/*-
 * Copyright (c) 1997, Stefan Esser <se@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 unmodified, 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.
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD: src/sys/amd64/pci/pci_bus.c,v 1.116 2006/01/06 19:22:18 jhb Exp $");

#include "opt_cpu.h"

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/sysctl.h>

#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcib_private.h>
#include <isa/isavar.h>
#include <machine/legacyvar.h>
#include <machine/pci_cfgreg.h>
#include <machine/resource.h>

#include "pcib_if.h"

int
legacy_pcib_maxslots(device_t dev)
{
	return 31;
}

/* read configuration space register */

u_int32_t
legacy_pcib_read_config(device_t dev, int bus, int slot, int func,
			int reg, int bytes)
{
	return(pci_cfgregread(bus, slot, func, reg, bytes));
}

/* write configuration space register */

void
legacy_pcib_write_config(device_t dev, int bus, int slot, int func,
			 int reg, u_int32_t data, int bytes)
{
	pci_cfgregwrite(bus, slot, func, reg, data, bytes);
}

/* route interrupt */

static int
legacy_pcib_route_interrupt(device_t pcib, device_t dev, int pin)
{

	/* No routing possible */
	return (PCI_INVALID_IRQ);
}

static const char *
legacy_pcib_is_host_bridge(int bus, int slot, int func,
			  uint32_t id, uint8_t class, uint8_t subclass,
			  uint8_t *busnum)
{
	const char *s = NULL;

	*busnum = 0;
	if (class == PCIC_BRIDGE && subclass == PCIS_BRIDGE_HOST)
		s = "Host to PCI bridge";
	return s;
}

/*
 * Scan the first pci bus for host-pci bridges and add pcib instances
 * to the nexus for each bridge.
 */
static void
legacy_pcib_identify(driver_t *driver, device_t parent)
{
	int bus, slot, func;
	u_int8_t  hdrtype;
	int found = 0;
	int pcifunchigh;
	int found824xx = 0;
	int found_orion = 0;
	device_t child;
	devclass_t pci_devclass;

	if (pci_cfgregopen() == 0)
		return;
	/*
	 * Check to see if we haven't already had a PCI bus added
	 * via some other means.  If we have, bail since otherwise
	 * we're going to end up duplicating it.
	 */
	if ((pci_devclass = devclass_find("pci")) &&
		devclass_get_device(pci_devclass, 0))
		return;


	bus = 0;
 retry:
	for (slot = 0; slot <= PCI_SLOTMAX; slot++) {
		func = 0;
		hdrtype = legacy_pcib_read_config(0, bus, slot, func,
						 PCIR_HDRTYPE, 1);
		/*
		 * When enumerating bus devices, the standard says that
		 * one should check the header type and ignore the slots whose
		 * header types that the software doesn't know about.  We use
		 * this to filter out devices.
		 */
		if ((hdrtype & PCIM_HDRTYPE) > PCI_MAXHDRTYPE)
			continue;
		if ((hdrtype & PCIM_MFDEV) &&
		    (!found_orion || hdrtype != 0xff))
			pcifunchigh = PCI_FUNCMAX;
		else
			pcifunchigh = 0;
		for (func = 0; func <= pcifunchigh; func++) {
			/*
			 * Read the IDs and class from the device.
			 */
			u_int32_t id;
			u_int8_t class, subclass, busnum;
			const char *s;
			device_t *devs;
			int ndevs, i;

			id = legacy_pcib_read_config(0, bus, slot, func,
						    PCIR_DEVVENDOR, 4);
			if (id == -1)
				continue;
			class = legacy_pcib_read_config(0, bus, slot, func,
						       PCIR_CLASS, 1);
			subclass = legacy_pcib_read_config(0, bus, slot, func,
							  PCIR_SUBCLASS, 1);

			s = legacy_pcib_is_host_bridge(bus, slot, func,
						      id, class, subclass,
						      &busnum);
			if (s == NULL)
				continue;

			/*
			 * Check to see if the physical bus has already
			 * been seen.  Eg: hybrid 32 and 64 bit host
			 * bridges to the same logical bus.
			 */
			if (device_get_children(parent, &devs, &ndevs) == 0) {
				for (i = 0; s != NULL && i < ndevs; i++) {
					if (strcmp(device_get_name(devs[i]),
					    "pcib") != 0)
						continue;
					if (legacy_get_pcibus(devs[i]) == busnum)
						s = NULL;
				}
				free(devs, M_TEMP);
			}

			if (s == NULL)
				continue;
			/*
			 * Add at priority 100 to make sure we
			 * go after any motherboard resources
			 */
			child = BUS_ADD_CHILD(parent, 100,
					      "pcib", busnum);
			device_set_desc(child, s);
			legacy_set_pcibus(child, busnum);

			found = 1;
			if (id == 0x12258086)
				found824xx = 1;
			if (id == 0x84c48086)
				found_orion = 1;
		}
	}
	if (found824xx && bus == 0) {
		bus++;
		goto retry;
	}

	/*
	 * Make sure we add at least one bridge since some old
	 * hardware doesn't actually have a host-pci bridge device.
	 * Note that pci_cfgregopen() thinks we have PCI devices..
	 */
	if (!found) {
		if (bootverbose)
			printf(
	"legacy_pcib_identify: no bridge found, adding pcib0 anyway\n");
		child = BUS_ADD_CHILD(parent, 100, "pcib", 0);
		legacy_set_pcibus(child, 0);
	}
}

static int
legacy_pcib_probe(device_t dev)
{

	if (pci_cfgregopen() == 0)
		return ENXIO;
	return -100;
}

static int
legacy_pcib_attach(device_t dev)
{
	int bus;

	bus = pcib_get_bus(dev);
	device_add_child(dev, "pci", bus);
	return bus_generic_attach(dev);
}

int
legacy_pcib_read_ivar(device_t dev, device_t child, int which,
    uintptr_t *result)
{

	switch (which) {
	case  PCIB_IVAR_BUS:
		*result = legacy_get_pcibus(dev);
		return 0;
	}
	return ENOENT;
}

int
legacy_pcib_write_ivar(device_t dev, device_t child, int which,
    uintptr_t value)
{

	switch (which) {
	case  PCIB_IVAR_BUS:
		legacy_set_pcibus(dev, value);
		return 0;
	}
	return ENOENT;
}

SYSCTL_DECL(_hw_pci);

static unsigned long legacy_host_mem_start = 0x80000000;
TUNABLE_ULONG("hw.pci.host_mem_start", &legacy_host_mem_start);
SYSCTL_ULONG(_hw_pci, OID_AUTO, host_mem_start, CTLFLAG_RDTUN,
    &legacy_host_mem_start, 0x80000000,
    "Limit the host bridge memory to being above this address.  Must be\n\
set at boot via a tunable.");

struct resource *
legacy_pcib_alloc_resource(device_t dev, device_t child, int type, int *rid,
    u_long start, u_long end, u_long count, u_int flags)
{
    /*
     * If no memory preference is given, use upper 32MB slot most
     * bioses use for their memory window.  Typically other bridges
     * before us get in the way to assert their preferences on memory.
     * Hardcoding like this sucks, so a more MD/MI way needs to be
     * found to do it.  This is typically only used on older laptops
     * that don't have pci busses behind pci bridge, so assuming > 32MB
     * is liekly OK.
     *
     * However, this can cause problems for other chipsets, so we make
     * this tunable by hw.pci.host_mem_start.
     */
    if (type == SYS_RES_MEMORY && start == 0UL && end == ~0UL)
	start = legacy_host_mem_start;
    if (type == SYS_RES_IOPORT && start == 0UL && end == ~0UL)
	start = 0x1000;
    return (bus_generic_alloc_resource(dev, child, type, rid, start, end,
	count, flags));
}

static device_method_t legacy_pcib_methods[] = {
	/* Device interface */
	DEVMETHOD(device_identify,	legacy_pcib_identify),
	DEVMETHOD(device_probe,		legacy_pcib_probe),
	DEVMETHOD(device_attach,	legacy_pcib_attach),
	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
	DEVMETHOD(device_suspend,	bus_generic_suspend),
	DEVMETHOD(device_resume,	bus_generic_resume),

	/* Bus interface */
	DEVMETHOD(bus_print_child,	bus_generic_print_child),
	DEVMETHOD(bus_read_ivar,	legacy_pcib_read_ivar),
	DEVMETHOD(bus_write_ivar,	legacy_pcib_write_ivar),
	DEVMETHOD(bus_alloc_resource,	legacy_pcib_alloc_resource),
	DEVMETHOD(bus_release_resource,	bus_generic_release_resource),
	DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
	DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
	DEVMETHOD(bus_setup_intr,	bus_generic_setup_intr),
	DEVMETHOD(bus_teardown_intr,	bus_generic_teardown_intr),

	/* pcib interface */
	DEVMETHOD(pcib_maxslots,	legacy_pcib_maxslots),
	DEVMETHOD(pcib_read_config,	legacy_pcib_read_config),
	DEVMETHOD(pcib_write_config,	legacy_pcib_write_config),
	DEVMETHOD(pcib_route_interrupt,	legacy_pcib_route_interrupt),

	{ 0, 0 }
};

static devclass_t pcib_devclass;

DEFINE_CLASS_0(pcib, legacy_pcib_driver, legacy_pcib_methods, 1);
DRIVER_MODULE(pcib, legacy, legacy_pcib_driver, pcib_devclass, 0, 0);


/*
 * Install placeholder to claim the resources owned by the
 * PCI bus interface.  This could be used to extract the
 * config space registers in the extreme case where the PnP
 * ID is available and the PCI BIOS isn't, but for now we just
 * eat the PnP ID and do nothing else.
 *
 * XXX we should silence this probe, as it will generally confuse
 * people.
 */
static struct isa_pnp_id pcibus_pnp_ids[] = {
	{ 0x030ad041 /* PNP0A03 */, "PCI Bus" },
	{ 0 }
};

static int
pcibus_pnp_probe(device_t dev)
{
	int result;

	if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, pcibus_pnp_ids)) <= 0)
		device_quiet(dev);
	return(result);
}

static int
pcibus_pnp_attach(device_t dev)
{
	return(0);
}

static device_method_t pcibus_pnp_methods[] = {
	/* Device interface */
	DEVMETHOD(device_probe,		pcibus_pnp_probe),
	DEVMETHOD(device_attach,	pcibus_pnp_attach),
	DEVMETHOD(device_detach,	bus_generic_detach),
	DEVMETHOD(device_shutdown,	bus_generic_shutdown),
	DEVMETHOD(device_suspend,	bus_generic_suspend),
	DEVMETHOD(device_resume,	bus_generic_resume),
	{ 0, 0 }
};

static devclass_t pcibus_pnp_devclass;

DEFINE_CLASS_0(pcibus_pnp, pcibus_pnp_driver, pcibus_pnp_methods, 1);
DRIVER_MODULE(pcibus_pnp, isa, pcibus_pnp_driver, pcibus_pnp_devclass, 0, 0);
