[PATCH v7 09/11] optee: support protected memory allocation

[Jens Wiklander <jens.wiklander@linaro.org>]

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.wiklander@linaro.org>
---
 drivers/tee/optee/core.c    |  1 +
 drivers/tee/optee/smc_abi.c | 44 +++++++++++++++++++++++++++++++++++--
 2 files changed, 43 insertions(+), 2 deletions(-)

diff --git a/drivers/tee/optee/core.c b/drivers/tee/optee/core.c
index c75fddc83576..c7fd8040480e 100644
--- a/drivers/tee/optee/core.c
+++ b/drivers/tee/optee/core.c
@@ -181,6 +181,7 @@ 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/smc_abi.c b/drivers/tee/optee/smc_abi.c
index cfdae266548b..c10b38b23586 100644
--- a/drivers/tee/optee/smc_abi.c
+++ b/drivers/tee/optee/smc_abi.c
@@ -1620,6 +1620,41 @@ static inline int optee_load_fw(struct platform_device *pdev,
 }
 #endif
 
+static int optee_rstmem_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;
+		}
+
+		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;
@@ -1715,7 +1750,7 @@ 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;
@@ -1788,6 +1823,10 @@ static int optee_probe(struct platform_device *pdev)
 		pr_info("Asynchronous notifications enabled\n");
 	}
 
+	rc = optee_rstmem_pool_init(optee);
+	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
@@ -1823,6 +1862,7 @@ 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:
@@ -1839,7 +1879,7 @@ 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