root/sys/dev/pci/drm/amd/amdgpu/amdgpu_securedisplay.c
/*
 * Copyright 2021 Advanced Micro Devices, Inc.
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 *
 *
 */
#include <linux/debugfs.h>
#include <linux/pm_runtime.h>

#include "amdgpu.h"
#include "amdgpu_securedisplay.h"

/**
 * DOC: AMDGPU SECUREDISPLAY debugfs test interface
 *
 * how to use?
 * echo opcode <value> > <debugfs_dir>/dri/xxx/securedisplay_test
 * eg. echo 1 > <debugfs_dir>/dri/xxx/securedisplay_test
 * eg. echo 2 phy_id > <debugfs_dir>/dri/xxx/securedisplay_test
 *
 * opcode:
 * 1:Query whether TA is responding used only for validation pupose
 * 2: Send region of Interest and CRC value to I2C. (uint32)phy_id is
 * send to determine which DIO scratch register should be used to get
 * ROI and receive i2c_buf as the output.
 *
 * You can refer more detail from header file ta_securedisplay_if.h
 *
 */

void psp_securedisplay_parse_resp_status(struct psp_context *psp,
        enum ta_securedisplay_status status)
{
        switch (status) {
        case TA_SECUREDISPLAY_STATUS__SUCCESS:
                break;
        case TA_SECUREDISPLAY_STATUS__GENERIC_FAILURE:
                dev_err(psp->adev->dev, "Secure display: Generic Failure.");
                break;
        case TA_SECUREDISPLAY_STATUS__INVALID_PARAMETER:
                dev_err(psp->adev->dev, "Secure display: Invalid Parameter.");
                break;
        case TA_SECUREDISPLAY_STATUS__NULL_POINTER:
                dev_err(psp->adev->dev, "Secure display: Null Pointer.");
                break;
        case TA_SECUREDISPLAY_STATUS__I2C_WRITE_ERROR:
                dev_err(psp->adev->dev, "Secure display: Failed to write to I2C.");
                break;
        case TA_SECUREDISPLAY_STATUS__READ_DIO_SCRATCH_ERROR:
                dev_err(psp->adev->dev, "Secure display: Failed to Read DIO Scratch Register.");
                break;
        case TA_SECUREDISPLAY_STATUS__READ_CRC_ERROR:
                dev_err(psp->adev->dev, "Secure display: Failed to Read CRC");
                break;
        case TA_SECUREDISPLAY_STATUS__I2C_INIT_ERROR:
                dev_err(psp->adev->dev, "Secure display: Failed to initialize I2C.");
                break;
        default:
                dev_err(psp->adev->dev, "Secure display: Failed to parse status: %d\n", status);
        }
}

void psp_prep_securedisplay_cmd_buf(struct psp_context *psp, struct ta_securedisplay_cmd **cmd,
        enum ta_securedisplay_command command_id)
{
        *cmd = (struct ta_securedisplay_cmd *)psp->securedisplay_context.context.mem_context.shared_buf;
        memset(*cmd, 0, sizeof(struct ta_securedisplay_cmd));
        (*cmd)->status = TA_SECUREDISPLAY_STATUS__GENERIC_FAILURE;
        (*cmd)->cmd_id = command_id;
}

#if defined(CONFIG_DEBUG_FS)

static ssize_t amdgpu_securedisplay_debugfs_write(struct file *f, const char __user *buf,
                size_t size, loff_t *pos)
{
        struct amdgpu_device *adev = (struct amdgpu_device *)file_inode(f)->i_private;
        struct psp_context *psp = &adev->psp;
        struct ta_securedisplay_cmd *securedisplay_cmd;
        struct drm_device *dev = adev_to_drm(adev);
        uint32_t phy_id;
        uint32_t op;
        char str[64];
        int ret;

        if (*pos || size > sizeof(str) - 1)
                return -EINVAL;

        memset(str,  0, sizeof(str));
        ret = copy_from_user(str, buf, size);
        if (ret)
                return -EFAULT;

        ret = pm_runtime_get_sync(dev->dev);
        if (ret < 0) {
                pm_runtime_put_autosuspend(dev->dev);
                return ret;
        }

        if (size < 3)
                sscanf(str, "%u ", &op);
        else
                sscanf(str, "%u %u", &op, &phy_id);

        switch (op) {
        case 1:
                mutex_lock(&psp->securedisplay_context.mutex);
                psp_prep_securedisplay_cmd_buf(psp, &securedisplay_cmd,
                        TA_SECUREDISPLAY_COMMAND__QUERY_TA);
                ret = psp_securedisplay_invoke(psp, TA_SECUREDISPLAY_COMMAND__QUERY_TA);
                if (!ret) {
                        if (securedisplay_cmd->status == TA_SECUREDISPLAY_STATUS__SUCCESS)
                                dev_info(adev->dev, "SECUREDISPLAY: query securedisplay TA ret is 0x%X\n",
                                        securedisplay_cmd->securedisplay_out_message.query_ta.query_cmd_ret);
                        else
                                psp_securedisplay_parse_resp_status(psp, securedisplay_cmd->status);
                }
                mutex_unlock(&psp->securedisplay_context.mutex);
                break;
        case 2:
                if (size < 3 || phy_id >= TA_SECUREDISPLAY_MAX_PHY) {
                        dev_err(adev->dev, "Invalid input: %s\n", str);
                        return -EINVAL;
                }
                mutex_lock(&psp->securedisplay_context.mutex);
                psp_prep_securedisplay_cmd_buf(psp, &securedisplay_cmd,
                        TA_SECUREDISPLAY_COMMAND__SEND_ROI_CRC);
                securedisplay_cmd->securedisplay_in_message.send_roi_crc.phy_id = phy_id;
                ret = psp_securedisplay_invoke(psp, TA_SECUREDISPLAY_COMMAND__SEND_ROI_CRC);
                if (!ret) {
                        if (securedisplay_cmd->status == TA_SECUREDISPLAY_STATUS__SUCCESS) {
                                dev_info(adev->dev, "SECUREDISPLAY: I2C buffer out put is: %*ph\n",
                                         TA_SECUREDISPLAY_I2C_BUFFER_SIZE,
                                         securedisplay_cmd->securedisplay_out_message.send_roi_crc.i2c_buf);
                        } else {
                                psp_securedisplay_parse_resp_status(psp, securedisplay_cmd->status);
                        }
                }
                mutex_unlock(&psp->securedisplay_context.mutex);
                break;
        default:
                dev_err(adev->dev, "Invalid input: %s\n", str);
        }

        pm_runtime_mark_last_busy(dev->dev);
        pm_runtime_put_autosuspend(dev->dev);

        return size;
}

static const struct file_operations amdgpu_securedisplay_debugfs_ops = {
        .owner = THIS_MODULE,
        .read = NULL,
        .write = amdgpu_securedisplay_debugfs_write,
        .llseek = default_llseek
};

#endif

void amdgpu_securedisplay_debugfs_init(struct amdgpu_device *adev)
{
#if defined(CONFIG_DEBUG_FS)

        if (!adev->psp.securedisplay_context.context.initialized)
                return;

        debugfs_create_file("securedisplay_test", S_IWUSR, adev_to_drm(adev)->primary->debugfs_root,
                                adev, &amdgpu_securedisplay_debugfs_ops);
#endif
}