1 // Copyright 2021 Espressif Systems (Shanghai) PTE LTD 2 // 3 // Licensed under the Apache License, Version 2.0 (the "License"); 4 // you may not use this file except in compliance with the License. 5 // You may obtain a copy of the License at 6 // 7 // http://www.apache.org/licenses/LICENSE-2.0 8 // 9 // Unless required by applicable law or agreed to in writing, software 10 // distributed under the License is distributed on an "AS IS" BASIS, 11 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 // See the License for the specific language governing permissions and 13 // limitations under the License. 14 15 #pragma once 16 17 #include "soc/lldesc.h" 18 #include "esp_private/gdma.h" 19 #include "esp_err.h" 20 21 #ifdef __cplusplus 22 extern "C" { 23 #endif 24 25 /** 26 * @brief Start a GDMA transfer on the shared crypto DMA channel 27 * 28 * @note Will allocate a GDMA channel for AES & SHA if no such channel is already allocated 29 * 30 * @param input Input linked list descriptor 31 * @param output Output linked list descriptor 32 * @param peripheral Crypto peripheral to connect the DMA to, either GDMA_TRIG_PERIPH_AES or 33 * GDMA_TRIG_PERIPH_SHA 34 * @return esp_err_t ESP_FAIL if no GDMA channel available 35 */ 36 esp_err_t esp_crypto_shared_gdma_start(const lldesc_t *input, const lldesc_t *output, gdma_trigger_peripheral_t peripheral); 37 38 39 /** 40 * @brief Frees any shared crypto DMA channel, if esp_crypto_shared_gdma_start is called after 41 * this, new GDMA channels will be allocated. 42 * 43 * @note Function is meant to be called from user code, and thus takes AES/SHA lock. 44 * This means this function should not be called from code which already takes these locks, 45 * i.e. inside our AES/SHA code. 46 * 47 * If you are continously using AES/SHA (e.g. because of a wifi connection) then it's not recommended 48 * to use this API. Freeing the channel is mainly for use cases where you are finished with the crypto peripherals 49 * and need the DMA channel for other peripherals. An example would be doing some processing after disconnecting WiFi 50 */ 51 void esp_crypto_shared_gdma_free(void); 52 53 #ifdef __cplusplus 54 } 55 #endif 56
