[PATCH 4/5] firmware: imx: Add i.MX95 SCMI LMM driver

["Peng Fan (OSS)" <peng.fan@oss.nxp.com>]

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.

Signed-off-by: Peng Fan <peng.fan@nxp.com>
---
 drivers/firmware/imx/Kconfig    | 11 +++++
 drivers/firmware/imx/Makefile   |  1 +
 drivers/firmware/imx/sm-lmm.c   | 89 +++++++++++++++++++++++++++++++++++++++++
 include/linux/firmware/imx/sm.h | 27 +++++++++++++
 4 files changed, 128 insertions(+)

diff --git a/drivers/firmware/imx/Kconfig b/drivers/firmware/imx/Kconfig
index 907cd149c40a8b5f1b14c53e1c315ff4a28f32ac..c3e344d6ecc645df1f0e3ee8078934c47f347fd7 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 IMX_SCMI_LMM_EXT || COMPILE_TEST
+	default y if ARCH_MXC
+	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"
 	default y if ARCH_MXC
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..91a504e7f0d99089d3c2250a7918fb2fe99e991d
--- /dev/null
+++ b/drivers/firmware/imx/sm-lmm.c
@@ -0,0 +1,89 @@
+// 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_boot(u32 lmid)
+{
+	if (!ph)
+		return -EPROBE_DEFER;
+
+	return imx_lmm_ops->lmm_boot(ph, lmid);
+};
+EXPORT_SYMBOL(scmi_imx_lmm_boot);
+
+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_power_on(u32 lmid)
+{
+	if (!ph)
+		return -EPROBE_DEFER;
+
+	return imx_lmm_ops->lmm_power_on(ph, lmid);
+};
+EXPORT_SYMBOL(scmi_imx_lmm_power_on);
+
+int scmi_imx_lmm_shutdown(u32 lmid, u32 flags)
+{
+	if (!ph)
+		return -EPROBE_DEFER;
+
+	return imx_lmm_ops->lmm_shutdown(ph, lmid, flags);
+};
+EXPORT_SYMBOL(scmi_imx_lmm_shutdown);
+
+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..1e58ffaa81acd757d9e6a992a2f2df663681c08a 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 +21,30 @@
 int scmi_imx_misc_ctrl_get(u32 id, u32 *num, u32 *val);
 int scmi_imx_misc_ctrl_set(u32 id, u32 val);
 
+#if IS_ENABLED(CONFIG_IMX_SCMI_LMM_DRV) || IS_ENABLED(CONFIG_COMPILE_TEST)
+int scmi_imx_lmm_boot(u32 lmid);
+int scmi_imx_lmm_info(u32 lmid, struct scmi_imx_lmm_info *info);
+int scmi_imx_lmm_power_on(u32 lmid);
+int scmi_imx_lmm_shutdown(u32 lmid, u32 flags);
+#else
+static inline int scmi_imx_lmm_boot(u32 lmid)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int scmi_imx_lmm_info(u32 lmid, struct scmi_imx_lmm_info *info)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int scmi_imx_lmm_power_on(u32 lmid)
+{
+	return -EOPNOTSUPP;
+}
+
+static inline int scmi_imx_lmm_shutdown(u32 lmid, u32 flags)
+{
+	return -EOPNOTSUPP;
+}
+#endif
 #endif

-- 
2.37.1