[PATCH v3 5/7] firmware: imx: Add i.MX95 SCMI LMM driver

Peng Fan (OSS)
2025-03-03T02:55:01Z

From: Peng Fan <peng.fan@nxp.com>

The i.MX95 System manager exports SCMI LMM protocol for linux to manage
Logical Machines. The driver is to use the LMM Protocol interface to
boot, shutdown a LM.

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
drivers/firmware/arm_scmi/vendors/imx/Kconfig | 3 +-
drivers/firmware/imx/Kconfig | 11 ++++
drivers/firmware/imx/Makefile | 1 +
drivers/firmware/imx/sm-lmm.c | 91 +++++++++++++++++++++++++++
include/linux/firmware/imx/sm.h | 14 +++++
5 files changed, 119 insertions(+), 1 deletion(-)

diff --git a/drivers/firmware/arm_scmi/vendors/imx/Kconfig b/drivers/firmware/arm_scmi/vendors/imx/Kconfig
index b5f13d0e40155e485f4d1696e9550645d888ef44..4c24e17425f830810f8ba376ece9db93c8cded6d 100644
--- a/drivers/firmware/arm_scmi/vendors/imx/Kconfig
+++ b/drivers/firmware/arm_scmi/vendors/imx/Kconfig
@@ -26,7 +26,8 @@ config IMX_SCMI_CPU_EXT
config IMX_SCMI_LMM_EXT
tristate "i.MX SCMI LMM EXTENSION"
depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
- default y if ARCH_MXC
+ depends on IMX_SCMI_LMM_DRV
+ default y if ARCH_MXC && ARM64
help
This enables i.MX System Logical Machine Protocol to
manage Logical Machines boot, shutdown and etc.
diff --git a/drivers/firmware/imx/Kconfig b/drivers/firmware/imx/Kconfig
index c964f4924359fcd375560ee8263021b0fe65db1b..70c092424328067ea6b946cee59f072661e27e47 100644
--- a/drivers/firmware/imx/Kconfig
+++ b/drivers/firmware/imx/Kconfig
@@ -23,6 +23,17 @@ config IMX_SCU
This driver manages the IPC interface between host CPU and the
SCU firmware running on M4.

+config IMX_SCMI_LMM_DRV
+ tristate "IMX SCMI LMM Protocol driver"
+ depends on ARCH_MXC && ARM64 || COMPILE_TEST
+ default y if ARCH_MXC && ARM64
+ help
+ The System Controller Management Interface firmware (SCMI FW) is
+ a low-level system function which runs on a dedicated Cortex-M
+ core that could provide Logical Machine management features.
+
+ This driver can also be built as a module.
+
config IMX_SCMI_MISC_DRV
tristate "IMX SCMI MISC Protocol driver"
depends on ARCH_MXC || COMPILE_TEST
diff --git a/drivers/firmware/imx/Makefile b/drivers/firmware/imx/Makefile
index 8d046c341be878bb6dd1e6277992ff66ae90e292..7762855d2a771169d4f1867d27e0d51be7c9ad03 100644
--- a/drivers/firmware/imx/Makefile
+++ b/drivers/firmware/imx/Makefile
@@ -2,3 +2,4 @@
obj-$(CONFIG_IMX_DSP) += imx-dsp.o
obj-$(CONFIG_IMX_SCU) += imx-scu.o misc.o imx-scu-irq.o rm.o imx-scu-soc.o
obj-${CONFIG_IMX_SCMI_MISC_DRV} += sm-misc.o
+obj-${CONFIG_IMX_SCMI_LMM_DRV} += sm-lmm.o
diff --git a/drivers/firmware/imx/sm-lmm.c b/drivers/firmware/imx/sm-lmm.c
new file mode 100644
index 0000000000000000000000000000000000000000..6807bf563c03d21a68022ecf3469c38bee4fc2f5
--- /dev/null
+++ b/drivers/firmware/imx/sm-lmm.c
@@ -0,0 +1,91 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright 2025 NXP
+ */
+
+#include <linux/firmware/imx/sm.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/scmi_protocol.h>
+#include <linux/scmi_imx_protocol.h>
+
+static const struct scmi_imx_lmm_proto_ops *imx_lmm_ops;
+static struct scmi_protocol_handle *ph;
+
+int scmi_imx_lmm_info(u32 lmid, struct scmi_imx_lmm_info *info)
+{
+ if (!ph)
+ return -EPROBE_DEFER;
+
+ if (!info)
+ return -EINVAL;
+
+ return imx_lmm_ops->lmm_info(ph, lmid, info);
+};
+EXPORT_SYMBOL(scmi_imx_lmm_info);
+
+int scmi_imx_lmm_reset_vector_set(u32 lmid, u32 cpuid, u32 flags, u64 vector)
+{
+ if (!ph)
+ return -EPROBE_DEFER;
+
+ return imx_lmm_ops->lmm_reset_vector_set(ph, lmid, cpuid, flags, vector);
+}
+EXPORT_SYMBOL(scmi_imx_lmm_reset_vector_set);
+
+int scmi_imx_lmm_operation(u32 lmid, enum scmi_imx_lmm_op op, u32 flags)
+{
+ if (!ph)
+ return -EPROBE_DEFER;
+
+ switch (op) {
+ case SCMI_IMX_LMM_BOOT:
+ return imx_lmm_ops->lmm_power_boot(ph, lmid, true);
+ case SCMI_IMX_LMM_POWER_ON:
+ return imx_lmm_ops->lmm_power_boot(ph, lmid, false);
+ case SCMI_IMX_LMM_SHUTDOWN:
+ return imx_lmm_ops->lmm_shutdown(ph, lmid, flags);
+ default:
+ break;
+ }
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL(scmi_imx_lmm_operation);
+
+static int scmi_imx_lmm_probe(struct scmi_device *sdev)
+{
+ const struct scmi_handle *handle = sdev->handle;
+
+ if (!handle)
+ return -ENODEV;
+
+ if (imx_lmm_ops) {
+ dev_err(&sdev->dev, "lmm already initialized\n");
+ return -EEXIST;
+ }
+
+ imx_lmm_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_IMX_LMM, &ph);
+ if (IS_ERR(imx_lmm_ops))
+ return PTR_ERR(imx_lmm_ops);
+
+ return 0;
+}
+
+static const struct scmi_device_id scmi_id_table[] = {
+ { SCMI_PROTOCOL_IMX_LMM, "imx-lmm" },
+ { },
+};
+MODULE_DEVICE_TABLE(scmi, scmi_id_table);
+
+static struct scmi_driver scmi_imx_lmm_driver = {
+ .name = "scmi-imx-lmm",
+ .probe = scmi_imx_lmm_probe,
+ .id_table = scmi_id_table,
+};
+module_scmi_driver(scmi_imx_lmm_driver);
+
+MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>");
+MODULE_DESCRIPTION("IMX SM LMM driver");
+MODULE_LICENSE("GPL");
diff --git a/include/linux/firmware/imx/sm.h b/include/linux/firmware/imx/sm.h
index 9b85a3f028d1b0a5287b453eb3ad8412a363fe6c..bc27b04afb2f68b048955f51c07a106f4c7e5852 100644
--- a/include/linux/firmware/imx/sm.h
+++ b/include/linux/firmware/imx/sm.h
@@ -8,6 +8,7 @@

#include <linux/bitfield.h>
#include <linux/errno.h>
+#include <linux/scmi_imx_protocol.h>
#include <linux/types.h>

#define SCMI_IMX_CTRL_PDM_CLK_SEL 0 /* AON PDM clock sel */
@@ -20,4 +21,17 @@
int scmi_imx_misc_ctrl_get(u32 id, u32 *num, u32 *val);
int scmi_imx_misc_ctrl_set(u32 id, u32 val);

+enum scmi_imx_lmm_op {
+ SCMI_IMX_LMM_BOOT,
+ SCMI_IMX_LMM_POWER_ON,
+ SCMI_IMX_LMM_SHUTDOWN,
+};
+
+/* For shutdown pperation */
+#define SCMI_IMX_LMM_OP_FORCEFUL 0
+#define SCMI_IMX_LMM_OP_GRACEFUL BIT(0)
+
+int scmi_imx_lmm_operation(u32 lmid, enum scmi_imx_lmm_op op, u32 flags);
+int scmi_imx_lmm_info(u32 lmid, struct scmi_imx_lmm_info *info);
+int scmi_imx_lmm_reset_vector_set(u32 lmid, u32 cpuid, u32 flags, u64 vector);
#endif

--
2.37.1