[PATCH v7 01/19] firmware: scmi: smt: Interrupt communication enable

Alice Guo (OSS)
2025-03-05T13:29:03Z

From: Viorel Suman <viorel.suman@nxp.com>

i.MX95 System Manager uses interrupt driven communication which requires
the caller to set Bit[0] of channel flags to 1. When transmission
completes and the previous general purpose interrupt has been processed
by the other core, i.MX95 System Manager will set General Purpose
Interrupt Control Register (GCR). U-Boot polls General-purpose Status
(GSR) to check if the operation is finished.

Signed-off-by: Viorel Suman <viorel.suman@nxp.com>
Signed-off-by: Alice Guo <alice.guo@nxp.com>
Reviewed-by: Ye Li <ye.li@nxp.com>
---
drivers/firmware/scmi/Kconfig | 6 ++++++
drivers/firmware/scmi/smt.c | 13 +++++++++++++
2 files changed, 19 insertions(+)

diff --git a/drivers/firmware/scmi/Kconfig b/drivers/firmware/scmi/Kconfig
index 8cf85f0d7a..eb62b88615 100644
--- a/drivers/firmware/scmi/Kconfig
+++ b/drivers/firmware/scmi/Kconfig
@@ -41,3 +41,9 @@ config SCMI_AGENT_OPTEE
help
Enable the SCMI communication channel based on OP-TEE transport
for compatible "linaro,scmi-optee".
+
+config SCMI_TRANSPORT_SMT_INTR
+ bool
+ depends on SCMI_FIRMWARE
+ help
+ Enable interrupt communication of shared memory based transport.
diff --git a/drivers/firmware/scmi/smt.c b/drivers/firmware/scmi/smt.c
index 67d2f45002..a0489f9718 100644
--- a/drivers/firmware/scmi/smt.c
+++ b/drivers/firmware/scmi/smt.c
@@ -20,6 +20,16 @@

#include "smt.h"

+static void scmi_smt_enable_intr(struct scmi_smt *smt, bool enable)
+{
+ struct scmi_smt_header *hdr = (void *)smt->buf;
+
+ if (enable)
+ hdr->flags |= SCMI_SHMEM_FLAG_INTR_ENABLED;
+ else
+ hdr->flags &= ~SCMI_SHMEM_FLAG_INTR_ENABLED;
+}
+
/**
* Get shared memory configuration defined by the referred DT phandle
* Return with a errno compliant value.
@@ -48,6 +58,9 @@ int scmi_dt_get_smt_buffer(struct udevice *dev, struct scmi_smt *smt)
if (!smt->buf)
return -ENOMEM;

+ if (IS_ENABLED(CONFIG_SCMI_TRANSPORT_SMT_INTR))
+ scmi_smt_enable_intr(smt, true);
+
#ifdef CONFIG_ARM
if (dcache_status())
mmu_set_region_dcache_behaviour(ALIGN_DOWN((uintptr_t)smt->buf, MMU_SECTION_SIZE),

--
2.43.0