serial.h

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/* ASB2305-specific 8250 serial ports
 *
 * Copyright (C) 2007 Red Hat, Inc. All Rights Reserved.
 * Written by David Howells ([email protected])
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public Licence
 * as published by the Free Software Foundation; either version
 * 2 of the Licence, or (at your option) any later version.
 */
#ifndef _ASM_UNIT_SERIAL_H
#define _ASM_UNIT_SERIAL_H

#include <asm/cpu-regs.h>
#include <proc/irq.h>
#include <linux/serial_reg.h>

#define SERIAL_PORT0_BASE_ADDRESS   0xA6FB0000
#define ASB2305_DEBUG_MCR   __SYSREG(0xA6FB0000 + UART_MCR * 2, u8)

#define SERIAL_IRQ  XIRQ0   /* Dual serial (PC16552)    (Hi) */

/*
 * The ASB2305 has an 18.432 MHz clock the UART
 */
#define BASE_BAUD   (18432000 / 16)

/*
 * dispose of the /dev/ttyS0 serial port
 */
#ifndef CONFIG_GDBSTUB_ON_TTYSx

#define SERIAL_PORT_DFNS                        \
    {                               \
    .baud_base      = BASE_BAUD,                \
    .irq            = SERIAL_IRQ,               \
    .flags          = STD_COM_FLAGS,            \
    .iomem_base     = (u8 *) SERIAL_PORT0_BASE_ADDRESS, \
    .iomem_reg_shift    = 2,                    \
    .io_type        = SERIAL_IO_MEM,            \
    },

#ifndef __ASSEMBLY__

static inline void __debug_to_serial(const char *p, int n)
{
}

#endif /* !__ASSEMBLY__ */

#else /* CONFIG_GDBSTUB_ON_TTYSx */

#define SERIAL_PORT_DFNS /* stolen by gdb-stub */

#if defined(CONFIG_GDBSTUB_ON_TTYS0)
#define GDBPORT_SERIAL_RX   __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_RX  * 4, u8)
#define GDBPORT_SERIAL_TX   __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_TX  * 4, u8)
#define GDBPORT_SERIAL_DLL  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_DLL * 4, u8)
#define GDBPORT_SERIAL_DLM  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_DLM * 4, u8)
#define GDBPORT_SERIAL_IER  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_IER * 4, u8)
#define GDBPORT_SERIAL_IIR  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_IIR * 4, u8)
#define GDBPORT_SERIAL_FCR  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_FCR * 4, u8)
#define GDBPORT_SERIAL_LCR  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_LCR * 4, u8)
#define GDBPORT_SERIAL_MCR  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_MCR * 4, u8)
#define GDBPORT_SERIAL_LSR  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_LSR * 4, u8)
#define GDBPORT_SERIAL_MSR  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_MSR * 4, u8)
#define GDBPORT_SERIAL_SCR  __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_SCR * 4, u8)
#define GDBPORT_SERIAL_IRQ  SERIAL_IRQ

#elif defined(CONFIG_GDBSTUB_ON_TTYS1)
#error The ASB2305 doesnt have a /dev/ttyS1
#endif

#ifndef __ASSEMBLY__

#define TTYS0_TX    __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_TX  * 4, u8)
#define TTYS0_MCR   __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_MCR * 4, u8)
#define TTYS0_LSR   __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_LSR * 4, u8)
#define TTYS0_MSR   __SYSREG(SERIAL_PORT0_BASE_ADDRESS + UART_MSR * 4, u8)

#define LSR_WAIT_FOR(STATE)             \
do {                            \
    while (!(TTYS0_LSR & UART_LSR_##STATE)) {}  \
} while (0)
#define FLOWCTL_WAIT_FOR(LINE)              \
do {                            \
    while (!(TTYS0_MSR & UART_MSR_##LINE)) {}   \
} while (0)
#define FLOWCTL_CLEAR(LINE)         \
do {                        \
    TTYS0_MCR &= ~UART_MCR_##LINE;      \
} while (0)
#define FLOWCTL_SET(LINE)           \
do {                        \
    TTYS0_MCR |= UART_MCR_##LINE;       \
} while (0)
#define FLOWCTL_QUERY(LINE) ({ TTYS0_MSR & UART_MSR_##LINE; })

static inline void __debug_to_serial(const char *p, int n)
{
    char ch;

    FLOWCTL_SET(DTR);

    for (; n > 0; n--) {
        LSR_WAIT_FOR(THRE);
        FLOWCTL_WAIT_FOR(CTS);

        ch = *p++;
        if (ch == 0x0a) {
            TTYS0_TX = 0x0d;
            LSR_WAIT_FOR(THRE);
            FLOWCTL_WAIT_FOR(CTS);
        }
        TTYS0_TX = ch;
    }

    FLOWCTL_CLEAR(DTR);
}

#endif /* !__ASSEMBLY__ */

#endif /* CONFIG_GDBSTUB_ON_TTYSx */

#endif /* _ASM_UNIT_SERIAL_H */