72 lines
1.5 KiB
C
72 lines
1.5 KiB
C
/*
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* Copyright (c) 2021 Telink Semiconductor
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*
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* SPDX-License-Identifier: Apache-2.0
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*/
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#define DT_DRV_COMPAT telink_b91_trng
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#include <trng.h>
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#include <drivers/entropy.h>
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#include <string.h>
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/* API implementation: driver initialization */
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static int entropy_b91_trng_init(const struct device *dev)
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{
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ARG_UNUSED(dev);
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trng_init();
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return 0;
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}
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/* API implementation: get_entropy */
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static int entropy_b91_trng_get_entropy(const struct device *dev,
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uint8_t *buffer, uint16_t length)
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{
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ARG_UNUSED(dev);
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uint32_t value = 0;
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while (length) {
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value = trng_rand();
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if (length >= sizeof(value)) {
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memcpy(buffer, &value, sizeof(value));
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buffer += sizeof(value);
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length -= sizeof(value);
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} else {
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memcpy(buffer, &value, length);
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break;
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}
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}
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return 0;
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}
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/* API implementation: get_entropy_isr */
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static int entropy_b91_trng_get_entropy_isr(const struct device *dev,
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uint8_t *buffer, uint16_t length,
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uint32_t flags)
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{
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ARG_UNUSED(flags);
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/* No specific handling in case of running from ISR, just call standard API */
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entropy_b91_trng_get_entropy(dev, buffer, length);
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return 0;
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}
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/* Entropy driver APIs structure */
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static const struct entropy_driver_api entropy_b91_trng_api = {
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.get_entropy = entropy_b91_trng_get_entropy,
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.get_entropy_isr = entropy_b91_trng_get_entropy_isr
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};
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/* Entropy driver registration */
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DEVICE_DT_INST_DEFINE(0, entropy_b91_trng_init,
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NULL, NULL, NULL,
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PRE_KERNEL_1, CONFIG_ENTROPY_INIT_PRIORITY,
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&entropy_b91_trng_api);
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