[PATCH v7 09/15] firmware: arm_scmi: Make shmem support optional for transports

From: Igor Skalkin <>

Upcoming new SCMI transports won't need any kind of shared memory support.
Compile shmem.c only if a shmem based transport is selected.

Signed-off-by: Igor Skalkin <>
[ Peter: Adapted patch for submission to upstream. ]
Co-developed-by: Peter Hilber <>
Signed-off-by: Peter Hilber <>
[ Cristian: Adapted patch/commit_msg to new SCMI Kconfig layout ]
Signed-off-by: Cristian Marussi <>
---
v4 --> v5
- Adapted to new SCMI Kconfig layout
---
 drivers/firmware/arm_scmi/Kconfig  | 8 ++++++++
 drivers/firmware/arm_scmi/Makefile | 2 +-
 2 files changed, 9 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/Kconfig b/drivers/firmware/arm_scmi/Kconfig
index a6fcd06b2232..cd84e5f2ee02 100644
--- a/drivers/firmware/arm_scmi/Kconfig
+++ b/drivers/firmware/arm_scmi/Kconfig
@@ -30,10 +30,17 @@ config ARM_SCMI_HAVE_TRANSPORT
 	  Used to trigger a build bug when trying to build SCMI without any
 	  configured transport.
 
+config ARM_SCMI_HAVE_SHMEM
+	bool
+	help
+	  This declares whether a shared memory based transport for SCMI is
+	  available.
+
 config ARM_SCMI_TRANSPORT_MAILBOX
 	bool "SCMI transport based on Mailbox"
 	depends on MAILBOX
 	select ARM_SCMI_HAVE_TRANSPORT
+	select ARM_SCMI_HAVE_SHMEM
 	default y
 	help
 	  Enable mailbox based transport for SCMI.
@@ -45,6 +52,7 @@ config ARM_SCMI_TRANSPORT_SMC
 	bool "SCMI transport based on SMC"
 	depends on HAVE_ARM_SMCCC_DISCOVERY
 	select ARM_SCMI_HAVE_TRANSPORT
+	select ARM_SCMI_HAVE_SHMEM
 	default y
 	help
 	  Enable SMC based transport for SCMI.
diff --git a/drivers/firmware/arm_scmi/Makefile b/drivers/firmware/arm_scmi/Makefile
index 38163d6991b3..e0e6bd3dba9e 100644
--- a/drivers/firmware/arm_scmi/Makefile
+++ b/drivers/firmware/arm_scmi/Makefile
@@ -1,7 +1,7 @@
 # SPDX-License-Identifier: GPL-2.0-only
 scmi-bus-y = bus.o
 scmi-driver-y = driver.o notify.o
-scmi-transport-y = shmem.o
+scmi-transport-$(CONFIG_ARM_SCMI_HAVE_SHMEM) = shmem.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_MAILBOX) += mailbox.o
 scmi-transport-$(CONFIG_ARM_SCMI_TRANSPORT_SMC) += smc.o
 scmi-protocols-y = base.o clock.o perf.o power.o reset.o sensors.o system.o voltage.o
-- 
2.17.1