit:
> optee_notif_uninit(optee);
> err_close_ctx:
> @@ -1803,7 +1844,7 @@ static int optee_probe(struct platform_device *pdev)
> tee_device_unregister(optee->teedev);
> err_free_optee:
> kfree(optee);
> -err_free_pool:
> +err_free_shm_pool:
> tee_shm_pool_free(pool);
> if (memremaped_shm)
> memunmap(memremaped_shm);
> --
> 2.43.0
>
