core: OCALL support (OP-TEE Core part)

Adds the ability for Core to perform "Out Calls", or OCALLs. OCALLs allow OP-TEE Core PTA services to invoke commands on their corresponding client in the same way that client can invoke commands on TAs. Adds a new capability that reports whether OP-TEE was built with OCALL support. Signed-off-by: Hernan Gatta <hegatta@microsoft.com> Reviewed-by: Jerome Forissier <jerome@forissier.org> [etienne: picked from OP-TEE#3673 series] [etienne: split CFG_OCALL into CFG_{CORE|USER}_OCALL, no libutee, no pta] Signed-off-by: Etienne Carriere <etienne.carriere@linaro.org> Change-Id: I410d8f5743473177f7091c6db0f9aea5fe4ce5bc Reviewed-on: https://gerrit.st.com/c/mpu/oe/optee/optee_os/+/202483 Tested-by: Etienne CARRIERE <etienne.carriere@foss.st.com> Tested-by: Lionel DEBIEVE <lionel.debieve@foss.st.com> Reviewed-by: Etienne CARRIERE <etienne.carriere@foss.st.com> Reviewed-by: Lionel DEBIEVE <lionel.debieve@foss.st.com>
STMicroelectronics · May 23, 2022 · 5b86d56 · 5b86d56
1 parent 2a17bf7
commit 5b86d56
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Showing 5 changed files with 26 additions and 2 deletions.
diff --git a/core/arch/arm/include/kernel/thread.h b/core/arch/arm/include/kernel/thread.h
@@ -2,7 +2,7 @@
 /*
  * Copyright (c) 2014, STMicroelectronics International N.V.
  * Copyright (c) 2016-2017, Linaro Limited
- * Copyright (c) 2020-2021, Arm Limited
+ * Copyright (c) 2020, Arm Limited
  */
 
 #ifndef KERNEL_THREAD_H
@@ -20,7 +20,7 @@
 #define THREAD_ID_0		0
 #define THREAD_ID_INVALID	-1
 
-#define THREAD_RPC_MAX_NUM_PARAMS	U(4)
+#define THREAD_RPC_MAX_NUM_PARAMS	U(6)
 
 #ifndef __ASSEMBLER__
 

diff --git a/core/arch/arm/include/sm/optee_smc.h b/core/arch/arm/include/sm/optee_smc.h
@@ -291,6 +291,8 @@
 #define OPTEE_SMC_SEC_CAP_MEMREF_NULL		BIT(4)
 /* Secure world supports asynchronous notification of normal world */
 #define OPTEE_SMC_SEC_CAP_ASYNC_NOTIF		BIT(5)
+/* Secure world is built with OCALL support */
+#define OPTEE_SMC_SEC_CAP_OCALL			BIT(31)
 
 #define OPTEE_SMC_FUNCID_EXCHANGE_CAPABILITIES	U(9)
 #define OPTEE_SMC_EXCHANGE_CAPABILITIES \

diff --git a/core/arch/arm/tee/entry_fast.c b/core/arch/arm/tee/entry_fast.c
@@ -100,6 +100,9 @@ static void tee_entry_exchange_capabilities(struct thread_smc_args *args)
 	DMSG("Asynchronous notifications are %sabled",
 	     IS_ENABLED(CFG_CORE_ASYNC_NOTIF) ? "en" : "dis");
 
+	if (IS_ENABLED(CFG_CORE_OCALL))
+		args->a1 |= OPTEE_SMC_SEC_CAP_OCALL;
+
 #if defined(CFG_CORE_DYN_SHM)
 	dyn_shm_en = core_mmu_nsec_ddr_is_defined();
 	if (dyn_shm_en)

diff --git a/core/include/optee_rpc_cmd.h b/core/include/optee_rpc_cmd.h
@@ -182,6 +182,18 @@
  * Definition of protocol for command OPTEE_RPC_CMD_FS
  */
 
+/*
+ * Send an OCALL to the Client Application
+ *
+ * [in]     value[0].a	    CA Command ID (i.e., OCALL# for the CA to execute)
+ * [out]    value[0].b	    OCALL return value
+ * [out]    value[0].c	    OCALL return value origin
+ * [in]     value[1].a	    UUID of TA whence OCALL originated (HI bits)
+ * [out]    value[1].b	    UUID of TA whence OCALL originated (LO bits)
+ * [in/out] any[2..5].*	    OCALL parameters as specified by the TA, if any
+ */
+#define OPTEE_RPC_CMD_OCALL		22
+
 /*
  * Open a file
  *

diff --git a/mk/config.mk b/mk/config.mk
@@ -746,6 +746,13 @@ CFG_DRIVERS_RSTCTRL ?= n
 # configuration.
 CFG_WARN_INSECURE ?= y
 
+# CFG_CORE_OCALL=y enables support for OCALLs, allowing core to return
+# from an session or command invocation with an Ocall RPC context.
+CFG_CORE_OCALL ?= n
+ifeq ($(CFG_CORE_SEL1_SPMC)-$(CFG_CORE_OCALL),y-y)
+$(error "SPMC at SEL-1 does not comply with CFG_CORE_OCALL=y")
+endif
+
 # Enables warnings for declarations mixed with statements
 CFG_WARN_DECL_AFTER_STATEMENT ?= y