diff options
Diffstat (limited to 'src/stm/ao_serial_stm.c')
| -rw-r--r-- | src/stm/ao_serial_stm.c | 401 |
1 files changed, 401 insertions, 0 deletions
diff --git a/src/stm/ao_serial_stm.c b/src/stm/ao_serial_stm.c new file mode 100644 index 00000000..406da9fb --- /dev/null +++ b/src/stm/ao_serial_stm.c @@ -0,0 +1,401 @@ +/* + * Copyright © 2012 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; version 2 of the License. + * + * 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> + +struct ao_stm_usart { + struct ao_fifo rx_fifo; + struct ao_fifo tx_fifo; + struct stm_usart *reg; + uint8_t tx_started; +}; + +void +ao_debug_out(char c) +{ + if (c == '\n') + ao_debug_out('\r'); + while (!(stm_usart1.sr & (1 << STM_USART_SR_TXE))); + stm_usart1.dr = c; +} + +static void +ao_usart_tx_start(struct ao_stm_usart *usart) +{ + if (!ao_fifo_empty(usart->tx_fifo) && !usart->tx_started) + { + usart->tx_started = 1; + ao_fifo_remove(usart->tx_fifo, usart->reg->dr); + } +} + +static void +ao_usart_isr(struct ao_stm_usart *usart, int stdin) +{ + uint32_t sr; + + sr = usart->reg->sr; + usart->reg->sr = 0; + + if (sr & (1 << STM_USART_SR_RXNE)) { + char c = usart->reg->dr; + if (!ao_fifo_full(usart->rx_fifo)) + ao_fifo_insert(usart->rx_fifo, c); + ao_wakeup(&usart->rx_fifo); + if (stdin) + ao_wakeup(&ao_stdin_ready); + } + if (sr & (1 << STM_USART_SR_TC)) { + usart->tx_started = 0; + ao_usart_tx_start(usart); + ao_wakeup(&usart->tx_fifo); + } +} + +char +ao_usart_getchar(struct ao_stm_usart *usart) +{ + char c; + cli(); + while (ao_fifo_empty(usart->rx_fifo)) + ao_sleep(&usart->rx_fifo); + ao_fifo_remove(usart->rx_fifo, c); + sei(); + return c; +} + +char +ao_usart_pollchar(struct ao_stm_usart *usart) +{ + char c; + cli(); + if (ao_fifo_empty(usart->rx_fifo)) { + sei(); + return AO_READ_AGAIN; + } + ao_fifo_remove(usart->rx_fifo,c); + sei(); + return c; +} + +void +ao_usart_putchar(struct ao_stm_usart *usart, char c) +{ + cli(); + while (ao_fifo_full(usart->tx_fifo)) + ao_sleep(&usart->tx_fifo); + ao_fifo_insert(usart->tx_fifo, c); + ao_usart_tx_start(usart); + sei(); +} + +void +ao_usart_drain(struct ao_stm_usart *usart) +{ + cli(); + while (!ao_fifo_empty(usart->tx_fifo)) + ao_sleep(&usart->tx_fifo); + sei(); +} + +static const struct { + uint32_t brr; +} ao_usart_speeds[] = { + [AO_SERIAL_SPEED_4800] = { + AO_PCLK1 / 4800 + }, + [AO_SERIAL_SPEED_9600] = { + AO_PCLK1 / 9600 + }, + [AO_SERIAL_SPEED_19200] = { + AO_PCLK1 / 19200 + }, + [AO_SERIAL_SPEED_57600] = { + AO_PCLK1 / 57600 + }, +}; + +void +ao_usart_set_speed(struct ao_stm_usart *usart, uint8_t speed) +{ + if (speed > AO_SERIAL_SPEED_57600) + return; + usart->reg->brr = ao_usart_speeds[speed].brr; +} + +void +ao_usart_init(struct ao_stm_usart *usart) +{ + usart->reg->cr1 = ((0 << STM_USART_CR1_OVER8) | + (1 << STM_USART_CR1_UE) | + (0 << STM_USART_CR1_M) | + (0 << STM_USART_CR1_WAKE) | + (0 << STM_USART_CR1_PCE) | + (0 << STM_USART_CR1_PS) | + (0 << STM_USART_CR1_PEIE) | + (0 << STM_USART_CR1_TXEIE) | + (1 << STM_USART_CR1_TCIE) | + (1 << STM_USART_CR1_RXNEIE) | + (0 << STM_USART_CR1_IDLEIE) | + (1 << STM_USART_CR1_TE) | + (1 << STM_USART_CR1_RE) | + (0 << STM_USART_CR1_RWU) | + (0 << STM_USART_CR1_SBK)); + + usart->reg->cr2 = ((0 << STM_USART_CR2_LINEN) | + (STM_USART_CR2_STOP_1 << STM_USART_CR2_STOP) | + (0 << STM_USART_CR2_CLKEN) | + (0 << STM_USART_CR2_CPOL) | + (0 << STM_USART_CR2_CPHA) | + (0 << STM_USART_CR2_LBCL) | + (0 << STM_USART_CR2_LBDIE) | + (0 << STM_USART_CR2_LBDL) | + (0 << STM_USART_CR2_ADD)); + + usart->reg->cr3 = ((0 << STM_USART_CR3_ONEBITE) | + (0 << STM_USART_CR3_CTSIE) | + (0 << STM_USART_CR3_CTSE) | + (0 << STM_USART_CR3_RTSE) | + (0 << STM_USART_CR3_DMAT) | + (0 << STM_USART_CR3_DMAR) | + (0 << STM_USART_CR3_SCEN) | + (0 << STM_USART_CR3_NACK) | + (0 << STM_USART_CR3_HDSEL) | + (0 << STM_USART_CR3_IRLP) | + (0 << STM_USART_CR3_IREN) | + (0 << STM_USART_CR3_EIE)); + + /* Pick a 9600 baud rate */ + ao_usart_set_speed(usart, AO_SERIAL_SPEED_9600); +} + +#if HAS_SERIAL_1 + +struct ao_stm_usart ao_stm_usart1; + +void stm_usart1_isr(void) { ao_usart_isr(&ao_stm_usart1, USE_SERIAL_1_STDIN); } + +char +ao_serial1_getchar(void) +{ + return ao_usart_getchar(&ao_stm_usart1); +} + +void +ao_serial1_putchar(char c) +{ + ao_usart_putchar(&ao_stm_usart1, c); +} + +char +ao_serial1_pollchar(void) +{ + return ao_usart_pollchar(&ao_stm_usart1); +} + +void +ao_serial1_set_speed(uint8_t speed) +{ + ao_usart_set_speed(&ao_stm_usart1, speed); +} +#endif /* HAS_SERIAL_1 */ + +#if HAS_SERIAL_2 + +struct ao_stm_usart ao_stm_usart2; + +void stm_usart2_isr(void) { ao_usart_isr(&ao_stm_usart2, USE_SERIAL_2_STDIN); } + +char +ao_serial2_getchar(void) +{ + return ao_usart_getchar(&ao_stm_usart2); +} + +void +ao_serial2_putchar(char c) +{ + ao_usart_putchar(&ao_stm_usart2, c); +} + +char +ao_serial2_pollchar(void) +{ + return ao_usart_pollchar(&ao_stm_usart2); +} + +void +ao_serial2_set_speed(uint8_t speed) +{ + ao_usart_set_speed(&ao_stm_usart2, speed); +} +#endif /* HAS_SERIAL_2 */ + +#if HAS_SERIAL_3 + +struct ao_stm_usart ao_stm_usart3; + +void stm_usart3_isr(void) { ao_usart_isr(&ao_stm_usart3, USE_SERIAL_2_STDIN); } + +char +ao_serial3_getchar(void) +{ + return ao_usart_getchar(&ao_stm_usart3); +} + +void +ao_serial3_putchar(char c) +{ + ao_usart_putchar(&ao_stm_usart3, c); +} + +char +ao_serial3_pollchar(void) +{ + return ao_usart_pollchar(&ao_stm_usart3); +} + +void +ao_serial3_set_speed(uint8_t speed) +{ + ao_usart_set_speed(&ao_stm_usart3, speed); +} +#endif /* HAS_SERIAL_3 */ + +void +ao_serial_init(void) +{ +#if HAS_SERIAL_1 + /* + * TX RX + * PA9 PA10 + * PB6 PB7 * + */ + +#if SERIAL_1_PA9_PA10 + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOAEN); + + stm_afr_set(&stm_gpioa, 9, STM_AFR_AF7); + stm_afr_set(&stm_gpioa, 10, STM_AFR_AF7); +#else +#if SERIAL_1_PB6_PB7 + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOBEN); + + stm_afr_set(&stm_gpiob, 6, STM_AFR_AF7); + stm_afr_set(&stm_gpiob, 7, STM_AFR_AF7); +#else +#error "No SERIAL_1 port configuration specified" +#endif +#endif + /* Enable USART */ + stm_rcc.apb2enr |= (1 << STM_RCC_APB2ENR_USART1EN); + + ao_stm_usart1.reg = &stm_usart1; + ao_usart_init(&ao_stm_usart1); + + stm_nvic_set_enable(STM_ISR_USART1_POS); + stm_nvic_set_priority(STM_ISR_USART1_POS, 4); +#if USE_SERIAL_1_STDIN + ao_add_stdio(ao_serial1_pollchar, + ao_serial1_putchar, + NULL); +#endif +#endif + +#if HAS_SERIAL_2 + /* + * TX RX + * PA2 PA3 + * PD5 PD6 + */ + +#if SERIAL_2_PA2_PA3 + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOAEN); + + stm_afr_set(&stm_gpioa, 2, STM_AFR_AF7); + stm_afr_set(&stm_gpioa, 3, STM_AFR_AF7); +#else +#if SERIAL_2_PD5_PD6 + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIODEN); + + stm_afr_set(&stm_gpiod, 5, STM_AFR_AF7); + stm_afr_set(&stm_gpiod, 6, STM_AFR_AF7); +#else +#error "No SERIAL_2 port configuration specified" +#endif +#endif + /* Enable USART */ + stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_USART2EN); + + ao_stm_usart2.reg = &stm_usart2; + ao_usart_init(&ao_stm_usart2); + + stm_nvic_set_enable(STM_ISR_USART2_POS); + stm_nvic_set_priority(STM_ISR_USART2_POS, 4); +#if USE_SERIAL_2_STDIN + ao_add_stdio(ao_serial2_pollchar, + ao_serial2_putchar, + NULL); +#endif +#endif + +#if HAS_SERIAL_3 + /* + * TX RX + * PB10 PB11 + * PC10 PC11 + * PD8 PD9 + */ +#if SERIAL_3_PB10_PB11 + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOBEN); + + stm_afr_set(&stm_gpiob, 10, STM_AFR_AF7); + stm_afr_set(&stm_gpiob, 11, STM_AFR_AF7); +#else +#if SERIAL_3_PC10_PC11 + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIOCEN); + + stm_afr_set(&stm_gpioc, 10, STM_AFR_AF7); + stm_afr_set(&stm_gpioc, 11, STM_AFR_AF7); +#else +#if SERIAL_3_PD8_PD9 + stm_rcc.ahbenr |= (1 << STM_RCC_AHBENR_GPIODEN); + + stm_afr_set(&stm_gpiod, 8, STM_AFR_AF7); + stm_afr_set(&stm_gpiod, 9, STM_AFR_AF7); +#else +#error "No SERIAL_3 port configuration specified" +#endif +#endif +#endif + /* Enable USART */ + stm_rcc.apb1enr |= (1 << STM_RCC_APB1ENR_USART3EN); + + ao_stm_usart3.reg = &stm_usart3; + ao_usart_init(&ao_stm_usart3); + + stm_nvic_set_enable(STM_ISR_USART3_POS); + stm_nvic_set_priority(STM_ISR_USART3_POS, 4); +#if USE_SERIAL_3_STDIN + ao_add_stdio(ao_serial3_pollchar, + ao_serial3_putchar, + NULL); +#endif +#endif +} + + |