From f6ffd3bf7b561d603b350dc0274121886193fef0 Mon Sep 17 00:00:00 2001
From: Arunachalam Ganapathy <arunachalam.ganapathy@arm.com>
Date: Wed, 16 Mar 2022 11:14:09 +0000
Subject: [PATCH 36/40] ANDROID: trusty: Make trusty transports configurable

With TRUSTY_SMC_TRANSPORT set to 'y', SMC based message passing and
memory sharing support will be compiled in to trusty core.

With TRUSTY_FFA_TRANSPORT set to 'y', FFA based message passing and
memory sharing support will be compiled in to trusty core. This
depends on ARM FF-A driver (ARM_FFA_TRANSPORT).

Enabling any of the transport sets config TRUSTY_HAVE_TRANSPORT to 'y'.
Not enabling any of the transport causes the build to break.

Signed-off-by: Arunachalam Ganapathy <arunachalam.ganapathy@arm.com>
Change-Id: Ib5bbf0d39202e6897700264d14371ae33101c1d1
Upstream-Status: Pending [Not submitted to upstream yet]
Signed-off-by: Rupinderjit Singh <rupinderjit.singh@arm.com
---
 drivers/trusty/Kconfig          | 30 ++++++++++++++++++++++++++++++
 drivers/trusty/Makefile         | 26 +++++++++++++++-----------
 drivers/trusty/trusty-private.h |  4 ++++
 drivers/trusty/trusty.c         |  7 +++++++
 4 files changed, 56 insertions(+), 11 deletions(-)

diff --git a/drivers/trusty/Kconfig b/drivers/trusty/Kconfig
index fcde7f097acf..260022e4595b 100644
--- a/drivers/trusty/Kconfig
+++ b/drivers/trusty/Kconfig
@@ -21,6 +21,36 @@ config TRUSTY
 
 if TRUSTY
 
+config TRUSTY_HAVE_TRANSPORT
+	bool
+	help
+	  If any of the Trusty transport is enabled then it sets this config
+	  option. This variable is used to break the build when none of the
+	  Trusty transports are enabled.
+
+config TRUSTY_SMC_TRANSPORT
+	bool "Trusty transport based on SMC"
+	select TRUSTY_HAVE_TRANSPORT
+	default n
+	help
+	  Enable SMC based transport for Trusty. This transport is required for
+	  Trusty API version <= TRUSTY_API_VERSION_MEM_OBJ.
+
+	  If you want to use legacy SMC based transport for sending Trusty
+	  messages to secure world, answer Y.
+
+config TRUSTY_FFA_TRANSPORT
+	bool "Trusty transport based on FFA"
+	select TRUSTY_HAVE_TRANSPORT
+	depends on ARM_FFA_TRANSPORT
+	default y
+	help
+	  Enable ARM FF-A based transport for Trusty. This transport is required
+	  for Trusty API version >= TRUSTY_API_VERSION_MEM_OBJ.
+
+	  If you want to use ARM FF-A based transport for sending Trusty messages
+	  to secure world, answer Y.
+
 config TRUSTY_IRQ
 	tristate "Trusty IRQ support"
 	default y
diff --git a/drivers/trusty/Makefile b/drivers/trusty/Makefile
index 797d61bf68ef..104a4d0ed35c 100644
--- a/drivers/trusty/Makefile
+++ b/drivers/trusty/Makefile
@@ -3,14 +3,18 @@
 # Makefile for trusty components
 #
 
-obj-$(CONFIG_TRUSTY)		+= trusty-core.o
-trusty-core-objs		+= trusty.o trusty-mem.o
-trusty-core-objs		+= trusty-smc.o
-trusty-core-objs		+= trusty-ffa.o
-trusty-core-$(CONFIG_ARM)	+= trusty-smc-arm.o
-trusty-core-$(CONFIG_ARM64)	+= trusty-smc-arm64.o
-obj-$(CONFIG_TRUSTY_IRQ)	+= trusty-irq.o
-obj-$(CONFIG_TRUSTY_LOG)	+= trusty-log.o
-obj-$(CONFIG_TRUSTY_TEST)	+= trusty-test.o
-obj-$(CONFIG_TRUSTY_VIRTIO)	+= trusty-virtio.o
-obj-$(CONFIG_TRUSTY_VIRTIO_IPC)	+= trusty-ipc.o
+obj-$(CONFIG_TRUSTY)				+= trusty-core.o
+trusty-core-objs				+= trusty.o
+trusty-arm-smc-$(CONFIG_ARM)			+= trusty-smc-arm.o
+trusty-arm-smc64-$(CONFIG_ARM64)		+= trusty-smc-arm64.o
+trusty-transport-$(CONFIG_TRUSTY_SMC_TRANSPORT) += trusty-smc.o
+trusty-transport-$(CONFIG_TRUSTY_SMC_TRANSPORT) += trusty-mem.o
+trusty-transport-$(CONFIG_TRUSTY_SMC_TRANSPORT) += $(trusty-arm-smc-y)
+trusty-transport-$(CONFIG_TRUSTY_SMC_TRANSPORT) += $(trusty-arm-smc64-y)
+trusty-transport-$(CONFIG_TRUSTY_FFA_TRANSPORT) += trusty-ffa.o
+trusty-core-objs				+= $(trusty-transport-y)
+obj-$(CONFIG_TRUSTY_IRQ)			+= trusty-irq.o
+obj-$(CONFIG_TRUSTY_LOG)			+= trusty-log.o
+obj-$(CONFIG_TRUSTY_TEST)			+= trusty-test.o
+obj-$(CONFIG_TRUSTY_VIRTIO)			+= trusty-virtio.o
+obj-$(CONFIG_TRUSTY_VIRTIO_IPC)			+= trusty-ipc.o
diff --git a/drivers/trusty/trusty-private.h b/drivers/trusty/trusty-private.h
index 2496f397e5d2..386ca9ae5af3 100644
--- a/drivers/trusty/trusty-private.h
+++ b/drivers/trusty/trusty-private.h
@@ -72,7 +72,11 @@ int trusty_init_api_version(struct trusty_state *s, struct device *dev,
 
 typedef const struct trusty_transport_desc *trusty_transports_t;
 
+#ifdef CONFIG_TRUSTY_SMC_TRANSPORT
 extern const struct trusty_transport_desc trusty_smc_transport;
+#endif
+#ifdef CONFIG_TRUSTY_FFA_TRANSPORT
 extern const struct trusty_transport_desc trusty_ffa_transport;
+#endif
 
 #endif /* _TRUSTY_PRIVATE_H */
diff --git a/drivers/trusty/trusty.c b/drivers/trusty/trusty.c
index 66273873f169..06698f3c67f9 100644
--- a/drivers/trusty/trusty.c
+++ b/drivers/trusty/trusty.c
@@ -684,8 +684,12 @@ static int trusty_remove(struct platform_device *pdev)
  *
  */
 static const trusty_transports_t trusty_transports[] = {
+#ifdef CONFIG_TRUSTY_SMC_TRANSPORT
 	&trusty_smc_transport,
+#endif
+#ifdef CONFIG_TRUSTY_FFA_TRANSPORT
 	&trusty_ffa_transport,
+#endif
 	NULL,
 };
 
@@ -708,6 +712,9 @@ static struct platform_driver trusty_driver = {
 
 static int __init trusty_driver_init(void)
 {
+	BUILD_BUG_ON_MSG(!IS_ENABLED(CONFIG_TRUSTY_HAVE_TRANSPORT),
+			 "Trusty transport not configured");
+
 	return platform_driver_register(&trusty_driver);
 }
 
-- 
2.34.1