/****************************************************************************** * Copyright (C) 2023 Maxim Integrated Products, Inc., All Rights Reserved. * * 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 MAXIM INTEGRATED 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. * * Except as contained in this notice, the name of Maxim Integrated * Products, Inc. shall not be used except as stated in the Maxim Integrated * Products, Inc. Branding Policy. * * The mere transfer of this software does not imply any licenses * of trade secrets, proprietary technology, copyrights, patents, * trademarks, maskwork rights, or any other form of intellectual * property whatsoever. Maxim Integrated Products, Inc. retains all * ownership rights. * ******************************************************************************/ #include <stdlib.h> #include <string.h> #include "mxc_sys.h" #include "mxc_device.h" #include "mxc_errors.h" #include "mxc_assert.h" #include "mxc_lock.h" #include "trng_regs.h" #include "trng.h" #include "trng_revb.h" /***** Global Variables *****/ static mxc_trng_complete_t MXC_TRNG_Callback; static uint32_t TRNG_count, TRNG_maxLength; static uint8_t *TRNG_data; /* ************************************************************************* */ /* Global Control/Configuration functions */ /* ************************************************************************* */ int MXC_TRNG_RevB_Init(void) { return E_NO_ERROR; } void MXC_TRNG_RevB_EnableInt(mxc_trng_revb_regs_t *trng) { trng->ctrl |= MXC_F_TRNG_REVB_CTRL_RND_IE; } void MXC_TRNG_RevB_DisableInt(mxc_trng_revb_regs_t *trng) { trng->ctrl &= ~MXC_F_TRNG_REVB_CTRL_RND_IE; } int MXC_TRNG_RevB_Shutdown(void) { return E_NO_ERROR; } void MXC_TRNG_RevB_Handler(mxc_trng_revb_regs_t *trng) { uint32_t temp; mxc_trng_complete_t cb; // if this is last block, disable interrupt before reading trng->data if (TRNG_maxLength <= TRNG_count + 4) { trng->ctrl &= ~MXC_F_TRNG_REVB_CTRL_RND_IE; } temp = trng->data; if ((TRNG_count + 3) < TRNG_maxLength) { memcpy(&(TRNG_data[TRNG_count]), (uint8_t *)(&temp), 4); TRNG_count += 4; } else { memcpy(&(TRNG_data[TRNG_count]), (uint8_t *)(&temp), TRNG_maxLength & 0x03); TRNG_count += (TRNG_maxLength & 0x03); } if (TRNG_maxLength == TRNG_count) { cb = MXC_TRNG_Callback; cb(0, 0); } } /* ************************************************************************* */ /* True Random Number Generator(TRNG) functions */ /* ************************************************************************* */ int MXC_TRNG_RevB_RandomInt(mxc_trng_revb_regs_t *trng) { while (!(trng->status & MXC_F_TRNG_REVB_STATUS_RDY)) {} return (int)trng->data; } int MXC_TRNG_RevB_Random(uint8_t *data, uint32_t len) { unsigned int i, temp; if (data == NULL) { return E_NULL_PTR; } for (i = 0; (i + 3) < len; i += 4) { temp = MXC_TRNG_RandomInt(); memcpy(&(data[i]), (uint8_t *)(&temp), 4); } if (len & 0x03) { temp = MXC_TRNG_RandomInt(); memcpy(&(data[i]), (uint8_t *)(&temp), len & 0x03); } return E_NO_ERROR; } void MXC_TRNG_RevB_RandomAsync(mxc_trng_revb_regs_t *trng, uint8_t *data, uint32_t len, mxc_trng_complete_t callback) { MXC_ASSERT(data && callback); if (len == 0) { return; } TRNG_data = data; TRNG_count = 0; TRNG_maxLength = len; MXC_TRNG_Callback = callback; // Enable interrupts trng->ctrl |= MXC_F_TRNG_REVB_CTRL_RND_IE; } void MXC_TRNG_RevB_GenerateKey(mxc_trng_revb_regs_t *trng) { // Generate AES Key trng->ctrl |= MXC_F_TRNG_REVB_CTRL_AESKG_USR; // Wait for key transfer to complete while (trng->status & MXC_F_TRNG_REVB_STATUS_AESKGD) {}; } int MXC_TRNG_RevB_HealthTest(mxc_trng_revb_regs_t *trng) { /* Clear on-going test if necessary */ if (trng->ctrl & MXC_F_TRNG_REVB_CTRL_ODHT) { trng->ctrl &= ~MXC_F_TRNG_REVB_CTRL_ODHT; while (trng->status & MXC_F_TRNG_REVB_STATUS_ODHT) {} } /* Start on-demand health test */ trng->ctrl |= MXC_F_TRNG_REVB_CTRL_ODHT; /* Wait for test to finish */ while (trng->status & MXC_F_TRNG_REVB_STATUS_ODHT) {} /* Check results of test */ if (trng->status & MXC_F_TRNG_REVB_STATUS_HT) { return E_BAD_STATE; } return E_NO_ERROR; }