diff options
Diffstat (limited to 'cpu/leon2/serial.c')
| -rw-r--r-- | cpu/leon2/serial.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/cpu/leon2/serial.c b/cpu/leon2/serial.c new file mode 100644 index 0000000..ce9457f --- /dev/null +++ b/cpu/leon2/serial.c @@ -0,0 +1,165 @@ +/* GRLIB APBUART Serial controller driver + * + * (C) Copyright 2008 + * Daniel Hellstrom, Gaisler Research, daniel@gaisler.com. + * + * See file CREDITS for list of people who contributed to this + * project. + * + * 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 <common.h> +#include <asm/processor.h> +#include <asm/leon.h> + +DECLARE_GLOBAL_DATA_PTR; + +/* Force cache miss each time a serial controller reg is read */ +#define CACHE_BYPASS 1 + +#ifdef CACHE_BYPASS +#define READ_BYTE(var) SPARC_NOCACHE_READ_BYTE((unsigned int)&(var)) +#define READ_HWORD(var) SPARC_NOCACHE_READ_HWORD((unsigned int)&(var)) +#define READ_WORD(var) SPARC_NOCACHE_READ((unsigned int)&(var)) +#define READ_DWORD(var) SPARC_NOCACHE_READ_DWORD((unsigned int)&(var)) +#endif + +int serial_init(void) +{ + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + LEON2_Uart_regs *regs; + unsigned int tmp; + + /* Init LEON2 UART + * + * Set scaler / baud rate + * + * Receiver & transmitter enable + */ +#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1 + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1; +#else + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2; +#endif + + regs->UART_Scaler = CFG_LEON2_UART1_SCALER; + + /* Let bit 11 be unchanged (debug bit for GRMON) */ + tmp = READ_WORD(regs->UART_Control); + + regs->UART_Control = ((tmp & LEON2_UART_CTRL_DBG) | + (LEON2_UART1_LOOPBACK_ENABLE << 7) | + (LEON2_UART1_FLOWCTRL_ENABLE << 6) | + (LEON2_UART1_PARITY_ENABLE << 5) | + (LEON2_UART1_ODDPAR_ENABLE << 4) | + LEON2_UART_CTRL_RE | LEON2_UART_CTRL_TE); + + return 0; +} + +void serial_putc(const char c) +{ + if (c == '\n') + serial_putc_raw('\r'); + + serial_putc_raw(c); +} + +void serial_putc_raw(const char c) +{ + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + LEON2_Uart_regs *regs; + +#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1 + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1; +#else + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2; +#endif + + /* Wait for last character to go. */ + while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_THE)) ; + + /* Send data */ + regs->UART_Channel = c; + +#ifdef LEON_DEBUG + /* Wait for data to be sent */ + while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_TSE)) ; +#endif +} + +void serial_puts(const char *s) +{ + while (*s) { + serial_putc(*s++); + } +} + +int serial_getc(void) +{ + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + LEON2_Uart_regs *regs; + +#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1 + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1; +#else + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2; +#endif + + /* Wait for a character to arrive. */ + while (!(READ_WORD(regs->UART_Status) & LEON2_UART_STAT_DR)) ; + + /* read data */ + return READ_WORD(regs->UART_Channel); +} + +int serial_tstc(void) +{ + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + LEON2_Uart_regs *regs; + +#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1 + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1; +#else + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2; +#endif + + return (READ_WORD(regs->UART_Status) & LEON2_UART_STAT_DR); +} + +/* set baud rate for uart */ +void serial_setbrg(void) +{ + /* update baud rate settings, read it from gd->baudrate */ + unsigned int scaler; + LEON2_regs *leon2 = (LEON2_regs *) LEON2_PREGS; + LEON2_Uart_regs *regs; + +#if LEON2_CONSOLE_SELECT == LEON_CONSOLE_UART1 + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_1; +#else + regs = (LEON2_Uart_regs *) & leon2->UART_Channel_2; +#endif + + if (gd->baudrate > 0) { + scaler = + (((CONFIG_SYS_CLK_FREQ * 10) / (gd->baudrate * 8)) - + 5) / 10; + regs->UART_Scaler = scaler; + } +} |