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Diffstat (limited to 'c/src/lib/libbsp/arm/tms570/console/tms570-sci.c')
| -rw-r--r-- | c/src/lib/libbsp/arm/tms570/console/tms570-sci.c | 559 |
1 files changed, 559 insertions, 0 deletions
diff --git a/c/src/lib/libbsp/arm/tms570/console/tms570-sci.c b/c/src/lib/libbsp/arm/tms570/console/tms570-sci.c new file mode 100644 index 0000000000..8aa3cafcb3 --- /dev/null +++ b/c/src/lib/libbsp/arm/tms570/console/tms570-sci.c @@ -0,0 +1,559 @@ +/** + * @file tms570-sci.c + * + * @ingroup tms570 + * + * @brief Serial communication interface (SCI) functions definitions. + */ + +/* + * Copyright (c) 2014 Premysl Houdek <kom541000@gmail.com> + * + * Google Summer of Code 2014 at + * Czech Technical University in Prague + * Zikova 1903/4 + * 166 36 Praha 6 + * Czech Republic + * + * Based on LPC24xx and LPC1768 BSP + * by embedded brains GmbH and others + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * http://www.rtems.org/license/LICENSE. + */ + +#include <bspopts.h> +#include <termios.h> +#include <rtems/termiostypes.h> +#include <libchip/sersupp.h> +#include <bsp/tms570-sci.h> +#include <bsp/tms570-sci-driver.h> +#include <rtems/console.h> +#include <bsp.h> +#include <bsp/fatal.h> +#include <bsp/irq.h> + +#define TMS570_SCI_BUFFER_SIZE 1 + +/** + * @brief Table including all serial drivers + * + * Definitions of all serial drivers + */ +const tms570_sci_context driver_context_table[] = { + { + .device_name = "/dev/console", + .regs = &TMS570_SCI, + .irq = TMS570_IRQ_SCI_LEVEL_0, + }, + { + .device_name = "/dev/ttyS1", + .regs = &TMS570_SCI2, + .irq = TMS570_IRQ_SCI2_LEVEL_0, + } +}; + +/** + * @brief Serial drivers init function + * + * Initialize all serial drivers specified in driver_context_table + * + * @param[in] major + * @param[in] minor + * @param[in] arg + * @retval RTEMS_SUCCESSFUL Initialization completed + */ +rtems_device_driver console_initialize( + rtems_device_major_number major, + rtems_device_minor_number minor, + void *arg +) +{ + rtems_status_code sc; +#if CONSOLE_USE_INTERRUPTS + const rtems_termios_device_handler *handler = &tms570_sci_handler_interrupt; +#else + const rtems_termios_device_handler *handler = &tms570_sci_handler_polled; +#endif + + /* + * Initialize the Termios infrastructure. If Termios has already + * been initialized by another device driver, then this call will + * have no effect. + */ + rtems_termios_initialize(); + + /* Initialize each device */ + for ( + minor = 0; + minor < RTEMS_ARRAY_SIZE(driver_context_table); + ++minor + ) { + const tms570_sci_context *ctx = &driver_context_table[minor]; + + /* + * Install this device in the file system and Termios. In order + * to use the console (i.e. being able to do printf, scanf etc. + * on stdin, stdout and stderr), one device must be registered as + * "/dev/console" (CONSOLE_DEVICE_NAME). + */ + sc = rtems_termios_device_install( + ctx->device_name, + major, + minor, + handler, + (void *) ctx + ); + if ( sc != RTEMS_SUCCESSFUL ) { + bsp_fatal(BSP_FATAL_CONSOLE_NO_DEV); + } + } + return RTEMS_SUCCESSFUL; +} + +/** + * @brief Reads chars from HW + * + * Reads chars from HW peripheral specified in driver context. + * TMS570 does not have HW buffer for serial line so this function can + * return only 0 or 1 char + * + * @param[in] ctx context of the driver + * @param[out] buf read data buffer + * @param[in] N size of buffer + * @retval x Number of read chars from peripherals + */ +static int tms570_sci_read_received_chars( + tms570_sci_context * ctx, + char * buf, + int N) +{ + if ( N < 1 ) { + return 0; + } + if ( ctx->regs->SCIRD != 0 ) { + buf[0] = ctx->regs->SCIRD; + return 1; + } + return 0; +} + +/** + * @brief Enables RX interrupt + * + * Enables RX interrupt source of SCI peripheral + * specified in the driver context. + * + * @param[in] ctx context of the driver + * @retval Void + */ +static void tms570_sci_enable_interrupts(tms570_sci_context * ctx) +{ + ctx->regs->SCISETINT = (1<<9); +} + +/** + * @brief Disables RX interrupt + * + * Disables RX interrupt source of SCI peripheral specified in the driver + * context. + * + * @param[in] ctx context of the driver + * @retval Void + */ +static void tms570_sci_disable_interrupts(tms570_sci_context * ctx) +{ + ctx->regs->SCICLEARINT = (1<<9); +} + +/** + * @brief Check whether driver has put char in HW + * + * Check whether driver has put char in HW. + * This information is read from the driver context not from a peripheral. + * TMS570 does not have write data buffer asociated with SCI + * so the return can be only 0 or 1. + * + * @param[in] ctx context of the driver + * @retval x + */ +static int tms570_sci_transmitted_chars(tms570_sci_context * ctx) +{ + int ret; + + ret = ctx->tx_chars_in_hw; + if ( ret == 1 ) { + ctx->tx_chars_in_hw = 0; + return 1; + } + return ret; +} + +/** + * @brief Set attributes of the HW peripheral + * + * Sets attributes of the HW peripheral (parity, baud rate, etc.) + * + * @param[in] tty rtems_termios_tty + * @param[in] t termios driver + * @retval true peripheral setting is changed + */ +static bool tms570_sci_set_attributes( + rtems_termios_tty *tty, + const struct termios *t +) +{ + tms570_sci_context *ctx = rtems_termios_get_device_context(tty); + rtems_interrupt_lock_context lock_context; + int32_t bauddiv; + int32_t baudrate; + + rtems_termios_interrupt_lock_acquire(tty, &lock_context); + + ctx->regs->SCIGCR1 &= ~( (1<<7) | (1<<25) | (1<<24) ); + + ctx->regs->SCIGCR1 &= ~(1<<4); /*one stop bit*/ + ctx->regs->SCIFORMAT = 0x7; + + switch ( t->c_cflag & ( PARENB|PARODD ) ) { + case ( PARENB|PARODD ): + /* Odd parity */ + ctx->regs->SCIGCR1 &= ~(1<<3); + ctx->regs->SCIGCR1 |= (1<<2); + break; + + case PARENB: + /* Even parity */ + ctx->regs->SCIGCR1 |= (1<<3); + ctx->regs->SCIGCR1 |= (1<<2); + break; + + default: + case 0: + case PARODD: + /* No Parity */ + ctx->regs->SCIGCR1 &= ~(1<<2); + } + + /* Baud rate */ + baudrate = rtems_termios_baud_to_number(cfgetospeed(t)); + baudrate *= 2 * 16; + bauddiv = (BSP_PLL_OUT_CLOCK + baudrate / 2) / baudrate; + ctx->regs->BRS = bauddiv; + + ctx->regs->SCIGCR1 |= (1<<7) | (1<<25) | (1<<24); + + rtems_termios_interrupt_lock_release(tty, &lock_context); + + return true; +} + +/** + * @brief sci interrupt handler + * + * Handler checks which interrupt occured and provides nessesary maintenance + * dequeue characters in termios driver whether character is send succesfully + * enqueue characters in termios driver whether character is recieved + * + * @param[in] arg rtems_termios_tty + * @retval Void + */ +static void tms570_sci_interrupt_handler(void * arg) +{ + rtems_termios_tty *tty = arg; + tms570_sci_context *ctx = rtems_termios_get_device_context(tty); + char buf[TMS570_SCI_BUFFER_SIZE]; + size_t n; + + /* + * Check if we have received something. + */ + if ( (ctx->regs->SCIFLR & (1<<9) ) == (1<<9) ) { + n = tms570_sci_read_received_chars(ctx, buf, TMS570_SCI_BUFFER_SIZE); + if ( n > 0 ) { + /* Hand the data over to the Termios infrastructure */ + rtems_termios_enqueue_raw_characters(tty, buf, n); + } + } + /* + * Check if we have something transmitted. + */ + if ( (ctx->regs->SCIFLR & (1<<8) ) == (1<<8) ) { + n = tms570_sci_transmitted_chars(ctx); + if ( n > 0 ) { + /* + * Notify Termios that we have transmitted some characters. It + * will call now the interrupt write function if more characters + * are ready for transmission. + */ + rtems_termios_dequeue_characters(tty, n); + } + } +} + +/** + * @brief sci write function called from interrupt + * + * Nonblocking write function. Writes characters to HW peripheral + * TMS570 does not have write data buffer asociated with SCI + * so only one character can be written. + * + * @param[in] tty rtems_termios_tty + * @param[in] buf buffer of characters pending to send + * @param[in] len size of the buffer + * @retval Void + */ +static void tms570_sci_interrupt_write( + rtems_termios_tty *tty, + const char *buf, + size_t len +) +{ + tms570_sci_context *ctx = rtems_termios_get_device_context(tty); + + if ( len > 0 ) { + /* start UART TX, this will result in an interrupt when done */ + ctx->regs->SCITD = *buf; + /* character written - raise count*/ + ctx->tx_chars_in_hw = 1; + /* Enable TX interrupt (interrupt is edge-triggered) */ + ctx->regs->SCISETINT = (1<<8); + + } else { + /* No more to send, disable TX interrupts */ + ctx->regs->SCICLEARINT = (1<<8); + /* Tell close that we sent everything */ + } +} + +/** + * @brief sci write function + * + * Blocking write function. Waits until HW peripheral is ready and then writes + * character to HW peripheral. Writes all characters in the buffer. + * + * @param[in] tty rtems_termios_tty + * @param[in] buf buffer of characters pending to send + * @param[in] len size of the buffer + * @retval Void + */ +static void tms570_sci_poll_write( + rtems_termios_tty *tty, + const char *buf, + size_t n +) +{ + tms570_sci_context *ctx = rtems_termios_get_device_context(tty); + size_t i; + + /* Write */ + + for ( i = 0; i < n; ++i ) { + while ( (ctx->regs->SCIFLR & (1<<11) ) == 0) { + ; + } + ctx->regs->SCITD = buf[i]; + } +} + +/** + * @brief See if there is recieved charakter to read + * + * read the RX flag from peripheral specified in context + * + * @param[in] ctx context of the driver + * @retval 0 No character to read + * @retval x Character ready to read + */ +static int TMS570_sci_can_read_char( + tms570_sci_context * ctx +) +{ + return ctx->regs->SCIFLR & (1<<9); +} + +/** + * @brief reads character from peripheral + * + * reads the recieved character from peripheral specified in context + * + * @param[in] ctx context of the driver + * @retval x Character + */ +static char TMS570_sci_read_char( + tms570_sci_context * ctx +) +{ + return ctx->regs->SCIRD; +} + +/** + * @brief sci read function + * + * check if there is recieved character to be read and reads it. + * + * @param[in] tty rtems_termios_tty (context of the driver) + * @retval -1 No character to be read + * @retval x Read character + */ +static int tms570_sci_poll_read(rtems_termios_tty *tty) +{ + tms570_sci_context *ctx = rtems_termios_get_device_context(tty); + + /* Check if a character is available */ + if ( TMS570_sci_can_read_char(ctx) ) { + return TMS570_sci_read_char(ctx); + } else { + return -1; + } +} + +/** + * @brief initialization of the driver + * + * initialization of the HW peripheral specified in contex of the driver. + * This function is called only once when opening the driver. + * + * @param[in] tty context of the driver + * @param[in] args + * @retval false Error occured during initialization + * @retval true Driver is open and ready + */ +static bool tms570_sci_poll_first_open( + rtems_termios_tty *tty, + rtems_libio_open_close_args_t *args +) +{ + bool ok; + + rtems_termios_set_best_baud(tty, TMS570_SCI_BAUD_RATE); + ok = tms570_sci_set_attributes(tty, rtems_termios_get_termios(tty)); + if ( !ok ) { + return false; + } + return true; +} + +/** + * @brief initialization of the interrupt driven driver + * + * calls tms570_sci_poll_first_open function. + * install and enables interrupts. + * + * @param[in] tty context of the driver + * @param[in] args + * @retval false Error occured during initialization + * @retval true Driver is open and ready + */ +static bool tms570_sci_interrupt_first_open( + rtems_termios_tty *tty, + rtems_libio_open_close_args_t *args +) +{ + tms570_sci_context *ctx = rtems_termios_get_device_context(tty); + rtems_status_code sc; + bool ret; + + ret = tms570_sci_poll_first_open(tty,args); + if ( ret == false ) { + return false; + } + ctx->regs->SCISETINTLVL = 0; + /* Register Interrupt handler */ + sc = rtems_interrupt_handler_install(ctx->irq, + ctx->device_name, + RTEMS_INTERRUPT_SHARED, + tms570_sci_interrupt_handler, + tty + ); + if ( sc != RTEMS_SUCCESSFUL ) { + return false; + } + tms570_sci_enable_interrupts(rtems_termios_get_device_context(tty)); + return true; +} + +/** + * @brief closes sci peripheral + * + * @param[in] tty context of the driver + * @param[in] args + * @retval false Error occured during initialization + * @retval true Driver is open and ready + */ +static void tms570_sci_poll_last_close( + rtems_termios_tty *tty, + rtems_libio_open_close_args_t *args +) +{ + ; +} + +/** + * @brief closes sci peripheral of interrupt driven driver + * + * calls tms570_sci_poll_last_close and disables interrupts + * + * @param[in] tty context of the driver + * @param[in] args + * @retval false Error occured during initialization + * @retval true Driver is open and ready + */ +static void tms570_sci_interrupt_last_close( + rtems_termios_tty *tty, + rtems_libio_open_close_args_t *args +) +{ + tms570_sci_context *ctx = rtems_termios_get_device_context(tty); + rtems_interrupt_lock_context lock_context; + + /* Turn off RX interrupts */ + rtems_termios_interrupt_lock_acquire(tty, &lock_context); + tms570_sci_disable_interrupts(ctx); + rtems_termios_interrupt_lock_release(tty, &lock_context); + + /* Flush device */ + while ( ( ctx->regs->SCIFLR & (1<<11) ) > 0 ) { + ;/* Wait until all data has been sent */ + } + + /* uninstall ISR */ + rtems_interrupt_handler_remove(ctx->irq, tms570_sci_interrupt_handler, tty); + + tms570_sci_poll_last_close(tty,args); +} + +/** + * @brief Struct containing definitions of polled driver functions. + * + * Encapsulates polled driver functions. + * Use of this table is determited by not defining TMS570_USE_INTERRUPTS + */ +const rtems_termios_device_handler tms570_sci_handler_polled = { + .first_open = tms570_sci_poll_first_open, + .last_close = tms570_sci_poll_last_close, + .poll_read = tms570_sci_poll_read, + .write = tms570_sci_poll_write, + .set_attributes = tms570_sci_set_attributes, + .stop_remote_tx = NULL, + .start_remote_tx = NULL, + .mode = TERMIOS_POLLED +}; + +/** + * @brief Struct containing definitions of interrupt driven driver functions. + * + * Encapsulates interrupt driven driver functions. + * Use of this table is determited by defining TMS570_USE_INTERRUPTS + */ +const rtems_termios_device_handler tms570_sci_handler_interrupt = { + .first_open = tms570_sci_interrupt_first_open, + .last_close = tms570_sci_interrupt_last_close, + .poll_read = NULL, + .write = tms570_sci_interrupt_write, + .set_attributes = tms570_sci_set_attributes, + .stop_remote_tx = NULL, + .start_remote_tx = NULL, + .mode = TERMIOS_IRQ_DRIVEN +}; 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