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// SPDX-License-Identifier: BSD-2-Clause
/*
* Copyright (c) 2020 Carlo Caione <ccaione@baylibre.com>
*/
#include <assert.h>
#include <drivers/amlogic_uart.h>
#include <io.h>
#include <keep.h>
#include <util.h>
/* Registers */
#define AML_UART_WFIFO 0x0000
#define AML_UART_RFIFO 0x0004
#define AML_UART_CONTROL 0x0008
#define AML_UART_STATUS 0x000C
#define AML_UART_MISC 0x0010
/* AML_UART_STATUS bits */
#define AML_UART_RX_EMPTY BIT(20)
#define AML_UART_TX_FULL BIT(21)
#define AML_UART_TX_EMPTY BIT(22)
static vaddr_t chip_to_base(struct serial_chip *chip)
{
struct amlogic_uart_data *pd =
container_of(chip, struct amlogic_uart_data, chip);
return io_pa_or_va(&pd->base);
}
static void amlogic_uart_flush(struct serial_chip *chip)
{
vaddr_t base = chip_to_base(chip);
while (!(io_read32(base + AML_UART_STATUS) & AML_UART_TX_EMPTY))
;
}
static int amlogic_uart_getchar(struct serial_chip *chip)
{
vaddr_t base = chip_to_base(chip);
if (io_read32(base + AML_UART_STATUS) & AML_UART_RX_EMPTY)
return -1;
return io_read32(base + AML_UART_RFIFO) & 0xff;
}
static void amlogic_uart_putc(struct serial_chip *chip, int ch)
{
vaddr_t base = chip_to_base(chip);
while (io_read32(base + AML_UART_STATUS) & AML_UART_TX_FULL)
;
io_write32(base + AML_UART_WFIFO, ch);
}
static const struct serial_ops amlogic_uart_ops = {
.flush = amlogic_uart_flush,
.getchar = amlogic_uart_getchar,
.putc = amlogic_uart_putc,
};
void amlogic_uart_init(struct amlogic_uart_data *pd, paddr_t base)
{
pd->base.pa = base;
pd->chip.ops = &amlogic_uart_ops;
/*
* Do nothing, debug uart (AO) shared with normal world, everything for
* uart initialization is done in bootloader.
*/
}
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