[PATCH v2 5/5] firmware: imx: adds miscdev
Amit Singh Tomar
amitsinght at marvell.com
Mon Jun 3 09:22:44 PDT 2024
Hi,
>
> ----------------------------------------------------------------------
> Adds the driver for communication interface to secure-enclave,
> for exchanging messages with NXP secure enclave HW IP(s) like
> EdgeLock Enclave from:
> - User-Space Applications via character driver.
>
> ABI documentation for the NXP secure-enclave driver.
>
> User-space library using this driver:
> - i.MX Secure Enclave library:
> -- URL: https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_nxp-2Dimx_imx-2Dsecure-2Denclave.git&d=DwICAg&c=nKjWec2b6R0mOyPaz7xtfQ&r=V_GK7jRuCHDErm6txmgDK1-MbUihtnSQ3gPgB-A-JKU&m=8xuiz3OEyshbkzLQ6-G2afLkh7sVv9b_HkFaPJVBu4wjmgAowHGi90q5RTroZ2oy&s=xi3fO_c9z_t-zdk3LdTGgqJ6M-5OjRD6oj-ECiVQ40Q&e= ,
> - i.MX Secure Middle-Ware:
> -- URL: https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_nxp-2Dimx_imx-2Dsmw.git&d=DwICAg&c=nKjWec2b6R0mOyPaz7xtfQ&r=V_GK7jRuCHDErm6txmgDK1-MbUihtnSQ3gPgB-A-JKU&m=8xuiz3OEyshbkzLQ6-G2afLkh7sVv9b_HkFaPJVBu4wjmgAowHGi90q5RTroZ2oy&s=jPOlKXqt_GIZGMvMboOdjkwu3UTpZ7fwEFm8Ki5z0LE&e=
>
> Signed-off-by: Pankaj Gupta <pankaj.gupta at nxp.com>
> ---
> Documentation/ABI/testing/se-cdev | 42 +++
> drivers/firmware/imx/ele_common.c | 108 +++++-
> drivers/firmware/imx/ele_common.h | 3 +
> drivers/firmware/imx/se_ctrl.c | 689 ++++++++++++++++++++++++++++++++++++++
> drivers/firmware/imx/se_ctrl.h | 46 +++
> include/uapi/linux/se_ioctl.h | 88 +++++
> 6 files changed, 974 insertions(+), 2 deletions(-)
>
> diff --git a/Documentation/ABI/testing/se-cdev b/Documentation/ABI/testing/se-cdev
> new file mode 100644
> index 000000000000..699525af6b86
> --- /dev/null
> +++ b/Documentation/ABI/testing/se-cdev
> @@ -0,0 +1,42 @@
> +What: /dev/<se>_mu[0-9]+_ch[0-9]+
> +Date: May 2024
> +KernelVersion: 6.8
> +Contact: linux-imx at nxp.com, pankaj.gupta at nxp.com
> +Description:
> + NXP offers multiple hardware IP(s) for secure-enclaves like EdgeLock-
> + Enclave(ELE), SECO. The character device file-descriptors
> + /dev/<se>_mu*_ch* are the interface between user-space NXP's secure-
> + enclave shared-library and the kernel driver.
> +
> + The ioctl(2)-based ABI is defined and documented in
> + [include]<linux/firmware/imx/ele_mu_ioctl.h>
> + ioctl(s) are used primarily for:
> + - shared memory management
> + - allocation of I/O buffers
> + - get mu info
> + - setting a dev-ctx as receiver that is slave to fw
> + - get SoC info
> +
> + The following file operations are supported:
> +
> + open(2)
> + Currently the only useful flags are O_RDWR.
> +
> + read(2)
> + Every read() from the opened character device context is waiting on
> + wakeup_intruptible, that gets set by the registered mailbox callback
> + function; indicating a message received from the firmware on message-
> + unit.
> +
> + write(2)
> + Every write() to the opened character device context needs to acquire
> + mailbox_lock, before sending message on to the message unit.
> +
> + close(2)
> + Stops and free up the I/O contexts that was associated
> + with the file descriptor.
> +
> +Users: https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_nxp-2Dimx_imx-2Dsecure-2Denclave.git&d=DwICAg&c=nKjWec2b6R0mOyPaz7xtfQ&r=V_GK7jRuCHDErm6txmgDK1-MbUihtnSQ3gPgB-A-JKU&m=8xuiz3OEyshbkzLQ6-G2afLkh7sVv9b_HkFaPJVBu4wjmgAowHGi90q5RTroZ2oy&s=xi3fO_c9z_t-zdk3LdTGgqJ6M-5OjRD6oj-ECiVQ40Q&e= ,
> + https://urldefense.proofpoint.com/v2/url?u=https-3A__github.com_nxp-2Dimx_imx-2Dsmw.git&d=DwICAg&c=nKjWec2b6R0mOyPaz7xtfQ&r=V_GK7jRuCHDErm6txmgDK1-MbUihtnSQ3gPgB-A-JKU&m=8xuiz3OEyshbkzLQ6-G2afLkh7sVv9b_HkFaPJVBu4wjmgAowHGi90q5RTroZ2oy&s=jPOlKXqt_GIZGMvMboOdjkwu3UTpZ7fwEFm8Ki5z0LE&e=
> + crypto/skcipher,
> + drivers/nvmem/imx-ocotp-ele.c
> diff --git a/drivers/firmware/imx/ele_common.c b/drivers/firmware/imx/ele_common.c
> index c286c3d84d82..15fabc369b21 100644
> --- a/drivers/firmware/imx/ele_common.c
> +++ b/drivers/firmware/imx/ele_common.c
> @@ -78,12 +78,98 @@ int imx_ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, void *rx_msg)
> return err;
> }
>
> +int imx_ele_miscdev_msg_rcv(struct se_if_device_ctx *dev_ctx)
> +{
> + struct se_msg_hdr *header = {0};
> + int err;
> +
> + if (dev_ctx->priv->waiting_rsp_dev == dev_ctx)
> + lockdep_assert_held(&dev_ctx->priv->se_if_cmd_lock);
> +
> + err = wait_event_interruptible(dev_ctx->wq, dev_ctx->pending_hdr != 0);
> + if (err)
> + dev_err(dev_ctx->dev,
> + "%s: Err[0x%x]:Interrupted by signal.\n",
> + dev_ctx->miscdev.name, err);
> +
> + header = (struct se_msg_hdr *) dev_ctx->temp_resp;
> +
> + if (header->tag == dev_ctx->priv->rsp_tag) {
> + if (dev_ctx->priv->waiting_rsp_dev != dev_ctx)
> + dev_warn(dev_ctx->dev,
> + "%s: Device context waiting for response mismatch.\n",
> + dev_ctx->miscdev.name);
> + else
> + dev_ctx->priv->waiting_rsp_dev = NULL;
> +
> + mutex_unlock(&dev_ctx->priv->se_if_cmd_lock);
> + }
> +
> + return err;
> +}
> +
> +int imx_ele_miscdev_msg_send(struct se_if_device_ctx *dev_ctx,
> + void *tx_msg, int tx_msg_sz)
> +{
> + struct se_if_priv *priv = dev_ctx->priv;
> + struct se_msg_hdr *header;
> + int err;
> +
> + header = (struct se_msg_hdr *) tx_msg;
> +
> + /*
> + * Check that the size passed as argument matches the size
> + * carried in the message.
> + */
> + err = header->size << 2;
> +
> + if (err != tx_msg_sz) {
> + err = -EINVAL;
> + dev_err(priv->dev,
> + "%s: User buffer too small\n",
> + dev_ctx->miscdev.name);
> + goto exit;
> + }
> + /* Check the message is valid according to tags */
> + if (header->tag == priv->cmd_tag) {
> + mutex_lock(&priv->se_if_cmd_lock);
In the previous patch (4/5), you used 'guard' locks. Wouldn't it be
better to use them here as well, considering the lock handling seems a
bit dodgy (I mean, the way lock is released only under certain condition)?
> + priv->waiting_rsp_dev = dev_ctx;
> + } else if (header->tag == priv->rsp_tag) {
> + /* Check the device context can send the command */
> + if (dev_ctx != priv->cmd_receiver_dev) {
> + dev_err(priv->dev,
> + "%s: Channel not configured to send resp to FW.",
> + dev_ctx->miscdev.name);
> + err = -EPERM;
> + goto exit;
> + }
> + } else {
> + dev_err(priv->dev,
> + "%s: The message does not have a valid TAG\n",
> + dev_ctx->miscdev.name);
> + err = -EINVAL;
> + goto exit;
> + }
> + err = imx_ele_msg_send(priv, tx_msg);
> + if (err < 0) {
> + if (header->tag == priv->cmd_tag) {
> + priv->waiting_rsp_dev = NULL;
> + mutex_unlock(&dev_ctx->priv->se_if_cmd_lock);
> + }
> + } else
> + err = header->size << 2;
> +exit:
> + return err;
> +}
> +
> /*
> * Callback called by mailbox FW, when data is received.
> */
> void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
> {
> struct device *dev = mbox_cl->dev;
> + struct se_if_device_ctx *dev_ctx;
> + struct se_api_msg *rx_msg;
> struct se_if_priv *priv;
> struct se_msg_hdr *header;
>
> @@ -97,8 +183,15 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
>
> header = (struct se_msg_hdr *) msg;
>
> - if (header->tag == priv->rsp_tag) {
> - if (!priv->waiting_rsp_dev) {
> + /* Incoming command: wake up the receiver if any. */
> + if (header->tag == priv->cmd_tag) {
> + dev_dbg(dev, "Selecting cmd receiver\n");
> + dev_ctx = priv->cmd_receiver_dev;
> + } else if (header->tag == priv->rsp_tag) {
> + if (priv->waiting_rsp_dev) {
> + dev_dbg(dev, "Selecting rsp waiter\n");
> + dev_ctx = priv->waiting_rsp_dev;
> + } else {
> /*
> * Reading the EdgeLock Enclave response
> * to the command, sent by other
> @@ -116,6 +209,17 @@ void se_if_rx_callback(struct mbox_client *mbox_cl, void *msg)
> *((u32 *) header));
> return;
> }
> + /* Init reception */
> + rx_msg = kzalloc(header->size << 2, GFP_KERNEL);
> + if (rx_msg)
> + memcpy(rx_msg, msg, header->size << 2);
> +
> + dev_ctx->temp_resp = (u32 *)rx_msg;
> + dev_ctx->temp_resp_size = header->size;
> +
> + /* Allow user to read */
> + dev_ctx->pending_hdr = 1;
> + wake_up_interruptible(&dev_ctx->wq);
> }
>
> int validate_rsp_hdr(struct se_if_priv *priv,
> diff --git a/drivers/firmware/imx/ele_common.h b/drivers/firmware/imx/ele_common.h
> index 76777ac629d6..11b9b36d4fda 100644
> --- a/drivers/firmware/imx/ele_common.h
> +++ b/drivers/firmware/imx/ele_common.h
> @@ -12,6 +12,9 @@
> #define IMX_ELE_FW_DIR "imx/ele/"
>
> uint32_t plat_add_msg_crc(uint32_t *msg, uint32_t msg_len);
> +int imx_ele_miscdev_msg_rcv(struct se_if_device_ctx *priv);
> +int imx_ele_miscdev_msg_send(struct se_if_device_ctx *dev_ctx,
> + void *tx_msg, int tx_msg_sz);
> int imx_ele_msg_rcv(struct se_if_priv *priv);
> int imx_ele_msg_send(struct se_if_priv *priv, void *tx_msg);
> int imx_ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, void *rx_msg);
> diff --git a/drivers/firmware/imx/se_ctrl.c b/drivers/firmware/imx/se_ctrl.c
> index 0642d349b3d3..3acaecd8f3bc 100644
> --- a/drivers/firmware/imx/se_ctrl.c
> +++ b/drivers/firmware/imx/se_ctrl.c
> @@ -23,6 +23,7 @@
> #include <linux/slab.h>
> #include <linux/string.h>
> #include <linux/sys_soc.h>
> +#include <uapi/linux/se_ioctl.h>
>
> #include "ele_base_msg.h"
> #include "ele_common.h"
> @@ -232,6 +233,590 @@ static int imx_fetch_se_soc_info(struct device *dev)
> return 0;
> }
>
> +/*
> + * File operations for user-space
> + */
> +
> +/* Write a message to the MU. */
> +static ssize_t se_if_fops_write(struct file *fp, const char __user *buf,
> + size_t size, loff_t *ppos)
> +{
> + struct se_api_msg *tx_msg __free(kfree);
> + struct se_if_device_ctx *dev_ctx;
> + struct se_if_priv *priv;
> + int err;
> +
> + dev_ctx = container_of(fp->private_data,
> + struct se_if_device_ctx,
> + miscdev);
> + priv = dev_ctx->priv;
> + dev_dbg(priv->dev,
> + "%s: write from buf (%p)%zu, ppos=%lld\n",
> + dev_ctx->miscdev.name,
> + buf, size, ((ppos) ? *ppos : 0));
> +
> + if (down_interruptible(&dev_ctx->fops_lock))
> + return -EBUSY;
> +
> + if (dev_ctx->status != SE_IF_CTX_OPENED) {
> + err = -EINVAL;
> + goto exit;
> + }
> +
> + if (size < SE_MU_HDR_SZ) {
> + dev_err(priv->dev,
> + "%s: User buffer too small(%zu < %d)\n",
> + dev_ctx->miscdev.name,
> + size, SE_MU_HDR_SZ);
> + err = -ENOSPC;
> + goto exit;
> + }
> + tx_msg = memdup_user(buf, size);
> + if (!tx_msg) {
> + err = -ENOMEM;
> + goto exit;
> + }
> +
> + print_hex_dump_debug("from user ", DUMP_PREFIX_OFFSET, 4, 4,
> + tx_msg, size, false);
> +
> + err = imx_ele_miscdev_msg_send(dev_ctx, tx_msg, size);
> +
> +exit:
> + up(&dev_ctx->fops_lock);
> + return err;
> +}
> +
> +/*
> + * Read a message from the MU.
> + * Blocking until a message is available.
> + */
> +static ssize_t se_if_fops_read(struct file *fp, char __user *buf,
> + size_t size, loff_t *ppos)
> +{
> + struct se_if_device_ctx *dev_ctx;
> + struct se_buf_desc *b_desc;
> + struct se_if_priv *priv;
> + u32 size_to_copy;
> + int err;
> +
> + dev_ctx = container_of(fp->private_data,
> + struct se_if_device_ctx,
> + miscdev);
> + priv = dev_ctx->priv;
> + dev_dbg(priv->dev,
> + "%s: read to buf %p(%zu), ppos=%lld\n",
> + dev_ctx->miscdev.name,
> + buf, size, ((ppos) ? *ppos : 0));
> +
> + if (down_interruptible(&dev_ctx->fops_lock))
> + return -EBUSY;
> +
> + if (dev_ctx->status != SE_IF_CTX_OPENED) {
> + err = -EINVAL;
> + goto exit;
> + }
> +
> + err = imx_ele_miscdev_msg_rcv(dev_ctx);
> + if (err)
> + goto exit;
> +
> + /* Buffer containing the message from FW, is
> + * allocated in callback function.
> + * Check if buffer allocation failed.
> + */
> + if (!dev_ctx->temp_resp) {
> + err = -ENOMEM;
> + goto exit;
> + }
> +
> + dev_dbg(priv->dev,
> + "%s: %s %s\n",
> + dev_ctx->miscdev.name,
> + __func__,
> + "message received, start transmit to user");
> +
> + /*
> + * Check that the size passed as argument is larger than
> + * the one carried in the message.
> + */
> + size_to_copy = dev_ctx->temp_resp_size << 2;
> + if (size_to_copy > size) {
> + dev_dbg(priv->dev,
> + "%s: User buffer too small (%zu < %d)\n",
> + dev_ctx->miscdev.name,
> + size, size_to_copy);
> + size_to_copy = size;
> + }
> +
> + /*
> + * We may need to copy the output data to user before
> + * delivering the completion message.
> + */
> + while (!list_empty(&dev_ctx->pending_out)) {
> + b_desc = list_first_entry_or_null(&dev_ctx->pending_out,
> + struct se_buf_desc,
> + link);
> + if (!b_desc)
> + continue;
> +
> + if (b_desc->usr_buf_ptr && b_desc->shared_buf_ptr) {
> +
> + dev_dbg(priv->dev,
> + "%s: Copy output data to user\n",
> + dev_ctx->miscdev.name);
> + if (copy_to_user(b_desc->usr_buf_ptr,
> + b_desc->shared_buf_ptr,
> + b_desc->size)) {
> + dev_err(priv->dev,
> + "%s: Failure copying output data to user.",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + }
> + }
> +
> + if (b_desc->shared_buf_ptr)
> + memset(b_desc->shared_buf_ptr, 0, b_desc->size);
> +
> + __list_del_entry(&b_desc->link);
> + kfree(b_desc);
> + }
> +
> + /* Copy data from the buffer */
> + print_hex_dump_debug("to user ", DUMP_PREFIX_OFFSET, 4, 4,
> + dev_ctx->temp_resp, size_to_copy, false);
> + if (copy_to_user(buf, dev_ctx->temp_resp, size_to_copy)) {
> + dev_err(priv->dev,
> + "%s: Failed to copy to user\n",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + }
> +
> + err = size_to_copy;
> + kfree(dev_ctx->temp_resp);
> +
> + /* free memory allocated on the shared buffers. */
> + dev_ctx->secure_mem.pos = 0;
> + dev_ctx->non_secure_mem.pos = 0;
> +
> + dev_ctx->pending_hdr = 0;
> +
> +exit:
> + /*
> + * Clean the used Shared Memory space,
> + * whether its Input Data copied from user buffers, or
> + * Data received from FW.
> + */
> + while (!list_empty(&dev_ctx->pending_in) ||
> + !list_empty(&dev_ctx->pending_out)) {
> + if (!list_empty(&dev_ctx->pending_in))
> + b_desc = list_first_entry_or_null(&dev_ctx->pending_in,
> + struct se_buf_desc,
> + link);
> + else
> + b_desc = list_first_entry_or_null(&dev_ctx->pending_out,
> + struct se_buf_desc,
> + link);
> +
> + if (!b_desc)
> + continue;
> +
> + if (b_desc->shared_buf_ptr)
> + memset(b_desc->shared_buf_ptr, 0, b_desc->size);
> +
> + __list_del_entry(&b_desc->link);
> + kfree(b_desc);
> + }
> +
> + up(&dev_ctx->fops_lock);
> + return err;
> +}
> +
> +static int se_ioctl_get_mu_info(struct se_if_device_ctx *dev_ctx,
> + u64 arg)
> +{
> + struct se_if_priv *priv = dev_get_drvdata(dev_ctx->dev);
> + struct imx_se_node_info *if_node_info;
> + struct se_ioctl_get_if_info info;
> + int err = 0;
> +
> + if_node_info = (struct imx_se_node_info *)priv->info;
> +
> + info.se_if_id = if_node_info->se_if_id;
> + info.interrupt_idx = 0;
> + info.tz = 0;
> + info.did = if_node_info->se_if_did;
> + info.cmd_tag = if_node_info->cmd_tag;
> + info.rsp_tag = if_node_info->rsp_tag;
> + info.success_tag = if_node_info->success_tag;
> + info.base_api_ver = if_node_info->base_api_ver;
> + info.fw_api_ver = if_node_info->fw_api_ver;
> +
> + dev_dbg(priv->dev,
> + "%s: info [se_if_id: %d, irq_idx: %d, tz: 0x%x, did: 0x%x]\n",
> + dev_ctx->miscdev.name,
> + info.se_if_id, info.interrupt_idx, info.tz, info.did);
> +
> + if (copy_to_user((u8 *)arg, &info, sizeof(info))) {
> + dev_err(dev_ctx->priv->dev,
> + "%s: Failed to copy mu info to user\n",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + }
> +
> +exit:
> + return err;
> +}
> +
> +/*
> + * Copy a buffer of data to/from the user and return the address to use in
> + * messages
> + */
> +static int se_ioctl_setup_iobuf_handler(struct se_if_device_ctx *dev_ctx,
> + u64 arg)
> +{
> + struct se_shared_mem *shared_mem = NULL;
> + struct se_ioctl_setup_iobuf io = {0};
> + struct se_buf_desc *b_desc = NULL;
> + int err = 0;
> + u32 pos;
> +
> + if (copy_from_user(&io, (u8 *)arg, sizeof(io))) {
> + dev_err(dev_ctx->priv->dev,
> + "%s: Failed copy iobuf config from user\n",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + }
> +
> + dev_dbg(dev_ctx->priv->dev,
> + "%s: io [buf: %p(%d) flag: %x]\n",
> + dev_ctx->miscdev.name,
> + io.user_buf, io.length, io.flags);
> +
> + if (io.length == 0 || !io.user_buf) {
> + /*
> + * Accept NULL pointers since some buffers are optional
> + * in FW commands. In this case we should return 0 as
> + * pointer to be embedded into the message.
> + * Skip all data copy part of code below.
> + */
> + io.ele_addr = 0;
> + goto copy;
> + }
> +
> + /* Select the shared memory to be used for this buffer. */
> + if (io.flags & SE_MU_IO_FLAGS_USE_SEC_MEM) {
> + /* App requires to use secure memory for this buffer.*/
> + dev_err(dev_ctx->priv->dev,
> + "%s: Failed allocate SEC MEM memory\n",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + } else {
> + /* No specific requirement for this buffer. */
> + shared_mem = &dev_ctx->non_secure_mem;
> + }
> +
> + /* Check there is enough space in the shared memory. */
> + if (shared_mem->size < shared_mem->pos
> + || io.length >= shared_mem->size - shared_mem->pos) {
> + dev_err(dev_ctx->priv->dev,
> + "%s: Not enough space in shared memory\n",
> + dev_ctx->miscdev.name);
> + err = -ENOMEM;
> + goto exit;
> + }
> +
> + /* Allocate space in shared memory. 8 bytes aligned. */
> + pos = shared_mem->pos;
> + shared_mem->pos += round_up(io.length, 8u);
> + io.ele_addr = (u64)shared_mem->dma_addr + pos;
> +
> + if ((io.flags & SE_MU_IO_FLAGS_USE_SEC_MEM) &&
> + !(io.flags & SE_MU_IO_FLAGS_USE_SHORT_ADDR)) {
> + /*Add base address to get full address.*/
> + dev_err(dev_ctx->priv->dev,
> + "%s: Failed allocate SEC MEM memory\n",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + }
> +
> + memset(shared_mem->ptr + pos, 0, io.length);
> + if ((io.flags & SE_IO_BUF_FLAGS_IS_INPUT) ||
> + (io.flags & SE_IO_BUF_FLAGS_IS_IN_OUT)) {
> + /*
> + * buffer is input:
> + * copy data from user space to this allocated buffer.
> + */
> + if (copy_from_user(shared_mem->ptr + pos, io.user_buf,
> + io.length)) {
> + dev_err(dev_ctx->priv->dev,
> + "%s: Failed copy data to shared memory\n",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + }
> + }
> +
> + b_desc = kzalloc(sizeof(*b_desc), GFP_KERNEL);
> + if (!b_desc) {
> + err = -ENOMEM;
> + goto exit;
> + }
> +
> +copy:
> + /* Provide the EdgeLock Enclave address to user space only if success.*/
> + if (copy_to_user((u8 *)arg, &io, sizeof(io))) {
> + dev_err(dev_ctx->priv->dev,
> + "%s: Failed to copy iobuff setup to user\n",
> + dev_ctx->miscdev.name);
> + kfree(b_desc);
> + err = -EFAULT;
> + goto exit;
> + }
> +
> + if (b_desc) {
> + b_desc->shared_buf_ptr = shared_mem->ptr + pos;
> + b_desc->usr_buf_ptr = io.user_buf;
> + b_desc->size = io.length;
> +
> + if (io.flags & SE_IO_BUF_FLAGS_IS_INPUT) {
> + /*
> + * buffer is input:
> + * add an entry in the "pending input buffers" list so
> + * that copied data can be cleaned from shared memory
> + * later.
> + */
> + list_add_tail(&b_desc->link, &dev_ctx->pending_in);
> + } else {
> + /*
> + * buffer is output:
> + * add an entry in the "pending out buffers" list so data
> + * can be copied to user space when receiving Secure-Enclave
> + * response.
> + */
> + list_add_tail(&b_desc->link, &dev_ctx->pending_out);
> + }
> + }
> +
> +exit:
> + return err;
> +}
> +
> +/* IOCTL to provide SoC information */
> +static int se_ioctl_get_se_soc_info_handler(struct se_if_device_ctx *dev_ctx,
> + u64 arg)
> +{
> + struct imx_se_node_info_list *info_list;
> + struct se_ioctl_get_soc_info soc_info;
> + int err = -EINVAL;
> +
> + info_list = (struct imx_se_node_info_list *)
> + device_get_match_data(dev_ctx->priv->dev);
> + if (!info_list)
> + goto exit;
> +
> + soc_info.soc_id = info_list->soc_id;
> + soc_info.soc_rev = dev_ctx->priv->soc_rev;
> +
> + err = (int)copy_to_user((u8 *)arg, (u8 *)(&soc_info), sizeof(soc_info));
> + if (err) {
> + dev_err(dev_ctx->priv->dev,
> + "%s: Failed to copy soc info to user\n",
> + dev_ctx->miscdev.name);
> + err = -EFAULT;
> + goto exit;
> + }
> +
> +exit:
> + return err;
> +}
> +
> +/* Open a character device. */
> +static int se_if_fops_open(struct inode *nd, struct file *fp)
> +{
> + struct se_if_device_ctx *dev_ctx = container_of(fp->private_data,
> + struct se_if_device_ctx,
> + miscdev);
> + int err = 0;
> +
> + /* Avoid race if opened at the same time */
> + if (down_trylock(&dev_ctx->fops_lock))
> + return -EBUSY;
> +
> + /* Authorize only 1 instance. */
> + if (dev_ctx->status != SE_IF_CTX_FREE) {
> + err = -EBUSY;
> + goto exit;
> + }
> +
> + /*
> + * Allocate some memory for data exchanges with S40x.
> + * This will be used for data not requiring secure memory.
> + */
> + dev_ctx->non_secure_mem.ptr = dmam_alloc_coherent(dev_ctx->dev,
> + MAX_DATA_SIZE_PER_USER,
> + &dev_ctx->non_secure_mem.dma_addr,
> + GFP_KERNEL);
> + if (!dev_ctx->non_secure_mem.ptr) {
> + err = -ENOMEM;
> + goto exit;
> + }
> +
> + dev_ctx->non_secure_mem.size = MAX_DATA_SIZE_PER_USER;
> + dev_ctx->non_secure_mem.pos = 0;
> + dev_ctx->status = SE_IF_CTX_OPENED;
> +
> + dev_ctx->pending_hdr = 0;
> +
> + goto exit;
> +
> + dmam_free_coherent(dev_ctx->priv->dev, MAX_DATA_SIZE_PER_USER,
> + dev_ctx->non_secure_mem.ptr,
> + dev_ctx->non_secure_mem.dma_addr);
> +
> +exit:
> + up(&dev_ctx->fops_lock);
> + return err;
> +}
> +
> +/* Close a character device. */
> +static int se_if_fops_close(struct inode *nd, struct file *fp)
> +{
> + struct se_if_device_ctx *dev_ctx = container_of(fp->private_data,
> + struct se_if_device_ctx,
> + miscdev);
> + struct se_if_priv *priv = dev_ctx->priv;
> + struct se_buf_desc *b_desc;
> +
> + /* Avoid race if closed at the same time */
> + if (down_trylock(&dev_ctx->fops_lock))
> + return -EBUSY;
> +
> + /* The device context has not been opened */
> + if (dev_ctx->status != SE_IF_CTX_OPENED)
> + goto exit;
> +
> + /* check if this device was registered as command receiver. */
> + if (priv->cmd_receiver_dev == dev_ctx)
> + priv->cmd_receiver_dev = NULL;
> +
> + /* check if this device was registered as waiting response. */
> + if (priv->waiting_rsp_dev == dev_ctx) {
> + priv->waiting_rsp_dev = NULL;
> + mutex_unlock(&priv->se_if_cmd_lock);
> + }
> +
> + /* Unmap secure memory shared buffer. */
> + if (dev_ctx->secure_mem.ptr)
> + devm_iounmap(dev_ctx->dev, dev_ctx->secure_mem.ptr);
> +
> + dev_ctx->secure_mem.ptr = NULL;
> + dev_ctx->secure_mem.dma_addr = 0;
> + dev_ctx->secure_mem.size = 0;
> + dev_ctx->secure_mem.pos = 0;
> +
> + /* Free non-secure shared buffer. */
> + dmam_free_coherent(dev_ctx->priv->dev, MAX_DATA_SIZE_PER_USER,
> + dev_ctx->non_secure_mem.ptr,
> + dev_ctx->non_secure_mem.dma_addr);
> +
> + dev_ctx->non_secure_mem.ptr = NULL;
> + dev_ctx->non_secure_mem.dma_addr = 0;
> + dev_ctx->non_secure_mem.size = 0;
> + dev_ctx->non_secure_mem.pos = 0;
> +
> + while (!list_empty(&dev_ctx->pending_in) ||
> + !list_empty(&dev_ctx->pending_out)) {
> + if (!list_empty(&dev_ctx->pending_in))
> + b_desc = list_first_entry_or_null(&dev_ctx->pending_in,
> + struct se_buf_desc,
> + link);
> + else
> + b_desc = list_first_entry_or_null(&dev_ctx->pending_out,
> + struct se_buf_desc,
> + link);
> +
> + if (!b_desc)
> + continue;
> +
> + if (b_desc->shared_buf_ptr)
> + memset(b_desc->shared_buf_ptr, 0, b_desc->size);
> +
> + __list_del_entry(&b_desc->link);
> + kfree(b_desc);
> + }
> +
> + dev_ctx->status = SE_IF_CTX_FREE;
> +
> +exit:
> + up(&dev_ctx->fops_lock);
> + return 0;
> +}
> +
> +/* IOCTL entry point of a character device */
> +static long se_ioctl(struct file *fp, unsigned int cmd, unsigned long arg)
> +{
> + struct se_if_device_ctx *dev_ctx = container_of(fp->private_data,
> + struct se_if_device_ctx,
> + miscdev);
> + struct se_if_priv *se_if_priv = dev_ctx->priv;
> + int err = -EINVAL;
> +
> + /* Prevent race during change of device context */
> + if (down_interruptible(&dev_ctx->fops_lock))
> + return -EBUSY;
> +
> + switch (cmd) {
> + case SE_IOCTL_ENABLE_CMD_RCV:
> + if (!se_if_priv->cmd_receiver_dev) {
> + se_if_priv->cmd_receiver_dev = dev_ctx;
> + err = 0;
> + }
> + break;
> + case SE_IOCTL_GET_MU_INFO:
> + err = se_ioctl_get_mu_info(dev_ctx, arg);
> + break;
> + case SE_IOCTL_SETUP_IOBUF:
> + err = se_ioctl_setup_iobuf_handler(dev_ctx, arg);
> + break;
> + case SE_IOCTL_GET_SOC_INFO:
> + err = se_ioctl_get_se_soc_info_handler(dev_ctx, arg);
> + break;
> +
> + default:
> + err = -EINVAL;
> + dev_dbg(se_if_priv->dev,
> + "%s: IOCTL %.8x not supported\n",
> + dev_ctx->miscdev.name,
> + cmd);
> + }
> +
> + up(&dev_ctx->fops_lock);
> + return (long)err;
> +}
> +
> +/* Char driver setup */
> +static const struct file_operations se_if_fops = {
> + .open = se_if_fops_open,
> + .owner = THIS_MODULE,
> + .release = se_if_fops_close,
> + .unlocked_ioctl = se_ioctl,
> + .read = se_if_fops_read,
> + .write = se_if_fops_write,
> +};
> +
> +/* interface for managed res to unregister a character device */
> +static void if_misc_deregister(void *miscdevice)
> +{
> + misc_deregister(miscdevice);
> +}
> +
> /* interface for managed res to free a mailbox channel */
> static void if_mbox_free_channel(void *mbox_chan)
> {
> @@ -270,6 +855,7 @@ static int se_probe_if_cleanup(struct platform_device *pdev)
> struct device *dev = &pdev->dev;
> struct se_if_priv *priv;
> int ret = 0;
> + int i;
>
> priv = dev_get_drvdata(dev);
> if (!priv) {
> @@ -294,6 +880,17 @@ static int se_probe_if_cleanup(struct platform_device *pdev)
> priv->imem.buf = NULL;
> }
>
> + if (priv->ctxs) {
> + for (i = 0; i < priv->max_dev_ctx; i++) {
> + if (priv->ctxs[i]) {
> + devm_remove_action(dev,
> + if_misc_deregister,
> + &priv->ctxs[i]->miscdev);
> + misc_deregister(&priv->ctxs[i]->miscdev);
> + }
> + }
> + }
> +
> if (priv->flags & RESERVED_DMA_POOL) {
> of_reserved_mem_device_release(dev);
> priv->flags &= (~RESERVED_DMA_POOL);
> @@ -302,6 +899,84 @@ static int se_probe_if_cleanup(struct platform_device *pdev)
> return ret;
> }
>
> +static int init_device_context(struct device *dev)
> +{
> + const struct imx_se_node_info *info;
> + struct se_if_device_ctx *dev_ctx;
> + struct se_if_priv *priv;
> + u8 *devname;
> + int ret = 0;
> + int i;
> +
> + priv = dev_get_drvdata(dev);
> +
> + if (!priv) {
> + ret = -EINVAL;
> + dev_err(dev, "Invalid SE-MU Priv data");
> + return ret;
> + }
> + info = priv->info;
> +
> + priv->ctxs = devm_kzalloc(dev, sizeof(dev_ctx) * priv->max_dev_ctx,
> + GFP_KERNEL);
> +
> + if (!priv->ctxs) {
> + ret = -ENOMEM;
> + return ret;
> + }
> +
> + /* Create users */
> + for (i = 0; i < priv->max_dev_ctx; i++) {
> + dev_ctx = devm_kzalloc(dev, sizeof(*dev_ctx), GFP_KERNEL);
> + if (!dev_ctx) {
> + ret = -ENOMEM;
> + return ret;
> + }
> +
> + dev_ctx->dev = dev;
> + dev_ctx->status = SE_IF_CTX_FREE;
> + dev_ctx->priv = priv;
> +
> + priv->ctxs[i] = dev_ctx;
> +
> + /* Default value invalid for an header. */
> + init_waitqueue_head(&dev_ctx->wq);
> +
> + INIT_LIST_HEAD(&dev_ctx->pending_out);
> + INIT_LIST_HEAD(&dev_ctx->pending_in);
> + sema_init(&dev_ctx->fops_lock, 1);
> +
> + devname = devm_kasprintf(dev, GFP_KERNEL, "%s_ch%d",
> + info->se_name, i);
> + if (!devname) {
> + ret = -ENOMEM;
> + return ret;
> + }
> +
> + dev_ctx->miscdev.name = devname;
> + dev_ctx->miscdev.minor = MISC_DYNAMIC_MINOR;
> + dev_ctx->miscdev.fops = &se_if_fops;
> + dev_ctx->miscdev.parent = dev;
> + ret = misc_register(&dev_ctx->miscdev);
> + if (ret) {
> + dev_err(dev, "failed to register misc device %d\n",
> + ret);
> + return ret;
> + }
> +
> + ret = devm_add_action(dev, if_misc_deregister,
> + &dev_ctx->miscdev);
> + if (ret) {
> + dev_err(dev,
> + "failed[%d] to add action to the misc-dev\n",
> + ret);
> + return ret;
> + }
> + }
> +
> + return ret;
> +}
> +
> static void se_load_firmware(const struct firmware *fw, void *context)
> {
> struct se_if_priv *priv = (struct se_if_priv *) context;
> @@ -461,6 +1136,16 @@ static int se_if_probe(struct platform_device *pdev)
> }
> }
>
> + if (info->max_dev_ctx) {
> + ret = init_device_context(dev);
> + if (ret) {
> + dev_err(dev,
> + "Failed[0x%x] to create device contexts.\n",
> + ret);
> + goto exit;
> + }
> + }
> +
> dev_info(dev, "i.MX secure-enclave: %s interface to firmware, configured.\n",
> info->se_name);
> return devm_of_platform_populate(dev);
> @@ -502,6 +1187,10 @@ static int se_resume(struct device *dev)
> struct se_if_priv *priv = dev_get_drvdata(dev);
> const struct imx_se_node_info *info
> = priv->info;
> + int i;
> +
> + for (i = 0; i < priv->max_dev_ctx; i++)
> + wake_up_interruptible(&priv->ctxs[i]->wq);
>
> if (info && info->imem_mgmt)
> se_restore_imem_state(dev);
> diff --git a/drivers/firmware/imx/se_ctrl.h b/drivers/firmware/imx/se_ctrl.h
> index 7d4f439a6158..41d9cedb05d7 100644
> --- a/drivers/firmware/imx/se_ctrl.h
> +++ b/drivers/firmware/imx/se_ctrl.h
> @@ -13,15 +13,61 @@
> #define MAX_FW_LOAD_RETRIES 50
>
> #define RES_STATUS(x) FIELD_GET(0x000000ff, x)
> +#define MAX_DATA_SIZE_PER_USER (65 * 1024)
> #define MESSAGING_VERSION_6 0x6
> #define MESSAGING_VERSION_7 0x7
>
> +#define SE_MU_IO_FLAGS_USE_SEC_MEM (0x02u)
> +#define SE_MU_IO_FLAGS_USE_SHORT_ADDR (0x04u)
> +
> struct se_imem_buf {
> u8 *buf;
> phys_addr_t phyaddr;
> u32 size;
> };
>
> +struct se_buf_desc {
> + u8 *shared_buf_ptr;
> + u8 *usr_buf_ptr;
> + u32 size;
> + struct list_head link;
> +};
> +
> +/* Status of a char device */
> +enum se_if_dev_ctx_status_t {
> + SE_IF_CTX_FREE,
> + SE_IF_CTX_OPENED
> +};
> +
> +struct se_shared_mem {
> + dma_addr_t dma_addr;
> + u32 size;
> + u32 pos;
> + u8 *ptr;
> +};
> +
> +/* Private struct for each char device instance. */
> +struct se_if_device_ctx {
> + struct device *dev;
> + struct se_if_priv *priv;
> + struct miscdevice miscdev;
> +
> + enum se_if_dev_ctx_status_t status;
> + wait_queue_head_t wq;
> + struct semaphore fops_lock;
> +
> + u32 pending_hdr;
> + struct list_head pending_in;
> + struct list_head pending_out;
> +
> + struct se_shared_mem secure_mem;
> + struct se_shared_mem non_secure_mem;
> +
> + u32 *temp_resp;
> + u32 temp_resp_size;
> + struct notifier_block se_notify;
> +};
> +
> /* Header of the messages exchange with the EdgeLock Enclave */
> struct se_msg_hdr {
> u8 ver;
> diff --git a/include/uapi/linux/se_ioctl.h b/include/uapi/linux/se_ioctl.h
> new file mode 100644
> index 000000000000..f68a36e9da2c
> --- /dev/null
> +++ b/include/uapi/linux/se_ioctl.h
> @@ -0,0 +1,88 @@
> +/* SPDX-License-Identifier: (GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause*/
> +/*
> + * Copyright 2024 NXP
> + */
> +
> +#ifndef SE_IOCTL_H
> +#define SE_IOCTL_H
> +
> +/* IOCTL definitions. */
> +
> +struct se_ioctl_setup_iobuf {
> + u8 *user_buf;
> + u32 length;
> + u32 flags;
> + u64 ele_addr;
> +};
> +
> +struct se_ioctl_shared_mem_cfg {
> + u32 base_offset;
> + u32 size;
> +};
> +
> +struct se_ioctl_get_if_info {
> + u8 se_if_id;
> + u8 interrupt_idx;
> + u8 tz;
> + u8 did;
> + u8 cmd_tag;
> + u8 rsp_tag;
> + u8 success_tag;
> + u8 base_api_ver;
> + u8 fw_api_ver;
> +};
> +
> +struct se_ioctl_signed_message {
> + u8 *message;
> + u32 msg_size;
> + u32 error_code;
> +};
> +
> +struct se_ioctl_get_soc_info {
> + u16 soc_id;
> + u16 soc_rev;
> +};
> +
> +/* IO Buffer Flags */
> +#define SE_IO_BUF_FLAGS_IS_OUTPUT (0x00u)
> +#define SE_IO_BUF_FLAGS_IS_INPUT (0x01u)
> +#define SE_IO_BUF_FLAGS_USE_SEC_MEM (0x02u)
> +#define SE_IO_BUF_FLAGS_USE_SHORT_ADDR (0x04u)
> +#define SE_IO_BUF_FLAGS_IS_IN_OUT (0x10u)
> +
> +/* IOCTLS */
> +#define SE_IOCTL 0x0A /* like MISC_MAJOR. */
> +
> +/*
> + * ioctl to designated the current fd as logical-reciever.
> + * This is ioctl is send when the nvm-daemon, a slave to the
> + * firmware is started by the user.
> + */
> +#define SE_IOCTL_ENABLE_CMD_RCV _IO(SE_IOCTL, 0x01)
> +
> +/*
> + * ioctl to get the buffer allocated from the memory, which is shared
> + * between kernel and FW.
> + * Post allocation, the kernel tagged the allocated memory with:
> + * Output
> + * Input
> + * Input-Output
> + * Short address
> + * Secure-memory
> + */
> +#define SE_IOCTL_SETUP_IOBUF _IOWR(SE_IOCTL, 0x03, \
> + struct se_ioctl_setup_iobuf)
> +
> +/*
> + * ioctl to get the mu information, that is used to exchange message
> + * with FW, from user-spaced.
> + */
> +#define SE_IOCTL_GET_MU_INFO _IOR(SE_IOCTL, 0x04, \
> + struct se_ioctl_get_if_info)
> +/*
> + * ioctl to get SoC Info from user-space.
> + */
> +#define SE_IOCTL_GET_SOC_INFO _IOR(SE_IOCTL, 0x06, \
> + struct se_ioctl_get_soc_info)
> +
> +#endif
>
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