drivers/serial/serial_omap.c

// SPDX-License-Identifier: GPL-2.0+
/*
 * Texas Instruments' OMAP serial driver
 *
 * Copyright (C) 2018 Texas Instruments Incorporated - http://www.ti.com/
 *	Lokesh Vutla <lokeshvutla@ti.com>
 */

#include <common.h>
#include <debug_uart.h>
#include <dm.h>
#include <dt-structs.h>
#include <ns16550.h>
#include <serial.h>
#include <clk.h>

#ifndef CONFIG_SYS_NS16550_CLK
#define CONFIG_SYS_NS16550_CLK  0
#endif

#ifdef CONFIG_DEBUG_UART_OMAP

#include <debug_uart.h>

static inline void _debug_uart_init(void)
{
	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;
	int baud_divisor;

	baud_divisor = ns16550_calc_divisor(com_port, CONFIG_DEBUG_UART_CLOCK,
					    CONFIG_BAUDRATE);
	serial_dout(&com_port->ier, CONFIG_SYS_NS16550_IER);
	serial_dout(&com_port->mdr1, 0x7);
	serial_dout(&com_port->mcr, UART_MCRVAL);
	serial_dout(&com_port->fcr, UART_FCR_DEFVAL);

	serial_dout(&com_port->lcr, UART_LCR_BKSE | UART_LCRVAL);
	serial_dout(&com_port->dll, baud_divisor & 0xff);
	serial_dout(&com_port->dlm, (baud_divisor >> 8) & 0xff);
	serial_dout(&com_port->lcr, UART_LCRVAL);
	serial_dout(&com_port->mdr1, 0x0);
}

static inline void _debug_uart_putc(int ch)
{
	struct NS16550 *com_port = (struct NS16550 *)CONFIG_DEBUG_UART_BASE;

	while (!(serial_din(&com_port->lsr) & UART_LSR_THRE))
		;
	serial_dout(&com_port->thr, ch);
}

DEBUG_UART_FUNCS

#endif

#if CONFIG_IS_ENABLED(DM_SERIAL)

#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
static int omap_serial_ofdata_to_platdata(struct udevice *dev)
{
	struct ns16550_platdata *plat = dev->platdata;
	fdt_addr_t addr;
	struct clk clk;
	int err;

	/* try Processor Local Bus device first */
	addr = dev_read_addr(dev);
	if (addr == FDT_ADDR_T_NONE)
		return -EINVAL;

	plat->base = (unsigned long)map_physmem(addr, 0, MAP_NOCACHE);

	plat->reg_offset = dev_read_u32_default(dev, "reg-offset", 0);
	plat->reg_shift = 2;

	err = clk_get_by_index(dev, 0, &clk);
	if (!err) {
		err = clk_get_rate(&clk);
		if (!IS_ERR_VALUE(err))
			plat->clock = err;
	} else if (err != -ENOENT && err != -ENODEV && err != -ENOSYS) {
		debug("omap serial failed to get clock\n");
		return err;
	}

	if (!plat->clock)
		plat->clock = dev_read_u32_default(dev, "clock-frequency",
						   CONFIG_SYS_NS16550_CLK);
	if (!plat->clock) {
		debug("omap serial clock not defined\n");
		return -EINVAL;
	}

	plat->fcr = UART_FCR_DEFVAL;

	return 0;
}

static const struct udevice_id omap_serial_ids[] = {
	{ .compatible = "ti,omap2-uart", },
	{ .compatible = "ti,omap3-uart", },
	{ .compatible = "ti,omap4-uart", },
	{ .compatible = "ti,am3352-uart", },
	{ .compatible = "ti,am4372-uart", },
	{ .compatible = "ti,dra742-uart", },
	{ .compatible = "ti,am654-uart", },
	{}
};
#endif /* OF_CONTROL && !OF_PLATDATA */

#if CONFIG_IS_ENABLED(SERIAL_PRESENT)
U_BOOT_DRIVER(omap_serial) = {
	.name	= "omap_serial",
	.id	= UCLASS_SERIAL,
#if CONFIG_IS_ENABLED(OF_CONTROL) && !CONFIG_IS_ENABLED(OF_PLATDATA)
	.of_match = omap_serial_ids,
	.ofdata_to_platdata = omap_serial_ofdata_to_platdata,
	.platdata_auto_alloc_size = sizeof(struct ns16550_platdata),
#endif
	.priv_auto_alloc_size = sizeof(struct NS16550),
	.probe = ns16550_serial_probe,
	.ops	= &ns16550_serial_ops,
#if !CONFIG_IS_ENABLED(OF_CONTROL)
	.flags	= DM_FLAG_PRE_RELOC,
#endif
};
#endif
#endif /* DM_SERIAL */