u-boot/drivers/serial/serial_s5p4418_pl011.c
Stefan Bosch 5ec6cbcc7f arm: s5p4418: dm_serial: add driver source code
Add dm_serial driver source code for S5P4418 SOC. Extend the "arm,pl011"
driver by init of UART-clock and UART-reset.

Signed-off-by: Stefan Bosch <stefan_b@posteo.net>
2023-01-02 16:06:08 -05:00

94 lines
2.3 KiB
C

// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2022 Stefan Bosch <stefan_b@posteo.net>
*/
#include <common.h>
#include <dm.h>
#include <asm/arch/clk.h>
#include <asm/arch/reset.h>
#include <linux/delay.h>
#include <dm/platform_data/serial_pl01x.h>
#include <serial.h>
#include "serial_pl01x_internal.h"
int s5p4418_pl011_serial_probe(struct udevice *dev)
{
struct pl01x_serial_plat *plat = dev_get_plat(dev);
struct clk *nx_clk;
ulong rate_act;
char uart_clk_name[10];
int uart_num = -1;
int rst_id, ret;
if (!plat->skip_init) {
uart_num = dev->seq_;
rst_id = RESET_ID_UART0 + uart_num;
if (uart_num < 0 || rst_id > RESET_ID_UART5) {
/* invalid UART-number */
debug("%s: sequence/uart number %d is invalid!\n", __func__, uart_num);
return -ENODEV;
}
sprintf(uart_clk_name, "nx-uart.%d", uart_num);
nx_clk = clk_get(uart_clk_name);
if (!nx_clk) {
debug("%s: clk_get('%s') failed!\n", __func__, uart_clk_name);
return -ENODEV;
}
/* wait to make sure all pending characters have been sent */
mdelay(100);
}
/*
* Note: Unless !plat->skip_init, the UART is disabled here, so printf()
* or debug() must not be used until pl01x_serial_setbrg() has been called
* (enables the UART). Otherwise u-boot is hanging!
*/
ret = pl01x_serial_probe(dev);
if (ret)
return ret;
if (!plat->skip_init) {
/* do reset UART */
nx_rstcon_setrst(rst_id, RSTCON_ASSERT);
udelay(10);
nx_rstcon_setrst(rst_id, RSTCON_NEGATE);
udelay(10);
clk_disable(nx_clk);
rate_act = clk_set_rate(nx_clk, plat->clock);
clk_enable(nx_clk);
plat->clock = rate_act;
}
return 0;
}
static const struct dm_serial_ops s5p4418_pl011_serial_ops = {
.putc = pl01x_serial_putc,
.pending = pl01x_serial_pending,
.getc = pl01x_serial_getc,
.setbrg = pl01x_serial_setbrg,
};
static const struct udevice_id s5p4418_pl011_serial_id[] = {
{.compatible = "nexell,s5p4418-pl011", .data = TYPE_PL011},
{}
};
U_BOOT_DRIVER(s5p4418_pl011_uart) = {
.name = "s5p4418_pl011",
.id = UCLASS_SERIAL,
.of_match = of_match_ptr(s5p4418_pl011_serial_id),
.of_to_plat = of_match_ptr(pl01x_serial_of_to_plat),
.plat_auto = sizeof(struct pl01x_serial_plat),
.probe = s5p4418_pl011_serial_probe,
.ops = &s5p4418_pl011_serial_ops,
.flags = DM_FLAG_PRE_RELOC,
.priv_auto = sizeof(struct pl01x_priv),
};