From: Keith Packard <keithp@keithp.com>
Date: Tue, 27 Jan 2015 06:16:18 +0000 (-0800)
Subject: altos/usbtrng-v2.0: Add random output command
X-Git-Tag: 1.6~58
X-Git-Url: https://git.gag.com/?p=fw%2Faltos;a=commitdiff_plain;h=ac1a58af4d281a9bc3572dc503982a94e439a4c1

altos/usbtrng-v2.0: Add random output command

Read chunks of random ADC data, do some CRC16 computations to de-bias
and merge 4 bytes of input data into 2 bytes of output data, then dump
that out over USB.

Signed-off-by: Keith Packard <keithp@keithp.com>
---

diff --git a/src/usbtrng-v2.0/Makefile b/src/usbtrng-v2.0/Makefile
index 0d237630..2806d377 100644
--- a/src/usbtrng-v2.0/Makefile
+++ b/src/usbtrng-v2.0/Makefile
@@ -21,6 +21,9 @@ ALTOS_SRC = \
 	ao_interrupt.c \
 	ao_timer.c \
 	ao_panic.c \
+	ao_mutex.c \
+	ao_dma_stm.c \
+	ao_adc_fast.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 b84a88e9..90efb864 100644
--- a/src/usbtrng-v2.0/ao_pins.h
+++ b/src/usbtrng-v2.0/ao_pins.h
@@ -41,7 +41,18 @@
 #define AO_RCC_CFGR_PPRE_DIV	STM_RCC_CFGR_PPRE_DIV_1
 
 #define HAS_USB		1
+#define AO_USB_DIRECTIO	1
 
 #define IS_FLASH_LOADER	0
 
+/* ADC */
+
+#define AO_ADC_PIN0_PORT	(&stm_gpioa)
+#define AO_ADC_PIN0_PIN		6
+#define AO_ADC_PIN0_CH		6
+
+#define AO_ADC_RCC_AHBENR	((1 << STM_RCC_AHBENR_IOPAEN))
+
+#define AO_NUM_ADC		1
+
 #endif /* _AO_PINS_H_ */
diff --git a/src/usbtrng-v2.0/ao_usbtrng.c b/src/usbtrng-v2.0/ao_usbtrng.c
index 9b6fd4f1..c5ed5603 100644
--- a/src/usbtrng-v2.0/ao_usbtrng.c
+++ b/src/usbtrng-v2.0/ao_usbtrng.c
@@ -16,16 +16,93 @@
  */
 
 #include <ao.h>
+#include <ao_adc_fast.h>
 
-static void ao_blink(void)
+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,
+};
+
+static void
+ao_trng_fetch(void)
 {
-	for (;;) {
-		ao_led_toggle(LEDS_AVAILABLE);
-		ao_delay(AO_MS_TO_TICKS(500));
+	static uint16_t	*buffer[2];
+	static uint16_t	adc_in[AO_USB_IN_SIZE];	/* twice as many as we need */
+	uint32_t	kbytes = 1;
+	uint32_t	count;
+	int		usb_buf_id;
+	int		i, j;
+	uint16_t	crc16 = 0;
+	uint16_t	*buf;
+	uint8_t		*rnd;
+
+	if (!buffer[0]) {
+		buffer[0] = ao_usb_alloc();
+		buffer[1] = ao_usb_alloc();
+		if (!buffer[0])
+			return;
+	}
+
+	ao_cmd_decimal();
+	if (ao_cmd_status == ao_cmd_success)
+		kbytes = ao_cmd_lex_u32;
+	else
+		ao_cmd_status = ao_cmd_success;
+	usb_buf_id = 0;
+	count = kbytes * (1024/AO_USB_IN_SIZE);
+	ao_led_on(AO_LED_GREEN);
+	while (count--) {
+		ao_adc_read(adc_in, AO_USB_IN_SIZE);
+		rnd = (uint8_t *) 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;
+		}
+		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);
+		usb_buf_id = 1-usb_buf_id;
 	}
+	ao_led_off(AO_LED_GREEN|AO_LED_RED);
+	ao_usb_flush();
 }
 
-struct ao_task	blink_task;
+static const struct ao_cmds usbtrng_cmds[] = {
+	{ ao_trng_fetch,	"f\0Fetch a block of numbers" },
+	{ 0, NULL },
+};
 
 void main(void)
 {
@@ -34,12 +111,15 @@ void main(void)
 	ao_clock_init();
 	ao_task_init();
 	ao_timer_init();
+	ao_dma_init();
+	ao_adc_init();
 
 	ao_cmd_init();
 
 	ao_usb_init();
 
-	ao_add_task(&blink_task, ao_blink, "blink");
+	ao_cmd_register(usbtrng_cmds);
+	ao_led_off(AO_LED_RED);
 
 	ao_start_scheduler();
 }