root/drivers/firmware/arm_scmi/vendors/imx/imx-sm-lmm.c
// SPDX-License-Identifier: GPL-2.0
/*
 * System control and Management Interface (SCMI) NXP LMM Protocol
 *
 * Copyright 2025 NXP
 */

#include <linux/bits.h>
#include <linux/io.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>

#include "../../protocols.h"
#include "../../notify.h"

#define SCMI_PROTOCOL_SUPPORTED_VERSION         0x10000

enum scmi_imx_lmm_protocol_cmd {
        SCMI_IMX_LMM_ATTRIBUTES = 0x3,
        SCMI_IMX_LMM_BOOT = 0x4,
        SCMI_IMX_LMM_RESET = 0x5,
        SCMI_IMX_LMM_SHUTDOWN = 0x6,
        SCMI_IMX_LMM_WAKE = 0x7,
        SCMI_IMX_LMM_SUSPEND = 0x8,
        SCMI_IMX_LMM_NOTIFY = 0x9,
        SCMI_IMX_LMM_RESET_REASON = 0xA,
        SCMI_IMX_LMM_POWER_ON = 0xB,
        SCMI_IMX_LMM_RESET_VECTOR_SET = 0xC,
};

struct scmi_imx_lmm_priv {
        u32 nr_lmm;
};

#define SCMI_IMX_LMM_NR_LM_MASK GENMASK(5, 0)
#define SCMI_IMX_LMM_NR_MAX     16
struct scmi_msg_imx_lmm_protocol_attributes {
        __le32 attributes;
};

struct scmi_msg_imx_lmm_attributes_out {
        __le32 lmid;
        __le32 attributes;
        __le32 state;
        __le32 errstatus;
        u8 name[LMM_MAX_NAME];
};

struct scmi_imx_lmm_reset_vector_set_in {
        __le32 lmid;
        __le32 cpuid;
        __le32 flags; /* reserved for future extension */
        __le32 resetvectorlow;
        __le32 resetvectorhigh;
};

struct scmi_imx_lmm_shutdown_in {
        __le32 lmid;
#define SCMI_IMX_LMM_SHUTDOWN_GRACEFUL  BIT(0)
        __le32 flags;
};

static int scmi_imx_lmm_validate_lmid(const struct scmi_protocol_handle *ph, u32 lmid)
{
        struct scmi_imx_lmm_priv *priv = ph->get_priv(ph);

        if (lmid >= priv->nr_lmm)
                return -EINVAL;

        return 0;
}

static int scmi_imx_lmm_attributes(const struct scmi_protocol_handle *ph,
                                   u32 lmid, struct scmi_imx_lmm_info *info)
{
        struct scmi_msg_imx_lmm_attributes_out *out;
        struct scmi_xfer *t;
        int ret;

        ret = ph->xops->xfer_get_init(ph, SCMI_IMX_LMM_ATTRIBUTES, sizeof(u32), 0, &t);
        if (ret)
                return ret;

        put_unaligned_le32(lmid, t->tx.buf);
        ret = ph->xops->do_xfer(ph, t);
        if (!ret) {
                out = t->rx.buf;
                info->lmid = le32_to_cpu(out->lmid);
                info->state = le32_to_cpu(out->state);
                info->errstatus = le32_to_cpu(out->errstatus);
                strscpy(info->name, out->name);
                dev_dbg(ph->dev, "i.MX LMM: Logical Machine(%d), name: %s\n",
                        info->lmid, info->name);
        } else {
                dev_err(ph->dev, "i.MX LMM: Failed to get info of Logical Machine(%u)\n", lmid);
        }

        ph->xops->xfer_put(ph, t);

        return ret;
}

static int
scmi_imx_lmm_power_boot(const struct scmi_protocol_handle *ph, u32 lmid, bool boot)
{
        struct scmi_xfer *t;
        u8 msg_id;
        int ret;

        ret = scmi_imx_lmm_validate_lmid(ph, lmid);
        if (ret)
                return ret;

        if (boot)
                msg_id = SCMI_IMX_LMM_BOOT;
        else
                msg_id = SCMI_IMX_LMM_POWER_ON;

        ret = ph->xops->xfer_get_init(ph, msg_id, sizeof(u32), 0, &t);
        if (ret)
                return ret;

        put_unaligned_le32(lmid, t->tx.buf);
        ret = ph->xops->do_xfer(ph, t);

        ph->xops->xfer_put(ph, t);

        return ret;
}

static int scmi_imx_lmm_reset_vector_set(const struct scmi_protocol_handle *ph,
                                         u32 lmid, u32 cpuid, u32 flags, u64 vector)
{
        struct scmi_imx_lmm_reset_vector_set_in *in;
        struct scmi_xfer *t;
        int ret;

        ret = ph->xops->xfer_get_init(ph, SCMI_IMX_LMM_RESET_VECTOR_SET, sizeof(*in),
                                      0, &t);
        if (ret)
                return ret;

        in = t->tx.buf;
        in->lmid = cpu_to_le32(lmid);
        in->cpuid = cpu_to_le32(cpuid);
        in->flags = cpu_to_le32(0);
        in->resetvectorlow = cpu_to_le32(lower_32_bits(vector));
        in->resetvectorhigh = cpu_to_le32(upper_32_bits(vector));
        ret = ph->xops->do_xfer(ph, t);

        ph->xops->xfer_put(ph, t);

        return ret;
}

static int scmi_imx_lmm_shutdown(const struct scmi_protocol_handle *ph, u32 lmid,
                                 u32 flags)
{
        struct scmi_imx_lmm_shutdown_in *in;
        struct scmi_xfer *t;
        int ret;

        ret = scmi_imx_lmm_validate_lmid(ph, lmid);
        if (ret)
                return ret;

        ret = ph->xops->xfer_get_init(ph, SCMI_IMX_LMM_SHUTDOWN, sizeof(*in),
                                      0, &t);
        if (ret)
                return ret;

        in = t->tx.buf;
        in->lmid = cpu_to_le32(lmid);
        if (flags & SCMI_IMX_LMM_SHUTDOWN_GRACEFUL)
                in->flags = cpu_to_le32(SCMI_IMX_LMM_SHUTDOWN_GRACEFUL);
        else
                in->flags = cpu_to_le32(0);
        ret = ph->xops->do_xfer(ph, t);

        ph->xops->xfer_put(ph, t);

        return ret;
}

static const struct scmi_imx_lmm_proto_ops scmi_imx_lmm_proto_ops = {
        .lmm_power_boot = scmi_imx_lmm_power_boot,
        .lmm_info = scmi_imx_lmm_attributes,
        .lmm_reset_vector_set = scmi_imx_lmm_reset_vector_set,
        .lmm_shutdown = scmi_imx_lmm_shutdown,
};

static int scmi_imx_lmm_protocol_attributes_get(const struct scmi_protocol_handle *ph,
                                                struct scmi_imx_lmm_priv *priv)
{
        struct scmi_msg_imx_lmm_protocol_attributes *attr;
        struct scmi_xfer *t;
        int ret;

        ret = ph->xops->xfer_get_init(ph, PROTOCOL_ATTRIBUTES, 0,
                                      sizeof(*attr), &t);
        if (ret)
                return ret;

        attr = t->rx.buf;

        ret = ph->xops->do_xfer(ph, t);
        if (!ret) {
                priv->nr_lmm = le32_get_bits(attr->attributes, SCMI_IMX_LMM_NR_LM_MASK);
                if (priv->nr_lmm > SCMI_IMX_LMM_NR_MAX) {
                        dev_err(ph->dev, "i.MX LMM: %d:Exceed max supported Logical Machines\n",
                                priv->nr_lmm);
                        ret = -EINVAL;
                } else {
                        dev_info(ph->dev, "i.MX LMM: %d Logical Machines\n", priv->nr_lmm);
                }
        }

        ph->xops->xfer_put(ph, t);

        return ret;
}

static int scmi_imx_lmm_protocol_init(const struct scmi_protocol_handle *ph)
{
        struct scmi_imx_lmm_priv *info;
        int ret;

        dev_info(ph->dev, "NXP SM LMM Version %d.%d\n",
                 PROTOCOL_REV_MAJOR(ph->version), PROTOCOL_REV_MINOR(ph->version));

        info = devm_kzalloc(ph->dev, sizeof(*info), GFP_KERNEL);
        if (!info)
                return -ENOMEM;

        ret = scmi_imx_lmm_protocol_attributes_get(ph, info);
        if (ret)
                return ret;

        return ph->set_priv(ph, info);
}

static const struct scmi_protocol scmi_imx_lmm = {
        .id = SCMI_PROTOCOL_IMX_LMM,
        .owner = THIS_MODULE,
        .instance_init = &scmi_imx_lmm_protocol_init,
        .ops = &scmi_imx_lmm_proto_ops,
        .supported_version = SCMI_PROTOCOL_SUPPORTED_VERSION,
        .vendor_id = SCMI_IMX_VENDOR,
        .sub_vendor_id = SCMI_IMX_SUBVENDOR,
};
module_scmi_protocol(scmi_imx_lmm);

MODULE_ALIAS("scmi-protocol-" __stringify(SCMI_PROTOCOL_IMX_LMM) "-" SCMI_IMX_VENDOR);
MODULE_DESCRIPTION("i.MX SCMI LMM driver");
MODULE_LICENSE("GPL");