-/*
- * Copyright © 2014 Keith Packard <keithp@keithp.com>
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful, but
- * WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
- * General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
- */
-
-#include <ao.h>
-
-#define AO_TRNG_SPI_BUS 1
-
-static uint32_t spi_speed = AO_SPI_SPEED_4MHz;
-
-#define AO_TRNG_SPI_BUF 1024
-
-#if 0
-
-static uint8_t *spi_buf;
-static uint8_t *spi_head, *spi_tail;
-static uint8_t spi_wakeup;
-
-static void
-ao_trng_run(void)
-{
- int this_time;
- uint8_t *end;
-
- if (!spi_buf)
- spi_buf = ao_usb_alloc(AO_TRNG_SPI_BUF);
- flush();
- ao_spi_get(AO_TRNG_SPI_BUS, spi_speed);
- spi_tail = spi_buf;
- spi_head = spi_buf;
- ao_spi_recv_ring_start(spi_buf, AO_TRNG_SPI_BUF, &spi_head, &spi_tail, &spi_wakeup, AO_TRNG_SPI_BUS);
- while (!ao_usb_out_avail) {
- ao_arch_block_interrupts();
- while (spi_head == spi_tail) {
- spi_wakeup = 0;
- ao_sleep(&spi_wakeup);
- }
- ao_arch_release_interrupts();
- if (spi_tail > spi_head)
- end = spi_buf + AO_TRNG_SPI_BUF;
- else
- end = spi_head;
- this_time = end - spi_tail;
- if (this_time > 64)
- this_time = 64;
- ao_usb_write(spi_tail, this_time);
- spi_tail += this_time;
- if (spi_tail == spi_buf + AO_TRNG_SPI_BUF)
- spi_tail = spi_buf;
- }
- ao_spi_put(AO_TRNG_SPI_BUS);
- getchar();
-}
-
-
-static void
-ao_trng_test(void)
-{
- static uint8_t random[32];
- uint8_t i;
-
- ao_spi_get(AO_TRNG_SPI_BUS, spi_speed);
- ao_spi_recv(random, sizeof (random), AO_TRNG_SPI_BUS);
- ao_spi_put(AO_TRNG_SPI_BUS);
- for (i = 0; i < sizeof (random); i++)
- printf (" %02x", random[i]);
- printf ("\n");
-}
-#endif
-
-#define ADC_RING_SIZE 512
-
-static uint8_t *adc_ring;
-static uint16_t adc_head, adc_tail;
-static uint16_t adc_wake;
-
-void lpc_adc_isr(void)
-{
- uint16_t avail;
- uint16_t this, next;
-
- this = adc_head;
- next = (this + 1) & (ADC_RING_SIZE - 1);
- if (next == adc_tail) {
- lpc_adc.inten = 0;
- return;
- }
- adc_ring[this] = lpc_adc.dr[6] >> 8;
- adc_head = next;
-
- /* If there are enough entries, wake up any waiters
- */
- avail = (next - adc_tail) & (ADC_RING_SIZE - 1);
- if (avail >= adc_wake) {
- adc_wake = 0;
- ao_wakeup(&adc_wake);
- }
-}
-
-#define AO_ADC_CLKDIV (AO_LPC_SYSCLK / 450000)
-
-static void
-ao_trng_adc_init(void)
-{
- adc_ring = ao_usb_alloc(ADC_RING_SIZE);
-
- lpc_scb.sysahbclkctrl |= (1 << LPC_SCB_SYSAHBCLKCTRL_ADC);
- lpc_scb.pdruncfg &= ~(1 << LPC_SCB_PDRUNCFG_ADC_PD);
-
- /* Enable interrupt when AO_ADC_6 is complete */
- lpc_adc.inten = 0;
-
- lpc_nvic_set_enable(LPC_ISR_ADC_POS);
- lpc_nvic_set_priority(LPC_ISR_ADC_POS, AO_LPC_NVIC_CLOCK_PRIORITY);
-
-#if AO_ADC_0
- ao_enable_analog(0, 11, 0);
-#endif
-#if AO_ADC_1
- ao_enable_analog(0, 12, 1);
-#endif
-#if AO_ADC_2
- ao_enable_analog(0, 13, 2);
-#endif
-#if AO_ADC_3
- ao_enable_analog(0, 14, 3);
-#endif
-#if AO_ADC_4
- ao_enable_analog(0, 15, 4);
-#endif
-#if AO_ADC_5
- ao_enable_analog(0, 16, 5);
-#endif
-#if AO_ADC_6
- ao_enable_analog(0, 22, 6);
-#endif
-#if AO_ADC_7
- ao_enable_analog(0, 23, 7);
-#endif
-
- lpc_adc.cr = ((1 << (LPC_ADC_CR_SEL + 6)) |
- (AO_ADC_CLKDIV << LPC_ADC_CR_CLKDIV) |
- (1 << LPC_ADC_CR_BURST) |
- (LPC_ADC_CR_CLKS_9 << LPC_ADC_CR_CLKS));
-}
-
-static void
-ao_trng_adc_dump(void)
-{
- int i;
-
- while (((adc_head - adc_tail) & (ADC_RING_SIZE - 1)) < 16) {
- lpc_adc.inten = (1 << (LPC_ADC_INTEN_ADINTEN + 6));
- adc_wake = 16;
- ao_sleep(&adc_wake);
- }
- printf("adc_head %d tail %d\n", adc_head, adc_tail);
-
- for (i = 0; i < 16; i++) {
- printf(" %4d", adc_ring[adc_tail]);
- adc_tail = (adc_tail + 1) & (ADC_RING_SIZE - 1);
- }
- printf("\n");
- lpc_adc.inten = 0;
-}
-
-static void
-ao_trng_run(void)
-{
- uint16_t this_time;
- flush();
-
- while (!ao_usb_out_avail) {
- ao_arch_block_interrupts();
- while (((adc_head - adc_tail) & (ADC_RING_SIZE - 1)) < 64) {
- lpc_adc.inten = (1 << (LPC_ADC_INTEN_ADINTEN + 6));
- adc_wake = 64;
- ao_sleep(&adc_wake);
- }
- ao_arch_release_interrupts();
-
- this_time = ADC_RING_SIZE - adc_tail;
- if (this_time > 64)
- this_time = 64;
- ao_usb_write(&adc_ring[adc_tail], this_time);
- adc_tail = (adc_tail + this_time) & (ADC_RING_SIZE - 1);
- }
- lpc_adc.inten = 0;
-}
-
-static void
-ao_trng_speed(void)
-{
- ao_cmd_decimal();
-
- if (ao_cmd_lex_u32 == 0 || ao_cmd_status != ao_cmd_success) {
- ao_cmd_status = ao_cmd_success;
- printf ("Current spi speed %d\n", spi_speed);
- } else {
- spi_speed = ao_cmd_lex_u32;
- }
-}
-
-static const struct ao_cmds ao_trng_cmds[] = {
-// { ao_trng_test, "R\0Dump some random numbers" },
- { ao_trng_run, "s\0Send random bits until char" },
- { ao_trng_speed, "S <speed>\0Set SPI speed (48MHz/speed)" },
- { ao_trng_adc_dump, "a\0Dump ADC data" },
- { 0, NULL }
-};
-
-void
-main(void)
-{
- ao_clock_init();
- ao_task_init();
- ao_timer_init();
-
-// ao_spi_init();
- ao_usb_init();
-
- ao_trng_adc_init();
-
- ao_serial_init();
-
- ao_led_init(LEDS_AVAILABLE);
-
- ao_cmd_init();
-
- ao_cmd_register(ao_trng_cmds);
-
- ao_start_scheduler();
-}