From eae7788c435cfab344c9741c9501475e9ab2797a Mon Sep 17 00:00:00 2001
From: Renato Andreola <renato.andre...@imagos.it>
Date: Mon, 24 Aug 2009 11:10:44 +0200
Subject: [PATCH] Yanu Support for U-Boot
with this patch YANU uart (from opencores) support will be added to u-boot.
Remember to modify properly your board files for defining physical
address etc etc
---
cpu/nios2/serial.c | 170 +++++++++++++++++++++++++++++++++++++++++++++++++-
include/nios2-yanu.h | 122 ++++++++++++++++++++++++++++++++++++
2 files changed, 291 insertions(+), 1 deletions(-)
create mode 100644 include/nios2-yanu.h
diff --git a/cpu/nios2/serial.c b/cpu/nios2/serial.c
index 8bbb803..84be160 100644
--- a/cpu/nios2/serial.c
+++ b/cpu/nios2/serial.c
@@ -26,6 +26,7 @@
#include <watchdog.h>
#include <asm/io.h>
#include <nios2-io.h>
+#include <nios2-yanu.h>
DECLARE_GLOBAL_DATA_PTR;
@@ -74,10 +75,177 @@ 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_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)
+{
+ DECLARE_GLOBAL_DATA_PTR;
+ 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 /* CFG_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..c8c868a
--- /dev/null
+++ b/include/nios2-yanu.h
@@ -0,0 +1,122 @@
+/*
+ * (C) Copyright 2006, Imagos S.a.s <www.imagos.it>
+ * Renato Andreola <renato.andre...@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;
+/* control register (RW) 32-bit */
+ volatile unsigned control;
+/* baud/prescaler register (RW) 32-bit */
+ volatile unsigned baud;
+/* action register (W) 32-bit */
+ volatile unsigned action;
+/* status register (R) 32-bit */
+ volatile unsigned status;
+/* magic register (R) 32-bit */
+ volatile unsigned magic;
+} yanu_uart_t;
+
+#endif
--
1.5.5
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