blob: d4549176b1e29b8d93732aae4fbe998060d93924 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
|
// SPDX-License-Identifier: GPL-2.0
/*
* 16550 serial console support.
*
* Original copied from <file:arch/ppc/boot/common/ns16550.c>
* (which had no copyright)
* Modifications: 2006 (c) MontaVista Software, Inc.
*
* Modified by: Mark A. Greer <mgreer@mvista.com>
*
* Adapted by:
*
* Copyright (c) 2022 Matthias Schiffer <mschiffer@universe-factory.net>
*/
#include <io.h>
#include <serial.h>
#define UART_DLL 0 /* Out: Divisor Latch Low */
#define UART_DLM 1 /* Out: Divisor Latch High */
#define UART_FCR 2 /* Out: FIFO Control Register */
#define UART_LCR 3 /* Out: Line Control Register */
#define UART_MCR 4 /* Out: Modem Control Register */
#define UART_LSR 5 /* In: Line Status Register */
#define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */
#define UART_LSR_DR 0x01 /* Receiver data ready */
#define UART_MSR 6 /* In: Modem Status Register */
#define UART_SCR 7 /* I/O: Scratch Register */
static uint8_t *const reg_base = (uint8_t *)CONFIG_SERIAL_NS16550_REG_BASE;
static const int reg_shift = CONFIG_SERIAL_NS16550_REG_SHIFT;
void serial_console_putchar(char c)
{
while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_THRE) == 0);
out_8(reg_base, c);
}
int serial_console_getc(void)
{
while ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) == 0);
return in_8(reg_base);
}
int serial_console_tstc(void)
{
return ((in_8(reg_base + (UART_LSR << reg_shift)) & UART_LSR_DR) != 0);
}
void serial_console_init(void)
{
out_8(reg_base + (UART_FCR << reg_shift), 0x06);
}
|
