root/sys/dev/uart/uart_cpu_powerpc.c
/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2006 Marcel Moolenaar
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <vm/vm.h>
#include <vm/pmap.h>

#include <machine/bus.h>
#include <machine/ofw_machdep.h>

#include <dev/ofw/ofw_bus_subr.h>
#include <dev/ofw/openfirm.h>
#include <dev/uart/uart.h>
#include <dev/uart/uart_cpu.h>

bus_space_tag_t uart_bus_space_io = &bs_le_tag;
bus_space_tag_t uart_bus_space_mem = &bs_le_tag;

int
uart_cpu_eqres(struct uart_bas *b1, struct uart_bas *b2)
{

        return ((pmap_kextract(b1->bsh) == pmap_kextract(b2->bsh)) ? 1 : 0);
}

static int
ofw_get_uart_console(phandle_t opts, phandle_t *result, const char *inputdev,
    const char *outputdev)
{
        char buf[64];
        phandle_t input;

        if (OF_getprop(opts, inputdev, buf, sizeof(buf)) == -1)
                return (ENXIO);
        input = OF_finddevice(buf);
        if (input == -1)
                return (ENXIO);

        if (outputdev != NULL) {
                if (OF_getprop(opts, outputdev, buf, sizeof(buf)) == -1)
                        return (ENXIO);
                if (OF_finddevice(buf) != input)
                        return (ENXIO);
        }

        *result = input;
        return (0);
}

static int
ofw_get_console_phandle_path(phandle_t node, phandle_t *result,
    const char *prop)
{
        union {
                char buf[64];
                phandle_t ref;
        } field;
        phandle_t output;
        ssize_t size;

        size = OF_getproplen(node, prop);
        if (size == -1)
                return (ENXIO);
        OF_getprop(node, prop, &field, sizeof(field));

        /* This property might be either a ihandle or path. Hooray. */

        output = -1;
        if (field.buf[size - 1] == 0)
                output = OF_finddevice(field.buf);
        if (output == -1 && size == 4)
                output = OF_instance_to_package(field.ref);

        if (output != -1) {
                *result = output;
                return (0);
        }

        return (ENXIO);
}

int
uart_cpu_getdev(int devtype, struct uart_devinfo *di)
{
        char buf[64];
        struct uart_class *class;
        phandle_t input, opts, chosen;
        int error;

        opts = OF_finddevice("/options");
        chosen = OF_finddevice("/chosen");
        switch (devtype) {
        case UART_DEV_CONSOLE:
                error = ENXIO;
                if (chosen != -1 && error != 0)
                        error = ofw_get_uart_console(chosen, &input,
                            "stdout-path", NULL);
                if (chosen != -1 && error != 0)
                        error = ofw_get_uart_console(chosen, &input,
                            "linux,stdout-path", NULL);
                if (chosen != -1 && error != 0)
                        error = ofw_get_console_phandle_path(chosen, &input,
                            "stdout");
                if (chosen != -1 && error != 0)
                        error = ofw_get_uart_console(chosen, &input,
                            "stdin-path", NULL);
                if (chosen != -1 && error != 0)
                        error = ofw_get_console_phandle_path(chosen, &input,
                            "stdin");
                if (opts != -1 && error != 0)
                        error = ofw_get_uart_console(opts, &input,
                            "input-device", "output-device");
                if (opts != -1 && error != 0)
                        error = ofw_get_uart_console(opts, &input,
                            "input-device-1", "output-device-1");
                if (error != 0) {
                        input = OF_finddevice("serial0"); /* Last ditch */
                        if (input == -1)
                                error = (ENXIO);
                }

                if (error != 0)
                        return (error);
                break;
        case UART_DEV_DBGPORT:
                if (!getenv_string("hw.uart.dbgport", buf, sizeof(buf)))
                        return (ENXIO);
                input = OF_finddevice(buf);
                if (input == -1)
                        return (ENXIO);
                break;
        default:
                return (EINVAL);
        }

        if (OF_getprop(input, "device_type", buf, sizeof(buf)) == -1)
                return (ENXIO);
        if (strcmp(buf, "serial") != 0)
                return (ENXIO);

        if (ofw_bus_node_is_compatible(input, "chrp,es")) {
                class = &uart_z8530_class;
                di->bas.regshft = 4;
                di->bas.chan = 1;
        } else if (ofw_bus_node_is_compatible(input,"ns16550") ||
            ofw_bus_node_is_compatible(input,"ns8250")) {
                class = &uart_ns8250_class;
                di->bas.regshft = 0;
                di->bas.chan = 0;
        } else
                return (ENXIO);

        if (class == NULL)
                return (ENXIO);

        error = OF_decode_addr(input, 0, &di->bas.bst, &di->bas.bsh, NULL);
        if (error)
                return (error);

        di->ops = uart_getops(class);

        if (OF_getprop(input, "clock-frequency", &di->bas.rclk, 
            sizeof(di->bas.rclk)) == -1)
                di->bas.rclk = 230400;
        if (OF_getprop(input, "current-speed", &di->baudrate, 
            sizeof(di->baudrate)) == -1)
                di->baudrate = 0;
        OF_getprop(input, "reg-shift", &di->bas.regshft,
            sizeof(di->bas.regshft));

        di->databits = 8;
        di->stopbits = 1;
        di->parity = UART_PARITY_NONE;
        return (0);
}