u-boot/drivers/serial/serial_uniphier.c
Masahiro Yamada 7f368553fc serial: add UniPhier serial driver
The driver for on-chip UART used on Panasonic UniPhier platform.

Signed-off-by: Masahiro Yamada <yamada.m@jp.panasonic.com>
2014-10-05 14:10:09 +09:00

204 lines
4.8 KiB
C

/*
* Copyright (C) 2012-2014 Panasonic Corporation
* Author: Masahiro Yamada <yamada.m@jp.panasonic.com>
*
* Based on serial_ns16550.c
* (C) Copyright 2000
* Rob Taylor, Flying Pig Systems. robt@flyingpig.com.
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <serial.h>
#define UART_REG(x) \
u8 x; \
u8 postpad_##x[3];
/*
* Note: Register map is slightly different from that of 16550.
*/
struct uniphier_serial {
UART_REG(rbr); /* 0x00 */
UART_REG(ier); /* 0x04 */
UART_REG(iir); /* 0x08 */
UART_REG(fcr); /* 0x0c */
u8 mcr; /* 0x10 */
u8 lcr;
u16 __postpad;
UART_REG(lsr); /* 0x14 */
UART_REG(msr); /* 0x18 */
u32 __none1;
u32 __none2;
u16 dlr;
u16 __postpad2;
};
#define thr rbr
/*
* These are the definitions for the Line Control Register
*/
#define UART_LCR_WLS_8 0x03 /* 8 bit character length */
/*
* These are the definitions for the Line Status Register
*/
#define UART_LSR_DR 0x01 /* Data ready */
#define UART_LSR_THRE 0x20 /* Xmit holding register empty */
DECLARE_GLOBAL_DATA_PTR;
static void uniphier_serial_init(struct uniphier_serial *port)
{
const unsigned int mode_x_div = 16;
unsigned int divisor;
writeb(UART_LCR_WLS_8, &port->lcr);
divisor = DIV_ROUND_CLOSEST(CONFIG_SYS_UNIPHIER_UART_CLK,
mode_x_div * gd->baudrate);
writew(divisor, &port->dlr);
}
static void uniphier_serial_setbrg(struct uniphier_serial *port)
{
uniphier_serial_init(port);
}
static int uniphier_serial_tstc(struct uniphier_serial *port)
{
return (readb(&port->lsr) & UART_LSR_DR) != 0;
}
static int uniphier_serial_getc(struct uniphier_serial *port)
{
while (!uniphier_serial_tstc(port))
;
return readb(&port->rbr);
}
static void uniphier_serial_putc(struct uniphier_serial *port, const char c)
{
if (c == '\n')
uniphier_serial_putc(port, '\r');
while (!(readb(&port->lsr) & UART_LSR_THRE))
;
writeb(c, &port->thr);
}
static struct uniphier_serial *serial_ports[4] = {
#ifdef CONFIG_SYS_UNIPHIER_SERIAL_BASE0
(struct uniphier_serial *)CONFIG_SYS_UNIPHIER_SERIAL_BASE0,
#else
NULL,
#endif
#ifdef CONFIG_SYS_UNIPHIER_SERIAL_BASE1
(struct uniphier_serial *)CONFIG_SYS_UNIPHIER_SERIAL_BASE1,
#else
NULL,
#endif
#ifdef CONFIG_SYS_UNIPHIER_SERIAL_BASE2
(struct uniphier_serial *)CONFIG_SYS_UNIPHIER_SERIAL_BASE2,
#else
NULL,
#endif
#ifdef CONFIG_SYS_UNIPHIER_SERIAL_BASE3
(struct uniphier_serial *)CONFIG_SYS_UNIPHIER_SERIAL_BASE3,
#else
NULL,
#endif
};
/* Multi serial device functions */
#define DECLARE_ESERIAL_FUNCTIONS(port) \
static int eserial##port##_init(void) \
{ \
uniphier_serial_init(serial_ports[port]); \
return 0 ; \
} \
static void eserial##port##_setbrg(void) \
{ \
uniphier_serial_setbrg(serial_ports[port]); \
} \
static int eserial##port##_getc(void) \
{ \
return uniphier_serial_getc(serial_ports[port]); \
} \
static int eserial##port##_tstc(void) \
{ \
return uniphier_serial_tstc(serial_ports[port]); \
} \
static void eserial##port##_putc(const char c) \
{ \
uniphier_serial_putc(serial_ports[port], c); \
}
/* Serial device descriptor */
#define INIT_ESERIAL_STRUCTURE(port, __name) { \
.name = __name, \
.start = eserial##port##_init, \
.stop = NULL, \
.setbrg = eserial##port##_setbrg, \
.getc = eserial##port##_getc, \
.tstc = eserial##port##_tstc, \
.putc = eserial##port##_putc, \
.puts = default_serial_puts, \
}
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE0)
DECLARE_ESERIAL_FUNCTIONS(0);
struct serial_device uniphier_serial0_device =
INIT_ESERIAL_STRUCTURE(0, "ttyS0");
#endif
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE1)
DECLARE_ESERIAL_FUNCTIONS(1);
struct serial_device uniphier_serial1_device =
INIT_ESERIAL_STRUCTURE(1, "ttyS1");
#endif
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE2)
DECLARE_ESERIAL_FUNCTIONS(2);
struct serial_device uniphier_serial2_device =
INIT_ESERIAL_STRUCTURE(2, "ttyS2");
#endif
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE3)
DECLARE_ESERIAL_FUNCTIONS(3);
struct serial_device uniphier_serial3_device =
INIT_ESERIAL_STRUCTURE(3, "ttyS3");
#endif
__weak struct serial_device *default_serial_console(void)
{
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE0)
return &uniphier_serial0_device;
#elif defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE1)
return &uniphier_serial1_device;
#elif defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE2)
return &uniphier_serial2_device;
#elif defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE3)
return &uniphier_serial3_device;
#else
#error "No uniphier serial ports configured."
#endif
}
void uniphier_serial_initialize(void)
{
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE0)
serial_register(&uniphier_serial0_device);
#endif
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE1)
serial_register(&uniphier_serial1_device);
#endif
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE2)
serial_register(&uniphier_serial2_device);
#endif
#if defined(CONFIG_SYS_UNIPHIER_SERIAL_BASE3)
serial_register(&uniphier_serial3_device);
#endif
}