/*-
 * Copyright (c) 1998 Michael Smith (msmith@freebsd.org)
 *
 * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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 <stand.h>
#include <bootstrap.h>
#include <machine/cpufunc.h>
#include <dev/ic/ns16550.h>
#include <dev/pci/pcireg.h>
#include "libi386.h"

#define COMC_FMT        0x3             /* 8N1 */
#define COMC_TXWAIT     0x40000         /* transmit timeout */
#define COMC_BPS(x)     (115200 / (x))  /* speed to DLAB divisor */
#define COMC_DIV2BPS(x) (115200 / (x))  /* DLAB divisor to speed */

#ifndef COMPORT
#define COMPORT         0x3f8
#endif
#ifndef COMSPEED
#define COMSPEED        115200
#endif

static void     comc_probe(struct console *cp);
static int      comc_init(int arg);
static void     comc_putchar(int c);
static int      comc_getchar(void);
static int      comc_getspeed(void);
static int      comc_ischar(void);
static int      comc_parseint(const char *string);
static uint32_t comc_parse_pcidev(const char *string);
static int      comc_pcidev_set(struct env_var *ev, int flags,
                    const void *value);
static int      comc_pcidev_handle(uint32_t locator);
static int      comc_port_set(struct env_var *ev, int flags,
                    const void *value);
static void     comc_setup(int speed, int port);
static int      comc_speed_set(struct env_var *ev, int flags,
                    const void *value);

static int      comc_curspeed;
static int      comc_port = COMPORT;
static uint32_t comc_locator;

struct console comconsole = {
        .c_name = "comconsole",
        .c_desc = "serial port",
        .c_flags = 0,
        .c_probe = comc_probe,
        .c_init = comc_init,
        .c_out = comc_putchar,
        .c_in = comc_getchar,
        .c_ready = comc_ischar
};

static void
comc_probe(struct console *cp)
{
        char intbuf[16];
        char *cons, *env;
        int speed, port;
        uint32_t locator;

        if (comc_curspeed == 0) {
                comc_curspeed = COMSPEED;
                /*
                 * Assume that the speed was set by an earlier boot loader if
                 * comconsole is already the preferred console.
                 */
                cons = getenv("console");
                if ((cons != NULL && strcmp(cons, comconsole.c_name) == 0) ||
                    getenv("boot_multicons") != NULL) {
                        comc_curspeed = comc_getspeed();
                }

                env = getenv("comconsole_speed");
                if (env != NULL) {
                        speed = comc_parseint(env);
                        if (speed > 0)
                                comc_curspeed = speed;
                }

                sprintf(intbuf, "%d", comc_curspeed);
                unsetenv("comconsole_speed");
                env_setenv("comconsole_speed", EV_VOLATILE, intbuf,
                    comc_speed_set, env_nounset);

                env = getenv("comconsole_port");
                if (env != NULL) {
                        port = comc_parseint(env);
                        if (port > 0)
                                comc_port = port;
                }

                sprintf(intbuf, "%d", comc_port);
                unsetenv("comconsole_port");
                env_setenv("comconsole_port", EV_VOLATILE, intbuf,
                    comc_port_set, env_nounset);

                env = getenv("comconsole_pcidev");
                if (env != NULL) {
                        locator = comc_parse_pcidev(env);
                        if (locator != 0)
                                comc_pcidev_handle(locator);
                }

                unsetenv("comconsole_pcidev");
                env_setenv("comconsole_pcidev", EV_VOLATILE, env,
                    comc_pcidev_set, env_nounset);
        }
        comc_setup(comc_curspeed, comc_port);
}

static int
comc_init(int arg)
{

        comc_setup(comc_curspeed, comc_port);

        if ((comconsole.c_flags & (C_PRESENTIN | C_PRESENTOUT)) ==
            (C_PRESENTIN | C_PRESENTOUT))
                return (0);
        return (1);
}

static void
comc_putchar(int c)
{
        int wait;

        for (wait = COMC_TXWAIT; wait > 0; wait--)
                if (inb(comc_port + com_lsr) & LSR_TXRDY) {
                        outb(comc_port + com_data, (u_char)c);
                        break;
                }
}

static int
comc_getchar(void)
{
        return (comc_ischar() ? inb(comc_port + com_data) : -1);
}

static int
comc_ischar(void)
{
        return (inb(comc_port + com_lsr) & LSR_RXRDY);
}

static int
comc_speed_set(struct env_var *ev, int flags, const void *value)
{
        int speed;

        if (value == NULL || (speed = comc_parseint(value)) <= 0) {
                printf("Invalid speed\n");
                return (CMD_ERROR);
        }

        if (comc_curspeed != speed)
                comc_setup(speed, comc_port);

        env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);

        return (CMD_OK);
}

static int
comc_port_set(struct env_var *ev, int flags, const void *value)
{
        int port;

        if (value == NULL || (port = comc_parseint(value)) <= 0) {
                printf("Invalid port\n");
                return (CMD_ERROR);
        }

        if (comc_port != port)
                comc_setup(comc_curspeed, port);

        env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);

        return (CMD_OK);
}

/*
 * Input: bus:dev:func[:bar]. If bar is not specified, it is 0x10.
 * Output: bar[24:16] bus[15:8] dev[7:3] func[2:0]
 */
static uint32_t
comc_parse_pcidev(const char *string)
{
#ifdef EFI
        /* We don't support PCI in EFI yet */
        return (0);
#else
        char *p, *p1;
        uint8_t bus, dev, func, bar;
        uint32_t locator;
        int pres;

        pres = strtol(string, &p, 0);
        if (p == string || *p != ':' || pres < 0 )
                return (0);
        bus = pres;
        p1 = ++p;

        pres = strtol(p1, &p, 0);
        if (p == string || *p != ':' || pres < 0 )
                return (0);
        dev = pres;
        p1 = ++p;

        pres = strtol(p1, &p, 0);
        if (p == string || (*p != ':' && *p != '\0') || pres < 0 )
                return (0);
        func = pres;

        if (*p == ':') {
                p1 = ++p;
                pres = strtol(p1, &p, 0);
                if (p == string || *p != '\0' || pres <= 0 )
                        return (0);
                bar = pres;
        } else
                bar = 0x10;

        locator = (bar << 16) | biospci_locator(bus, dev, func);
        return (locator);
#endif
}

static int
comc_pcidev_handle(uint32_t locator)
{
#ifdef EFI
        /* We don't support PCI in EFI yet */
        return (CMD_ERROR);
#else
        char intbuf[64];
        uint32_t port;

        if (biospci_read_config(locator & 0xffff,
            (locator & 0xff0000) >> 16, BIOSPCI_32BITS, &port) == -1) {
                printf("Cannot read bar at 0x%x\n", locator);
                return (CMD_ERROR);
        }

        /* 
         * biospci_read_config() sets port == 0xffffffff if the pcidev
         * isn't found on the bus.  Check for 0xffffffff and return to not
         * panic in BTX.
         */
        if (port == 0xffffffff) {
                printf("Cannot find specified pcidev\n");
                return (CMD_ERROR);
        }
        if (!PCI_BAR_IO(port)) {
                printf("Memory bar at 0x%x\n", locator);
                return (CMD_ERROR);
        }
        port &= PCIM_BAR_IO_BASE;

        sprintf(intbuf, "%d", port);
        unsetenv("comconsole_port");
        env_setenv("comconsole_port", EV_VOLATILE, intbuf,
                   comc_port_set, env_nounset);

        comc_setup(comc_curspeed, port);
        comc_locator = locator;

        return (CMD_OK);
#endif
}

static int
comc_pcidev_set(struct env_var *ev, int flags, const void *value)
{
        uint32_t locator;
        int error;

        if (value == NULL || (locator = comc_parse_pcidev(value)) <= 0) {
                printf("Invalid pcidev\n");
                return (CMD_ERROR);
        }
        if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) != 0 &&
            comc_locator != locator) {
                error = comc_pcidev_handle(locator);
                if (error != CMD_OK)
                        return (error);
        }
        env_setenv(ev->ev_name, flags | EV_NOHOOK, value, NULL, NULL);
        return (CMD_OK);
}

static void
comc_setup(int speed, int port)
{
        static int TRY_COUNT = 1000000;
        char intbuf[64];
        int tries;

        comc_curspeed = speed;
        comc_port = port;
        if ((comconsole.c_flags & (C_ACTIVEIN | C_ACTIVEOUT)) == 0)
                return;

        unsetenv("hw.uart.console");

#define COMC_TEST       0xbb
        /*
         * Write byte to scratch register and read it out.
         */
        outb(comc_port + com_scr, COMC_TEST);
        if (inb(comc_port + com_scr) != COMC_TEST) {
                comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
                return;
        }

        outb(comc_port + com_cfcr, CFCR_DLAB | COMC_FMT);
        outb(comc_port + com_dlbl, COMC_BPS(speed) & 0xff);
        outb(comc_port + com_dlbh, COMC_BPS(speed) >> 8);
        outb(comc_port + com_cfcr, COMC_FMT);
        outb(comc_port + com_mcr, MCR_RTS | MCR_DTR);

        tries = 0;
        do
                inb(comc_port + com_data);
        while (inb(comc_port + com_lsr) & LSR_RXRDY && ++tries < TRY_COUNT);

        if (tries < TRY_COUNT) {
                comconsole.c_flags |= (C_PRESENTIN | C_PRESENTOUT);
                sprintf(intbuf, "io:%d,br:%d", comc_port, comc_curspeed);
                env_setenv("hw.uart.console", EV_VOLATILE, intbuf, NULL, NULL);
        } else
                comconsole.c_flags &= ~(C_PRESENTIN | C_PRESENTOUT);
}

static int
comc_parseint(const char *speedstr)
{
        char *p;
        int speed;

        speed = strtol(speedstr, &p, 0);
        if (p == speedstr || *p != '\0' || speed <= 0)
                return (-1);

        return (speed);
}

static int
comc_getspeed(void)
{
        u_int   divisor;
        u_char  dlbh;
        u_char  dlbl;
        u_char  cfcr;

        cfcr = inb(comc_port + com_cfcr);
        outb(comc_port + com_cfcr, CFCR_DLAB | cfcr);

        dlbl = inb(comc_port + com_dlbl);
        dlbh = inb(comc_port + com_dlbh);

        outb(comc_port + com_cfcr, cfcr);

        divisor = dlbh << 8 | dlbl;

        /* XXX there should be more sanity checking. */
        if (divisor == 0)
                return (COMSPEED);
        return (COMC_DIV2BPS(divisor));
}