2 * Copyright (C) 2015 Freescale Semiconductor, Inc.
3 * Copyright (c) 2017, Linaro Limited
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29 #include <drivers/ns16550.h>
34 /* uart register defines */
45 /* uart status register bits */
46 #define UART_LSR_THRE 0x20 /* Transmit-hold-register empty */
48 static vaddr_t chip_to_base(struct serial_chip *chip)
50 struct ns16550_data *pd =
51 container_of(chip, struct ns16550_data, chip);
53 return io_pa_or_va(&pd->base);
56 static void ns16550_flush(struct serial_chip *chip)
58 vaddr_t base = chip_to_base(chip);
60 while ((read8(base + UART_LSR) & UART_LSR_THRE) == 0)
64 static void ns16550_putc(struct serial_chip *chip, int ch)
66 vaddr_t base = chip_to_base(chip);
70 /* write out charset to Transmit-hold-register */
71 write8(ch, base + UART_THR);
74 static const struct serial_ops ns16550_ops = {
75 .flush = ns16550_flush,
78 KEEP_PAGER(ns16550_ops);
80 void ns16550_init(struct ns16550_data *pd, paddr_t base)
83 pd->chip.ops = &ns16550_ops;
86 * Do nothing, uart driver shared with normal world,
87 * everything for uart driver initialization is done in bootloader.