From 1e9a164e22976933002c5e4b0b79b09fcede9cd4 Mon Sep 17 00:00:00 2001 From: Daniel Hellstrom Date: Wed, 26 Mar 2008 22:51:29 +0100 Subject: SPARC: Added support for SPARC LEON3 SOC processor. Signed-off-by: Daniel Hellstrom --- cpu/leon3/serial.c | 139 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 139 insertions(+) create mode 100644 cpu/leon3/serial.c (limited to 'cpu/leon3/serial.c') diff --git a/cpu/leon3/serial.c b/cpu/leon3/serial.c new file mode 100644 index 0000000..27d5cd3 --- /dev/null +++ b/cpu/leon3/serial.c @@ -0,0 +1,139 @@ +/* GRLIB APBUART Serial controller driver + * + * (C) Copyright 2007 + * 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 +#include +#include +#include + +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 + +ambapp_dev_apbuart *leon3_apbuart = NULL; + +int serial_init(void) +{ + ambapp_apbdev apbdev; + unsigned int tmp; + + /* find UART */ + if (ambapp_apb_first(VENDOR_GAISLER, GAISLER_APBUART, &apbdev) == 1) { + + leon3_apbuart = (ambapp_dev_apbuart *) apbdev.address; + + /* found apbuart, let's init... + * + * Set scaler / baud rate + * + * Receiver & transmitter enable + */ + leon3_apbuart->scaler = CFG_GRLIB_APBUART_SCALER; + + /* Let bit 11 be unchanged (debug bit for GRMON) */ + tmp = READ_WORD(leon3_apbuart->ctrl); + + leon3_apbuart->ctrl = ((tmp & LEON_REG_UART_CTRL_DBG) | + LEON_REG_UART_CTRL_RE | + LEON_REG_UART_CTRL_TE); + + return 0; + } + return -1; /* didn't find hardware */ +} + +void serial_putc(const char c) +{ + if (c == '\n') + serial_putc_raw('\r'); + + serial_putc_raw(c); +} + +void serial_putc_raw(const char c) +{ + if (!leon3_apbuart) + return; + + /* Wait for last character to go. */ + while (!(READ_WORD(leon3_apbuart->status) & LEON_REG_UART_STATUS_THE)) ; + + /* Send data */ + leon3_apbuart->data = c; + +#ifdef LEON_DEBUG + /* Wait for data to be sent */ + while (!(READ_WORD(leon3_apbuart->status) & LEON_REG_UART_STATUS_TSE)) ; +#endif +} + +void serial_puts(const char *s) +{ + while (*s) { + serial_putc(*s++); + } +} + +int serial_getc(void) +{ + if (!leon3_apbuart) + return 0; + + /* Wait for a character to arrive. */ + while (!(READ_WORD(leon3_apbuart->status) & LEON_REG_UART_STATUS_DR)) ; + + /* read data */ + return READ_WORD(leon3_apbuart->data); +} + +int serial_tstc(void) +{ + if (leon3_apbuart) + return (READ_WORD(leon3_apbuart->status) & + LEON_REG_UART_STATUS_DR); + return 0; +} + +/* set baud rate for uart */ +void serial_setbrg(void) +{ + /* update baud rate settings, read it from gd->baudrate */ + unsigned int scaler; + if (leon3_apbuart && (gd->baudrate > 0)) { + scaler = + (((CONFIG_SYS_CLK_FREQ * 10) / (gd->baudrate * 8)) - + 5) / 10; + leon3_apbuart->scaler = scaler; + } + return; +} -- cgit v1.1