/*-
 * Copyright (c) 2017-2020 Conrad Meyer <cem@FreeBSD.org>
 * 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.
 */

/*
 * Driver for the AMD Family 15h, 17h, 19h, 1Ah CPU System Management Network.
 */

#include <sys/param.h>
#include <sys/bus.h>
#include <sys/conf.h>
#include <sys/lock.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/mutex.h>
#include <sys/sysctl.h>
#include <sys/systm.h>

#include <machine/cpufunc.h>
#include <machine/cputypes.h>
#include <machine/md_var.h>
#include <machine/specialreg.h>

#include <dev/pci/pcivar.h>
#include <x86/pci_cfgreg.h>

#include <dev/amdsmn/amdsmn.h>

#define F15H_SMN_ADDR_REG       0xb8
#define F15H_SMN_DATA_REG       0xbc
#define F17H_SMN_ADDR_REG       0x60
#define F17H_SMN_DATA_REG       0x64

#define PCI_DEVICE_ID_AMD_15H_M60H_ROOT         0x1576
#define PCI_DEVICE_ID_AMD_17H_ROOT              0x1450
#define PCI_DEVICE_ID_AMD_17H_M10H_ROOT         0x15d0
#define PCI_DEVICE_ID_AMD_17H_M30H_ROOT         0x1480  /* Also M70H, F19H M00H/M20H */
#define PCI_DEVICE_ID_AMD_17H_M60H_ROOT         0x1630  /* Also F19H M50H */
#define PCI_DEVICE_ID_AMD_19H_M10H_ROOT         0x14a4
#define PCI_DEVICE_ID_AMD_19H_M40H_ROOT         0x14b5
#define PCI_DEVICE_ID_AMD_19H_M60H_ROOT         0x14d8  /* Also F1AH M40H */
#define PCI_DEVICE_ID_AMD_19H_M70H_ROOT         0x14e8
#define PCI_DEVICE_ID_AMD_1AH_M00H_ROOT         0x153a
#define PCI_DEVICE_ID_AMD_1AH_M20H_ROOT         0x1507
#define PCI_DEVICE_ID_AMD_1AH_M60H_ROOT         0x1122


struct pciid;
struct amdsmn_softc {
        struct mtx smn_lock;
        const struct pciid *smn_pciid;
};

static const struct pciid {
        uint16_t        amdsmn_vendorid;
        uint16_t        amdsmn_deviceid;
        uint8_t         amdsmn_addr_reg;
        uint8_t         amdsmn_data_reg;
} amdsmn_ids[] = {
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_15H_M60H_ROOT,
                .amdsmn_addr_reg = F15H_SMN_ADDR_REG,
                .amdsmn_data_reg = F15H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_17H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_17H_M10H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_17H_M30H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_17H_M60H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_19H_M10H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_19H_M40H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_19H_M60H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_19H_M70H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_1AH_M00H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_1AH_M20H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
        {
                .amdsmn_vendorid = CPU_VENDOR_AMD,
                .amdsmn_deviceid = PCI_DEVICE_ID_AMD_1AH_M60H_ROOT,
                .amdsmn_addr_reg = F17H_SMN_ADDR_REG,
                .amdsmn_data_reg = F17H_SMN_DATA_REG,
        },
};

/*
 * Device methods.
 */
static void     amdsmn_identify(driver_t *driver, device_t parent);
static int      amdsmn_probe(device_t dev);
static int      amdsmn_attach(device_t dev);
static int      amdsmn_detach(device_t dev);

static device_method_t amdsmn_methods[] = {
        /* Device interface */
        DEVMETHOD(device_identify,      amdsmn_identify),
        DEVMETHOD(device_probe,         amdsmn_probe),
        DEVMETHOD(device_attach,        amdsmn_attach),
        DEVMETHOD(device_detach,        amdsmn_detach),
        DEVMETHOD_END
};

static driver_t amdsmn_driver = {
        "amdsmn",
        amdsmn_methods,
        sizeof(struct amdsmn_softc),
};

DRIVER_MODULE(amdsmn, hostb, amdsmn_driver, NULL, NULL);
MODULE_VERSION(amdsmn, 1);
MODULE_PNP_INFO("U16:vendor;U16:device", pci, amdsmn, amdsmn_ids,
    nitems(amdsmn_ids));

static bool
amdsmn_match(device_t parent, const struct pciid **pciid_out)
{
        uint16_t vendor, device;
        size_t i;

        vendor = pci_get_vendor(parent);
        device = pci_get_device(parent);

        for (i = 0; i < nitems(amdsmn_ids); i++) {
                if (vendor == amdsmn_ids[i].amdsmn_vendorid &&
                    device == amdsmn_ids[i].amdsmn_deviceid) {
                        if (pciid_out != NULL)
                                *pciid_out = &amdsmn_ids[i];
                        return (true);
                }
        }
        return (false);
}

static void
amdsmn_identify(driver_t *driver, device_t parent)
{
        device_t child;

        /* Make sure we're not being doubly invoked. */
        if (device_find_child(parent, "amdsmn", DEVICE_UNIT_ANY) != NULL)
                return;
        if (!amdsmn_match(parent, NULL))
                return;

        child = device_add_child(parent, "amdsmn", DEVICE_UNIT_ANY);
        if (child == NULL)
                device_printf(parent, "add amdsmn child failed\n");
}

static int
amdsmn_probe(device_t dev)
{
        uint32_t family;

        if (resource_disabled("amdsmn", 0))
                return (ENXIO);
        if (!amdsmn_match(device_get_parent(dev), NULL))
                return (ENXIO);

        family = CPUID_TO_FAMILY(cpu_id);

        switch (family) {
        case 0x15:
        case 0x17:
        case 0x19:
        case 0x1a:
                break;
        default:
                return (ENXIO);
        }
        device_set_descf(dev, "AMD Family %02Xh System Management Network",
            family);

        return (BUS_PROBE_GENERIC);
}

static int
amdsmn_attach(device_t dev)
{
        struct amdsmn_softc *sc = device_get_softc(dev);

        if (!amdsmn_match(device_get_parent(dev), &sc->smn_pciid))
                return (ENXIO);

        mtx_init(&sc->smn_lock, "SMN mtx", "SMN", MTX_DEF);
        return (0);
}

int
amdsmn_detach(device_t dev)
{
        struct amdsmn_softc *sc = device_get_softc(dev);

        mtx_destroy(&sc->smn_lock);
        return (0);
}

int
amdsmn_read(device_t dev, uint32_t addr, uint32_t *value)
{
        struct amdsmn_softc *sc = device_get_softc(dev);
        device_t parent;

        parent = device_get_parent(dev);

        mtx_lock(&sc->smn_lock);
        pci_write_config(parent, sc->smn_pciid->amdsmn_addr_reg, addr, 4);
        *value = pci_read_config(parent, sc->smn_pciid->amdsmn_data_reg, 4);
        mtx_unlock(&sc->smn_lock);

        return (0);
}

int
amdsmn_write(device_t dev, uint32_t addr, uint32_t value)
{
        struct amdsmn_softc *sc = device_get_softc(dev);
        device_t parent;

        parent = device_get_parent(dev);

        mtx_lock(&sc->smn_lock);
        pci_write_config(parent, sc->smn_pciid->amdsmn_addr_reg, addr, 4);
        pci_write_config(parent, sc->smn_pciid->amdsmn_data_reg, value, 4);
        mtx_unlock(&sc->smn_lock);

        return (0);
}