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Diffstat (limited to 'nuttx/arch/arm/src/stm32/stm32_rng.c')
-rw-r--r--nuttx/arch/arm/src/stm32/stm32_rng.c264
1 files changed, 0 insertions, 264 deletions
diff --git a/nuttx/arch/arm/src/stm32/stm32_rng.c b/nuttx/arch/arm/src/stm32/stm32_rng.c
deleted file mode 100644
index 38e8108fe..000000000
--- a/nuttx/arch/arm/src/stm32/stm32_rng.c
+++ /dev/null
@@ -1,264 +0,0 @@
-/****************************************************************************
- * arch/arm/src/stm32/stm32_rng.c
- *
- * Copyright (C) 2012 Max Holtzberg. All rights reserved.
- * Author: Max Holtzberg <mh@uvc.de>
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *
- * 1. Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in
- * the documentation and/or other materials provided with the
- * distribution.
- * 3. Neither the name NuttX nor the names of its contributors may be
- * used to endorse or promote products derived from this software
- * without specific prior written permission.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
- * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
- * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
- * POSSIBILITY OF SUCH DAMAGE.
- *
- ****************************************************************************/
-
-/****************************************************************************
- * Included Files
- ****************************************************************************/
-
-#include <stdint.h>
-#include <stdio.h>
-#include <stdbool.h>
-#include <debug.h>
-#include <errno.h>
-
-#include <nuttx/irq.h>
-#include <nuttx/arch.h>
-
-#include "up_arch.h"
-#include "chip/stm32_rng.h"
-#include "up_internal.h"
-
-/****************************************************************************
- * Private Function Prototypes
- ****************************************************************************/
-
-static int stm32_rnginitialize(void);
-static int stm32_interrupt(int irq, void *context);
-static void stm32_enable(void);
-static void stm32_disable(void);
-static ssize_t stm32_read(struct file *filep, char *buffer, size_t);
-
-/****************************************************************************
- * Private Types
- ****************************************************************************/
-
-struct rng_dev_s
-{
- sem_t rd_devsem; /* Threads can only exclusively access the RNG */
- sem_t rd_readsem; /* To block until the buffer is filled */
- char *rd_buf;
- size_t rd_buflen;
- uint32_t rd_lastval;
- bool rd_first;
-};
-
-/****************************************************************************
- * Private Data
- ****************************************************************************/
-
-static struct rng_dev_s g_rngdev;
-
-static const struct file_operations g_rngops =
-{
- 0, /* open */
- 0, /* close */
- stm32_read, /* read */
- 0, /* write */
- 0, /* seek */
- 0 /* ioctl */
-#ifndef CONFIG_DISABLE_POLL
- ,0 /* poll */
-#endif
-};
-
-/****************************************************************************
- * Private functions
- ****************************************************************************/
-
-static int stm32_rnginitialize()
-{
- uint32_t regval;
-
- vdbg("Initializing RNG\n");
-
- memset(&g_rngdev, 0, sizeof(struct rng_dev_s));
-
- sem_init(&g_rngdev.rd_devsem, 0, 1);
-
- if (irq_attach(STM32_IRQ_RNG, stm32_interrupt))
- {
- /* We could not attach the ISR to the interrupt */
-
- vdbg("Could not attach IRQ.\n");
-
- return -EAGAIN;
- }
-
- /* Enable interrupts */
-
- regval = getreg32(STM32_RNG_CR);
- regval |= RNG_CR_IE;
- putreg32(regval, STM32_RNG_CR);
-
- up_enable_irq(STM32_IRQ_RNG);
-
- return OK;
-}
-
-static void stm32_enable()
-{
- uint32_t regval;
-
- g_rngdev.rd_first = true;
-
- regval = getreg32(STM32_RNG_CR);
- regval |= RNG_CR_RNGEN;
- putreg32(regval, STM32_RNG_CR);
-}
-
-static void stm32_disable()
-{
- uint32_t regval;
- regval = getreg32(STM32_RNG_CR);
- regval &= ~RNG_CR_RNGEN;
- putreg32(regval, STM32_RNG_CR);
-}
-
-static int stm32_interrupt(int irq, void *context)
-{
- uint32_t rngsr;
- uint32_t data;
-
- rngsr = getreg32(STM32_RNG_SR);
-
- if ((rngsr & (RNG_SR_SEIS | RNG_SR_CEIS)) /* Check for error bits */
- || !(rngsr & RNG_SR_DRDY)) /* Data ready must be set */
- {
- /* This random value is not valid, we will try again. */
-
- return OK;
- }
-
- data = getreg32(STM32_RNG_DR);
-
- /* As required by the FIPS PUB (Federal Information Processing Standard
- * Publication) 140-2, the first random number generated after setting the
- * RNGEN bit should not be used, but saved for comparison with the next
- * generated random number. Each subsequent generated random number has to be
- * compared with the previously generated number. The test fails if any two
- * compared numbers are equal (continuous random number generator test).
- */
-
- if (g_rngdev.rd_first)
- {
- g_rngdev.rd_first = false;
- g_rngdev.rd_lastval = data;
- return OK;
- }
-
- if (g_rngdev.rd_lastval == data)
- {
- /* Two subsequent same numbers, we will try again. */
-
- return OK;
- }
-
- /* If we get here, the random number is valid. */
-
- g_rngdev.rd_lastval = data;
-
- if (g_rngdev.rd_buflen >= 4)
- {
- g_rngdev.rd_buflen -= 4;
- *(uint32_t*)&g_rngdev.rd_buf[g_rngdev.rd_buflen] = data;
- }
- else
- {
- while (g_rngdev.rd_buflen > 0)
- {
- g_rngdev.rd_buf[--g_rngdev.rd_buflen] = (char)data;
- data >>= 8;
- }
- }
-
- if (g_rngdev.rd_buflen == 0)
- {
- /* Buffer filled, stop further interrupts. */
-
- stm32_disable();
- sem_post(&g_rngdev.rd_readsem);
- }
-
- return OK;
-}
-
-/****************************************************************************
- * Name: stm32_read
- ****************************************************************************/
-
-static ssize_t stm32_read(struct file *filep, char *buffer, size_t buflen)
-{
- if (sem_wait(&g_rngdev.rd_devsem) != OK)
- {
- return -errno;
- }
- else
- {
- /* We've got the semaphore. */
-
- /* Initialize semaphore with 0 for blocking until the buffer is filled from
- * interrupts.
- */
-
- sem_init(&g_rngdev.rd_readsem, 0, 1);
-
- g_rngdev.rd_buflen = buflen;
- g_rngdev.rd_buf = buffer;
-
- /* Enable RNG with interrupts */
-
- stm32_enable();
-
- /* Wait until the buffer is filled */
-
- sem_wait(&g_rngdev.rd_readsem);
-
- /* Free RNG for next use */
-
- sem_post(&g_rngdev.rd_devsem);
-
- return buflen;
- }
-}
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-void up_rnginitialize()
-{
- stm32_rnginitialize();
- register_driver("/dev/random", &g_rngops, 0444, NULL);
-}
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