From 3749426af1e900a1b3354922fdd7e8b3bfa38084 Mon Sep 17 00:00:00 2001 From: Keith Packard Date: Tue, 27 Jan 2015 17:18:42 -0800 Subject: [PATCH] altos/usbtrng-v2.0: Use stmf042 hardware CRC unit Switch from software to hardware for CRC computation. I think this must be faster, right? Signed-off-by: Keith Packard --- src/usbtrng-v2.0/Makefile | 1 + src/usbtrng-v2.0/ao_pins.h | 4 +++ src/usbtrng-v2.0/ao_usbtrng.c | 60 ++++++++--------------------------- 3 files changed, 18 insertions(+), 47 deletions(-) diff --git a/src/usbtrng-v2.0/Makefile b/src/usbtrng-v2.0/Makefile index 2806d377..abbdbbcc 100644 --- a/src/usbtrng-v2.0/Makefile +++ b/src/usbtrng-v2.0/Makefile @@ -24,6 +24,7 @@ ALTOS_SRC = \ ao_mutex.c \ ao_dma_stm.c \ ao_adc_fast.c \ + ao_crc_stm.c \ ao_stdio.c \ ao_led.c \ ao_romconfig.c \ diff --git a/src/usbtrng-v2.0/ao_pins.h b/src/usbtrng-v2.0/ao_pins.h index 90efb864..f22678be 100644 --- a/src/usbtrng-v2.0/ao_pins.h +++ b/src/usbtrng-v2.0/ao_pins.h @@ -55,4 +55,8 @@ #define AO_NUM_ADC 1 +/* CRC */ +#define AO_CRC_WIDTH 32 +#define AO_CRC_INIT 0xffffffff + #endif /* _AO_PINS_H_ */ diff --git a/src/usbtrng-v2.0/ao_usbtrng.c b/src/usbtrng-v2.0/ao_usbtrng.c index c5ed5603..26cfbac9 100644 --- a/src/usbtrng-v2.0/ao_usbtrng.c +++ b/src/usbtrng-v2.0/ao_usbtrng.c @@ -17,54 +17,19 @@ #include #include - -static const uint16_t crc16_table[256] = { - 0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241, - 0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440, - 0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40, - 0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841, - 0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40, - 0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41, - 0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641, - 0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040, - 0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240, - 0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441, - 0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41, - 0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840, - 0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41, - 0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40, - 0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640, - 0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041, - 0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240, - 0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441, - 0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41, - 0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840, - 0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41, - 0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40, - 0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640, - 0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041, - 0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241, - 0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440, - 0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40, - 0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841, - 0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40, - 0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41, - 0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641, - 0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040, -}; +#include static void ao_trng_fetch(void) { static uint16_t *buffer[2]; - static uint16_t adc_in[AO_USB_IN_SIZE]; /* twice as many as we need */ + static uint32_t adc_in[AO_USB_IN_SIZE/2]; /* twice as many as we need */ uint32_t kbytes = 1; uint32_t count; int usb_buf_id; - int i, j; - uint16_t crc16 = 0; + int i; uint16_t *buf; - uint8_t *rnd; + uint32_t *rnd; if (!buffer[0]) { buffer[0] = ao_usb_alloc(); @@ -80,16 +45,16 @@ ao_trng_fetch(void) ao_cmd_status = ao_cmd_success; usb_buf_id = 0; count = kbytes * (1024/AO_USB_IN_SIZE); + + ao_crc_reset(); + ao_led_on(AO_LED_GREEN); while (count--) { - ao_adc_read(adc_in, AO_USB_IN_SIZE); - rnd = (uint8_t *) adc_in; + ao_adc_read((uint16_t *) adc_in, AO_USB_IN_SIZE); + rnd = adc_in; buf = buffer[usb_buf_id]; - for (i = 0; i < 32; i++) { - for (j = 0; j < 4; j++) - crc16 = (crc16 >> 8) ^ crc16_table[(crc16 ^ *rnd++) & 0xff]; - *buf++ = crc16; - } + for (i = 0; i < 32; i++) + *buf++ = ao_crc_in_32_out_16(*rnd++); ao_led_toggle(AO_LED_GREEN|AO_LED_RED); ao_usb_write(buffer[usb_buf_id], AO_USB_IN_SIZE); ao_led_toggle(AO_LED_GREEN|AO_LED_RED); @@ -100,7 +65,7 @@ ao_trng_fetch(void) } static const struct ao_cmds usbtrng_cmds[] = { - { ao_trng_fetch, "f\0Fetch a block of numbers" }, + { ao_trng_fetch, "f \0Fetch a block of numbers" }, { 0, NULL }, }; @@ -113,6 +78,7 @@ void main(void) ao_timer_init(); ao_dma_init(); ao_adc_init(); + ao_crc_init(); ao_cmd_init(); -- 2.30.2