2 * Copyright (C) 2013 Synopsys, Inc. (www.synopsys.com)
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License version 2 as
6 * published by the Free Software Foundation.
13 DECLARE_GLOBAL_DATA_PTR;
15 struct arc_serial_regs {
26 /* Bit definitions of STATUS register */
27 #define UART_RXEMPTY (1 << 5)
28 #define UART_OVERFLOW_ERR (1 << 1)
29 #define UART_TXEMPTY (1 << 7)
31 struct arc_serial_regs *regs;
33 static void arc_serial_setbrg(void)
38 gd->baudrate = CONFIG_BAUDRATE;
40 arc_console_baud = gd->cpu_clk / (gd->baudrate * 4) - 1;
41 writel(arc_console_baud & 0xff, ®s->baudl);
42 writel((arc_console_baud & 0xff00) >> 8, ®s->baudh);
45 static int arc_serial_init(void)
47 regs = (struct arc_serial_regs *)CONFIG_ARC_UART_BASE;
52 static void arc_serial_putc(const char c)
55 arc_serial_putc('\r');
57 while (!(readl(®s->status) & UART_TXEMPTY))
60 writel(c, ®s->data);
63 static int arc_serial_tstc(void)
65 return !(readl(®s->status) & UART_RXEMPTY);
68 static int arc_serial_getc(void)
70 while (!arc_serial_tstc())
73 /* Check for overflow errors */
74 if (readl(®s->status) & UART_OVERFLOW_ERR)
77 return readl(®s->data) & 0xFF;
80 static void arc_serial_puts(const char *s)
83 arc_serial_putc(*s++);
86 static struct serial_device arc_serial_drv = {
88 .start = arc_serial_init,
90 .setbrg = arc_serial_setbrg,
91 .putc = arc_serial_putc,
92 .puts = arc_serial_puts,
93 .getc = arc_serial_getc,
94 .tstc = arc_serial_tstc,
97 void arc_serial_initialize(void)
99 serial_register(&arc_serial_drv);
102 __weak struct serial_device *default_serial_console(void)
104 return &arc_serial_drv;