firmware: imx: Add i.MX95 SCMI CPU driver

The i.MX95 System manager exports SCMI CPU protocol for linux to manage
cpu cores. The driver is to use the cpu Protocol interface to
start, stop a cpu cores (eg, M7).

Reviewed-by: Cristian Marussi <cristian.marussi@arm.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Message-Id: <20250408-imx-lmm-cpu-v4-6-4c5f4a456e49@nxp.com>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>

diff --git a/drivers/firmware/arm_scmi/vendors/imx/Kconfig b/drivers/firmware/arm_scmi/vendors/imx/Kconfig
index 0a396d36262872d10ecb5be72d3dc855bf834165..c34c8c837441d55cbaac96f5465659e620db8618 100644 (file)
--- a/drivers/firmware/arm_scmi/vendors/imx/Kconfig
+++ b/drivers/firmware/arm_scmi/vendors/imx/Kconfig
@@ -15,6 +15,7 @@ config IMX_SCMI_BBM_EXT
 config IMX_SCMI_CPU_EXT
        tristate "i.MX SCMI CPU EXTENSION"
        depends on ARM_SCMI_PROTOCOL || (COMPILE_TEST && OF)
+       depends on IMX_SCMI_CPU_DRV
        default y if ARCH_MXC
        help
          This enables i.MX System CPU Protocol to manage cpu

diff --git a/drivers/firmware/imx/Kconfig b/drivers/firmware/imx/Kconfig
index cd4bf996fe612c1ce7f8cda5a38b05335948377b..127ad752acf86d104bcc0f4e609dca9c7ba2b417 100644 (file)
--- 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_CPU_DRV
+       tristate "IMX SCMI CPU Protocol driver"
+       depends on ARCH_MXC || 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 cpu management features.
+
+         This driver can also be built as a module.
+
 config IMX_SCMI_LMM_DRV
        tristate "IMX SCMI LMM Protocol driver"
        depends on ARCH_MXC || COMPILE_TEST

diff --git a/drivers/firmware/imx/Makefile b/drivers/firmware/imx/Makefile
index 7762855d2a771169d4f1867d27e0d51be7c9ad03..3bbaffa6e3478112638ed031375602389f18ef09 100644 (file)
--- a/drivers/firmware/imx/Makefile
+++ b/drivers/firmware/imx/Makefile
@@ -1,5 +1,6 @@
 # SPDX-License-Identifier: GPL-2.0
 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-${CONFIG_IMX_SCMI_CPU_DRV} += sm-cpu.o
 obj-${CONFIG_IMX_SCMI_MISC_DRV}        += sm-misc.o
 obj-${CONFIG_IMX_SCMI_LMM_DRV} += sm-lmm.o

diff --git a/drivers/firmware/imx/sm-cpu.c b/drivers/firmware/imx/sm-cpu.c
new file mode 100644 (file)
index 0000000..091b014
--- /dev/null
+++ b/drivers/firmware/imx/sm-cpu.c
@@ -0,0 +1,85 @@
+// 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_cpu_proto_ops *imx_cpu_ops;
+static struct scmi_protocol_handle *ph;
+
+int scmi_imx_cpu_reset_vector_set(u32 cpuid, u64 vector, bool start, bool boot,
+                                 bool resume)
+{
+       if (!ph)
+               return -EPROBE_DEFER;
+
+       return imx_cpu_ops->cpu_reset_vector_set(ph, cpuid, vector, start,
+                                                boot, resume);
+}
+EXPORT_SYMBOL(scmi_imx_cpu_reset_vector_set);
+
+int scmi_imx_cpu_start(u32 cpuid, bool start)
+{
+       if (!ph)
+               return -EPROBE_DEFER;
+
+       if (start)
+               return imx_cpu_ops->cpu_start(ph, cpuid, true);
+
+       return imx_cpu_ops->cpu_start(ph, cpuid, false);
+};
+EXPORT_SYMBOL(scmi_imx_cpu_start);
+
+int scmi_imx_cpu_started(u32 cpuid, bool *started)
+{
+       if (!ph)
+               return -EPROBE_DEFER;
+
+       if (!started)
+               return -EINVAL;
+
+       return imx_cpu_ops->cpu_started(ph, cpuid, started);
+};
+EXPORT_SYMBOL(scmi_imx_cpu_started);
+
+static int scmi_imx_cpu_probe(struct scmi_device *sdev)
+{
+       const struct scmi_handle *handle = sdev->handle;
+
+       if (!handle)
+               return -ENODEV;
+
+       if (imx_cpu_ops) {
+               dev_err(&sdev->dev, "sm cpu already initialized\n");
+               return -EEXIST;
+       }
+
+       imx_cpu_ops = handle->devm_protocol_get(sdev, SCMI_PROTOCOL_IMX_CPU, &ph);
+       if (IS_ERR(imx_cpu_ops))
+               return PTR_ERR(imx_cpu_ops);
+
+       return 0;
+}
+
+static const struct scmi_device_id scmi_id_table[] = {
+       { SCMI_PROTOCOL_IMX_CPU, "imx-cpu" },
+       { },
+};
+MODULE_DEVICE_TABLE(scmi, scmi_id_table);
+
+static struct scmi_driver scmi_imx_cpu_driver = {
+       .name = "scmi-imx-cpu",
+       .probe = scmi_imx_cpu_probe,
+       .id_table = scmi_id_table,
+};
+module_scmi_driver(scmi_imx_cpu_driver);
+
+MODULE_AUTHOR("Peng Fan <peng.fan@nxp.com>");
+MODULE_DESCRIPTION("IMX SM CPU driver");
+MODULE_LICENSE("GPL");

diff --git a/include/linux/firmware/imx/sm.h b/include/linux/firmware/imx/sm.h
index bc27b04afb2f68b048955f51c07a106f4c7e5852..a8a17eeb7d907ef8ac074c4ed1d3ac83f1104627 100644 (file)
--- a/include/linux/firmware/imx/sm.h
+++ b/include/linux/firmware/imx/sm.h
@@ -21,6 +21,11 @@
 int scmi_imx_misc_ctrl_get(u32 id, u32 *num, u32 *val);
 int scmi_imx_misc_ctrl_set(u32 id, u32 val);
 
+int scmi_imx_cpu_start(u32 cpuid, bool start);
+int scmi_imx_cpu_started(u32 cpuid, bool *started);
+int scmi_imx_cpu_reset_vector_set(u32 cpuid, u64 vector, bool start, bool boot,
+                                 bool resume);
+
 enum scmi_imx_lmm_op {
        SCMI_IMX_LMM_BOOT,
        SCMI_IMX_LMM_POWER_ON,