[EXT] Re: [PATCH v3 4/5] firmware: imx: add driver for NXP EdgeLock Enclave

Pankaj Gupta pankaj.gupta at nxp.com
Mon Jul 1 00:45:20 PDT 2024



> -----Original Message-----
> From: Sascha Hauer <s.hauer at pengutronix.de>
> Sent: Tuesday, June 18, 2024 2:02 PM
> To: Pankaj Gupta <pankaj.gupta at nxp.com>
> Cc: Jonathan Corbet <corbet at lwn.net>; Rob Herring <robh at kernel.org>;
> Krzysztof Kozlowski <krzk+dt at kernel.org>; Conor Dooley
> <conor+dt at kernel.org>; Shawn Guo <shawnguo at kernel.org>; Pengutronix
> Kernel Team <kernel at pengutronix.de>; Fabio Estevam <festevam at gmail.com>;
> Rob Herring <robh+dt at kernel.org>; Krzysztof Kozlowski
> <krzysztof.kozlowski+dt at linaro.org>; devicetree at vger.kernel.org;
> imx at lists.linux.dev; linux-kernel at vger.kernel.org; linux-arm-
> kernel at lists.infradead.org; linux-doc at vger.kernel.org
> Subject: [EXT] Re: [PATCH v3 4/5] firmware: imx: add driver for NXP EdgeLock
> Enclave
>
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>
> Hi Pankaj,
>
> Here's some review feedback. I think it'll take some more rounds to get this
> into shape.
>
> On Mon, Jun 17, 2024 at 12:59:42PM +0530, Pankaj Gupta wrote:
> > NXP hardware IP(s) for secure-enclaves like Edgelock Enclave(ELE), are
> > embedded in the SoC to support the features like HSM, SHE & V2X, using
> > message based communication interface.
> >
> > The secure enclave FW communicates on a dedicated messaging unit(MU)
> > based interface(s) with application core, where kernel is running.
> > It exists on specific i.MX processors. e.g. i.MX8ULP, i.MX93.
> >
> > This patch adds the driver for communication interface to
> > secure-enclave, for exchanging messages with NXP secure enclave HW
> > IP(s) like EdgeLock Enclave (ELE) from Kernel-space, used by kernel
> > management layers like
> > - DM-Crypt.
> >
> > Signed-off-by: Pankaj Gupta <pankaj.gupta at nxp.com>
> > ---
> >  drivers/firmware/imx/Kconfig        |  12 +
> >  drivers/firmware/imx/Makefile       |   2 +
> >  drivers/firmware/imx/ele_base_msg.c | 284 +++++++++++++++++++
> > drivers/firmware/imx/ele_base_msg.h |  90 ++++++
> >  drivers/firmware/imx/ele_common.c   | 233 ++++++++++++++++
> >  drivers/firmware/imx/ele_common.h   |  45 +++
> >  drivers/firmware/imx/se_ctrl.c      | 536
> ++++++++++++++++++++++++++++++++++++
> >  drivers/firmware/imx/se_ctrl.h      |  99 +++++++
> >  include/linux/firmware/imx/se_api.h |  14 +
> >  9 files changed, 1315 insertions(+)
> >
> > diff --git a/drivers/firmware/imx/Kconfig
> > b/drivers/firmware/imx/Kconfig index 183613f82a11..56bdca9bd917 100644
> > --- a/drivers/firmware/imx/Kconfig
> > +++ b/drivers/firmware/imx/Kconfig
> > @@ -22,3 +22,15 @@ config IMX_SCU
> >
> >         This driver manages the IPC interface between host CPU and the
> >         SCU firmware running on M4.
> > +
> > +config IMX_SEC_ENCLAVE
> > +     tristate "i.MX Embedded Secure Enclave - EdgeLock Enclave Firmware
> driver."
> > +     depends on IMX_MBOX && ARCH_MXC && ARM64
> > +     default m if ARCH_MXC
> > +
> > +     help
> > +       It is possible to use APIs exposed by the iMX Secure Enclave HW IP
> called:
> > +          - EdgeLock Enclave Firmware (for i.MX8ULP, i.MX93),
> > +          like base, HSM, V2X & SHE using the SAB protocol via the shared
> Messaging
> > +          Unit. This driver exposes these interfaces via a set of file descriptors
> > +          allowing to configure shared memory, send and receive messages.
> > diff --git a/drivers/firmware/imx/Makefile
> > b/drivers/firmware/imx/Makefile index 8f9f04a513a8..aa9033e0e9e3
> > 100644
> > --- a/drivers/firmware/imx/Makefile
> > +++ b/drivers/firmware/imx/Makefile
> > @@ -1,3 +1,5 @@
> >  # 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
> > +sec_enclave-objs             = se_ctrl.o ele_common.o ele_base_msg.o
> > +obj-${CONFIG_IMX_SEC_ENCLAVE}        += sec_enclave.o
> > diff --git a/drivers/firmware/imx/ele_base_msg.c
> > b/drivers/firmware/imx/ele_base_msg.c
> > new file mode 100644
> > index 000000000000..5bfd9c7e3f7e
> > --- /dev/null
> > +++ b/drivers/firmware/imx/ele_base_msg.c
> > @@ -0,0 +1,284 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright 2024 NXP
> > + */
> > +
> > +#include <linux/types.h>
> > +#include <linux/completion.h>
> > +#include <linux/dma-mapping.h>
> > +
> > +#include "ele_base_msg.h"
> > +#include "ele_common.h"
> > +
> > +int ele_get_info(struct device *dev, struct ele_dev_info *s_info) {
>
> I think all currently exported functions should take a struct se_if_priv
> * as context pointer.
> I can't find any place in which any of these functions is called differently than
> with priv->dev.

All the API(s) that construct a message to be exchanged over the device-interface to FW,
- will be the exported symbols in the next patch-set, to be used by other Linux kernel modules like: NVMEM driver, linux crypto framework, security/keys etc.
- These other Linux layers have to choose from multiple similar devices per secure-enclave.

Kindly Consider these API(s), to be the EXPORT SYMBOLS, in later patches, when used outside of this driver.
>
> > +     struct se_if_priv *priv = dev_get_drvdata(dev);
> > +     struct se_api_msg *tx_msg __free(kfree) = NULL;
> > +     struct se_api_msg *rx_msg __free(kfree) = NULL;
> > +     phys_addr_t get_info_addr = 0;
> > +     u32 *get_info_data = NULL;
> > +     u32 status;
> > +     int ret = 0;
> > +
> > +     memset(s_info, 0x0, sizeof(*s_info));
> > +
> > +     if (priv->mem_pool_name)
> > +             get_info_data = get_phy_buf_mem_pool(dev,
> > +                                                  priv->mem_pool_name,
> > +                                                  &get_info_addr,
> > +                                                  ELE_GET_INFO_BUFF_SZ);
> > +     else
> > +             get_info_data = dma_alloc_coherent(dev,
> > +                                                ELE_GET_INFO_BUFF_SZ,
> > +                                                &get_info_addr,
> > +                                                GFP_KERNEL);
> > +     if (!get_info_data) {
> > +             ret = -ENOMEM;
> > +             dev_dbg(dev,
> > +                     "%s: Failed to allocate get_info_addr.\n",
> > +                     __func__);
> > +             goto exit;
>
> Just return here and you can drop the if(get_info_data) in the exit path.
I think it is good to have single exit path.
Accepted.

>
> > +     }
> > +
> > +     tx_msg = kzalloc(ELE_GET_INFO_REQ_MSG_SZ, GFP_KERNEL);
> > +     if (!tx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     rx_msg = kzalloc(ELE_GET_INFO_RSP_MSG_SZ, GFP_KERNEL);
> > +     if (!rx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     ret = imx_se_fill_cmd_msg_hdr(priv,
> > +                                   (struct se_msg_hdr *)&tx_msg->header,
> > +                                   ELE_GET_INFO_REQ,
> > +                                   ELE_GET_INFO_REQ_MSG_SZ,
> > +                                   true);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     tx_msg->data[0] = upper_32_bits(get_info_addr);
> > +     tx_msg->data[1] = lower_32_bits(get_info_addr);
> > +     tx_msg->data[2] = sizeof(struct ele_dev_info);
>
> Use sizeof(*s_info). It will increase the chance of doing the right thing here on
> struct renames and such.
Accepted.

>
> > +     ret = imx_ele_msg_send_rcv(priv, tx_msg, rx_msg);
> > +     if (ret < 0)
> > +             goto exit;
> > +
> > +     ret = validate_rsp_hdr(priv,
> > +                            &priv->rx_msg->header,
> > +                            ELE_GET_INFO_REQ,
> > +                            ELE_GET_INFO_RSP_MSG_SZ,
> > +                            true);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     status = RES_STATUS(priv->rx_msg->data[0]);
> > +     if (status != priv->success_tag) {
> > +             dev_err(dev, "Command Id[%d], Response Failure = 0x%x",
> > +                     ELE_GET_INFO_REQ, status);
> > +             ret = -EPERM;
> > +     }
> > +
> > +     memcpy(s_info, get_info_data, sizeof(struct ele_dev_info));
> > +
> > +exit:
> > +     if (get_info_addr) {
> > +             if (priv->mem_pool_name)
> > +                     free_phybuf_mem_pool(dev, priv->mem_pool_name,
> > +                                          get_info_data, ELE_GET_INFO_BUFF_SZ);
> > +             else
> > +                     dma_free_coherent(dev,
> > +                                       ELE_GET_INFO_BUFF_SZ,
> > +                                       get_info_data,
> > +                                       get_info_addr);
> > +     }
> > +
> > +     return ret;
> > +}
> > +
> > +int ele_fetch_soc_info(struct device *dev, u16 *soc_rev, u64
> > +*serial_num) {
> > +     struct ele_dev_info s_info = {0};
> > +     int err = 0;
> > +
> > +     err = ele_get_info(dev, &s_info);
> > +     if (err < 0) {
> > +             dev_err(dev, "Error");
> > +             return err;
> > +     }
> > +
> > +     *soc_rev = s_info.d_info.soc_rev;
> > +     *serial_num = GET_SERIAL_NUM_FROM_UID(s_info.d_info.uid,
> > + MAX_UID_SIZE >> 2);
> > +
> > +     return err;
> > +}
> > +
> > +int ele_ping(struct device *dev)
> > +{
> > +     struct se_if_priv *priv = dev_get_drvdata(dev);
> > +     struct se_api_msg *tx_msg __free(kfree) = NULL;
> > +     struct se_api_msg *rx_msg __free(kfree) = NULL;
> > +     u32 status;
> > +     int ret = 0;
> > +
> > +     tx_msg = kzalloc(ELE_PING_REQ_SZ, GFP_KERNEL);
> > +     if (!tx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     rx_msg = kzalloc(ELE_PING_RSP_SZ, GFP_KERNEL);
> > +     if (!rx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     ret = imx_se_fill_cmd_msg_hdr(priv,
> > +                                   (struct se_msg_hdr *)&tx_msg->header,
> > +                                   ELE_PING_REQ, ELE_PING_REQ_SZ, true);
> > +     if (ret) {
> > +             dev_err(dev, "Error: imx_se_fill_cmd_msg_hdr failed.\n");
> > +             goto exit;
> > +     }
> > +
> > +     ret = imx_ele_msg_send_rcv(priv, tx_msg, rx_msg);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     ret = validate_rsp_hdr(priv,
> > +                            &priv->rx_msg->header,
> > +                            ELE_PING_REQ,
> > +                            ELE_PING_RSP_SZ,
> > +                            true);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     status = RES_STATUS(priv->rx_msg->data[0]);
> > +     if (status != priv->success_tag) {
> > +             dev_err(dev, "Command Id[%d], Response Failure = 0x%x",
> > +                     ELE_PING_REQ, status);
> > +             ret = -EPERM;
> > +     }
> > +exit:
> > +     return ret;
> > +}
> > +
> > +int ele_service_swap(struct device *dev,
> > +                  phys_addr_t addr,
> > +                  u32 addr_size, u16 flag) {
> > +     struct se_if_priv *priv = dev_get_drvdata(dev);
> > +     struct se_api_msg *tx_msg __free(kfree) = NULL;
> > +     struct se_api_msg *rx_msg __free(kfree) = NULL;
> > +     u32 status;
> > +     int ret = 0;
> > +
> > +     tx_msg = kzalloc(ELE_SERVICE_SWAP_REQ_MSG_SZ, GFP_KERNEL);
> > +     if (!tx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     rx_msg = kzalloc(ELE_SERVICE_SWAP_RSP_MSG_SZ, GFP_KERNEL);
> > +     if (!rx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     ret = imx_se_fill_cmd_msg_hdr(priv,
> > +                                   (struct se_msg_hdr *)&tx_msg->header,
> > +                                   ELE_SERVICE_SWAP_REQ,
> > +                                   ELE_SERVICE_SWAP_REQ_MSG_SZ, true);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     tx_msg->data[0] = flag;
> > +     tx_msg->data[1] = addr_size;
> > +     tx_msg->data[2] = ELE_NONE_VAL;
> > +     tx_msg->data[3] = lower_32_bits(addr);
> > +     tx_msg->data[4] = imx_se_add_msg_crc((uint32_t *)&tx_msg[0],
> > +                                              ELE_SERVICE_SWAP_REQ_MSG_SZ);
> > +     ret = imx_ele_msg_send_rcv(priv, tx_msg, rx_msg);
> > +     if (ret < 0)
> > +             goto exit;
> > +
> > +     ret = validate_rsp_hdr(priv,
> > +                            &priv->rx_msg->header,
> > +                            ELE_SERVICE_SWAP_REQ,
> > +                            ELE_SERVICE_SWAP_RSP_MSG_SZ,
> > +                            true);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     status = RES_STATUS(priv->rx_msg->data[0]);
> > +     if (status != priv->success_tag) {
> > +             dev_err(dev, "Command Id[%d], Response Failure = 0x%x",
> > +                     ELE_SERVICE_SWAP_REQ, status);
> > +             ret = -EPERM;
> > +     } else {
> > +             if (flag == ELE_IMEM_EXPORT)
> > +                     ret = priv->rx_msg->data[1];
> > +             else
> > +                     ret = 0;
> > +     }
> > +exit:
> > +
> > +     return ret;
> > +}
> > +
> > +int ele_fw_authenticate(struct device *dev, phys_addr_t addr) {
> > +     struct se_if_priv *priv = dev_get_drvdata(dev);
> > +     struct se_api_msg *tx_msg __free(kfree) = NULL;
> > +     struct se_api_msg *rx_msg __free(kfree) = NULL;
> > +     u32 status;
> > +     int ret = 0;
> > +
> > +     tx_msg = kzalloc(ELE_FW_AUTH_REQ_SZ, GFP_KERNEL);
> > +     if (!tx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     rx_msg = kzalloc(ELE_FW_AUTH_RSP_MSG_SZ, GFP_KERNEL);
> > +     if (!rx_msg) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +     ret = imx_se_fill_cmd_msg_hdr(priv,
> > +                                   (struct se_msg_hdr *)&tx_msg->header,
> > +                                   ELE_FW_AUTH_REQ,
> > +                                   ELE_FW_AUTH_REQ_SZ,
> > +                                   true);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     tx_msg->data[0] = addr;
> > +     tx_msg->data[1] = addr >> 32;
> > +     tx_msg->data[2] = addr;
>
> Use upper_32_bits() and lower_32_bits() as done elsewhere.

Accepted.


>
> > +
> > +     ret = imx_ele_msg_send_rcv(priv, tx_msg, rx_msg);
> > +     if (ret < 0)
> > +             goto exit;
> > +
> > +     ret = validate_rsp_hdr(priv,
> > +                            &priv->rx_msg->header,
> > +                            ELE_FW_AUTH_REQ,
> > +                            ELE_FW_AUTH_RSP_MSG_SZ,
> > +                            true);
>
> You should use rx_msg here instead of priv->rx_msg. First of all it makes the
> code clearer and also you take the mutex protecting
> priv->rx_msg only inside of imx_ele_msg_send_rcv() which means rx_msg
> priv->could have been set differently by a concurrent call
> already.
>
> Same applies to other places in this file.
Accepted.

>
> > +     if (ret)
> > +             goto exit;
> > +
> > +     status = RES_STATUS(priv->rx_msg->data[0]);
> > +     if (status != priv->success_tag) {
>
> Apart from priv->rx_msg (which you shouldn't use here) priv->success_tag is
> the only member of struct se_if_priv that you actually use in this file.
>
> You could add a imx_ele_message_status() function to ele_common.c and
> make struct se_if_priv opaque to this file.
Accepted.

Moved the status check to validate_rsp_hdr. Rename the function to "se_val_rsp_hdr_n_status"

>
>
> > +             dev_err(dev, "Command Id[%d], Response Failure = 0x%x",
> > +                     ELE_FW_AUTH_REQ, status);
> > +             ret = -EPERM;
> > +     }
> > +exit:
> > +
> > +     return ret;
> > +}
> > diff --git a/drivers/firmware/imx/ele_base_msg.h
> > b/drivers/firmware/imx/ele_base_msg.h
> > new file mode 100644
> > index 000000000000..7838fe883810
> > --- /dev/null
> > +++ b/drivers/firmware/imx/ele_base_msg.h
> > @@ -0,0 +1,90 @@
> > +/* SPDX-License-Identifier: GPL-2.0+ */
> > +/*
> > + * Copyright 2024 NXP
> > + *
> > + * Header file for the EdgeLock Enclave Base API(s).
> > + */
> > +
> > +#ifndef ELE_BASE_MSG_H
> > +#define ELE_BASE_MSG_H
> > +
> > +#include <linux/device.h>
> > +#include <linux/types.h>
> > +
> > +#define WORD_SZ                              4
> > +#define ELE_NONE_VAL                 0x0
> > +
> > +#define ELE_GET_INFO_REQ             0xDA
> > +#define ELE_GET_INFO_REQ_MSG_SZ              0x10
> > +#define ELE_GET_INFO_RSP_MSG_SZ              0x08
> > +
> > +#define ELE_GET_INFO_BUFF_SZ         0x100
> > +
> > +#define DEFAULT_IMX_SOC_VER          0xA000
> > +#define SOC_VER_MASK                 0xFFFF0000
> > +#define SOC_ID_MASK                  0x0000FFFF
> > +
> > +#define MAX_UID_SIZE                     (16)
> > +#define DEV_GETINFO_ROM_PATCH_SHA_SZ     (32)
> > +#define DEV_GETINFO_FW_SHA_SZ            (32)
> > +#define DEV_GETINFO_OEM_SRKH_SZ          (64)
> > +#define DEV_GETINFO_MIN_VER_MASK     0xFF
> > +#define DEV_GETINFO_MAJ_VER_MASK     0xFF00
> > +
> > +struct dev_info {
> > +     uint8_t  cmd;
> > +     uint8_t  ver;
> > +     uint16_t length;
> > +     uint16_t soc_id;
> > +     uint16_t soc_rev;
> > +     uint16_t lmda_val;
> > +     uint8_t  ssm_state;
> > +     uint8_t  dev_atts_api_ver;
> > +     uint8_t  uid[MAX_UID_SIZE];
> > +     uint8_t  sha_rom_patch[DEV_GETINFO_ROM_PATCH_SHA_SZ];
> > +     uint8_t  sha_fw[DEV_GETINFO_FW_SHA_SZ]; };
> > +
> > +struct dev_addn_info {
> > +     uint8_t  oem_srkh[DEV_GETINFO_OEM_SRKH_SZ];
> > +     uint8_t  trng_state;
> > +     uint8_t  csal_state;
> > +     uint8_t  imem_state;
> > +     uint8_t  reserved2;
> > +};
> > +
> > +struct ele_dev_info {
> > +     struct dev_info d_info;
> > +     struct dev_addn_info d_addn_info; };
> > +
> > +#define GET_SERIAL_NUM_FROM_UID(x, uid_word_sz) \
> > +     (((u64)(((u32 *)(x))[(uid_word_sz) - 1]) << 32) | ((u32
> > +*)(x))[0])
> > +
> > +#define ELE_PING_REQ                 0x01
> > +#define ELE_PING_REQ_SZ                      0x04
> > +#define ELE_PING_RSP_SZ                      0x08
> > +
> > +#define ELE_SERVICE_SWAP_REQ         0xDF
> > +#define ELE_SERVICE_SWAP_REQ_MSG_SZ  0x18 #define
> > +ELE_SERVICE_SWAP_RSP_MSG_SZ  0x0C
> > +#define ELE_IMEM_SIZE                        0x10000
> > +#define ELE_IMEM_STATE_OK            0xCA
> > +#define ELE_IMEM_STATE_BAD           0xFE
> > +#define ELE_IMEM_STATE_WORD          0x27
> > +#define ELE_IMEM_STATE_MASK          0x00ff0000
> > +#define ELE_IMEM_EXPORT                      0x1
> > +#define ELE_IMEM_IMPORT                      0x2
> > +
> > +#define ELE_FW_AUTH_REQ                      0x02
> > +#define ELE_FW_AUTH_REQ_SZ           0x10
> > +#define ELE_FW_AUTH_RSP_MSG_SZ               0x08
> > +
> > +int ele_get_info(struct device *dev, struct ele_dev_info *s_info);
> > +int ele_fetch_soc_info(struct device *dev, u16 *soc_rev, u64
> > +*serial_num); int ele_ping(struct device *dev); int
> > +ele_service_swap(struct device *dev,
> > +                  phys_addr_t addr,
> > +                  u32 addr_size, u16 flag); int
> > +ele_fw_authenticate(struct device *dev, phys_addr_t addr); #endif
> > diff --git a/drivers/firmware/imx/ele_common.c
> > b/drivers/firmware/imx/ele_common.c
> > new file mode 100644
> > index 000000000000..0139748f7150
> > --- /dev/null
> > +++ b/drivers/firmware/imx/ele_common.c
> > @@ -0,0 +1,233 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright 2024 NXP
> > + */
> > +
> > +#include "ele_base_msg.h"
> > +#include "ele_common.h"
> > +
> > +u32 imx_se_add_msg_crc(u32 *msg, u32 msg_len) {
> > +     u32 nb_words = msg_len / (u32)sizeof(u32);
> > +     u32 crc = 0;
> > +     u32 i;
> > +
> > +     for (i = 0; i < nb_words - 1; i++)
> > +             crc ^= *(msg + i);
> > +
> > +     return crc;
> > +}
> > +
> > +int imx_ele_msg_rcv(struct se_if_priv *priv) {
> > +     u32 wait;
> > +     int err = 0;
> > +
> > +     lockdep_assert_held(&priv->se_if_cmd_lock);
> > +
> > +     wait = msecs_to_jiffies(1000);
> > +     if (!wait_for_completion_timeout(&priv->done, wait)) {
> > +             dev_err(priv->dev,
> > +                             "Error: wait_for_completion timed out.\n");
> > +             err = -ETIMEDOUT;
> > +     }
> > +
> > +     return err;
> > +}
> > +
> > +int imx_ele_msg_send(struct se_if_priv *priv, void *tx_msg) {
> > +     struct se_msg_hdr *header;
> > +     int err;
> > +
> > +     header = (struct se_msg_hdr *) tx_msg;
>
> Unnecessary cast.

Accepted.

>
> > +
> > +     if (header->tag == priv->cmd_tag)
> > +             lockdep_assert_held(&priv->se_if_cmd_lock);
> > +
> > +     scoped_guard(mutex, &priv->se_if_lock);
> > +
> > +     err = mbox_send_message(priv->tx_chan, tx_msg);
> > +     if (err < 0) {
> > +             dev_err(priv->dev, "Error: mbox_send_message failure.\n");
> > +             return err;
> > +     }
> > +
> > +     return err;
> > +}
> > +
> > +/* API used for send/receive blocking call. */ int
> > +imx_ele_msg_send_rcv(struct se_if_priv *priv, void *tx_msg, void
> > +*rx_msg) {
> > +     int err;
> > +
> > +     scoped_guard(mutex, &priv->se_if_cmd_lock);
> > +     if (priv->waiting_rsp_dev) {
> > +             dev_warn(priv->dev,
> > +                     "There should be no misc dev-ctx, waiting for resp.\n");
> > +             priv->waiting_rsp_dev = NULL;
> > +     }
> > +     priv->rx_msg = rx_msg;
> > +     err = imx_ele_msg_send(priv, tx_msg);
> > +     if (err < 0)
> > +             goto exit;
> > +
> > +     err = imx_ele_msg_rcv(priv);
> > +
> > +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_priv *priv;
> > +     struct se_msg_hdr *header;
> > +
> > +     priv = dev_get_drvdata(dev);
> > +
> > +     /* The function can be called with NULL msg */
> > +     if (!msg) {
> > +             dev_err(dev, "Message is invalid\n");
>
> Is it really worth spamming the log with this? It doesn't seem to contain useful
> information.
Accepted. Will add meaningful message "Empty(NULL) message received from FW."

>
> > +             return;
> > +     }
> > +
> > +     header = (struct se_msg_hdr *) msg;
>
> No need to cast explicitly.

Accepted.

>
> > +
> > +     if (header->tag == priv->rsp_tag) {
> > +             if (!priv->waiting_rsp_dev) {
> > +                     /*
> > +                      * Reading the EdgeLock Enclave response
> > +                      * to the command, sent by other
> > +                      * linux kernel services.
> > +                      */
> > +                     spin_lock(&priv->lock);
> > +                     memcpy(priv->rx_msg, msg, header->size << 2);
>
> You should check that header->size << 2 fits into the rx_msg before doing this.
Accepted. Need to add the size of the buffer to priv structure.

>
> > +
> > +                     complete(&priv->done);
> > +                     spin_unlock(&priv->lock);
> > +                     return;
> > +             }
> > +     } else {
> > +             dev_err(dev, "Failed to select a device for message: %.8x\n",
> > +                             *((u32 *) header));
> > +             return;
> > +     }
> > +}
> > +
> > +int validate_rsp_hdr(struct se_if_priv *priv,
> > +                  struct se_msg_hdr *header,
> > +                  uint8_t msg_id,
> > +                  uint8_t sz,
> > +                  bool is_base_api)
> > +{
> > +     if (header->tag != priv->rsp_tag) {
> > +             dev_err(priv->dev,
> > +                     "MSG[0x%x] Hdr: Resp tag mismatch. (0x%x != 0x%x)",
> > +                     msg_id, header->tag, priv->rsp_tag);
> > +             return -EINVAL;
> > +     }
> > +
> > +     if (header->command != msg_id) {
> > +             dev_err(priv->dev,
> > +                     "MSG Header: Cmd id mismatch. (0x%x != 0x%x)",
> > +                     header->command, msg_id);
> > +             return -EINVAL;
> > +     }
> > +
> > +     if (header->size != (sz >> 2)) {
> > +             dev_err(priv->dev,
> > +                     "MSG[0x%x] Hdr: Cmd size mismatch. (0x%x != 0x%x)",
> > +                     msg_id, header->size, (sz >> 2));
> > +             return -EINVAL;
> > +     }
> > +
> > +     if (is_base_api && (header->ver != priv->base_api_ver)) {
> > +             dev_err(priv->dev,
> > +                     "MSG[0x%x] Hdr: Base API Vers mismatch. (0x%x != 0x%x)",
> > +                     msg_id, header->ver, priv->base_api_ver);
> > +             return -EINVAL;
> > +     } else if (!is_base_api && header->ver != priv->fw_api_ver) {
> > +             dev_err(priv->dev,
> > +                     "MSG[0x%x] Hdr: FW API Vers mismatch. (0x%x != 0x%x)",
> > +                     msg_id, header->ver, priv->fw_api_ver);
> > +             return -EINVAL;
> > +     }
> > +
> > +     return 0;
> > +}
> > +
> > +int se_save_imem_state(struct se_if_priv *priv) {
> > +     int ret;
> > +
> > +     /* EXPORT command will save encrypted IMEM to given address,
> > +      * so later in resume, IMEM can be restored from the given
> > +      * address.
> > +      *
> > +      * Size must be at least 64 kB.
> > +      */
> > +     ret = ele_service_swap(priv->dev,
> > +                            priv->imem.phyaddr,
> > +                            ELE_IMEM_SIZE,
> > +                            ELE_IMEM_EXPORT);
> > +     if (ret < 0)
> > +             dev_err(priv->dev, "Failed to export IMEM\n");
> > +     else
> > +             dev_info(priv->dev,
> > +                     "Exported %d bytes of encrypted IMEM\n",
> > +                     ret);
> > +
> > +     return ret;
> > +}
> > +
> > +int se_restore_imem_state(struct se_if_priv *priv) {
> > +     struct ele_dev_info s_info;
> > +     int ret;
> > +
> > +     /* get info from ELE */
> > +     ret = ele_get_info(priv->dev, &s_info);
> > +     if (ret) {
> > +             dev_err(priv->dev, "Failed to get info from ELE.\n");
> > +             return ret;
> > +     }
> > +
> > +     /* Get IMEM state, if 0xFE then import IMEM */
> > +     if (s_info.d_addn_info.imem_state == ELE_IMEM_STATE_BAD) {
> > +             /* IMPORT command will restore IMEM from the given
> > +              * address, here size is the actual size returned by ELE
> > +              * during the export operation
> > +              */
> > +             ret = ele_service_swap(priv->dev,
> > +                                    priv->imem.phyaddr,
> > +                                    priv->imem.size,
> > +                                    ELE_IMEM_IMPORT);
> > +             if (ret) {
> > +                     dev_err(priv->dev, "Failed to import IMEM\n");
> > +                     goto exit;
> > +             }
> > +     } else
> > +             goto exit;
> > +
> > +     /* After importing IMEM, check if IMEM state is equal to 0xCA
> > +      * to ensure IMEM is fully loaded and
> > +      * ELE functionality can be used.
> > +      */
> > +     ret = ele_get_info(priv->dev, &s_info);
> > +     if (ret) {
> > +             dev_err(priv->dev, "Failed to get info from ELE.\n");
> > +             goto exit;
> > +     }
> > +
> > +     if (s_info.d_addn_info.imem_state == ELE_IMEM_STATE_OK)
> > +             dev_info(priv->dev, "Successfully restored IMEM\n");
> > +     else
> > +             dev_err(priv->dev, "Failed to restore IMEM\n");
> > +
> > +exit:
> > +     return ret;
> > +}
> > diff --git a/drivers/firmware/imx/ele_common.h
> > b/drivers/firmware/imx/ele_common.h
> > new file mode 100644
> > index 000000000000..24569ad29a1f
> > --- /dev/null
> > +++ b/drivers/firmware/imx/ele_common.h
> > @@ -0,0 +1,45 @@
> > +/* SPDX-License-Identifier: GPL-2.0+ */
> > +/*
> > + * Copyright 2024 NXP
> > + */
> > +
> > +
> > +#ifndef __ELE_COMMON_H__
> > +#define __ELE_COMMON_H__
> > +
> > +#include "se_ctrl.h"
> > +
> > +#define ELE_SUCCESS_IND                      0xD6
> > +
> > +#define IMX_ELE_FW_DIR                 "imx/ele/"
> > +
> > +uint32_t imx_se_add_msg_crc(uint32_t *msg, uint32_t msg_len); 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); void
> > +se_if_rx_callback(struct mbox_client *mbox_cl, void *msg); int
> > +validate_rsp_hdr(struct se_if_priv *priv,
> > +                  struct se_msg_hdr *header,
> > +                  uint8_t msg_id,
> > +                  uint8_t sz,
> > +                  bool is_base_api);
> > +
> > +/* Fill a command message header with a given command ID and length
> > +in bytes. */ static inline int imx_se_fill_cmd_msg_hdr(struct se_if_priv *priv,
> > +                                       struct se_msg_hdr *hdr,
> > +                                       u8 cmd,
> > +                                       u32 len,
> > +                                       bool is_base_api) {
> > +     hdr->tag = priv->cmd_tag;
> > +     hdr->ver = (is_base_api) ? priv->base_api_ver : priv->fw_api_ver;
> > +     hdr->command = cmd;
> > +     hdr->size = len >> 2;
> > +
> > +     return 0;
> > +}
> > +
> > +int se_save_imem_state(struct se_if_priv *priv); int
> > +se_restore_imem_state(struct se_if_priv *priv);
>
> The function prefixes are still not consistent. We have imx_se_*, imx_ele_*,
> ele_* and se_*. Unless these are really different things please decide for one
> prefix.

API(s) Nomenclature guide:
- API specific to secure-enclave interface ( prefix used is se-if).
- agnostic to se-if. For such API(s):
        -- se_* are API(s) common for all SE(s) like: V2X, SHE, ELE.
              -- ele_* are API(s) common to ELE SE only.

Will convert the API name with prefix imx_ele_* or imx_se_*, to ele_* and se_*, respectively.

>
> > +
> > +#endif /*__ELE_COMMON_H__ */
> > diff --git a/drivers/firmware/imx/se_ctrl.c
> > b/drivers/firmware/imx/se_ctrl.c new file mode 100644 index
> > 000000000000..a7a7cacb4416
> > --- /dev/null
> > +++ b/drivers/firmware/imx/se_ctrl.c
> > @@ -0,0 +1,536 @@
> > +// SPDX-License-Identifier: GPL-2.0+
> > +/*
> > + * Copyright 2024 NXP
> > + */
> > +
> > +#include <linux/completion.h>
> > +#include <linux/delay.h>
> > +#include <linux/dev_printk.h>
> > +#include <linux/dma-mapping.h>
> > +#include <linux/errno.h>
> > +#include <linux/export.h>
> > +#include <linux/firmware.h>
> > +#include <linux/firmware/imx/se_api.h> #include <linux/genalloc.h>
> > +#include <linux/init.h> #include <linux/io.h> #include
> > +<linux/miscdevice.h> #include <linux/mod_devicetable.h> #include
> > +<linux/module.h> #include <linux/of_platform.h> #include
> > +<linux/of_reserved_mem.h> #include <linux/platform_device.h> #include
> > +<linux/slab.h> #include <linux/string.h> #include <linux/sys_soc.h>
> > +
> > +#include "ele_base_msg.h"
> > +#include "ele_common.h"
> > +#include "se_ctrl.h"
> > +
> > +#define RESERVED_DMA_POOL            BIT(0)
> > +
> > +struct imx_se_node_info {
> > +     u8 se_if_id;
> > +     u8 se_if_did;
> > +     u8 max_dev_ctx;
> > +     u8 cmd_tag;
> > +     u8 rsp_tag;
> > +     u8 success_tag;
> > +     u8 base_api_ver;
> > +     u8 fw_api_ver;
> > +     u8 *se_name;
> > +     u8 *mbox_tx_name;
> > +     u8 *mbox_rx_name;
> > +     u8 *pool_name;
> > +     u8 *fw_name_in_rfs;
> > +     bool soc_register;
> > +     bool reserved_dma_ranges;
> > +     bool imem_mgmt;
> > +     int (*se_fetch_soc_info)(struct device *dev, u16 *soc_rev, u64
> > +*serial_num); };
> > +
> > +struct imx_se_node_info_list {
> > +     u8 num_mu;
> > +     u16 soc_id;
> > +     struct imx_se_node_info info[];
> > +};
> > +
> > +static const struct imx_se_node_info_list imx8ulp_info = {
> > +     .num_mu = 1,
> > +     .soc_id = SOC_ID_OF_IMX8ULP,
> > +     .info = {
> > +                     {
> > +                     .se_if_id = 2,
> > +                     .se_if_did = 7,
> > +                     .max_dev_ctx = 4,
> > +                     .cmd_tag = 0x17,
> > +                     .rsp_tag = 0xe1,
> > +                     .success_tag = ELE_SUCCESS_IND,
> > +                     .base_api_ver = MESSAGING_VERSION_6,
> > +                     .fw_api_ver = MESSAGING_VERSION_7,
> > +                     .se_name = "hsm1",
> > +                     .mbox_tx_name = "tx",
> > +                     .mbox_rx_name = "rx",
> > +                     .pool_name = "sram",
> > +                     .fw_name_in_rfs = IMX_ELE_FW_DIR
> > +                                       "mx8ulpa2ext-ahab-container.img",
> > +                     .soc_register = true,
> > +                     .reserved_dma_ranges = true,
> > +                     .imem_mgmt = true,
> > +                     .se_fetch_soc_info = ele_fetch_soc_info,
> > +                     },
> > +     },
> > +};
> > +
> > +static const struct imx_se_node_info_list imx93_info = {
> > +     .num_mu = 1,
> > +     .soc_id = SOC_ID_OF_IMX93,
> > +     .info = {
> > +                     {
> > +                     .se_if_id = 2,
> > +                     .se_if_did = 3,
> > +                     .max_dev_ctx = 4,
> > +                     .cmd_tag = 0x17,
> > +                     .rsp_tag = 0xe1,
> > +                     .success_tag = ELE_SUCCESS_IND,
> > +                     .base_api_ver = MESSAGING_VERSION_6,
> > +                     .fw_api_ver = MESSAGING_VERSION_7,
> > +                     .se_name = "hsm1",
> > +                     .mbox_tx_name = "tx",
> > +                     .mbox_rx_name = "rx",
> > +                     .reserved_dma_ranges = true,
> > +                     .soc_register = true,
> > +                     },
> > +     },
> > +};
> > +
> > +static const struct of_device_id se_match[] = {
> > +     { .compatible = "fsl,imx8ulp-se", .data = (void *)&imx8ulp_info},
> > +     { .compatible = "fsl,imx93-se", .data = (void *)&imx93_info},
> > +     {},
> > +};
> > +
> > +static const struct imx_se_node_info
> > +     *get_imx_se_node_info(const struct imx_se_node_info_list *info_list,
> > +                           const u32 idx) {
> > +     if (idx > info_list->num_mu)
> > +             return NULL;
> > +
> > +     return &info_list->info[idx];
> > +}
> > +
> > +void *get_phy_buf_mem_pool(struct device *dev,
> > +                        u8 *mem_pool_name,
> > +                        dma_addr_t *buf,
> > +                        u32 size)
> > +{
> > +     struct device_node *of_node = dev->of_node;
> > +     struct gen_pool *mem_pool;
> > +
> > +     mem_pool = of_gen_pool_get(of_node, mem_pool_name, 0);
> > +     if (!mem_pool) {
> > +             dev_err(dev,
> > +                     "Unable to get sram pool = %s\n",
> > +                     mem_pool_name);
> > +             return 0;
> > +     }
> > +
> > +     return gen_pool_dma_alloc(mem_pool, size, buf); }
> > +
> > +void free_phybuf_mem_pool(struct device *dev,
> > +                       u8 *mem_pool_name,
> > +                       u32 *buf,
> > +                       u32 size)
>
> The function name is not consistent with the get_ function above (phybuf vs.
> phy_buf). Also a function prefix would be nice.
>
Accepted. Removed this function.

> > +{
> > +     struct device_node *of_node = dev->of_node;
> > +     struct gen_pool *mem_pool;
> > +
> > +     mem_pool = of_gen_pool_get(of_node, mem_pool_name, 0);
> > +     if (!mem_pool)
> > +             dev_err(dev,
> > +                     "%s: Failed: Unable to get sram pool.\n",
> > +                     __func__);
> > +
> > +     gen_pool_free(mem_pool, (u64)buf, size); }
> > +
> > +static int imx_fetch_se_soc_info(struct se_if_priv *priv,
> > +                              const struct imx_se_node_info_list
> > +*info_list) {
> > +     const struct imx_se_node_info *info;
> > +     struct soc_device_attribute *attr;
> > +     struct soc_device *sdev;
> > +     u64 serial_num;
> > +     u16 soc_rev;
> > +     int err = 0;
> > +
> > +     info = priv->info;
> > +
> > +     /* This function should be called once.
> > +      * Check if the soc_rev is zero to continue.
> > +      */
> > +     if (priv->soc_rev)
> > +             return err;
>
> Just return 0 here. It takes one step less to understand what this is about.
Replacing "err" with "ret", in better understanding.

>

> > +
> > +     if (info->se_fetch_soc_info) {
> > +             err = info->se_fetch_soc_info(priv->dev, &soc_rev, &serial_num);
> > +             if (err < 0) {
> > +                     dev_err(priv->dev, "Failed to fetch SoC Info.");
> > +                     return err;
> > +             }
> > +     } else {
> > +             dev_err(priv->dev, "Failed to fetch SoC revision.");
> > +             if (info->soc_register)
> > +                     dev_err(priv->dev, "Failed to do SoC registration.");
> > +             err = -EINVAL;
> > +             return err;
> > +     }
>
> i.MX93 doesn't have a info->se_fetch_soc_info. Does this mean it doesn't work
> on this SoC?
>
Yes.

> > +
> > +     priv->soc_rev = soc_rev;
> > +     if (!info->soc_register)
> > +             return 0;
> > +
> > +     attr = devm_kzalloc(priv->dev, sizeof(*attr), GFP_KERNEL);
> > +     if (!attr)
> > +             return -ENOMEM;
> > +
> > +     if (FIELD_GET(DEV_GETINFO_MIN_VER_MASK, soc_rev))
> > +             attr->revision = devm_kasprintf(priv->dev, GFP_KERNEL, "%x.%x",
> > +                                             FIELD_GET(DEV_GETINFO_MIN_VER_MASK,
> > +                                                       soc_rev),
> > +                                             FIELD_GET(DEV_GETINFO_MAJ_VER_MASK,
> > +                                                       soc_rev));
> > +     else
> > +             attr->revision = devm_kasprintf(priv->dev, GFP_KERNEL, "%x",
> > +                                             FIELD_GET(DEV_GETINFO_MAJ_VER_MASK,
> > +                                                       soc_rev));
> > +
> > +     switch (info_list->soc_id) {
> > +     case SOC_ID_OF_IMX8ULP:
> > +             attr->soc_id = devm_kasprintf(priv->dev, GFP_KERNEL,
> > +                                           "i.MX8ULP");
> > +             break;
> > +     case SOC_ID_OF_IMX93:
> > +             attr->soc_id = devm_kasprintf(priv->dev, GFP_KERNEL,
> > +                                           "i.MX93");
> > +             break;
> > +     }
> > +
> > +     err = of_property_read_string(of_root, "model",
> > +                                   &attr->machine);
> > +     if (err)
> > +             return -EINVAL;
> > +
> > +     attr->family = devm_kasprintf(priv->dev, GFP_KERNEL, "Freescale
> > + i.MX");
> > +
> > +     attr->serial_number
> > +             = devm_kasprintf(priv->dev, GFP_KERNEL, "%016llX",
> > + serial_num);
> > +
> > +     sdev = soc_device_register(attr);
> > +     if (IS_ERR(sdev))
> > +             return PTR_ERR(sdev);
> > +
> > +     return 0;
> > +}
> > +
> > +/* interface for managed res to free a mailbox channel */ static void
> > +if_mbox_free_channel(void *mbox_chan) {
> > +     mbox_free_channel(mbox_chan);
> > +}
> > +
> > +static int se_if_request_channel(struct device *dev,
> > +                              struct mbox_chan **chan,
> > +                              struct mbox_client *cl,
> > +                              const char *name) {
> > +     struct mbox_chan *t_chan;
> > +     int ret = 0;
> > +
> > +     t_chan = mbox_request_channel_byname(cl, name);
> > +     if (IS_ERR(t_chan)) {
> > +             ret = PTR_ERR(t_chan);
> > +             return dev_err_probe(dev, ret,
> > +                                  "Failed to request %s channel.", name);
> > +     }
> > +
> > +     ret = devm_add_action(dev, if_mbox_free_channel, t_chan);
> > +     if (ret) {
> > +             dev_err(dev, "failed to add devm removal of mbox %s\n", name);
> > +             goto exit;
> > +     }
> > +
> > +     *chan = t_chan;
> > +
> > +exit:
> > +     return ret;
> > +}
> > +
> > +static int se_probe_if_cleanup(struct platform_device *pdev) {
> > +     struct device *dev = &pdev->dev;
> > +     struct se_if_priv *priv;
> > +     int ret = 0;
> > +
> > +     priv = dev_get_drvdata(dev);
> > +
> > +     if (priv->tx_chan)
> > +             mbox_free_channel(priv->tx_chan);
> > +     if (priv->rx_chan)
> > +             mbox_free_channel(priv->rx_chan);
>
> In se_if_request_channel() you use devm_add_action() to free the mbox
> channels. With this you release them twice.
Accepted.
Though the checks will prevent from releasing the channel twice
Will remove this.

>
> > +
> > +     /* free the buffer in se remove, previously allocated
> > +      * in se probe to store encrypted IMEM
> > +      */
> > +     if (priv->imem.buf) {
> > +             dmam_free_coherent(dev,
> > +                                ELE_IMEM_SIZE,
> > +                                priv->imem.buf,
> > +                                priv->imem.phyaddr);
> > +             priv->imem.buf = NULL;
> > +     }
> > +
> > +     /* No need to check, if reserved memory is allocated
> > +      * before calling for its release. Or clearing the
> > +      * un-set bit.
> > +      */
> > +     of_reserved_mem_device_release(dev);
> > +     priv->flags &= (~RESERVED_DMA_POOL);
>
> priv->flags is only set but never checked. Remove.
Accepted. Will remove this flag.


>
> > +
> > +     return ret;
> > +}
>
> This function can't fail and I think it shouldn't be able to. Let it return void.
Accepted.

>
> > +
> > +static void se_load_firmware(const struct firmware *fw, void
> > +*context) {
> > +     struct se_if_priv *priv = (struct se_if_priv *) context;
> > +     const struct imx_se_node_info *info = priv->info;
> > +     const u8 *se_fw_name = info->fw_name_in_rfs;
> > +     phys_addr_t se_fw_phyaddr;
> > +     u8 *se_fw_buf;
> > +
> > +     if (!fw) {
> > +             if (priv->fw_fail > MAX_FW_LOAD_RETRIES)
> > +                     dev_dbg(priv->dev,
> > +                              "External FW not found, using ROM FW.\n");
> > +             else {
> > +                     /*add a bit delay to wait for firmware priv released */
> > +                     msleep(20);
> > +
> > +                     /* Load firmware one more time if timeout */
> > +                     request_firmware_nowait(THIS_MODULE,
> > +                                     FW_ACTION_UEVENT, info->fw_name_in_rfs,
> > +                                     priv->dev, GFP_KERNEL, priv,
> > +                                     se_load_firmware);
> > +                     priv->fw_fail++;
> > +                     dev_dbg(priv->dev, "Value of retries = 0x%x.\n",
> > +                             priv->fw_fail);
> > +             }
> > +
> > +             return;
> > +     }
> > +
> > +     /* allocate buffer to store the SE FW */
> > +     se_fw_buf = dma_alloc_coherent(priv->dev, fw->size,
> > +                                    &se_fw_phyaddr, GFP_KERNEL);
> > +     if (!se_fw_buf) {
> > +             dev_err(priv->dev, "Failed to alloc SE fw buffer memory\n");
> > +             goto exit;
> > +     }
> > +
> > +     memcpy(se_fw_buf, fw->data, fw->size);
> > +
> > +     if (ele_fw_authenticate(priv->dev, se_fw_phyaddr))
> > +             dev_err(priv->dev,
> > +                     "Failed to authenticate & load SE firmware %s.\n",
> > +                     se_fw_name);
> > +
> > +     dma_free_coherent(priv->dev,
> > +                        fw->size,
> > +                        se_fw_buf,
> > +                        se_fw_phyaddr);
> > +
> > +exit:
> > +     release_firmware(fw);
> > +}
> > +
> > +static int se_if_probe(struct platform_device *pdev) {
> > +     const struct imx_se_node_info_list *info_list;
> > +     const struct imx_se_node_info *info;
> > +     struct device *dev = &pdev->dev;
> > +     struct se_if_priv *priv;
> > +     u32 idx;
> > +     int ret;
> > +
> > +     if (of_property_read_u32(dev->of_node, "reg", &idx)) {
> > +             ret = -EINVAL;
> > +             goto exit;
> > +     }
> > +
> > +     info_list = device_get_match_data(dev);
> > +     info = get_imx_se_node_info(info_list, idx);
> > +     if (!info) {
> > +             ret = -EINVAL;
> > +             goto exit;
> > +     }
> > +
> > +     priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL);
> > +     if (!priv) {
> > +             ret = -ENOMEM;
> > +             goto exit;
> > +     }
> > +
> > +     dev_set_drvdata(dev, priv);
> > +
> > +     /* Mailbox client configuration */
> > +     priv->se_mb_cl.dev              = dev;
> > +     priv->se_mb_cl.tx_block         = false;
> > +     priv->se_mb_cl.knows_txdone     = true;
> > +     priv->se_mb_cl.rx_callback      = se_if_rx_callback;
> > +
> > +     ret = se_if_request_channel(dev, &priv->tx_chan,
> > +                     &priv->se_mb_cl, info->mbox_tx_name);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     ret = se_if_request_channel(dev, &priv->rx_chan,
> > +                     &priv->se_mb_cl, info->mbox_rx_name);
> > +     if (ret)
> > +             goto exit;
> > +
> > +     priv->dev = dev;
> > +     priv->info = info;
> > +
> > +     mutex_init(&priv->se_if_lock);
> > +     mutex_init(&priv->se_if_cmd_lock);
> > +
> > +     priv->cmd_receiver_dev = NULL;
> > +     priv->waiting_rsp_dev = NULL;
>
> These are NULL already.
For code readability, it is good to know when and with what value it is initialized.
It will help review the 'if' condition based on these structure member variable.
Will covert this information into comments.


>
> > +     priv->max_dev_ctx = info->max_dev_ctx;
> > +     priv->cmd_tag = info->cmd_tag;
> > +     priv->rsp_tag = info->rsp_tag;
> > +     priv->mem_pool_name = info->pool_name;
>
> Instead of storing the mem_pool_name in priv you should call
> of_gen_pool_get() directly here and store the returned mem_pool in priv.
> It safes you from device tree parsing during runtime and makes the runtime
> code simpler.

Accepted.
Will make the changes as part v3.
Will remove the functions definition & declaration for: free_phybuf_mem_pool() & get_phybuf_mem_pool()

>
> > +     priv->success_tag = info->success_tag;
> > +     priv->base_api_ver = info->base_api_ver;
> > +     priv->fw_api_ver = info->fw_api_ver;
> > +
> > +     init_completion(&priv->done);
> > +     spin_lock_init(&priv->lock);
> > +
> > +     if (info->reserved_dma_ranges) {
> > +             ret = of_reserved_mem_device_init(dev);
> > +             if (ret) {
> > +                     dev_err(dev,
> > +                             "failed to init reserved memory region %d\n",
> > +                             ret);
> > +                     goto exit;
> > +             }
> > +             priv->flags |= RESERVED_DMA_POOL;
> > +     }
> > +
> > +     ret = imx_fetch_se_soc_info(priv, info_list);
> > +     if (ret) {
> > +             dev_err(dev,
> > +                     "failed[%pe] to fetch SoC Info\n", ERR_PTR(ret));
> > +             goto exit;
> > +     }
> > +
> > +     if (info->imem_mgmt) {
> > +             /* allocate buffer where SE store encrypted IMEM */
> > +             priv->imem.buf = dmam_alloc_coherent(dev, ELE_IMEM_SIZE,
> > +                                                  &priv->imem.phyaddr,
> > +                                                  GFP_KERNEL);
> > +             if (!priv->imem.buf) {
> > +                     dev_err(dev,
> > +                             "dmam-alloc-failed: To store encr-IMEM.\n");
> > +                     ret = -ENOMEM;
> > +                     goto exit;
> > +             }
> > +     }
> > +
> > +     if (info->fw_name_in_rfs) {
> > +             ret = request_firmware_nowait(THIS_MODULE,
> > +                                           FW_ACTION_UEVENT,
> > +                                           info->fw_name_in_rfs,
> > +                                           dev, GFP_KERNEL, priv,
> > +                                           se_load_firmware);
> > +             if (ret)
> > +                     dev_warn(dev, "Failed to get firmware [%s].\n",
> > +                              info->fw_name_in_rfs);
> > +             ret = 0;
> > +     }
> > +
> > +     dev_info(dev, "i.MX secure-enclave: %s interface to firmware,
> configured.\n",
> > +              info->se_name);
> > +     return ret;
> > +
> > +exit:
> > +     /* if execution control reaches here, if probe fails.
> > +      * hence doing the cleanup
> > +      */
> > +     if (se_probe_if_cleanup(pdev))
> > +             dev_err(dev,
> > +                     "Failed to clean-up the child node probe.\n");
> > +
> > +     return ret;
> > +}
> > +
> > +static int se_remove(struct platform_device *pdev) {
> > +     if (se_probe_if_cleanup(pdev))
> > +             dev_err(&pdev->dev,
> > +                     "i.MX Secure Enclave is not cleanly
> > +un-probed.");
> > +
> > +     return 0;
> > +}
> > +
> > +static int se_suspend(struct device *dev) {
> > +     struct se_if_priv *priv = dev_get_drvdata(dev);
> > +     const struct imx_se_node_info *info = priv->info;
> > +     int ret = 0;
> > +
> > +     if (info && info->imem_mgmt) {
> > +             ret = se_save_imem_state(priv);
> > +             if (ret < 0)
> > +                     goto exit;
> > +             priv->imem.size = ret;
> > +     }
> > +exit:
> > +     return ret;
> > +}
> > +
> > +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;
> > +
> > +     if (info && info->imem_mgmt)
> > +             se_restore_imem_state(priv);
> > +
> > +     return 0;
> > +}
> > +
> > +static const struct dev_pm_ops se_pm = {
> > +     RUNTIME_PM_OPS(se_suspend, se_resume, NULL) };
> > +
> > +static struct platform_driver se_driver = {
> > +     .driver = {
> > +             .name = "fsl-se-fw",
> > +             .of_match_table = se_match,
> > +             .pm = &se_pm,
> > +     },
> > +     .probe = se_if_probe,
> > +     .remove = se_remove,
> > +};
> > +MODULE_DEVICE_TABLE(of, se_match);
> > +
> > +module_platform_driver(se_driver);
> > +
> > +MODULE_AUTHOR("Pankaj Gupta <pankaj.gupta at nxp.com>");
> > +MODULE_DESCRIPTION("iMX Secure Enclave Driver.");
> > +MODULE_LICENSE("GPL");
> > diff --git a/drivers/firmware/imx/se_ctrl.h
> > b/drivers/firmware/imx/se_ctrl.h new file mode 100644 index
> > 000000000000..7d4f439a6158
> > --- /dev/null
> > +++ b/drivers/firmware/imx/se_ctrl.h
> > @@ -0,0 +1,99 @@
> > +/* SPDX-License-Identifier: GPL-2.0+ */
> > +/*
> > + * Copyright 2024 NXP
> > + */
> > +
> > +#ifndef SE_MU_H
> > +#define SE_MU_H
> > +
> > +#include <linux/miscdevice.h>
> > +#include <linux/semaphore.h>
> > +#include <linux/mailbox_client.h>
> > +
> > +#define MAX_FW_LOAD_RETRIES          50
> > +
> > +#define RES_STATUS(x)                        FIELD_GET(0x000000ff, x)
> > +#define MESSAGING_VERSION_6          0x6
> > +#define MESSAGING_VERSION_7          0x7
> > +
> > +struct se_imem_buf {
> > +     u8 *buf;
> > +     phys_addr_t phyaddr;
> > +     u32 size;
> > +};
> > +
> > +/* Header of the messages exchange with the EdgeLock Enclave */
> > +struct se_msg_hdr {
> > +     u8 ver;
> > +     u8 size;
> > +     u8 command;
> > +     u8 tag;
> > +}  __packed;
> > +
> > +#define SE_MU_HDR_SZ 4
> > +
> > +struct se_api_msg {
> > +     struct se_msg_hdr header;
> > +     u32 data[];
> > +};
> > +
> > +struct se_if_priv {
> > +     struct se_if_device_ctx *cmd_receiver_dev;
> > +     /* Update to the waiting_rsp_dev, to be protected
> > +      * under se_if_lock.
> > +      */
> > +     struct se_if_device_ctx *waiting_rsp_dev;
> > +     /*
> > +      * prevent parallel access to the se interface registers
> > +      * e.g. a user trying to send a command while the other one is
> > +      * sending a response.
> > +      */
> > +     struct mutex se_if_lock;
> > +     /*
> > +      * prevent a command to be sent on the se interface while another one is
> > +      * still processing. (response to a command is allowed)
> > +      */
> > +     struct mutex se_if_cmd_lock;
> > +     struct device *dev;
> > +     u8 *mem_pool_name;
> > +     u8 cmd_tag;
> > +     u8 rsp_tag;
> > +     u8 success_tag;
> > +     u8 base_api_ver;
> > +     u8 fw_api_ver;
> > +     u32 fw_fail;
> > +     u16 soc_rev;
> > +     const void *info;
> > +
> > +     struct mbox_client se_mb_cl;
> > +     struct mbox_chan *tx_chan, *rx_chan;
> > +
> > +     /* Assignment of the rx_msg buffer to held till the
> > +      * received content as part callback function, is copied.
> > +      */
> > +     struct se_api_msg *rx_msg;
> > +     struct completion done;
> > +     spinlock_t lock;
> > +     /*
> > +      * Flag to retain the state of initialization done at
> > +      * the time of se-if probe.
> > +      */
> > +     uint32_t flags;
> > +     u8 max_dev_ctx;
> > +     struct se_if_device_ctx **ctxs;
> > +     struct se_imem_buf imem;
> > +};
> > +
> > +void *get_phy_buf_mem_pool(struct device *dev,
> > +                        u8 *mem_pool_name,
> > +                        dma_addr_t *buf,
> > +                        u32 size);
> > +phys_addr_t get_phy_buf_mem_pool1(struct device *dev,
> > +                              u8 *mem_pool_name,
> > +                              u32 **buf,
> > +                              u32 size);
>
> This function prototype is unused.

Will remove it in v4.

>
> Sascha
>
> --
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