Johannes Stratmann / mbed-dev

added prescaler for 16 bit pwm in LPC1347 target

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targets/hal/TARGET_Freescale/TARGET_KSDK2_MCUS/TARGET_MCU_K64F/entropy_hardware_poll.c@144:ef7eb2e8f9f7, 2016-09-02 (annotated)

Committer:
<>
Date:
Fri Sep 02 15:07:44 2016 +0100
Revision:
144:ef7eb2e8f9f7
This updates the lib to the mbed lib v125

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 144:ef7eb2e8f9f7 1 /*
<> 144:ef7eb2e8f9f7 2 * Hardware entropy collector for the K64F, using Freescale's RNGA
<> 144:ef7eb2e8f9f7 3 *
<> 144:ef7eb2e8f9f7 4 * Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
<> 144:ef7eb2e8f9f7 5 * SPDX-License-Identifier: Apache-2.0
<> 144:ef7eb2e8f9f7 6 *
<> 144:ef7eb2e8f9f7 7 * Licensed under the Apache License, Version 2.0 (the "License"); you may
<> 144:ef7eb2e8f9f7 8 * not use this file except in compliance with the License.
<> 144:ef7eb2e8f9f7 9 * You may obtain a copy of the License at
<> 144:ef7eb2e8f9f7 10 *
<> 144:ef7eb2e8f9f7 11 * http://www.apache.org/licenses/LICENSE-2.0
<> 144:ef7eb2e8f9f7 12 *
<> 144:ef7eb2e8f9f7 13 * Unless required by applicable law or agreed to in writing, software
<> 144:ef7eb2e8f9f7 14 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
<> 144:ef7eb2e8f9f7 15 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 144:ef7eb2e8f9f7 16 * See the License for the specific language governing permissions and
<> 144:ef7eb2e8f9f7 17 * limitations under the License.
<> 144:ef7eb2e8f9f7 18 *
<> 144:ef7eb2e8f9f7 19 */
<> 144:ef7eb2e8f9f7 20
<> 144:ef7eb2e8f9f7 21 /*
<> 144:ef7eb2e8f9f7 22 * Reference: "K64 Sub-Family Reference Manual, Rev. 2", chapter 34
<> 144:ef7eb2e8f9f7 23 */
<> 144:ef7eb2e8f9f7 24
<> 144:ef7eb2e8f9f7 25 #include <stdlib.h>
<> 144:ef7eb2e8f9f7 26 #include "cmsis.h"
<> 144:ef7eb2e8f9f7 27 #include "fsl_common.h"
<> 144:ef7eb2e8f9f7 28 #include "fsl_clock.h"
<> 144:ef7eb2e8f9f7 29
<> 144:ef7eb2e8f9f7 30 /*
<> 144:ef7eb2e8f9f7 31 * Get one byte of entropy from the RNG, assuming it is up and running.
<> 144:ef7eb2e8f9f7 32 * As recommended (34.1.1), get only one bit of each output.
<> 144:ef7eb2e8f9f7 33 */
<> 144:ef7eb2e8f9f7 34 static void rng_get_byte( unsigned char *byte )
<> 144:ef7eb2e8f9f7 35 {
<> 144:ef7eb2e8f9f7 36 size_t bit;
<> 144:ef7eb2e8f9f7 37
<> 144:ef7eb2e8f9f7 38 /* 34.5 Steps 3-4-5: poll SR and read from OR when ready */
<> 144:ef7eb2e8f9f7 39 for( bit = 0; bit < 8; bit++ )
<> 144:ef7eb2e8f9f7 40 {
<> 144:ef7eb2e8f9f7 41 while( ( RNG->SR & RNG_SR_OREG_LVL_MASK ) == 0 );
<> 144:ef7eb2e8f9f7 42 *byte |= ( RNG->OR & 1 ) << bit;
<> 144:ef7eb2e8f9f7 43 }
<> 144:ef7eb2e8f9f7 44 }
<> 144:ef7eb2e8f9f7 45
<> 144:ef7eb2e8f9f7 46 /*
<> 144:ef7eb2e8f9f7 47 * Get len bytes of entropy from the hardware RNG.
<> 144:ef7eb2e8f9f7 48 */
<> 144:ef7eb2e8f9f7 49 int mbedtls_hardware_poll( void *data,
<> 144:ef7eb2e8f9f7 50 unsigned char *output, size_t len, size_t *olen )
<> 144:ef7eb2e8f9f7 51 {
<> 144:ef7eb2e8f9f7 52 size_t i;
<> 144:ef7eb2e8f9f7 53 int ret;
<> 144:ef7eb2e8f9f7 54 ((void) data);
<> 144:ef7eb2e8f9f7 55
<> 144:ef7eb2e8f9f7 56 CLOCK_EnableClock( kCLOCK_Rnga0 );
<> 144:ef7eb2e8f9f7 57 CLOCK_DisableClock( kCLOCK_Rnga0 );
<> 144:ef7eb2e8f9f7 58 CLOCK_EnableClock( kCLOCK_Rnga0 );
<> 144:ef7eb2e8f9f7 59
<> 144:ef7eb2e8f9f7 60 /* Set "Interrupt Mask", "High Assurance" and "Go",
<> 144:ef7eb2e8f9f7 61 * unset "Clear interrupt" and "Sleep" */
<> 144:ef7eb2e8f9f7 62 RNG->CR = RNG_CR_INTM_MASK | RNG_CR_HA_MASK | RNG_CR_GO_MASK;
<> 144:ef7eb2e8f9f7 63
<> 144:ef7eb2e8f9f7 64 for( i = 0; i < len; i++ )
<> 144:ef7eb2e8f9f7 65 rng_get_byte( output + i );
<> 144:ef7eb2e8f9f7 66
<> 144:ef7eb2e8f9f7 67 /* Just be extra sure that we didn't do it wrong */
<> 144:ef7eb2e8f9f7 68 if( ( RNG->SR & RNG_SR_SECV_MASK ) != 0 )
<> 144:ef7eb2e8f9f7 69 {
<> 144:ef7eb2e8f9f7 70 ret = -1;
<> 144:ef7eb2e8f9f7 71 goto cleanup;
<> 144:ef7eb2e8f9f7 72 }
<> 144:ef7eb2e8f9f7 73
<> 144:ef7eb2e8f9f7 74 *olen = len;
<> 144:ef7eb2e8f9f7 75 ret = 0;
<> 144:ef7eb2e8f9f7 76
<> 144:ef7eb2e8f9f7 77 cleanup:
<> 144:ef7eb2e8f9f7 78 /* Disable clock to save power - assume we're the only users of RNG */
<> 144:ef7eb2e8f9f7 79 CLOCK_DisableClock( kCLOCK_Rnga0 );
<> 144:ef7eb2e8f9f7 80
<> 144:ef7eb2e8f9f7 81 return( ret );
<> 144:ef7eb2e8f9f7 82 }
<> 144:ef7eb2e8f9f7 83