/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2013 Neel Natu <neel@freebsd.org>
 * Copyright (c) 2013 Tycho Nightingale <tycho.nightingale@pluribusnetworks.com>
 * 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 NETAPP, INC ``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 NETAPP, INC 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/types.h>

#include <machine/vmm.h>
#include <machine/vmm_snapshot.h>

#include <err.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <vmmapi.h>

#include "acpi.h"
#include "debug.h"
#include "bootrom.h"
#include "config.h"
#include "inout.h"
#include "pci_emul.h"
#include "pci_irq.h"
#include "pci_lpc.h"
#include "pctestdev.h"
#include "tpm_device.h"
#include "uart_emul.h"

#define IO_ICU1         0x20
#define IO_ICU2         0xA0

SET_DECLARE(lpc_dsdt_set, struct lpc_dsdt);
SET_DECLARE(lpc_sysres_set, struct lpc_sysres);

#define ELCR_PORT       0x4d0
SYSRES_IO(ELCR_PORT, 2);

#define IO_TIMER1_PORT  0x40

#define NMISC_PORT      0x61
SYSRES_IO(NMISC_PORT, 1);

static struct pci_devinst *lpc_bridge;

#define LPC_UART_NUM    4
static struct lpc_uart_softc {
        struct uart_ns16550_softc *uart_softc;
        int     iobase;
        int     irq;
        int     enabled;
} lpc_uart_softc[LPC_UART_NUM];

static const char *lpc_uart_names[LPC_UART_NUM] = {
        "com1", "com2", "com3", "com4"
};

static const char *lpc_uart_acpi_names[LPC_UART_NUM] = {
        "COM1", "COM2", "COM3", "COM4"
};

/*
 * LPC device configuration is in the following form:
 * <lpc_device_name>[,<options>]
 * For e.g. "com1,stdio" or "bootrom,/var/romfile"
 */
int
lpc_device_parse(const char *opts)
{
        int unit, error;
        char *str, *cpy, *lpcdev, *node_name;
        const char *romfile, *varfile, *tpm_type, *tpm_path;

        error = -1;
        str = cpy = strdup(opts);
        lpcdev = strsep(&str, ",");
        if (lpcdev != NULL) {
                if (strcasecmp(lpcdev, "bootrom") == 0) {
                        romfile = strsep(&str, ",");
                        if (romfile == NULL) {
                                errx(4, "invalid bootrom option \"%s\"", opts);
                        }
                        set_config_value("bootrom", romfile);

                        varfile = strsep(&str, ",");
                        if (varfile == NULL) {
                                error = 0;
                                goto done;
                        }
                        if (strchr(varfile, '=') == NULL) {
                                set_config_value("bootvars", varfile);
                        } else {
                                /* varfile doesn't exist, it's another config
                                 * option */
                                pci_parse_legacy_config(find_config_node("lpc"),
                                    varfile);
                        }

                        pci_parse_legacy_config(find_config_node("lpc"), str);
                        error = 0;
                        goto done;
                }
                if (strcasecmp(lpcdev, "tpm") == 0) {
                        nvlist_t *nvl = create_config_node("tpm");

                        tpm_type = strsep(&str, ",");
                        if (tpm_type == NULL) {
                                errx(4, "invalid tpm type \"%s\"", opts);
                        }
                        set_config_value_node(nvl, "type", tpm_type);

                        tpm_path = strsep(&str, ",");
                        if (tpm_path == NULL) {
                                errx(4, "invalid tpm path \"%s\"", opts);
                        }
                        set_config_value_node(nvl, "path", tpm_path);

                        pci_parse_legacy_config(find_config_node("tpm"), str);

                        set_config_value_node_if_unset(nvl, "version", "2.0");
                        error = 0;
                        goto done;
                }
                for (unit = 0; unit < LPC_UART_NUM; unit++) {
                        if (strcasecmp(lpcdev, lpc_uart_names[unit]) == 0) {
                                asprintf(&node_name, "lpc.%s.path",
                                    lpc_uart_names[unit]);
                                set_config_value(node_name, str);
                                free(node_name);
                                error = 0;
                                goto done;
                        }
                }
                if (strcasecmp(lpcdev, pctestdev_getname()) == 0) {
                        asprintf(&node_name, "lpc.%s", pctestdev_getname());
                        set_config_bool(node_name, true);
                        free(node_name);
                        error = 0;
                        goto done;
                }
        }

done:
        free(cpy);

        return (error);
}

void
lpc_print_supported_devices(void)
{
        size_t i;

        printf("bootrom\n");
        for (i = 0; i < LPC_UART_NUM; i++)
                printf("%s\n", lpc_uart_names[i]);
        printf("tpm\n");
        printf("%s\n", pctestdev_getname());
}

const char *
lpc_fwcfg(void)
{
        return (get_config_value("lpc.fwcfg"));
}

static void
lpc_uart_intr_assert(void *arg)
{
        struct lpc_uart_softc *sc = arg;

        assert(sc->irq >= 0);

        vm_isa_pulse_irq(lpc_bridge->pi_vmctx, sc->irq, sc->irq);
}

static void
lpc_uart_intr_deassert(void *arg __unused)
{
        /*
         * The COM devices on the LPC bus generate edge triggered interrupts,
         * so nothing more to do here.
         */
}

static int
lpc_uart_io_handler(struct vmctx *ctx __unused, int in,
    int port, int bytes, uint32_t *eax, void *arg)
{
        int offset;
        struct lpc_uart_softc *sc = arg;

        offset = port - sc->iobase;

        switch (bytes) {
        case 1:
                if (in)
                        *eax = uart_ns16550_read(sc->uart_softc, offset);
                else
                        uart_ns16550_write(sc->uart_softc, offset, *eax);
                break;
        case 2:
                if (in) {
                        *eax = uart_ns16550_read(sc->uart_softc, offset);
                        *eax |=
                            uart_ns16550_read(sc->uart_softc, offset + 1) << 8;
                } else {
                        uart_ns16550_write(sc->uart_softc, offset, *eax);
                        uart_ns16550_write(sc->uart_softc, offset + 1,
                            *eax >> 8);
                }
                break;
        default:
                return (-1);
        }

        return (0);
}

static int
lpc_init(struct vmctx *ctx)
{
        struct lpc_uart_softc *sc;
        struct inout_port iop;
        const char *backend, *name;
        char *node_name;
        int unit, error;

        /* COM1 and COM2 */
        for (unit = 0; unit < LPC_UART_NUM; unit++) {
                sc = &lpc_uart_softc[unit];
                name = lpc_uart_names[unit];

                if (uart_legacy_alloc(unit, &sc->iobase, &sc->irq) != 0) {
                        EPRINTLN("Unable to allocate resources for "
                            "LPC device %s", name);
                        return (-1);
                }
                pci_irq_reserve(sc->irq);

                sc->uart_softc = uart_ns16550_init(lpc_uart_intr_assert,
                    lpc_uart_intr_deassert, sc);

                asprintf(&node_name, "lpc.%s.path", name);
                backend = get_config_value(node_name);
                free(node_name);
                if (backend != NULL &&
                    uart_ns16550_tty_open(sc->uart_softc, backend) != 0) {
                        EPRINTLN("Unable to initialize backend '%s' "
                            "for LPC device %s", backend, name);
                        return (-1);
                }

                bzero(&iop, sizeof(struct inout_port));
                iop.name = name;
                iop.port = sc->iobase;
                iop.size = UART_NS16550_IO_BAR_SIZE;
                iop.flags = IOPORT_F_INOUT;
                iop.handler = lpc_uart_io_handler;
                iop.arg = sc;

                error = register_inout(&iop);
                assert(error == 0);
                sc->enabled = 1;
        }

        /* pc-testdev */
        asprintf(&node_name, "lpc.%s", pctestdev_getname());
        if (get_config_bool_default(node_name, false)) {
                error = pctestdev_init(ctx);
                if (error)
                        return (error);
        }
        free(node_name);

        return (0);
}

static void
pci_lpc_write_dsdt(struct pci_devinst *pi)
{
        struct lpc_dsdt **ldpp, *ldp;

        dsdt_line("");
        dsdt_line("Device (ISA)");
        dsdt_line("{");
        dsdt_line("  Name (_ADR, 0x%04X%04X)", pi->pi_slot, pi->pi_func);
        dsdt_line("  OperationRegion (LPCR, PCI_Config, 0x00, 0x100)");
        dsdt_line("  Field (LPCR, AnyAcc, NoLock, Preserve)");
        dsdt_line("  {");
        dsdt_line("    Offset (0x60),");
        dsdt_line("    PIRA,   8,");
        dsdt_line("    PIRB,   8,");
        dsdt_line("    PIRC,   8,");
        dsdt_line("    PIRD,   8,");
        dsdt_line("    Offset (0x68),");
        dsdt_line("    PIRE,   8,");
        dsdt_line("    PIRF,   8,");
        dsdt_line("    PIRG,   8,");
        dsdt_line("    PIRH,   8");
        dsdt_line("  }");
        dsdt_line("");

        dsdt_indent(1);
        SET_FOREACH(ldpp, lpc_dsdt_set) {
                ldp = *ldpp;
                ldp->handler();
        }

        dsdt_line("");
        dsdt_line("Device (PIC)");
        dsdt_line("{");
        dsdt_line("  Name (_HID, EisaId (\"PNP0000\"))");
        dsdt_line("  Name (_CRS, ResourceTemplate ()");
        dsdt_line("  {");
        dsdt_indent(2);
        dsdt_fixed_ioport(IO_ICU1, 2);
        dsdt_fixed_ioport(IO_ICU2, 2);
        dsdt_fixed_irq(2);
        dsdt_unindent(2);
        dsdt_line("  })");
        dsdt_line("}");

        dsdt_line("");
        dsdt_line("Device (TIMR)");
        dsdt_line("{");
        dsdt_line("  Name (_HID, EisaId (\"PNP0100\"))");
        dsdt_line("  Name (_CRS, ResourceTemplate ()");
        dsdt_line("  {");
        dsdt_indent(2);
        dsdt_fixed_ioport(IO_TIMER1_PORT, 4);
        dsdt_fixed_irq(0);
        dsdt_unindent(2);
        dsdt_line("  })");
        dsdt_line("}");
        dsdt_unindent(1);

        dsdt_line("}");
}

static void
pci_lpc_sysres_dsdt(void)
{
        struct lpc_sysres **lspp, *lsp;

        dsdt_line("");
        dsdt_line("Device (SIO)");
        dsdt_line("{");
        dsdt_line("  Name (_HID, EisaId (\"PNP0C02\"))");
        dsdt_line("  Name (_CRS, ResourceTemplate ()");
        dsdt_line("  {");

        dsdt_indent(2);
        SET_FOREACH(lspp, lpc_sysres_set) {
                lsp = *lspp;
                switch (lsp->type) {
                case LPC_SYSRES_IO:
                        dsdt_fixed_ioport(lsp->base, lsp->length);
                        break;
                case LPC_SYSRES_MEM:
                        dsdt_fixed_mem32(lsp->base, lsp->length);
                        break;
                }
        }
        dsdt_unindent(2);

        dsdt_line("  })");
        dsdt_line("}");
}
LPC_DSDT(pci_lpc_sysres_dsdt);

static void
pci_lpc_uart_dsdt(void)
{
        struct lpc_uart_softc *sc;
        int unit;

        for (unit = 0; unit < LPC_UART_NUM; unit++) {
                sc = &lpc_uart_softc[unit];
                if (!sc->enabled)
                        continue;
                dsdt_line("");
                dsdt_line("Device (%s)", lpc_uart_acpi_names[unit]);
                dsdt_line("{");
                dsdt_line("  Name (_HID, EisaId (\"PNP0501\"))");
                dsdt_line("  Name (_UID, %d)", unit + 1);
                dsdt_line("  Name (_CRS, ResourceTemplate ()");
                dsdt_line("  {");
                dsdt_indent(2);
                dsdt_fixed_ioport(sc->iobase, UART_NS16550_IO_BAR_SIZE);
                dsdt_fixed_irq(sc->irq);
                dsdt_unindent(2);
                dsdt_line("  })");
                dsdt_line("}");
        }
}
LPC_DSDT(pci_lpc_uart_dsdt);

static int
pci_lpc_cfgwrite(struct pci_devinst *pi, int coff, int bytes, uint32_t val)
{
        int pirq_pin;

        if (bytes == 1) {
                pirq_pin = 0;
                if (coff >= 0x60 && coff <= 0x63)
                        pirq_pin = coff - 0x60 + 1;
                if (coff >= 0x68 && coff <= 0x6b)
                        pirq_pin = coff - 0x68 + 5;
                if (pirq_pin != 0) {
                        pirq_write(pi->pi_vmctx, pirq_pin, val);
                        pci_set_cfgdata8(pi, coff, pirq_read(pirq_pin));
                        return (0);
                }
        }
        return (-1);
}

static void
pci_lpc_write(struct pci_devinst *pi __unused, int baridx __unused,
    uint64_t offset __unused, int size __unused, uint64_t value __unused)
{
}

static uint64_t
pci_lpc_read(struct pci_devinst *pi __unused, int baridx __unused,
    uint64_t offset __unused, int size __unused)
{
        return (0);
}

#define LPC_DEV         0x7000
#define LPC_VENDOR      0x8086
#define LPC_REVID       0x00
#define LPC_SUBVEND_0   0x0000
#define LPC_SUBDEV_0    0x0000

static int
pci_lpc_get_conf(struct pci_conf *conf)
{
        struct pci_conf_io pcio;
        struct pci_match_conf pmc;
        int pcifd;

        pcifd = open("/dev/pci", O_RDONLY);
        if (pcifd < 0) {
                warn("%s: Unable to open /dev/pci", __func__);
                return (-1);
        }

restart:
        memset(&pcio, 0, sizeof(pcio));
        memset(&pmc, 0, sizeof(pmc));
        pmc.pc_class = PCIC_BRIDGE;
        pmc.flags = PCI_GETCONF_MATCH_CLASS;
        do {
                pcio.pat_buf_len = sizeof(pmc);
                pcio.num_patterns = 1;
                pcio.patterns = &pmc;
                pcio.match_buf_len = sizeof(*conf);
                pcio.matches = conf;
                if (ioctl(pcifd, PCIOCGETCONF, &pcio) == -1) {
                        warn("%s: ioctl(PCIOCGETCONF) failed", __func__);
                        break;
                }
                if (pcio.num_matches == 0)
                        break;
                if (pcio.status == PCI_GETCONF_LIST_CHANGED)
                        goto restart;

                if (conf->pc_class == PCIC_BRIDGE &&
                    conf->pc_subclass == PCIS_BRIDGE_ISA) {
                        close(pcifd);
                        return (0);
                }
        } while (pcio.status == PCI_GETCONF_MORE_DEVS);

        close(pcifd);

        warnx("%s: Unable to find host selector of LPC bridge", __func__);

        return (-1);
}

static int
pci_lpc_init(struct pci_devinst *pi, nvlist_t *nvl)
{
        struct pci_conf conf, *confp;
        uint16_t device, subdevice, subvendor, vendor;
        uint8_t revid;

        /*
         * Do not allow more than one LPC bridge to be configured.
         */
        if (lpc_bridge != NULL) {
                EPRINTLN("Only one LPC bridge is allowed.");
                return (-1);
        }

        /*
         * Enforce that the LPC can only be configured on bus 0. This
         * simplifies the ACPI DSDT because it can provide a decode for
         * all legacy i/o ports behind bus 0.
         */
        if (pi->pi_bus != 0) {
                EPRINTLN("LPC bridge can be present only on bus 0.");
                return (-1);
        }

        if (lpc_init(pi->pi_vmctx) != 0)
                return (-1);

        confp = NULL;
        if (pci_lpc_get_conf(&conf) == 0)
                confp = &conf;

        vendor = pci_config_read_reg(confp, nvl, PCIR_VENDOR, 2, LPC_VENDOR);
        device = pci_config_read_reg(confp, nvl, PCIR_DEVICE, 2, LPC_DEV);
        revid = pci_config_read_reg(confp, nvl, PCIR_REVID, 1, LPC_REVID);
        subvendor = pci_config_read_reg(confp, nvl, PCIR_SUBVEND_0, 2,
            LPC_SUBVEND_0);
        subdevice = pci_config_read_reg(confp, nvl, PCIR_SUBDEV_0, 2,
            LPC_SUBDEV_0);

        /* initialize config space */
        pci_set_cfgdata16(pi, PCIR_VENDOR, vendor);
        pci_set_cfgdata16(pi, PCIR_DEVICE, device);
        pci_set_cfgdata8(pi, PCIR_CLASS, PCIC_BRIDGE);
        pci_set_cfgdata8(pi, PCIR_SUBCLASS, PCIS_BRIDGE_ISA);
        pci_set_cfgdata8(pi, PCIR_REVID, revid);
        pci_set_cfgdata16(pi, PCIR_SUBVEND_0, subvendor);
        pci_set_cfgdata16(pi, PCIR_SUBDEV_0, subdevice);

        lpc_bridge = pi;

        return (0);
}

char *
lpc_pirq_name(int pin)
{
        char *name;

        if (lpc_bridge == NULL)
                return (NULL);
        asprintf(&name, "\\_SB.PC00.ISA.LNK%c,", 'A' + pin - 1);
        return (name);
}

void
lpc_pirq_routed(void)
{
        int pin;

        if (lpc_bridge == NULL)
                return;

        for (pin = 0; pin < 4; pin++)
                pci_set_cfgdata8(lpc_bridge, 0x60 + pin, pirq_read(pin + 1));
        for (pin = 0; pin < 4; pin++)
                pci_set_cfgdata8(lpc_bridge, 0x68 + pin, pirq_read(pin + 5));
}

#ifdef BHYVE_SNAPSHOT
static int
pci_lpc_snapshot(struct vm_snapshot_meta *meta)
{
        int unit, ret;
        struct uart_ns16550_softc *sc;

        for (unit = 0; unit < LPC_UART_NUM; unit++) {
                sc = lpc_uart_softc[unit].uart_softc;

                ret = uart_ns16550_snapshot(sc, meta);
                if (ret != 0)
                        goto done;
        }

done:
        return (ret);
}
#endif

static const struct pci_devemu pci_de_lpc = {
        .pe_emu =       "lpc",
        .pe_init =      pci_lpc_init,
        .pe_write_dsdt = pci_lpc_write_dsdt,
        .pe_cfgwrite =  pci_lpc_cfgwrite,
        .pe_barwrite =  pci_lpc_write,
        .pe_barread =   pci_lpc_read,
#ifdef BHYVE_SNAPSHOT
        .pe_snapshot =  pci_lpc_snapshot,
#endif
};
PCI_EMUL_SET(pci_de_lpc);