+++ /dev/null
-/*
- * Altera NiosII YANU serial interface by Imagos
- * please see http://www.opencores.org/project,yanu for
- * information/downloads
- *
- * Copyright 2010, Renato Andreola <renato.andreola@imagos.it>
- *
- * SPDX-License-Identifier: GPL-2.0+
- */
-
-#include <common.h>
-#include <watchdog.h>
-#include <asm/io.h>
-#include <serial.h>
-
-DECLARE_GLOBAL_DATA_PTR;
-
-/*-----------------------------------------------------------------*/
-/* YANU Imagos serial port */
-/*-----------------------------------------------------------------*/
-
-#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 {
- 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;
-
-static yanu_uart_t *uart = (yanu_uart_t *)CONFIG_SYS_NIOS_CONSOLE;
-
-static void oc_serial_setbrg(void)
-{
- int n, k;
- const unsigned max_uns = 0xFFFFFFFF;
- unsigned best_n, best_m, baud;
- unsigned baudrate;
-
-#if defined(CONFIG_SYS_NIOS_FIXEDBAUD)
- /* Everything's already setup for fixed-baud PTF assignment */
- baudrate = CONFIG_BAUDRATE;
-#else
- baudrate = gd->baudrate;
-#endif
- /* 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)) >=
- baudrate) {
- best_n = n;
- break;
- }
- }
- for (k = 0;; k++) {
- if (baudrate <= (max_uns >> (15+n-k)))
- break;
- }
- best_m =
- (baudrate * (1 << (15 + n - k))) /
- ((unsigned)CONFIG_SYS_CLK_FREQ >> k);
-
- baud = best_m + best_n * YANU_BAUDE;
- writel(baud, &uart->baud);
-
- return;
-}
-
-static int oc_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(action, &uart->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(control, &uart->control);
-
- /* to set baud rate */
- serial_setbrg();
-
- return (0);
-}
-
-
-/*-----------------------------------------------------------------------
- * YANU CONSOLE
- *---------------------------------------------------------------------*/
-static void oc_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((unsigned char)c, &uart->data);
-}
-
-static int oc_serial_tstc(void)
-{
- unsigned status ;
-
- status = readl(&uart->status);
- return (((status >> YANU_RFIFO_CHARS_POS) &
- ((1 << YANU_RFIFO_CHARS_N) - 1)) > 0);
-}
-
-static int oc_serial_getc(void)
-{
- while (serial_tstc() == 0)
- WATCHDOG_RESET ();
-
- /* first we pull the char */
- writel(YANU_ACTION_RFIFO_PULL, &uart->action);
-
- return(readl(&uart->data) & YANU_DATA_CHAR_MASK);
-}
-
-static struct serial_device oc_serial_drv = {
- .name = "oc_serial",
- .start = oc_serial_init,
- .stop = NULL,
- .setbrg = oc_serial_setbrg,
- .putc = oc_serial_putc,
- .puts = default_serial_puts,
- .getc = oc_serial_getc,
- .tstc = oc_serial_tstc,
-};
-
-void oc_serial_initialize(void)
-{
- serial_register(&oc_serial_drv);
-}
-
-__weak struct serial_device *default_serial_console(void)
-{
- return &oc_serial_drv;
-}
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