/* -
 *   BSD LICENSE
 * 
 *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
 *   All rights reserved.
 * 
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 * 
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * 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.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 * 
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT
 *   OWNER 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>
__FBSDID("$FreeBSD$");

#include <sys/param.h> /* defines used in kernel.h */
#include <sys/module.h>
#include <sys/kernel.h> /* types used in module initialization */
#include <sys/conf.h> /* cdevsw struct */
#include <sys/bus.h> /* structs, prototypes for pci bus stuff and DEVMETHOD */
#include <sys/rman.h>
#include <sys/systm.h>
#include <sys/proc.h>

#include <machine/bus.h>
#include <dev/pci/pcivar.h> /* For pci_get macros! */
#include <dev/pci/pcireg.h> /* The softc holds our per-instance data. */
#include <vm/vm.h>
#include <vm/uma.h>
#include <vm/vm_object.h>
#include <vm/vm_page.h>
#include <vm/vm_pager.h>

#define MAX_BARS (PCIR_MAX_BAR_0 + 1)


struct nic_uio_softc {
	device_t        dev_t;
	struct cdev     *my_cdev;
	int              bar_id[MAX_BARS];
	struct resource *bar_res[MAX_BARS];
	u_long           bar_start[MAX_BARS];
	u_long           bar_size[MAX_BARS];
};

/* Function prototypes */
static d_open_t         nic_uio_open;
static d_close_t        nic_uio_close;
static d_mmap_t         nic_uio_mmap;
static d_mmap_single_t  nic_uio_mmap_single;
static int              nic_uio_probe(device_t dev);
static int              nic_uio_attach(device_t dev);
static int              nic_uio_detach(device_t dev);
static int              nic_uio_shutdown(void);
static int              nic_uio_modevent(module_t mod, int type, void *arg);

static struct cdevsw uio_cdevsw = {
		.d_name        = "nic_uio",
		.d_version     = D_VERSION,
		.d_open        = nic_uio_open,
		.d_close       = nic_uio_close,
		.d_mmap        = nic_uio_mmap,
		.d_mmap_single = nic_uio_mmap_single,
};

static device_method_t nic_uio_methods[] = {
	DEVMETHOD(device_probe,    nic_uio_probe),
	DEVMETHOD(device_attach,   nic_uio_attach),
	DEVMETHOD(device_detach,   nic_uio_detach),
	DEVMETHOD_END
};

struct device {
    int vend;
    int dev;
};

struct pci_bdf {
	uint32_t bus;
	uint32_t devid;
	uint32_t function;
};


#define RTE_PCI_DEV_ID_DECL_EM(vend, dev)      {vend, dev},
#define RTE_PCI_DEV_ID_DECL_IGB(vend, dev)     {vend, dev},
#define RTE_PCI_DEV_ID_DECL_IGBVF(vend, dev)   {vend, dev},
#define RTE_PCI_DEV_ID_DECL_IXGBE(vend, dev)   {vend, dev},
#define RTE_PCI_DEV_ID_DECL_IXGBEVF(vend, dev) {vend, dev},
#define RTE_PCI_DEV_ID_DECL_VIRTIO(vend, dev)  {vend, dev},

const struct device devices[] = {
#include <rte_pci_dev_ids.h>
};
#define NUM_DEVICES (sizeof(devices)/sizeof(devices[0]))


static devclass_t nic_uio_devclass;

DEFINE_CLASS_0(nic_uio, nic_uio_driver, nic_uio_methods, sizeof(struct nic_uio_softc));
DRIVER_MODULE(nic_uio, pci, nic_uio_driver, nic_uio_devclass, nic_uio_modevent, 0);

static char bdf_str[1024];

static int
nic_uio_mmap(struct cdev *cdev, vm_ooffset_t offset, vm_paddr_t *paddr,
		int prot, vm_memattr_t *memattr)
{
	*paddr = offset;
	return (0);
}

static int
nic_uio_mmap_single(struct cdev *cdev, vm_ooffset_t *offset, vm_size_t size,
		struct vm_object **obj, int nprot)
{
	/*
	 * The BAR index is encoded in the offset.  Divide the offset by
	 *  PAGE_SIZE to get the index of the bar requested by the user
	 *  app.
	 */
	unsigned bar = *offset/PAGE_SIZE;
	struct nic_uio_softc *sc = cdev->si_drv1;

	if (bar >= MAX_BARS)
		return EINVAL;

	if (sc->bar_res[bar] == NULL) {
		sc->bar_id[bar] = PCIR_BAR(bar);

		if (PCI_BAR_IO(pci_read_config(sc->dev_t, sc->bar_id[bar], 4)))
			sc->bar_res[bar] = bus_alloc_resource_any(sc->dev_t, SYS_RES_IOPORT,
					&sc->bar_id[bar], RF_ACTIVE);
		else
			sc->bar_res[bar] = bus_alloc_resource_any(sc->dev_t, SYS_RES_MEMORY,
					&sc->bar_id[bar], RF_ACTIVE);
	}
	if (sc->bar_res[bar] == NULL)
		return ENXIO;

	sc->bar_start[bar] = rman_get_start(sc->bar_res[bar]);
	sc->bar_size[bar] = rman_get_size(sc->bar_res[bar]);

	device_printf(sc->dev_t, "Bar %u @ %lx, size %lx\n", bar,
			sc->bar_start[bar], sc->bar_size[bar]);

	*offset = sc->bar_start[bar];
	*obj = vm_pager_allocate(OBJT_DEVICE, cdev, size, nprot, *offset,
				curthread->td_ucred);
	return 0;
}


int
nic_uio_open(struct cdev *dev, int oflags, int devtype, d_thread_t *td)
{
	return 0;
}

int
nic_uio_close(struct cdev *dev, int fflag, int devtype, d_thread_t *td)
{
	return 0;
}

static int
nic_uio_probe (device_t dev)
{
        int i, len;
        char *remaining;
        long bus = 0, device = 0, function = 0;
        remaining = bdf_str;
        len = strlen(remaining);

        for (i = 0; remaining && len >= 5 && i < len;i+=6) {
                if ( remaining[i + 1] == ':' && remaining[i + 3] == ':' ) {
                        bus = strtol(&remaining[i + 0],NULL,0);
                        device = strtol(&remaining[i + 2],NULL,0);
                        function = strtol(&remaining[i + 4],NULL,0);
                        if (dev != NULL) {
                                if (pci_get_bus(dev) == bus && pci_get_slot(dev) == device && pci_get_function(dev) == function) {
				        for (i = 0; i < NUM_DEVICES; i++) {
				                if (pci_get_vendor(dev) == devices[i].vend && pci_get_device(dev) == devices[i].dev) {
							printf("nic_uio: success probing the wanted device : %ld:%ld:%ld!\n", bus, device, function);
				                        device_set_desc(dev, "Intel(R) DPDK PCI Device");
				                        return (BUS_PROBE_SPECIFIC);
				                }
					}
                                }
                        }
                }
        }

	return (ENXIO);
}

static int
nic_uio_attach(device_t dev)
{
	int i;
	struct nic_uio_softc *sc;

	sc = device_get_softc(dev);
	sc->dev_t = dev;
	sc->my_cdev = make_dev(&uio_cdevsw, device_get_unit(dev),
			UID_ROOT, GID_WHEEL, 0600, "uio@pci:%u:%u:%u",
			pci_get_bus(dev), pci_get_slot(dev), pci_get_function(dev));
	if (sc->my_cdev == NULL)
		return ENXIO;
	sc->my_cdev->si_drv1 = sc;

	for (i = 0; i < MAX_BARS; i++)
		sc->bar_res[i] = NULL;

	pci_enable_busmaster(dev);

	return 0;
}

static int
nic_uio_detach(device_t dev)
{
	int i;
	struct nic_uio_softc *sc;
	sc = device_get_softc(dev);

	for (i = 0; i < MAX_BARS; i++)
		if (sc->bar_res[i] != NULL) {

			if (PCI_BAR_IO(pci_read_config(dev, sc->bar_id[i], 4)))
				bus_release_resource(dev, SYS_RES_IOPORT, sc->bar_id[i],
						sc->bar_res[i]);
			else 
				bus_release_resource(dev, SYS_RES_MEMORY, sc->bar_id[i],
						sc->bar_res[i]);
		}

	if (sc->my_cdev != NULL)
		destroy_dev(sc->my_cdev);
	return 0;
}

static void
nic_uio_load(void)
{
        char *remaining;
        long bus = 0, device = 0, function = 0;
	int i, j, len;
	device_t dev;

	memset(bdf_str, 0, sizeof(bdf_str));
	TUNABLE_STR_FETCH("hw.nic_uio.bdfs", bdf_str, sizeof(bdf_str));
	remaining = bdf_str;
        len = strlen(remaining);

        for (i = 0; remaining && len >= 5 && i < len;i+=6) {
                if ( remaining[i + 1] == ':' && remaining[i + 3] == ':' ) {
                        bus = strtol(&remaining[i + 0],NULL,0);
                        device = strtol(&remaining[i + 2],NULL,0);
                        function = strtol(&remaining[i + 4],NULL,0);
			
			printf("nic_uio: trying to dettach %ld:%ld:%ld...\n", bus, device, function);
			dev = pci_find_bsf(bus, device, function);
	                if (dev != NULL) {
	                        for (j = 0; j < NUM_DEVICES; j++) {
	                                if (pci_get_vendor(dev) == devices[j].vend && pci_get_device(dev) == devices[j].dev) {
							printf("nic_uio: success in dettachment of : %ld:%ld:%ld!\n", bus, device, function);
                                                        device_detach(dev); }
				}
			}
                }
        }
}

static void
nic_uio_unload(void)
{
}

static int
nic_uio_shutdown(void)
{
	return (0);
}

static int
nic_uio_modevent(module_t mod, int type, void *arg)
{

	switch (type) {
	case MOD_LOAD:
		nic_uio_load();
		break;
	case MOD_UNLOAD:
		nic_uio_unload();
		break;
	case MOD_SHUTDOWN:
		nic_uio_shutdown();
		break;
	default:
		break;
	}

	return (0);
}