diff options
-rw-r--r-- | cpu/nios2/serial.c | 168 | ||||
-rw-r--r-- | include/nios2-yanu.h | 115 |
2 files changed, 282 insertions, 1 deletions
diff --git a/cpu/nios2/serial.c b/cpu/nios2/serial.c index 8bbb803..6c835af 100644 --- a/cpu/nios2/serial.c +++ b/cpu/nios2/serial.c @@ -2,6 +2,9 @@ * (C) Copyright 2004, Psyent Corporation <www.psyent.com> * Scott McNutt <smcnutt@psyent.com> * + * YANU Support: + * Copyright 2010, Renato Andreola <renato.andreola@imagos.it> + * * See file CREDITS for list of people who contributed to this * project. * @@ -26,6 +29,7 @@ #include <watchdog.h> #include <asm/io.h> #include <nios2-io.h> +#include <nios2-yanu.h> DECLARE_GLOBAL_DATA_PTR; @@ -74,10 +78,172 @@ int serial_getc (void) return (c); } +#elif defined(CONFIG_CONSOLE_YANU) +/*-----------------------------------------------------------------*/ +/* YANU Imagos serial port */ +/*-----------------------------------------------------------------*/ + +static yanu_uart_t *uart = (yanu_uart_t *)CONFIG_SYS_NIOS_CONSOLE; + +#if defined(CONFIG_SYS_NIOS_FIXEDBAUD) + +/* Everything's already setup for fixed-baud PTF assignment*/ + +void serial_setbrg (void) +{ + int n, k; + const unsigned max_uns = 0xFFFFFFFF; + unsigned best_n, best_m, baud; + + /* compute best N and M couple */ + best_n = YANU_MAX_PRESCALER_N; + for (n = YANU_MAX_PRESCALER_N; n >= 0; n--) { + if ((unsigned)CONFIG_SYS_CLK_FREQ / (1 << (n + 4)) >= + (unsigned)CONFIG_BAUDRATE) { + best_n = n; + break; + } + } + for (k = 0;; k++) { + if ((unsigned)CONFIG_BAUDRATE <= (max_uns >> (15+n-k))) + break; + } + best_m = + ((unsigned)CONFIG_BAUDRATE * (1 << (15 + n - k))) / + ((unsigned)CONFIG_SYS_CLK_FREQ >> k); + + baud = best_m + best_n * YANU_BAUDE; + writel(&uart->baud, baud); + + return; +} + +#else + +void serial_setbrg (void) +{ + int n, k; + const unsigned max_uns = 0xFFFFFFFF; + unsigned best_n, best_m, baud; + + /* compute best N and M couple */ + best_n = YANU_MAX_PRESCALER_N; + for (n = YANU_MAX_PRESCALER_N; n >= 0; n--) { + if ((unsigned)CONFIG_SYS_CLK_FREQ / (1 << (n + 4)) >= + gd->baudrate) { + best_n = n; + break; + } + } + for (k = 0;; k++) { + if (gd->baudrate <= (max_uns >> (15+n-k))) + break; + } + best_m = + (gd->baudrate * (1 << (15 + n - k))) / + ((unsigned)CONFIG_SYS_CLK_FREQ >> k); + + baud = best_m + best_n * YANU_BAUDE; + writel(&uart->baud, baud); + + return; +} + + +#endif /* CONFIG_SYS_NIOS_FIXEDBAUD */ + +int serial_init (void) +{ + unsigned action,control; + + /* status register cleanup */ + action = YANU_ACTION_RRRDY | + YANU_ACTION_RTRDY | + YANU_ACTION_ROE | + YANU_ACTION_RBRK | + YANU_ACTION_RFE | + YANU_ACTION_RPE | + YANU_ACTION_RFE | YANU_ACTION_RFIFO_CLEAR | YANU_ACTION_TFIFO_CLEAR; + + writel(&uart->action, action); + + /* control register cleanup */ + /* no interrupts enabled */ + /* one stop bit */ + /* hardware flow control disabled */ + /* 8 bits */ + control = (0x7 << YANU_CONTROL_BITS_POS); + /* enven parity just to be clean */ + control |= YANU_CONTROL_PAREVEN; + /* we set threshold for fifo */ + control |= YANU_CONTROL_RDYDLY * YANU_RXFIFO_DLY; + control |= YANU_CONTROL_TXTHR * YANU_TXFIFO_THR; + + writel(&uart->control, control); + + /* to set baud rate */ + serial_setbrg(); + + return (0); +} + + +/*----------------------------------------------------------------------- + * YANU CONSOLE + *---------------------------------------------------------------------*/ +void serial_putc (char c) +{ + int tx_chars; + unsigned status; + + if (c == '\n') + serial_putc ('\r'); + + while (1) { + status = readl(&uart->status); + tx_chars = (status>>YANU_TFIFO_CHARS_POS) + & ((1<<YANU_TFIFO_CHARS_N)-1); + if (tx_chars < YANU_TXFIFO_SIZE-1) + break; + WATCHDOG_RESET (); + } + + writel(&uart->data, (unsigned char)c); +} + +void serial_puts (const char *s) +{ + while (*s != 0) { + serial_putc (*s++); + } +} + + +int serial_tstc(void) +{ + unsigned status ; + + status = readl(&uart->status); + return (((status >> YANU_RFIFO_CHARS_POS) & + ((1 << YANU_RFIFO_CHARS_N) - 1)) > 0); +} + +int serial_getc (void) +{ + while (serial_tstc() == 0) + WATCHDOG_RESET (); + + /* first we pull the char */ + writel(&uart->action, YANU_ACTION_RFIFO_PULL); + + return(readl(&uart->data) & YANU_DATA_CHAR_MASK); +} + +#else /*CONFIG_CONSOLE_YANU*/ + /*------------------------------------------------------------------ * UART the serial port *-----------------------------------------------------------------*/ -#else static nios_uart_t *uart = (nios_uart_t *) CONFIG_SYS_NIOS_CONSOLE; diff --git a/include/nios2-yanu.h b/include/nios2-yanu.h new file mode 100644 index 0000000..1c9a967 --- /dev/null +++ b/include/nios2-yanu.h @@ -0,0 +1,115 @@ +/* + * (C) Copyright 2006, Imagos S.a.s <www.imagos.it> + * Renato Andreola <renato.andreola@imagos.it> + * + * 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 + */ + +/************************************************************************* + * Altera NiosII YANU serial interface by Imagos + * please see http://www.opencores.org/project,yanu for + * information/downloads + ************************************************************************/ + +#ifndef __NIOS2_YANU_H__ +#define __NIOS2_YANU_H__ + +#define YANU_MAX_PRESCALER_N ((1 << 4) - 1) /* 15 */ +#define YANU_MAX_PRESCALER_M ((1 << 11) -1) /* 2047 */ +#define YANU_FIFO_SIZE (16) +#define YANU_RXFIFO_SIZE (YANU_FIFO_SIZE) +#define YANU_TXFIFO_SIZE (YANU_FIFO_SIZE) + +#define YANU_RXFIFO_DLY (10*11) +#define YANU_TXFIFO_THR (10) +#define YANU_DATA_CHAR_MASK (0xFF) + +/* data register */ +#define YANU_DATA_OFFSET (0) /* data register offset */ + +#define YANU_CONTROL_OFFSET (4) /* control register offset */ +/* interrupt enable */ +#define YANU_CONTROL_IE_RRDY (1<<0) /* ie on received character ready */ +#define YANU_CONTROL_IE_OE (1<<1) /* ie on rx overrun */ +#define YANU_CONTROL_IE_BRK (1<<2) /* ie on break detect */ +#define YANU_CONTROL_IE_FE (1<<3) /* ie on framing error */ +#define YANU_CONTROL_IE_PE (1<<4) /* ie on parity error */ +#define YANU_CONTROL_IE_TRDY (1<<5) /* ie interrupt on tranmitter ready */ +/* control bits */ +#define YANU_CONTROL_BITS_POS (6) /* bits number pos */ +#define YANU_CONTROL_BITS (1<<YANU_CONTROL_BITS_POS) /* number of rx/tx bits per word. 3 bit unsigned integer */ +#define YANU_CONTROL_BITS_N (3) /* ... its bit filed length */ +#define YANU_CONTROL_PARENA (1<<9) /* enable parity bit transmission/reception */ +#define YANU_CONTROL_PAREVEN (1<<10) /* parity even */ +#define YANU_CONTROL_STOPS (1<<11) /* number of stop bits */ +#define YANU_CONTROL_HHENA (1<<12) /* Harware Handshake enable... */ +#define YANU_CONTROL_FORCEBRK (1<<13) /* if set than txd = active (0) */ +/* tuning part */ +#define YANU_CONTROL_RDYDLY (1<<14) /* delay from "first" before setting rrdy (in bit) */ +#define YANU_CONTROL_RDYDLY_N (8) /* ... its bit filed length */ +#define YANU_CONTROL_TXTHR (1<<22) /* tx interrupt threshold: the trdy set if txfifo_chars<= txthr (chars) */ +#define YANU_CONTROL_TXTHR_N (4) /* ... its bit field length */ + +#define YANU_BAUD_OFFSET (8) /* baud register offset */ +#define YANU_BAUDM (1<<0) /* baud mantissa lsb */ +#define YANU_BAUDM_N (12) /* ...its bit filed length */ +#define YANU_BAUDE (1<<12) /* baud exponent lsb */ +#define YANU_BAUDE_N (4) /* ...its bit field length */ + +#define YANU_ACTION_OFFSET (12) /* action register... write only */ +#define YANU_ACTION_RRRDY (1<<0) /* reset rrdy */ +#define YANU_ACTION_ROE (1<<1) /* reset oe */ +#define YANU_ACTION_RBRK (1<<2) /* reset brk */ +#define YANU_ACTION_RFE (1<<3) /* reset fe */ +#define YANU_ACTION_RPE (1<<4) /* reset pe */ +#define YANU_ACTION_SRRDY (1<<5) /* set rrdy */ +#define YANU_ACTION_SOE (1<<6) /* set oe */ +#define YANU_ACTION_SBRK (1<<7) /* set brk */ +#define YANU_ACTION_SFE (1<<8) /* set fe */ +#define YANU_ACTION_SPE (1<<9) /* set pe */ +#define YANU_ACTION_RFIFO_PULL (1<<10) /* pull a char from rx fifo we MUST do it before taking a char */ +#define YANU_ACTION_RFIFO_CLEAR (1<<11) /* clear rx fifo */ +#define YANU_ACTION_TFIFO_CLEAR (1<<12) /* clear tx fifo */ +#define YANU_ACTION_RTRDY (1<<13) /* clear trdy */ +#define YANU_ACTION_STRDY (1<<14) /* set trdy */ + +#define YANU_STATUS_OFFSET (16) +#define YANU_STATUS_RRDY (1<<0) /* rxrdy flag */ +#define YANU_STATUS_TRDY (1<<1) /* txrdy flag */ +#define YANU_STATUS_OE (1<<2) /* rx overrun error */ +#define YANU_STATUS_BRK (1<<3) /* rx break detect flag */ +#define YANU_STATUS_FE (1<<4) /* rx framing error flag */ +#define YANU_STATUS_PE (1<<5) /* rx parity erro flag */ +#define YANU_RFIFO_CHARS_POS (6) +#define YANU_RFIFO_CHARS (1<<RFIFO_CHAR_POS) /* number of chars into rx fifo */ +#define YANU_RFIFO_CHARS_N (5) /* ...its bit field length: 32 chars */ +#define YANU_TFIFO_CHARS_POS (11) +#define YANU_TFIFO_CHARS (1<<TFIFO_CHAR_POS) /* number of chars into tx fifo */ +#define YANU_TFIFO_CHARS_N (5) /* ...its bit field length: 32 chars */ + +typedef volatile struct yanu_uart_t { + volatile unsigned data; + volatile unsigned control; /* control register (RW) 32-bit */ + volatile unsigned baud; /* baud/prescaler register (RW) 32-bit */ + volatile unsigned action; /* action register (W) 32-bit */ + volatile unsigned status; /* status register (R) 32-bit */ + volatile unsigned magic; /* magic register (R) 32-bit */ +} yanu_uart_t; + +#endif |