u-boot/drivers/serial/serial_uniphier.c

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/*
* Copyright (C) 2012-2014 Panasonic Corporation
* Author: Masahiro Yamada <yamada.m@jp.panasonic.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <linux/serial_reg.h>
#include <asm/io.h>
#include <asm/errno.h>
#include <dm/device.h>
#include <dm/platform_data/serial-uniphier.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
struct uniphier_serial_private_data {
struct uniphier_serial __iomem *membase;
};
#define uniphier_serial_port(dev) \
((struct uniphier_serial_private_data *)dev_get_priv(dev))->membase
static int uniphier_serial_setbrg(struct udevice *dev, int baudrate)
{
struct uniphier_serial_platform_data *plat = dev_get_platdata(dev);
struct uniphier_serial __iomem *port = uniphier_serial_port(dev);
const unsigned int mode_x_div = 16;
unsigned int divisor;
writeb(UART_LCR_WLEN8, &port->lcr);
divisor = DIV_ROUND_CLOSEST(plat->uartclk, mode_x_div * baudrate);
writew(divisor, &port->dlr);
return 0;
}
static int uniphier_serial_getc(struct udevice *dev)
{
struct uniphier_serial __iomem *port = uniphier_serial_port(dev);
if (!(readb(&port->lsr) & UART_LSR_DR))
return -EAGAIN;
return readb(&port->rbr);
}
static int uniphier_serial_putc(struct udevice *dev, const char c)
{
struct uniphier_serial __iomem *port = uniphier_serial_port(dev);
if (!(readb(&port->lsr) & UART_LSR_THRE))
return -EAGAIN;
writeb(c, &port->thr);
return 0;
}
static int uniphier_serial_pending(struct udevice *dev, bool input)
{
struct uniphier_serial __iomem *port = uniphier_serial_port(dev);
if (input)
return readb(&port->lsr) & UART_LSR_DR;
else
return !(readb(&port->lsr) & UART_LSR_THRE);
}
static int uniphier_serial_probe(struct udevice *dev)
{
struct uniphier_serial_private_data *priv = dev_get_priv(dev);
struct uniphier_serial_platform_data *plat = dev_get_platdata(dev);
priv->membase = map_sysmem(plat->base, sizeof(struct uniphier_serial));
if (!priv->membase)
return -ENOMEM;
return 0;
}
static int uniphier_serial_remove(struct udevice *dev)
{
unmap_sysmem(uniphier_serial_port(dev));
return 0;
}
#ifdef CONFIG_OF_CONTROL
static const struct udevice_id uniphier_uart_of_match = {
{ .compatible = "panasonic,uniphier-uart"},
{},
};
static int uniphier_serial_ofdata_to_platdata(struct udevice *dev)
{
/*
* TODO: Masahiro Yamada (yamada.m@jp.panasonic.com)
*
* Implement conversion code from DTB to platform data
* when supporting CONFIG_OF_CONTROL on UniPhir platform.
*/
}
#endif
static const struct dm_serial_ops uniphier_serial_ops = {
.setbrg = uniphier_serial_setbrg,
.getc = uniphier_serial_getc,
.putc = uniphier_serial_putc,
.pending = uniphier_serial_pending,
};
U_BOOT_DRIVER(uniphier_serial) = {
.name = DRIVER_NAME,
.id = UCLASS_SERIAL,
.of_match = of_match_ptr(uniphier_uart_of_match),
.ofdata_to_platdata = of_match_ptr(uniphier_serial_ofdata_to_platdata),
.probe = uniphier_serial_probe,
.remove = uniphier_serial_remove,
.priv_auto_alloc_size = sizeof(struct uniphier_serial_private_data),
.platdata_auto_alloc_size =
sizeof(struct uniphier_serial_platform_data),
.ops = &uniphier_serial_ops,
.flags = DM_FLAG_PRE_RELOC,
};