--- /dev/null
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+//
+// Copyright 2020 NXP
+//
+// Author: Daniel Baluta <daniel.baluta@nxp.com>
+//
+// Hardware interface for audio DSP on i.MX8M
+
+#include <linux/firmware.h>
+#include <linux/of_platform.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+
+#include <linux/module.h>
+#include <sound/sof.h>
+#include <sound/sof/xtensa.h>
+#include <linux/firmware/imx/dsp.h>
+
+#include "../ops.h"
+
+#define MBOX_OFFSET    0x800000
+#define MBOX_SIZE      0x1000
+
+struct imx8m_priv {
+       struct device *dev;
+       struct snd_sof_dev *sdev;
+
+       /* DSP IPC handler */
+       struct imx_dsp_ipc *dsp_ipc;
+       struct platform_device *ipc_dev;
+};
+
+static void imx8m_get_reply(struct snd_sof_dev *sdev)
+{
+       struct snd_sof_ipc_msg *msg = sdev->msg;
+       struct sof_ipc_reply reply;
+       int ret = 0;
+
+       if (!msg) {
+               dev_warn(sdev->dev, "unexpected ipc interrupt\n");
+               return;
+       }
+
+       /* get reply */
+       sof_mailbox_read(sdev, sdev->host_box.offset, &reply, sizeof(reply));
+
+       if (reply.error < 0) {
+               memcpy(msg->reply_data, &reply, sizeof(reply));
+               ret = reply.error;
+       } else {
+               /* reply has correct size? */
+               if (reply.hdr.size != msg->reply_size) {
+                       dev_err(sdev->dev, "error: reply expected %zu got %u bytes\n",
+                               msg->reply_size, reply.hdr.size);
+                       ret = -EINVAL;
+               }
+
+               /* read the message */
+               if (msg->reply_size > 0)
+                       sof_mailbox_read(sdev, sdev->host_box.offset,
+                                        msg->reply_data, msg->reply_size);
+       }
+
+       msg->reply_error = ret;
+}
+
+static int imx8m_get_mailbox_offset(struct snd_sof_dev *sdev)
+{
+       return MBOX_OFFSET;
+}
+
+static int imx8m_get_window_offset(struct snd_sof_dev *sdev, u32 id)
+{
+       return MBOX_OFFSET;
+}
+
+static void imx8m_dsp_handle_reply(struct imx_dsp_ipc *ipc)
+{
+       struct imx8m_priv *priv = imx_dsp_get_data(ipc);
+       unsigned long flags;
+
+       spin_lock_irqsave(&priv->sdev->ipc_lock, flags);
+       imx8m_get_reply(priv->sdev);
+       snd_sof_ipc_reply(priv->sdev, 0);
+       spin_unlock_irqrestore(&priv->sdev->ipc_lock, flags);
+}
+
+static void imx8m_dsp_handle_request(struct imx_dsp_ipc *ipc)
+{
+       struct imx8m_priv *priv = imx_dsp_get_data(ipc);
+
+       snd_sof_ipc_msgs_rx(priv->sdev);
+}
+
+struct imx_dsp_ops imx8m_dsp_ops = {
+       .handle_reply           = imx8m_dsp_handle_reply,
+       .handle_request         = imx8m_dsp_handle_request,
+};
+
+static int imx8m_send_msg(struct snd_sof_dev *sdev, struct snd_sof_ipc_msg *msg)
+{
+       struct imx8m_priv *priv = (struct imx8m_priv *)sdev->private;
+
+       sof_mailbox_write(sdev, sdev->host_box.offset, msg->msg_data,
+                         msg->msg_size);
+       imx_dsp_ring_doorbell(priv->dsp_ipc, 0);
+
+       return 0;
+}
+
+/*
+ * DSP control.
+ */
+static int imx8m_run(struct snd_sof_dev *sdev)
+{
+       /* TODO: start DSP using Audio MIX bits */
+       return 0;
+}
+
+static int imx8m_probe(struct snd_sof_dev *sdev)
+{
+       struct platform_device *pdev =
+               container_of(sdev->dev, struct platform_device, dev);
+       struct device_node *np = pdev->dev.of_node;
+       struct device_node *res_node;
+       struct resource *mmio;
+       struct imx8m_priv *priv;
+       struct resource res;
+       u32 base, size;
+       int ret = 0;
+
+       priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+       if (!priv)
+               return -ENOMEM;
+
+       sdev->private = priv;
+       priv->dev = sdev->dev;
+       priv->sdev = sdev;
+
+       priv->ipc_dev = platform_device_register_data(sdev->dev, "imx-dsp",
+                                                     PLATFORM_DEVID_NONE,
+                                                     pdev, sizeof(*pdev));
+       if (IS_ERR(priv->ipc_dev))
+               return PTR_ERR(priv->ipc_dev);
+
+       priv->dsp_ipc = dev_get_drvdata(&priv->ipc_dev->dev);
+       if (!priv->dsp_ipc) {
+               /* DSP IPC driver not probed yet, try later */
+               ret = -EPROBE_DEFER;
+               dev_err(sdev->dev, "Failed to get drvdata\n");
+               goto exit_pdev_unregister;
+       }
+
+       imx_dsp_set_data(priv->dsp_ipc, priv);
+       priv->dsp_ipc->ops = &imx8m_dsp_ops;
+
+       /* DSP base */
+       mmio = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       if (mmio) {
+               base = mmio->start;
+               size = resource_size(mmio);
+       } else {
+               dev_err(sdev->dev, "error: failed to get DSP base at idx 0\n");
+               ret = -EINVAL;
+               goto exit_pdev_unregister;
+       }
+
+       sdev->bar[SOF_FW_BLK_TYPE_IRAM] = devm_ioremap(sdev->dev, base, size);
+       if (!sdev->bar[SOF_FW_BLK_TYPE_IRAM]) {
+               dev_err(sdev->dev, "failed to ioremap base 0x%x size 0x%x\n",
+                       base, size);
+               ret = -ENODEV;
+               goto exit_pdev_unregister;
+       }
+       sdev->mmio_bar = SOF_FW_BLK_TYPE_IRAM;
+
+       res_node = of_parse_phandle(np, "memory-region", 0);
+       if (!res_node) {
+               dev_err(&pdev->dev, "failed to get memory region node\n");
+               ret = -ENODEV;
+               goto exit_pdev_unregister;
+       }
+
+       ret = of_address_to_resource(res_node, 0, &res);
+       if (ret) {
+               dev_err(&pdev->dev, "failed to get reserved region address\n");
+               goto exit_pdev_unregister;
+       }
+
+       sdev->bar[SOF_FW_BLK_TYPE_SRAM] = devm_ioremap_wc(sdev->dev, res.start,
+                                                         res.end - res.start +
+                                                         1);
+       if (!sdev->bar[SOF_FW_BLK_TYPE_SRAM]) {
+               dev_err(sdev->dev, "failed to ioremap mem 0x%x size 0x%x\n",
+                       base, size);
+               ret = -ENOMEM;
+               goto exit_pdev_unregister;
+       }
+       sdev->mailbox_bar = SOF_FW_BLK_TYPE_SRAM;
+
+       /* set default mailbox offset for FW ready message */
+       sdev->dsp_box.offset = MBOX_OFFSET;
+
+       return 0;
+
+exit_pdev_unregister:
+       platform_device_unregister(priv->ipc_dev);
+       return ret;
+}
+
+static int imx8m_remove(struct snd_sof_dev *sdev)
+{
+       struct imx8m_priv *priv = (struct imx8m_priv *)sdev->private;
+
+       platform_device_unregister(priv->ipc_dev);
+
+       return 0;
+}
+
+/* on i.MX8 there is 1 to 1 match between type and BAR idx */
+static int imx8m_get_bar_index(struct snd_sof_dev *sdev, u32 type)
+{
+       return type;
+}
+
+static void imx8m_ipc_msg_data(struct snd_sof_dev *sdev,
+                              struct snd_pcm_substream *substream,
+                              void *p, size_t sz)
+{
+       sof_mailbox_read(sdev, sdev->dsp_box.offset, p, sz);
+}
+
+static int imx8m_ipc_pcm_params(struct snd_sof_dev *sdev,
+                               struct snd_pcm_substream *substream,
+                               const struct sof_ipc_pcm_params_reply *reply)
+{
+       return 0;
+}
+
+static struct snd_soc_dai_driver imx8m_dai[] = {
+{
+       .name = "sai-port",
+},
+};
+
+/* i.MX8 ops */
+struct snd_sof_dsp_ops sof_imx8m_ops = {
+       /* probe and remove */
+       .probe          = imx8m_probe,
+       .remove         = imx8m_remove,
+       /* DSP core boot */
+       .run            = imx8m_run,
+
+       /* Block IO */
+       .block_read     = sof_block_read,
+       .block_write    = sof_block_write,
+
+       /* ipc */
+       .send_msg       = imx8m_send_msg,
+       .fw_ready       = sof_fw_ready,
+       .get_mailbox_offset     = imx8m_get_mailbox_offset,
+       .get_window_offset      = imx8m_get_window_offset,
+
+       .ipc_msg_data   = imx8m_ipc_msg_data,
+       .ipc_pcm_params = imx8m_ipc_pcm_params,
+
+       /* module loading */
+       .load_module    = snd_sof_parse_module_memcpy,
+       .get_bar_index  = imx8m_get_bar_index,
+       /* firmware loading */
+       .load_firmware  = snd_sof_load_firmware_memcpy,
+
+       /* DAI drivers */
+       .drv = imx8m_dai,
+       .num_drv = 1, /* we have only 1 SAI interface on i.MX8M */
+};
+EXPORT_SYMBOL(sof_imx8m_ops);
+
+MODULE_LICENSE("Dual BSD/GPL");