/*
 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
 * Copyright (c) 2016 Netflix, Inc
 * 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 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 <sys/cdefs.h>

/*
 * PnP enumerator using the PCI BIOS.
 */

#include <stand.h>
#include <machine/stdarg.h>
#include <machine/cpufunc.h>
#include <bootstrap.h>
#include <isapnp.h>
#include <btxv86.h>
#include "libi386.h"
#include "ficl.h"

/*
 * Stupid PCI BIOS interface doesn't let you simply enumerate everything
 * that's there, instead you have to ask it if it has something.
 *
 * So we have to scan by class code, subclass code and sometimes programming
 * interface.
 */

struct pci_progif
{
        int             pi_code;
        const char      *pi_name;
};

static struct pci_progif progif_null[] = {
        {0x0,   NULL},
        {-1,    NULL}
};

static struct pci_progif progif_display[] = {
        {0x0,   "VGA"},
        {0x1,   "8514"},
        {-1,    NULL}
};

static struct pci_progif progif_ide[] = {
        {0x00,  NULL},
        {0x01,  NULL},
        {0x02,  NULL},
        {0x03,  NULL},
        {0x04,  NULL},
        {0x05,  NULL},
        {0x06,  NULL},
        {0x07,  NULL},
        {0x08,  NULL},
        {0x09,  NULL},
        {0x0a,  NULL},
        {0x0b,  NULL},
        {0x0c,  NULL},
        {0x0d,  NULL},
        {0x0e,  NULL},
        {0x0f,  NULL},
        {0x80,  NULL},
        {0x81,  NULL},
        {0x82,  NULL},
        {0x83,  NULL},
        {0x84,  NULL},
        {0x85,  NULL},
        {0x86,  NULL},
        {0x87,  NULL},
        {0x88,  NULL},
        {0x89,  NULL},
        {0x8a,  NULL},
        {0x8b,  NULL},
        {0x8c,  NULL},
        {0x8d,  NULL},
        {0x8e,  NULL},
        {0x8f,  NULL},
        {-1,    NULL}
};

static struct pci_progif progif_serial[] = {
        {0x0,   "8250"},
        {0x1,   "16450"},
        {0x2,   "16550"},
        {-1,    NULL}
};

static struct pci_progif progif_parallel[] = {
        {0x0,   "Standard"},
        {0x1,   "Bidirectional"},
        {0x2,   "ECP"},
        {-1,    NULL}
};

static struct pci_progif progif_firewire[] = {
        {0x10,  "OHCI"},
        {-1,    NULL}
};

struct pci_subclass
{
        int                     ps_subclass;
        const char              *ps_name;
        /* if set, use for programming interface value(s) */
        struct pci_progif       *ps_progif;
};

static struct pci_subclass subclass_old[] = {
        {0x0,   "Old non-VGA",          progif_null},
        {0x1,   "Old VGA",              progif_null},
        {-1,    NULL,                   NULL}
};

static struct pci_subclass subclass_mass[] = {
        {0x0,   "SCSI",                 progif_null},
        {0x1,   "IDE",                  progif_ide},
        {0x2,   "Floppy disk",          progif_null},
        {0x3,   "IPI",                  progif_null},
        {0x4,   "RAID",                 progif_null},
        {0x80,  "mass storage",         progif_null},
        {-1,    NULL,                   NULL}
};

static struct pci_subclass subclass_net[] = {
        {0x0,   "Ethernet",             progif_null},
        {0x1,   "Token ring",           progif_null},
        {0x2,   "FDDI",                 progif_null},
        {0x3,   "ATM",                  progif_null},
        {0x80,  "network",              progif_null},
        {-1,    NULL,                   NULL}
};

static struct pci_subclass subclass_display[] = {
        {0x0,   NULL,                   progif_display},
        {0x1,   "XGA",                  progif_null},
        {0x80,  "other",                progif_null},
        {-1,    NULL,                   NULL}
};

static struct pci_subclass subclass_comms[] = {
        {0x0,   "serial",               progif_serial},
        {0x1,   "parallel",             progif_parallel},
        {0x80,  "communications",       progif_null},
        {-1,    NULL,                   NULL}
};

static struct pci_subclass subclass_serial[] = {
        {0x0,   "FireWire",             progif_firewire},
        {0x1,   "ACCESS.bus",           progif_null},
        {0x2,   "SSA",                  progif_null},
        {0x3,   "USB",                  progif_null},
        {0x4,   "Fibrechannel",         progif_null},
        {-1,    NULL,                   NULL}
};

static struct pci_class
{
        int                     pc_class;
        const char              *pc_name;
        struct pci_subclass     *pc_subclass;
} pci_classes[] = {
        {0x0,   "device",       subclass_old},
        {0x1,   "controller",   subclass_mass},
        {0x2,   "controller",   subclass_net},
        {0x3,   "display",      subclass_display},
        {0x7,   "controller",   subclass_comms},
        {0xc,   "controller",   subclass_serial},
        {-1,    NULL,           NULL}
};


static void     biospci_enumerate(void);
static void     biospci_addinfo(int, struct pci_class *, struct pci_subclass *,
    struct pci_progif *);

struct pnphandler biospcihandler =
{
        "PCI BIOS",
        biospci_enumerate
};

#define PCI_BIOS_PRESENT        0xb101
#define FIND_PCI_DEVICE         0xb102
#define FIND_PCI_CLASS_CODE     0xb103
#define GENERATE_SPECIAL_CYCLE  0xb106
#define READ_CONFIG_BYTE        0xb108
#define READ_CONFIG_WORD        0xb109
#define READ_CONFIG_DWORD       0xb10a
#define WRITE_CONFIG_BYTE       0xb10b
#define WRITE_CONFIG_WORD       0xb10c
#define WRITE_CONFIG_DWORD      0xb10d
#define GET_IRQ_ROUTING_OPTIONS 0xb10e
#define SET_PCI_IRQ             0xb10f

#define PCI_INT                 0x1a

#define PCI_SIGNATURE           0x20494350      /* AKA "PCI " */

void
biospci_detect(void)
{
        uint16_t version, hwcap, maxbus;
        char buf[24];

        /* Find the PCI BIOS */
        v86.ctl = V86_FLAGS;
        v86.addr = PCI_INT;
        v86.eax = PCI_BIOS_PRESENT;
        v86.edi = 0x0;
        v86int();

        /* Check for OK response */
        if (V86_CY(v86.efl) || ((v86.eax & 0xff00) != 0) ||
            (v86.edx != PCI_SIGNATURE))
                return;

        version = v86.ebx & 0xffff;
        hwcap = v86.eax & 0xff;
        maxbus = v86.ecx & 0xff;
#if 0
        printf("PCI BIOS %d.%d%s%s maxbus %d\n",
            bcd2bin((version >> 8) & 0xf), bcd2bin(version & 0xf),
            (hwcap & 1) ? " config1" : "", (hwcap & 2) ? " config2" : "",
            maxbus);
#endif
        sprintf(buf, "%d", bcd2bin((version >> 8) & 0xf));
        setenv("pcibios.major", buf, 1);
        sprintf(buf, "%d", bcd2bin(version & 0xf));
        setenv("pcibios.minor", buf, 1);
        sprintf(buf, "%d", !!(hwcap & 1));
        setenv("pcibios.config1", buf, 1);
        sprintf(buf, "%d", !!(hwcap & 2));
        setenv("pcibios.config2", buf, 1);
        sprintf(buf, "%d", maxbus);
        setenv("pcibios.maxbus", buf, 1);
}

static void
biospci_enumerate(void)
{
        int                     device_index, err;
        uint32_t                locator, devid;
        struct pci_class        *pc;
        struct pci_subclass     *psc;
        struct pci_progif       *ppi;

        /* Iterate over known classes */
        for (pc = pci_classes; pc->pc_class >= 0; pc++) {
                /* Iterate over subclasses */
                for (psc = pc->pc_subclass; psc->ps_subclass >= 0; psc++) {
                        /* Iterate over programming interfaces */
                        for (ppi = psc->ps_progif; ppi->pi_code >= 0; ppi++) {

                                /* Scan for matches */
                                for (device_index = 0; ; device_index++) {
                                        /* Look for a match */
                                        err = biospci_find_devclass(
                                            (pc->pc_class << 16) +
                                            (psc->ps_subclass << 8) +
                                            ppi->pi_code,
                                            device_index, &locator);
                                        if (err != 0)
                                                break;

                                        /*
                                         * Read the device identifier from
                                         * the nominated device
                                         */
                                        err = biospci_read_config(locator,
                                            0, 2, &devid);
                                        if (err != 0)
                                                break;

                                        /*
                                         * We have the device ID, create a PnP
                                         * object and save everything
                                         */
                                        biospci_addinfo(devid, pc, psc, ppi);
                                }
                        }
                }
        }
}

static void
biospci_addinfo(int devid, struct pci_class *pc, struct pci_subclass *psc,
    struct pci_progif *ppi)
{
        struct pnpinfo  *pi;
        char            desc[80];


        /* build the description */
        desc[0] = 0;
        if (ppi->pi_name != NULL) {
                strcat(desc, ppi->pi_name);
                strcat(desc, " ");
        }
        if (psc->ps_name != NULL) {
                strcat(desc, psc->ps_name);
                strcat(desc, " ");
        }
        if (pc->pc_name != NULL)
                strcat(desc, pc->pc_name);

        pi = pnp_allocinfo();
        pi->pi_desc = strdup(desc);
        sprintf(desc, "0x%08x", devid);
        pnp_addident(pi, desc);
        pnp_addinfo(pi);
}

int
biospci_find_devclass(uint32_t class, int index, uint32_t *locator)
{
        v86.ctl = V86_FLAGS;
        v86.addr = PCI_INT;
        v86.eax = FIND_PCI_CLASS_CODE;
        v86.ecx = class;
        v86.esi = index;
        v86int();

        /* error */
        if (V86_CY(v86.efl) || (v86.eax & 0xff00))
                return (-1);

        *locator = v86.ebx;
        return (0);
}

static int
biospci_find_device(uint32_t devid, int index, uint32_t *locator)
{
        v86.ctl = V86_FLAGS;
        v86.addr = PCI_INT;
        v86.eax = FIND_PCI_DEVICE;
        v86.edx = devid & 0xffff;               /* EDX - Vendor ID */
        v86.ecx = (devid >> 16) & 0xffff;       /* ECX - Device ID */
        v86.esi = index;
        v86int();

        /* error */
        if (V86_CY(v86.efl) || (v86.eax & 0xff00))
                return (-1);

        *locator = v86.ebx;
        return (0);
}
/*
 * Configuration space access methods.
 * width = 0(byte), 1(word) or 2(dword).
 */
int
biospci_write_config(uint32_t locator, int offset, int width, uint32_t val)
{
        v86.ctl = V86_FLAGS;
        v86.addr = PCI_INT;
        v86.eax = WRITE_CONFIG_BYTE + width;
        v86.ebx = locator;
        v86.edi = offset;
        v86.ecx = val;
        v86int();

        /* error */
        if (V86_CY(v86.efl) || (v86.eax & 0xff00))
                return (-1);

        return (0);
}

int
biospci_read_config(uint32_t locator, int offset, int width, uint32_t *val)
{
        v86.ctl = V86_FLAGS;
        v86.addr = PCI_INT;
        v86.eax = READ_CONFIG_BYTE + width;
        v86.ebx = locator;
        v86.edi = offset;
        v86int();

        /* error */
        if (V86_CY(v86.efl) || (v86.eax & 0xff00))
                return (-1);

        *val = v86.ecx;
        return (0);
}

uint32_t
biospci_locator(int8_t bus, uint8_t device, uint8_t function)
{

        return ((bus << 8) | ((device & 0x1f) << 3) | (function & 0x7));
}

/*
 * Counts the number of instances of devid we have in the system, as least as
 * far as the PCI BIOS is able to tell.
 */
static int
biospci_count_device_type(uint32_t devid)
{
        int i;

        for (i = 0; 1; i++) {
                v86.ctl = V86_FLAGS;
                v86.addr = PCI_INT;
                v86.eax = FIND_PCI_DEVICE;
                v86.edx = devid & 0xffff;               /* EDX - Vendor ID */
                v86.ecx = (devid >> 16) & 0xffff;       /* ECX - Device ID */
                v86.esi = i;
                v86int();
                if (V86_CY(v86.efl) || (v86.eax & 0xff00))
                        break;

        }
        return (i);
}

/*
 * pcibios-device-count (devid -- count)
 *
 * Returns the PCI BIOS' count of how many devices matching devid are
 * in the system. devid is the 32-bit vendor + device.
 */
static void
ficlPciBiosCountDevices(ficlVm *pVM)
{
        uint32_t devid;
        int i;

        FICL_STACK_CHECK(ficlVmGetDataStack(pVM), 1, 1);

        devid = ficlStackPopInteger(ficlVmGetDataStack(pVM));

        i = biospci_count_device_type(devid);

        ficlStackPushInteger(ficlVmGetDataStack(pVM), i);
}

/*
 * pcibios-write-config (locator offset width value -- )
 *
 * Writes the specified config register.
 * Locator is bus << 8 | device << 3 | fuction
 * offset is the pci config register
 * width is 0 for byte, 1 for word, 2 for dword
 * value is the value to write
 */
static void
ficlPciBiosWriteConfig(ficlVm *pVM)
{
        uint32_t value, width, offset, locator;

        FICL_STACK_CHECK(ficlVmGetDataStack(pVM), 4, 0);

        value = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        width = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        offset = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        locator = ficlStackPopInteger(ficlVmGetDataStack(pVM));

        biospci_write_config(locator, offset, width, value);
}

/*
 * pcibios-read-config (locator offset width -- value)
 *
 * Reads the specified config register.
 * Locator is bus << 8 | device << 3 | fuction
 * offset is the pci config register
 * width is 0 for byte, 1 for word, 2 for dword
 * value is the value to read from the register
 */
static void
ficlPciBiosReadConfig(ficlVm *pVM)
{
        uint32_t value, width, offset, locator;

        FICL_STACK_CHECK(ficlVmGetDataStack(pVM), 3, 1);

        width = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        offset = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        locator = ficlStackPopInteger(ficlVmGetDataStack(pVM));

        value = 0;
        (void) biospci_read_config(locator, offset, width, &value);

        ficlStackPushInteger(ficlVmGetDataStack(pVM), value);
}

/*
 * pcibios-find-devclass (class index -- locator)
 *
 * Finds the index'th instance of class in the pci tree.
 * must be an exact match.
 * class is the class to search for.
 * index 0..N (set to 0, increment until error)
 *
 * Locator is bus << 8 | device << 3 | fuction (or -1 on error)
 */
static void
ficlPciBiosFindDevclass(ficlVm *pVM)
{
        uint32_t index, class, locator;

        FICL_STACK_CHECK(ficlVmGetDataStack(pVM), 2, 1);

        index = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        class = ficlStackPopInteger(ficlVmGetDataStack(pVM));

        if (biospci_find_devclass(class, index, &locator))
                locator = 0xffffffff;

        ficlStackPushInteger(ficlVmGetDataStack(pVM), locator);
}

/*
 * pcibios-find-device(devid index -- locator)
 *
 * Finds the index'th instance of devid in the pci tree.
 * must be an exact match.
 * class is the class to search for.
 * index 0..N (set to 0, increment until error)
 *
 * Locator is bus << 8 | device << 3 | fuction (or -1 on error)
 */
static void
ficlPciBiosFindDevice(ficlVm *pVM)
{
        uint32_t index, devid, locator;

        FICL_STACK_CHECK(ficlVmGetDataStack(pVM), 2, 1);

        index = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        devid = ficlStackPopInteger(ficlVmGetDataStack(pVM));

        if (biospci_find_device(devid, index, &locator))
                locator = 0xffffffff;

        ficlStackPushInteger(ficlVmGetDataStack(pVM), locator);
}

/*
 * pcibios-locator(bus device function -- locator)
 *
 * converts bus, device, function to locator.
 *
 * Locator is bus << 8 | device << 3 | fuction
 */
static void
ficlPciBiosLocator(ficlVm *pVM)
{
        uint32_t bus, device, function, locator;

        FICL_STACK_CHECK(ficlVmGetDataStack(pVM), 3, 1);

        function = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        device = ficlStackPopInteger(ficlVmGetDataStack(pVM));
        bus = ficlStackPopInteger(ficlVmGetDataStack(pVM));

        locator = biospci_locator(bus, device, function);

        ficlStackPushInteger(ficlVmGetDataStack(pVM), locator);
}

/*
 * Glue function to add the appropriate forth words to access pci bios
 * functionality.
 */
static void
ficlCompilePciBios(ficlSystem *pSys)
{
        ficlDictionary *dp = ficlSystemGetDictionary(pSys);

        FICL_SYSTEM_ASSERT(pSys, dp);

        ficlDictionarySetPrimitive(dp, "pcibios-device-count",
            ficlPciBiosCountDevices, FICL_WORD_DEFAULT);
        ficlDictionarySetPrimitive(dp, "pcibios-read-config",
            ficlPciBiosReadConfig, FICL_WORD_DEFAULT);
        ficlDictionarySetPrimitive(dp, "pcibios-write-config",
            ficlPciBiosWriteConfig, FICL_WORD_DEFAULT);
        ficlDictionarySetPrimitive(dp, "pcibios-find-devclass",
            ficlPciBiosFindDevclass, FICL_WORD_DEFAULT);
        ficlDictionarySetPrimitive(dp, "pcibios-find-device",
            ficlPciBiosFindDevice, FICL_WORD_DEFAULT);
        ficlDictionarySetPrimitive(dp, "pcibios-locator", ficlPciBiosLocator,
            FICL_WORD_DEFAULT);
}

FICL_COMPILE_SET(ficlCompilePciBios);