diff options
Diffstat (limited to 'c/src/lib/libcpu/arm/at91rm9200/dbgu/dbgu.c')
| -rw-r--r-- | c/src/lib/libcpu/arm/at91rm9200/dbgu/dbgu.c | 221 |
1 files changed, 221 insertions, 0 deletions
diff --git a/c/src/lib/libcpu/arm/at91rm9200/dbgu/dbgu.c b/c/src/lib/libcpu/arm/at91rm9200/dbgu/dbgu.c new file mode 100644 index 0000000000..e18f281512 --- /dev/null +++ b/c/src/lib/libcpu/arm/at91rm9200/dbgu/dbgu.c @@ -0,0 +1,221 @@ +/* + * Console driver for AT91RM9200 DBGU port + * + * This driver uses the shared console driver in + * ...../libbsp/shared/console.c + * + * Copyright (c) 2003 by Cogent Computer Systems + * Written by Mike Kelly <mike@cogcomp.com> + * and Jay Monkman <jtm@lopingdog.com> + * + * The license and distribution terms for this file may be + * found in the file LICENSE in this distribution or at + * + * http://www.OARcorp.com/rtems/license.html. + * + * $Id$ + */ +#include <bsp.h> +#include <rtems/libio.h> +#include <termios.h> + +#include <at91rm9200.h> +#include <at91rm9200_dbgu.h> +#include <at91rm9200_pmc.h> +#include <rtems/bspIo.h> +#include <libchip/serial.h> +#include <libchip/sersupp.h> + +volatile int dbg_dly; + +/* static function prototypes */ +static int dbgu_first_open(int major, int minor, void *arg); +static int dbgu_last_close(int major, int minor, void *arg); +static int dbgu_read(int minor); +static int dbgu_write(int minor, const char *buf, int len); +static void dbgu_init(int minor); +static void dbgu_write_polled(int minor, char c); +static int dbgu_set_attributes(int minor, const struct termios *t); + +/* Pointers to functions for handling the UART. */ +console_fns dbgu_fns = +{ + libchip_serial_default_probe, + dbgu_first_open, + dbgu_last_close, + dbgu_read, + dbgu_write, + dbgu_init, + dbgu_write_polled, /* not used in this driver */ + dbgu_set_attributes, + FALSE /* TRUE if interrupt driven, FALSE if not. */ +}; +/*********************************************************************/ +/* Functions called via callbacks (i.e. the ones in uart_fns */ +/*********************************************************************/ + +/* + * This is called the first time each device is opened. Since + * the driver is polled, we don't have to do anything. If the driver + * were interrupt driven, we'd enable interrupts here. + */ +static int dbgu_first_open(int major, int minor, void *arg) +{ + return 0; +} + + +/* + * This is called the last time each device is closed. Since + * the driver is polled, we don't have to do anything. If the driver + * were interrupt driven, we'd disable interrupts here. + */ +static int dbgu_last_close(int major, int minor, void *arg) +{ + return 0; +} + + +/* + * Read one character from UART. + * + * return -1 if there's no data, otherwise return + * the character in lowest 8 bits of returned int. + */ +static int dbgu_read(int minor) +{ + char c; + console_tbl *console_entry; + at91rm9200_dbgu_regs_t *dbgu; + + console_entry = BSP_get_uart_from_minor(minor); + + if (console_entry == NULL) { + return -1; + } + + dbgu = (at91rm9200_dbgu_regs_t *)console_entry->ulCtrlPort1; + + if (!(dbgu->sr & DBGU_INT_RXRDY)) { + return -1; + } + + c = dbgu->rhr & 0xff; + + return c; +} + + +/* + * Write buffer to UART + * + * return 1 on success, -1 on error + */ +static int dbgu_write(int minor, const char *buf, int len) +{ + int i, x; + char c; + console_tbl *console_entry; + at91rm9200_dbgu_regs_t *dbgu; + + console_entry = BSP_get_uart_from_minor(minor); + + if (console_entry == NULL) { + return -1; + } + + dbgu = (at91rm9200_dbgu_regs_t *)console_entry->ulCtrlPort1; + + for (i = 0; i < len; i++) { + /* Wait for fifo to have room */ + while(1) { + if (dbgu->sr & DBGU_INT_TXRDY) { + break; + } + } + + c = (char) buf[i]; + dbgu->thr = c; + + /* the TXRDY flag does not seem to update right away (is this true?) */ + /* so we wait a bit before continuing */ + for (x = 0; x < 100; x++) { + dbg_dly++; /* using a global so this doesn't get optimized out */ + } + } + + return 1; +} + + +/* Set up the UART. */ +static void dbgu_init(int minor) +{ + console_tbl *console_entry; + at91rm9200_dbgu_regs_t *dbgu; + + console_entry = BSP_get_uart_from_minor(minor); + + if (console_entry == NULL) { + return; + } + + dbgu = (at91rm9200_dbgu_regs_t *)console_entry->ulCtrlPort1; + + /* Clear error bits, and reset */ + dbgu->cr = (DBGU_CR_RSTSTA | DBGU_CR_RSTTX | DBGU_CR_RSTRX); + + /* Clear pending interrupts */ + dbgu->idr = DBGU_INT_ALL; + dbgu->imr = 0; + + /* Set port to no parity, no loopback */ + dbgu->mr = DBGU_MR_PAR_NONE | DBGU_MR_CHMODE_NORM; + + /* Set the baud rate */ + dbgu->brgr = (at91rm9200_get_mck() / 16) / BSP_get_baud(); + + /* Enable the DBGU */ + dbgu->cr = (DBGU_CR_TXEN | DBGU_CR_RXEN); +} + +/* I'm not sure this is needed for the shared console driver. */ +static void dbgu_write_polled(int minor, char c) +{ + dbgu_write(minor, &c, 1); +} + +/* This is for setting baud rate, bits, etc. */ +static int dbgu_set_attributes(int minor, const struct termios *t) +{ + return 0; +} + +/***********************************************************************/ +/* + * The following functions are not used by TERMIOS, but other RTEMS + * functions use them instead. + */ +/***********************************************************************/ +/* + * Read from UART. This is used in the exit code, and can't + * rely on interrupts. + */ +int dbgu_poll_read(int minor) +{ + return dbgu_read(minor); +} + + +/* + * Write a character to the console. This is used by printk() and + * maybe other low level functions. It should not use interrupts or any + * RTEMS system calls. It needs to be very simple + */ +static void _BSP_put_char( char c ) { + dbgu_write_polled(0, c); +} + +BSP_output_char_function_type BSP_output_char = _BSP_put_char; + + |