| /* |
| * Copyright (c) 2022, Arm Limited. All rights reserved. |
| * |
| * SPDX-License-Identifier: BSD-3-Clause |
| */ |
| |
| #include <assert.h> |
| #include <stddef.h> |
| #include <stdint.h> |
| #include <string.h> |
| |
| #include <drivers/arm/mhu.h> |
| |
| #include "mhu_v2_x.h" |
| |
| #define MHU_NOTIFY_VALUE (1234u) |
| |
| /* |
| * MHU devices for host: |
| * HSE: Host to Secure Enclave (sender device) |
| * SEH: Secure Enclave to Host (receiver device) |
| */ |
| struct mhu_v2_x_dev_t MHU1_HSE_DEV = {0, MHU_V2_X_SENDER_FRAME}; |
| struct mhu_v2_x_dev_t MHU1_SEH_DEV = {0, MHU_V2_X_RECEIVER_FRAME}; |
| |
| static enum mhu_error_t error_mapping_to_mhu_error_t(enum mhu_v2_x_error_t err) |
| { |
| switch (err) { |
| case MHU_V_2_X_ERR_NONE: |
| return MHU_ERR_NONE; |
| case MHU_V_2_X_ERR_NOT_INIT: |
| return MHU_ERR_NOT_INIT; |
| case MHU_V_2_X_ERR_ALREADY_INIT: |
| return MHU_ERR_ALREADY_INIT; |
| case MHU_V_2_X_ERR_UNSUPPORTED_VERSION: |
| return MHU_ERR_UNSUPPORTED_VERSION; |
| case MHU_V_2_X_ERR_INVALID_ARG: |
| return MHU_ERR_INVALID_ARG; |
| case MHU_V_2_X_ERR_GENERAL: |
| return MHU_ERR_GENERAL; |
| default: |
| return MHU_ERR_GENERAL; |
| } |
| } |
| |
| static enum mhu_v2_x_error_t signal_and_wait_for_clear(void) |
| { |
| enum mhu_v2_x_error_t err; |
| struct mhu_v2_x_dev_t *dev = &MHU1_HSE_DEV; |
| uint32_t val = MHU_NOTIFY_VALUE; |
| /* Using the last channel for notifications */ |
| uint32_t channel_notify = mhu_v2_x_get_num_channel_implemented(dev) - 1; |
| |
| err = mhu_v2_x_channel_send(dev, channel_notify, val); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return err; |
| } |
| |
| do { |
| err = mhu_v2_x_channel_poll(dev, channel_notify, &val); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| break; |
| } |
| } while (val != 0); |
| |
| return err; |
| } |
| |
| static enum mhu_v2_x_error_t wait_for_signal(void) |
| { |
| enum mhu_v2_x_error_t err; |
| struct mhu_v2_x_dev_t *dev = &MHU1_SEH_DEV; |
| uint32_t val = 0; |
| /* Using the last channel for notifications */ |
| uint32_t channel_notify = mhu_v2_x_get_num_channel_implemented(dev) - 1; |
| |
| do { |
| err = mhu_v2_x_channel_receive(dev, channel_notify, &val); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| break; |
| } |
| } while (val != MHU_NOTIFY_VALUE); |
| |
| return err; |
| } |
| |
| static enum mhu_v2_x_error_t clear_and_wait_for_next_signal(void) |
| { |
| enum mhu_v2_x_error_t err; |
| struct mhu_v2_x_dev_t *dev = &MHU1_SEH_DEV; |
| uint32_t num_channels = mhu_v2_x_get_num_channel_implemented(dev); |
| uint32_t i; |
| |
| /* Clear all channels */ |
| for (i = 0; i < num_channels; ++i) { |
| err = mhu_v2_x_channel_clear(dev, i); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return err; |
| } |
| } |
| |
| return wait_for_signal(); |
| } |
| |
| enum mhu_error_t mhu_init_sender(uintptr_t mhu_sender_base) |
| { |
| enum mhu_v2_x_error_t err; |
| |
| assert(mhu_sender_base != (uintptr_t)NULL); |
| |
| MHU1_HSE_DEV.base = mhu_sender_base; |
| |
| err = mhu_v2_x_driver_init(&MHU1_HSE_DEV, MHU_REV_READ_FROM_HW); |
| return error_mapping_to_mhu_error_t(err); |
| } |
| |
| enum mhu_error_t mhu_init_receiver(uintptr_t mhu_receiver_base) |
| { |
| enum mhu_v2_x_error_t err; |
| uint32_t num_channels, i; |
| |
| assert(mhu_receiver_base != (uintptr_t)NULL); |
| |
| MHU1_SEH_DEV.base = mhu_receiver_base; |
| |
| err = mhu_v2_x_driver_init(&MHU1_SEH_DEV, MHU_REV_READ_FROM_HW); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| |
| num_channels = mhu_v2_x_get_num_channel_implemented(&MHU1_SEH_DEV); |
| |
| /* Mask all channels except the notifying channel */ |
| for (i = 0; i < (num_channels - 1); ++i) { |
| err = mhu_v2_x_channel_mask_set(&MHU1_SEH_DEV, i, UINT32_MAX); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| } |
| |
| /* The last channel is used for notifications */ |
| err = mhu_v2_x_channel_mask_clear( |
| &MHU1_SEH_DEV, (num_channels - 1), UINT32_MAX); |
| return error_mapping_to_mhu_error_t(err); |
| } |
| |
| /* |
| * Public function. See mhu.h |
| * |
| * The basic steps of transferring a message: |
| * 1. Initiate MHU transfer. |
| * 2. Send over the size of the payload on Channel 1. It is the very first |
| * 4 Bytes of the transfer. Continue with Channel 2. |
| * 3. Send over the payload, writing the channels one after the other |
| * (4 Bytes each). The last available channel is reserved for controlling |
| * the transfer. |
| * When the last channel is reached or no more data is left, STOP. |
| * 4. Notify the receiver using the last channel and wait for acknowledge. |
| * If there is still data to transfer, jump to step 3. Otherwise, proceed. |
| * 5. Close MHU transfer. |
| * |
| */ |
| enum mhu_error_t mhu_send_data(const uint8_t *send_buffer, size_t size) |
| { |
| enum mhu_v2_x_error_t err; |
| struct mhu_v2_x_dev_t *dev = &MHU1_HSE_DEV; |
| uint32_t num_channels = mhu_v2_x_get_num_channel_implemented(dev); |
| uint32_t chan = 0; |
| uint32_t i; |
| uint32_t *p; |
| |
| /* For simplicity, require the send_buffer to be 4-byte aligned */ |
| if ((uintptr_t)send_buffer & 0x3U) { |
| return MHU_ERR_INVALID_ARG; |
| } |
| |
| err = mhu_v2_x_initiate_transfer(dev); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| |
| /* First send over the size of the actual message */ |
| err = mhu_v2_x_channel_send(dev, chan, (uint32_t)size); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| chan++; |
| |
| p = (uint32_t *)send_buffer; |
| for (i = 0; i < size; i += 4) { |
| err = mhu_v2_x_channel_send(dev, chan, *p++); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| if (++chan == (num_channels - 1)) { |
| err = signal_and_wait_for_clear(); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| chan = 0; |
| } |
| } |
| |
| /* Signal the end of transfer. |
| * It's not required to send a signal when the message was |
| * perfectly-aligned (num_channels - 1 channels were used in the last |
| * round) preventing it from signaling twice at the end of transfer. |
| */ |
| if (chan != 0) { |
| err = signal_and_wait_for_clear(); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| } |
| |
| err = mhu_v2_x_close_transfer(dev); |
| return error_mapping_to_mhu_error_t(err); |
| } |
| |
| /* |
| * Public function. See mhu.h |
| * |
| * The basic steps of receiving a message: |
| * 1. Read the size of the payload from Channel 1. It is the very first |
| * 4 Bytes of the transfer. Continue with Channel 2. |
| * 2. Receive the payload, read the channels one after the other |
| * (4 Bytes each). The last available channel is reserved for controlling |
| * the transfer. |
| * When the last channel is reached clear all the channels |
| * (also sending an acknowledge on the last channel). |
| * 3. If there is still data to receive wait for a notification on the last |
| * channel and jump to step 2 as soon as it arrived. Otherwise, proceed. |
| * 4. End of transfer. |
| * |
| */ |
| enum mhu_error_t mhu_receive_data(uint8_t *receive_buffer, size_t *size) |
| { |
| enum mhu_v2_x_error_t err; |
| struct mhu_v2_x_dev_t *dev = &MHU1_SEH_DEV; |
| uint32_t num_channels = mhu_v2_x_get_num_channel_implemented(dev); |
| uint32_t chan = 0; |
| uint32_t message_len; |
| uint32_t i; |
| uint32_t *p; |
| |
| /* For simplicity, require: |
| * - the receive_buffer to be 4-byte aligned, |
| * - the buffer size to be a multiple of 4. |
| */ |
| if (((uintptr_t)receive_buffer & 0x3U) || (*size & 0x3U)) { |
| return MHU_ERR_INVALID_ARG; |
| } |
| |
| /* Busy wait for incoming reply */ |
| err = wait_for_signal(); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| |
| /* The first word is the length of the actual message */ |
| err = mhu_v2_x_channel_receive(dev, chan, &message_len); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| chan++; |
| |
| if (message_len > *size) { |
| /* Message buffer too small */ |
| *size = message_len; |
| return MHU_ERR_BUFFER_TOO_SMALL; |
| } |
| |
| p = (uint32_t *)receive_buffer; |
| for (i = 0; i < message_len; i += 4) { |
| err = mhu_v2_x_channel_receive(dev, chan, p++); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| |
| /* Only wait for next transfer if there is still missing data */ |
| if (++chan == (num_channels - 1) && (message_len - i) > 4) { |
| /* Busy wait for next transfer */ |
| err = clear_and_wait_for_next_signal(); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| chan = 0; |
| } |
| } |
| |
| /* Clear all channels */ |
| for (i = 0; i < num_channels; ++i) { |
| err = mhu_v2_x_channel_clear(dev, i); |
| if (err != MHU_V_2_X_ERR_NONE) { |
| return error_mapping_to_mhu_error_t(err); |
| } |
| } |
| |
| *size = message_len; |
| |
| return MHU_ERR_NONE; |
| } |