// SPDX-License-Identifier: (GPL-2.0-only OR BSD-3-Clause)
//
// This file is provided under a dual BSD/GPLv2 license.  When using or
// redistributing this file, you may do so under either license.
//
// Copyright(c) 2018-2023 Intel Corporation
//

#include <linux/debugfs.h>
#include <linux/io.h>
#include <linux/pm_runtime.h>
#include <sound/sof/debug.h>
#include <sound/sof/ipc4/header.h>
#include "sof-priv.h"
#include "ops.h"
#include "ipc4-telemetry.h"
#include "ipc4-priv.h"

static void __iomem *sof_ipc4_query_exception_address(struct snd_sof_dev *sdev)
{
        u32 type = SOF_IPC4_DEBUG_SLOT_TELEMETRY;
        size_t telemetry_slot_offset;
        u32 offset;

        telemetry_slot_offset = sof_ipc4_find_debug_slot_offset_by_type(sdev, type);
        if (!telemetry_slot_offset)
                return NULL;

        /* skip the first separator magic number */
        offset = telemetry_slot_offset + sizeof(u32);

        return sdev->bar[sdev->mailbox_bar] + offset;
}

static ssize_t sof_telemetry_entry_read(struct file *file, char __user *buffer,
                                        size_t count, loff_t *ppos)
{
        struct snd_sof_dfsentry *dfse = file->private_data;
        struct snd_sof_dev *sdev = dfse->sdev;
        void __iomem *io_addr;
        loff_t pos = *ppos;
        size_t size_ret;
        u8 *buf;

        if (pos < 0)
                return -EINVAL;
        /* skip the first separator magic number */
        if (pos >= SOF_IPC4_DEBUG_SLOT_SIZE - 4 || !count)
                return 0;
        if (count > SOF_IPC4_DEBUG_SLOT_SIZE - 4 - pos)
                count = SOF_IPC4_DEBUG_SLOT_SIZE - 4 - pos;

        io_addr = sof_ipc4_query_exception_address(sdev);
        if (!io_addr)
                return -EFAULT;

        buf = kzalloc(SOF_IPC4_DEBUG_SLOT_SIZE - 4, GFP_KERNEL);
        if (!buf)
                return -ENOMEM;

        memcpy_fromio(buf, io_addr, SOF_IPC4_DEBUG_SLOT_SIZE - 4);
        size_ret = copy_to_user(buffer, buf + pos, count);
        if (size_ret) {
                kfree(buf);
                return -EFAULT;
        }

        *ppos = pos + count;
        kfree(buf);

        return count;
}

static const struct file_operations sof_telemetry_fops = {
        .open = simple_open,
        .read = sof_telemetry_entry_read,
};

void sof_ipc4_create_exception_debugfs_node(struct snd_sof_dev *sdev)
{
        struct snd_sof_dfsentry *dfse;

        dfse = devm_kzalloc(sdev->dev, sizeof(*dfse), GFP_KERNEL);
        if (!dfse)
                return;

        dfse->type = SOF_DFSENTRY_TYPE_IOMEM;
        dfse->size = SOF_IPC4_DEBUG_SLOT_SIZE - 4;
        dfse->access_type = SOF_DEBUGFS_ACCESS_ALWAYS;
        dfse->sdev = sdev;

        list_add(&dfse->list, &sdev->dfsentry_list);

        debugfs_create_file("exception", 0444, sdev->debugfs_root, dfse, &sof_telemetry_fops);
}