// SPDX-License-Identifier: GPL-2.0+

  /*

   * (C) Copyright 2008 - 2015 Michal Simek <monstr@monstr.eu>

   * Clean driver and add xilinx constant from header file

   *

   * (C) Copyright 2004 Atmark Techno, Inc.

   * Yasushi SHOJI <yashi@atmark-techno.com>

   */
  
  #include <config.h>

  #include <common.h>

  #include <dm.h>

  #include <asm/io.h>

  #include <linux/compiler.h>
  #include <serial.h>

  #define SR_TX_FIFO_FULL		BIT(3) /* transmit FIFO full */
  #define SR_TX_FIFO_EMPTY	BIT(2) /* transmit FIFO empty */
  #define SR_RX_FIFO_VALID_DATA	BIT(0) /* data in receive FIFO */
  #define SR_RX_FIFO_FULL		BIT(1) /* receive FIFO full */

  #define ULITE_CONTROL_RST_TX	0x01
  #define ULITE_CONTROL_RST_RX	0x02

  struct uartlite {
  	unsigned int rx_fifo;
  	unsigned int tx_fifo;
  	unsigned int status;

  	unsigned int control;

  };

  struct uartlite_platdata {
  	struct uartlite *regs;

  };

  static int uartlite_serial_putc(struct udevice *dev, const char ch)

  {

  	struct uartlite_platdata *plat = dev_get_platdata(dev);
  	struct uartlite *regs = plat->regs;

  	if (in_be32(&regs->status) & SR_TX_FIFO_FULL)
  		return -EAGAIN;

  	out_be32(&regs->tx_fifo, ch & 0xff);

  	return 0;

  }

  static int uartlite_serial_getc(struct udevice *dev)

  {

  	struct uartlite_platdata *plat = dev_get_platdata(dev);
  	struct uartlite *regs = plat->regs;
  
  	if (!(in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA))
  		return -EAGAIN;

  	return in_be32(&regs->rx_fifo) & 0xff;
  }

  static int uartlite_serial_pending(struct udevice *dev, bool input)

  {

  	struct uartlite_platdata *plat = dev_get_platdata(dev);
  	struct uartlite *regs = plat->regs;

  	if (input)
  		return in_be32(&regs->status) & SR_RX_FIFO_VALID_DATA;
  
  	return !(in_be32(&regs->status) & SR_TX_FIFO_EMPTY);

  }

  static int uartlite_serial_probe(struct udevice *dev)

  {

  	struct uartlite_platdata *plat = dev_get_platdata(dev);
  	struct uartlite *regs = plat->regs;

  	out_be32(&regs->control, 0);
  	out_be32(&regs->control, ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX);
  	in_be32(&regs->control);

  	return 0;

  }

  static int uartlite_serial_ofdata_to_platdata(struct udevice *dev)

  {

  	struct uartlite_platdata *plat = dev_get_platdata(dev);

  	plat->regs = (struct uartlite *)devfdt_get_addr(dev);

  
  	return 0;

  }

  
  static const struct dm_serial_ops uartlite_serial_ops = {
  	.putc = uartlite_serial_putc,
  	.pending = uartlite_serial_pending,
  	.getc = uartlite_serial_getc,
  };
  
  static const struct udevice_id uartlite_serial_ids[] = {
  	{ .compatible = "xlnx,opb-uartlite-1.00.b", },
  	{ .compatible = "xlnx,xps-uartlite-1.00.a" },
  	{ }
  };
  
  U_BOOT_DRIVER(serial_uartlite) = {
  	.name	= "serial_uartlite",
  	.id	= UCLASS_SERIAL,
  	.of_match = uartlite_serial_ids,
  	.ofdata_to_platdata = uartlite_serial_ofdata_to_platdata,
  	.platdata_auto_alloc_size = sizeof(struct uartlite_platdata),
  	.probe = uartlite_serial_probe,
  	.ops	= &uartlite_serial_ops,

  };

  
  #ifdef CONFIG_DEBUG_UART_UARTLITE
  
  #include <debug_uart.h>
  
  static inline void _debug_uart_init(void)
  {
  	struct uartlite *regs = (struct uartlite *)CONFIG_DEBUG_UART_BASE;
  
  	out_be32(&regs->control, 0);
  	out_be32(&regs->control, ULITE_CONTROL_RST_RX | ULITE_CONTROL_RST_TX);
  	in_be32(&regs->control);
  }
  
  static inline void _debug_uart_putc(int ch)
  {
  	struct uartlite *regs = (struct uartlite *)CONFIG_DEBUG_UART_BASE;
  
  	while (in_be32(&regs->status) & SR_TX_FIFO_FULL)
  		;
  
  	out_be32(&regs->tx_fifo, ch & 0xff);
  }
  
  DEBUG_UART_FUNCS
  #endif