/*	$OpenBSD: pci.c,v 1.45 2006/03/22 00:36:03 jsg Exp $	*/
/*	$NetBSD: pci.c,v 1.31 1997/06/06 23:48:04 thorpej Exp $	*/

/*
 * Copyright (c) 1995, 1996 Christopher G. Demetriou.  All rights reserved.
 * Copyright (c) 1994 Charles Hannum.  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.
 * 3. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by Charles Hannum.
 * 4. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * 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.
 */

/*
 * PCI bus autoconfiguration.
 */

#include <sys/param.h>
#include <sys/systm.h>
#include <sys/device.h>
#include <sys/malloc.h>

#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcidevs.h>

int pcimatch(struct device *, void *, void *);
void pciattach(struct device *, struct device *, void *);
void pcipower(int, void *);

#define NMAPREG			((PCI_MAPREG_END - PCI_MAPREG_START) / \
				    sizeof(pcireg_t))
struct pci_dev {
	LIST_ENTRY(pci_dev) pd_next;
	struct device *pd_dev;
	pcitag_t pd_tag;        /* pci register tag */
	pcireg_t pd_csr;
	pcireg_t pd_bhlc;
	pcireg_t pd_int;
	pcireg_t pd_map[NMAPREG];
};

#ifdef APERTURE
extern int allowaperture;
#endif

struct cfattach pci_ca = {
	sizeof(struct pci_softc), pcimatch, pciattach
};

struct cfdriver pci_cd = {
	NULL, "pci", DV_DULL
};

int	pciprint(void *, const char *);
int	pcisubmatch(struct device *, void *, void *);

#ifdef PCI_MACHDEP_ENUMERATE_BUS
#define pci_enumerate_bus PCI_MACHDEP_ENUMERATE_BUS
#else
int pci_enumerate_bus(struct pci_softc *,
    int (*)(struct pci_attach_args *), struct pci_attach_args *);
#endif

/*
 * Important note about PCI-ISA bridges:
 *
 * Callbacks are used to configure these devices so that ISA/EISA bridges
 * can attach their child busses after PCI configuration is done.
 *
 * This works because:
 *	(1) there can be at most one ISA/EISA bridge per PCI bus, and
 *	(2) any ISA/EISA bridges must be attached to primary PCI
 *	    busses (i.e. bus zero).
 *
 * That boils down to: there can only be one of these outstanding
 * at a time, it is cleared when configuring PCI bus 0 before any
 * subdevices have been found, and it is run after all subdevices
 * of PCI bus 0 have been found.
 *
 * This is needed because there are some (legacy) PCI devices which
 * can show up as ISA/EISA devices as well (the prime example of which
 * are VGA controllers).  If you attach ISA from a PCI-ISA/EISA bridge,
 * and the bridge is seen before the video board is, the board can show
 * up as an ISA device, and that can (bogusly) complicate the PCI device's
 * attach code, or make the PCI device not be properly attached at all.
 *
 * We use the generic config_defer() facility to achieve this.
 */

int
pcimatch(struct device *parent, void *match, void *aux)
{
	struct cfdata *cf = match;
	struct pcibus_attach_args *pba = aux;

	if (strcmp(pba->pba_busname, cf->cf_driver->cd_name))
		return (0);

	/* Check the locators */
	if (cf->pcibuscf_bus != PCIBUS_UNK_BUS &&
	    cf->pcibuscf_bus != pba->pba_bus)
		return (0);

	/* sanity */
	if (pba->pba_bus < 0 || pba->pba_bus > 255)
		return (0);

	/*
	 * XXX check other (hardware?) indicators
	 */

	return (1);
}

void
pciattach(struct device *parent, struct device *self, void *aux)
{
	struct pcibus_attach_args *pba = aux;
	struct pci_softc *sc = (struct pci_softc *)self;

	pci_attach_hook(parent, self, pba);

	printf("\n");

	LIST_INIT(&sc->sc_devs);
	sc->sc_powerhook = powerhook_establish(pcipower, sc);

	sc->sc_iot = pba->pba_iot;
	sc->sc_memt = pba->pba_memt;
	sc->sc_dmat = pba->pba_dmat;
	sc->sc_pc = pba->pba_pc;
	sc->sc_bus = pba->pba_bus;
	sc->sc_bridgetag = pba->pba_bridgetag;
	sc->sc_maxndevs = pci_bus_maxdevs(pba->pba_pc, pba->pba_bus);
	sc->sc_intrswiz = pba->pba_intrswiz;
	sc->sc_intrtag = pba->pba_intrtag;
	pci_enumerate_bus(sc, NULL, NULL);
}

/* save and restore the pci config space */
void
pcipower(int why, void *arg)
{
	struct pci_softc *sc = (struct pci_softc *)arg;
	struct pci_dev *pd;
	pcireg_t reg;
	int i;

	LIST_FOREACH(pd, &sc->sc_devs, pd_next) {
		if (why != PWR_RESUME) {
			for (i = 0; i < NMAPREG; i++)
			       pd->pd_map[i] = pci_conf_read(sc->sc_pc,
				   pd->pd_tag, PCI_MAPREG_START + (i * 4));
			pd->pd_csr = pci_conf_read(sc->sc_pc, pd->pd_tag,
			   PCI_COMMAND_STATUS_REG);
			pd->pd_bhlc = pci_conf_read(sc->sc_pc, pd->pd_tag,
			   PCI_BHLC_REG);
			pd->pd_int = pci_conf_read(sc->sc_pc, pd->pd_tag,
			   PCI_INTERRUPT_REG);
		} else {
			for (i = 0; i < NMAPREG; i++)
				pci_conf_write(sc->sc_pc, pd->pd_tag,
				    PCI_MAPREG_START + (i * 4),
					pd->pd_map[i]);
			reg = pci_conf_read(sc->sc_pc, pd->pd_tag,
			    PCI_COMMAND_STATUS_REG);
			pci_conf_write(sc->sc_pc, pd->pd_tag,
			    PCI_COMMAND_STATUS_REG,
			    (reg & 0xffff0000) | (pd->pd_csr & 0x0000ffff));
			pci_conf_write(sc->sc_pc, pd->pd_tag, PCI_BHLC_REG,
			    pd->pd_bhlc);
			pci_conf_write(sc->sc_pc, pd->pd_tag, PCI_INTERRUPT_REG,
			    pd->pd_int);
		}
	}
}

int
pciprint(void *aux, const char *pnp)
{
	struct pci_attach_args *pa = aux;
	char devinfo[256];

	if (pnp) {
		pci_devinfo(pa->pa_id, pa->pa_class, 1, devinfo,
		    sizeof devinfo);
		printf("%s at %s", devinfo, pnp);
	}
	printf(" dev %d function %d", pa->pa_device, pa->pa_function);
	if (!pnp) {
		pci_devinfo(pa->pa_id, pa->pa_class, 0, devinfo,
		    sizeof devinfo);
		printf(" %s", devinfo);
	}

	return (UNCONF);
}

int
pcisubmatch(struct device *parent, void *match,  void *aux)
{
	struct cfdata *cf = match;
	struct pci_attach_args *pa = aux;
	int success;

	if (cf->pcicf_dev != PCI_UNK_DEV &&
	    cf->pcicf_dev != pa->pa_device)
		return (0);
	if (cf->pcicf_function != PCI_UNK_FUNCTION &&
	    cf->pcicf_function != pa->pa_function)
		return (0);

	success = (*cf->cf_attach->ca_match)(parent, match, aux);

	/*
	 * My Dell BIOS does not enable certain non-critical PCI devices
	 * for IO and memory cycles (e.g. network card). This is
	 * the generic approach to fixing this problem. Basically, if
	 * we support the card, then we enable its IO cycles.
	 */
	if (success) {
		pcireg_t csr = pci_conf_read(pa->pa_pc, pa->pa_tag,
		    PCI_COMMAND_STATUS_REG);

		pci_conf_write(pa->pa_pc, pa->pa_tag, PCI_COMMAND_STATUS_REG,
		    csr | PCI_COMMAND_MASTER_ENABLE |
		    PCI_COMMAND_IO_ENABLE | PCI_COMMAND_MEM_ENABLE);
	}

	return (success);
}

int
pci_probe_device(struct pci_softc *sc, pcitag_t tag,
    int (*match)(struct pci_attach_args *), struct pci_attach_args *pap)
{
	pci_chipset_tag_t pc = sc->sc_pc;
	struct pci_attach_args pa;
	struct pci_dev *pd;
	struct device *dev;
	pcireg_t id, csr, class, intr, bhlcr;
	int ret, pin, bus, device, function;

	pci_decompose_tag(pc, tag, &bus, &device, &function);

	bhlcr = pci_conf_read(pc, tag, PCI_BHLC_REG);
	if (PCI_HDRTYPE_TYPE(bhlcr) > 2)
		return (0);

	id = pci_conf_read(pc, tag, PCI_ID_REG);
	csr = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
	class = pci_conf_read(pc, tag, PCI_CLASS_REG);

	/* Invalid vendor ID value? */
	if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
		return (0);
	/* XXX Not invalid, but we've done this ~forever. */
	if (PCI_VENDOR(id) == 0)
		return (0);

	pa.pa_iot = sc->sc_iot;
	pa.pa_memt = sc->sc_memt;
	pa.pa_dmat = sc->sc_dmat;
	pa.pa_pc = pc;
	pa.pa_bus = bus;
	pa.pa_device = device;
	pa.pa_function = function;
	pa.pa_tag = tag;
	pa.pa_id = id;
	pa.pa_class = class;

	/* This is a simplification of the NetBSD code.
	   We don't support turning off I/O or memory
	   on broken hardware. <csapuntz@stanford.edu> */
	pa.pa_flags = PCI_FLAGS_IO_ENABLED | PCI_FLAGS_MEM_ENABLED;

#ifdef __i386__
	/*
	 * on i386 we really need to know the device tag
	 * and not the pci bridge tag, in intr_map
	 * to be able to program the device and the
	 * pci interrupt router.
	 */
	pa.pa_intrtag = tag;
	pa.pa_intrswiz = 0;
#else
	if (sc->sc_bridgetag == NULL) {
		pa.pa_intrswiz = 0;
		pa.pa_intrtag = tag;
	} else {
		pa.pa_intrswiz = sc->sc_intrswiz + device;
		pa.pa_intrtag = sc->sc_intrtag;
	}
#endif

	intr = pci_conf_read(pc, tag, PCI_INTERRUPT_REG);

	pin = PCI_INTERRUPT_PIN(intr);
	pa.pa_rawintrpin = pin;
	if (pin == PCI_INTERRUPT_PIN_NONE) {
		/* no interrupt */
		pa.pa_intrpin = 0;
	} else {
		/*
		 * swizzle it based on the number of busses we're
		 * behind and our device number.
		 */
		pa.pa_intrpin = 	/* XXX */
		    ((pin + pa.pa_intrswiz - 1) % 4) + 1;
	}
	pa.pa_intrline = PCI_INTERRUPT_LINE(intr);

	if (match != NULL) {
		ret = (*match)(&pa);
		if (ret != 0 && pap != NULL)
			*pap = pa;
	} else {
		if ((dev = config_found_sm(&sc->sc_dev, &pa, pciprint,
		    pcisubmatch))) {
				pcireg_t reg;

				/* skip header type != 0 */
				reg = pci_conf_read(pc, tag, PCI_BHLC_REG);
				if (PCI_HDRTYPE_TYPE(reg) != 0)
					return(0);
				if (pci_get_capability(pc, tag,
				    PCI_CAP_PWRMGMT, NULL, NULL) == 0)
					return(0);
				if (!(pd = malloc(sizeof *pd, M_DEVBUF,
				    M_NOWAIT)))
					return(0);
				pd->pd_tag = tag;
				pd->pd_dev = dev;
				LIST_INSERT_HEAD(&sc->sc_devs, pd, pd_next);
			}
	}

	return (ret);
}

int
pci_get_capability(pci_chipset_tag_t pc, pcitag_t tag, int capid,
    int *offset, pcireg_t *value)
{
	pcireg_t reg;
	unsigned int ofs;

	reg = pci_conf_read(pc, tag, PCI_COMMAND_STATUS_REG);
	if (!(reg & PCI_STATUS_CAPLIST_SUPPORT))
		return (0);

	/* Determine the Capability List Pointer register to start with. */
	reg = pci_conf_read(pc, tag, PCI_BHLC_REG);
	switch (PCI_HDRTYPE_TYPE(reg)) {
	case 0:	/* standard device header */
		ofs = PCI_CAPLISTPTR_REG;
		break;
	case 2:	/* PCI-CardBus Bridge header */
		ofs = PCI_CARDBUS_CAPLISTPTR_REG;
		break;
	default:
		return (0);
	}

	ofs = PCI_CAPLIST_PTR(pci_conf_read(pc, tag, ofs));
	while (ofs != 0) {
#ifdef DIAGNOSTIC
		if ((ofs & 3) || (ofs < 0x40))
			panic("pci_get_capability");
#endif
		reg = pci_conf_read(pc, tag, ofs);
		if (PCI_CAPLIST_CAP(reg) == capid) {
			if (offset)
				*offset = ofs;
			if (value)
				*value = reg;
			return (1);
		}
		ofs = PCI_CAPLIST_NEXT(reg);
	}

	return (0);
}

int
pci_find_device(struct pci_attach_args *pa,
		int (*match)(struct pci_attach_args *))
{
	extern struct cfdriver pci_cd;
	struct device *pcidev;
	int i;

	for (i = 0; i < pci_cd.cd_ndevs; i++) {
		pcidev = pci_cd.cd_devs[i];
		if (pcidev != NULL &&
		    pci_enumerate_bus((struct pci_softc *)pcidev,
		    		      match, pa) != 0)
			return (1);
	}
	return (0);
}

#ifndef PCI_MACHDEP_ENUMERATE_BUS
/*
 * Generic PCI bus enumeration routine.  Used unless machine-dependent
 * code needs to provide something else.
 */
int
pci_enumerate_bus(struct pci_softc *sc,
    int (*match)(struct pci_attach_args *), struct pci_attach_args *pap)
{
	pci_chipset_tag_t pc = sc->sc_pc;
	int device, function, nfunctions, ret;
	const struct pci_quirkdata *qd;
	pcireg_t id, bhlcr;
	pcitag_t tag;

	for (device = 0; device < sc->sc_maxndevs; device++) {
		tag = pci_make_tag(pc, sc->sc_bus, device, 0);

		bhlcr = pci_conf_read(pc, tag, PCI_BHLC_REG);
		if (PCI_HDRTYPE_TYPE(bhlcr) > 2)
			continue;

		id = pci_conf_read(pc, tag, PCI_ID_REG);

		/* Invalid vendor ID value? */
		if (PCI_VENDOR(id) == PCI_VENDOR_INVALID)
			continue;
		/* XXX Not invalid, but we've done this ~forever. */
		if (PCI_VENDOR(id) == 0)
			continue;

		qd = pci_lookup_quirkdata(PCI_VENDOR(id), PCI_PRODUCT(id));

		if (qd != NULL &&
		      (qd->quirks & PCI_QUIRK_MULTIFUNCTION) != 0)
			nfunctions = 8;
		else if (qd != NULL &&
		      (qd->quirks & PCI_QUIRK_MONOFUNCTION) != 0)
			nfunctions = 1;
		else
			nfunctions = PCI_HDRTYPE_MULTIFN(bhlcr) ? 8 : 1;

		for (function = 0; function < nfunctions; function++) {
			tag = pci_make_tag(pc, sc->sc_bus, device, function);
			ret = pci_probe_device(sc, tag, match, pap);
			if (match != NULL && ret != 0)
				return (ret);
		}
 	}

	return (0);
}
#endif /* PCI_MACHDEP_ENUMERATE_BUS */

int
pci_matchbyid(struct pci_attach_args *pa, const struct pci_matchid *ids,
    int nent)
{
	const struct pci_matchid *pm;
	int i;

	for (i = 0, pm = ids; i < nent; i++, pm++)
		if (PCI_VENDOR(pa->pa_id) == pm->pm_vid &&
		    PCI_PRODUCT(pa->pa_id) == pm->pm_pid)
			return (1);
	return (0);
}

#ifdef USER_PCICONF
/*
 * This is the user interface to PCI configuration space.
 */
  
#include <sys/pciio.h>
#include <sys/fcntl.h>

#ifdef DEBUG
#define PCIDEBUG(x) printf x
#else
#define PCIDEBUG(x)
#endif


int pciopen(dev_t dev, int oflags, int devtype, struct proc *p);
int pciclose(dev_t dev, int flag, int devtype, struct proc *p);
int pciioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p);

int
pciopen(dev_t dev, int oflags, int devtype, struct proc *p) 
{
	PCIDEBUG(("pciopen ndevs: %d\n" , pci_cd.cd_ndevs));

#ifndef APERTURE
	if ((oflags & FWRITE) && securelevel > 0) {
		return EPERM;
	}
#else
	if ((oflags & FWRITE) && securelevel > 0 && allowaperture == 0) {
		return EPERM;
	}
#endif
	return (0);
}

int
pciclose(dev_t dev, int flag, int devtype, struct proc *p)
{
	PCIDEBUG(("pciclose\n"));
	return (0);
}

int
pciioctl(dev_t dev, u_long cmd, caddr_t data, int flag, struct proc *p)
{
	struct pci_io *io;
	int error;
	pcitag_t tag;
	struct pci_softc *pci;
	pci_chipset_tag_t pc;

	io = (struct pci_io *)data;

	PCIDEBUG(("pciioctl cmd %s", cmd == PCIOCREAD ? "pciocread" 
		  : cmd == PCIOCWRITE ? "pciocwrite" : "unknown"));
	PCIDEBUG(("  bus %d dev %d func %d reg %x\n", io->pi_sel.pc_bus,
		  io->pi_sel.pc_dev, io->pi_sel.pc_func, io->pi_reg));

	if (io->pi_sel.pc_bus >= pci_cd.cd_ndevs) {
		error = ENXIO;
		goto done;
	}
	pci = pci_cd.cd_devs[io->pi_sel.pc_bus];
	if (pci != NULL) {
		pc = pci->sc_pc;
	} else {
		error = ENXIO;
		goto done;
	}
	/* Check bounds */
	if (pci->sc_bus >= 256 || 
	    io->pi_sel.pc_dev >= pci_bus_maxdevs(pc, pci->sc_bus) ||
	    io->pi_sel.pc_func >= 8) {
		error = EINVAL;
		goto done;
	}

	tag = pci_make_tag(pc, pci->sc_bus, io->pi_sel.pc_dev,
			   io->pi_sel.pc_func);

	switch(cmd) {
	case PCIOCGETCONF:
		error = ENODEV;
		break;

	case PCIOCREAD:
		switch(io->pi_width) {
		case 4:
			/* Make sure the register is properly aligned */
			if (io->pi_reg & 0x3) 
				return EINVAL;
			io->pi_data = pci_conf_read(pc, tag, io->pi_reg);
			error = 0;
			break;
		default:
			error = ENODEV;
			break;
		}
		break;

	case PCIOCWRITE:
		if (!(flag & FWRITE))
			return EPERM;

		switch(io->pi_width) {
		case 4:
			/* Make sure the register is properly aligned */
			if (io->pi_reg & 0x3)
				return EINVAL;
			pci_conf_write(pc, tag, io->pi_reg, io->pi_data);
			error = 0;
			break;
		default:
			error = ENODEV;
			break;
		}
		break;

	default:
		error = ENOTTY;
		break;
	}
 done:
	return (error);
}

#endif