/*
 * This file is part of the UCB release of Plan 9. It is subject to the license
 * terms in the LICENSE file found in the top-level directory of this
 * distribution and at http://akaros.cs.berkeley.edu/files/Plan9License. No
 * part of the UCB release of Plan 9, including this file, may be copied,
 * modified, propagated, or distributed except according to the terms contained
 * in the LICENSE file.
 */

#include <vfs.h>
#include <kfs.h>
#include <slab.h>
#include <kmalloc.h>
#include <kref.h>
#include <string.h>
#include <stdio.h>
#include <assert.h>
#include <error.h>
#include <cpio.h>
#include <pmap.h>
#include <smp.h>
#include <ip.h>
#include <arch/io.h>

struct dev pcidevtab;

static char *devname(void)
{
	return pcidevtab.name;
}

enum {
	Qtopdir = 0,

	Qpcidir,
	Qpcictl,
	Qpciraw,

	PCI_CONFIG_SZ = 256,
};

#define TYPE(q)		((uint32_t)(q).path & 0x0F)
#define QID(c, t)	(((c)<<4)|(t))

static struct dirtab topdir[] = {
	{".", {Qtopdir, 0, QTDIR}, 0, 0555},
	{"pci", {Qpcidir, 0, QTDIR}, 0, 0555},
};

static int pcidirgen(struct chan *c, int t, int tbdf, struct dir *dp)
{
	struct qid q;

	q = (struct qid) {
	BUSBDF(tbdf) | t, 0, 0};
	switch (t) {
		case Qpcictl:
			snprintf(get_cur_genbuf(), GENBUF_SZ, "%d.%d.%dctl",
					 BUSBNO(tbdf), BUSDNO(tbdf), BUSFNO(tbdf));
			devdir(c, q, get_cur_genbuf(), 0, eve, 0444, dp);
			return 1;
		case Qpciraw:
			snprintf(get_cur_genbuf(), GENBUF_SZ, "%d.%d.%draw",
					 BUSBNO(tbdf), BUSDNO(tbdf), BUSFNO(tbdf));
			devdir(c, q, get_cur_genbuf(), 128, eve, 0664, dp);
			return 1;
	}
	return -1;
}

static int
pcigen(struct chan *c, char *, struct dirtab *, int unused_int, int s,
	   struct dir *dp)
{
	int tbdf;
	Pcidev *p;
	struct qid q;

	switch (TYPE(c->qid)) {
		case Qtopdir:
			if (s == DEVDOTDOT) {
				q = (struct qid) {
				QID(0, Qtopdir), 0, QTDIR};
				snprintf(get_cur_genbuf(), GENBUF_SZ, "#%C", pcidevtab.dc);
				devdir(c, q, get_cur_genbuf(), 0, eve, 0555, dp);
				return 1;
			}
			return devgen(c, NULL, topdir, ARRAY_SIZE(topdir), s, dp);
		case Qpcidir:
			if (s == DEVDOTDOT) {
				q = (struct qid) {
				QID(0, Qtopdir), 0, QTDIR};
				snprintf(get_cur_genbuf(), GENBUF_SZ, "#%C", pcidevtab.dc);
				devdir(c, q, get_cur_genbuf(), 0, eve, 0555, dp);
				return 1;
			}
			p = pcimatch(NULL, 0, 0);
			while (s >= 2 && p != NULL) {
				p = pcimatch(p, 0, 0);
				s -= 2;
			}
			if (p == NULL)
				return -1;
			return pcidirgen(c, s + Qpcictl, p->tbdf, dp);
		case Qpcictl:
		case Qpciraw:
			tbdf = MKBUS(BusPCI, 0, 0, 0) | BUSBDF((uint32_t) c->qid.path);
			p = pcimatchtbdf(tbdf);
			if (p == NULL)
				return -1;
			return pcidirgen(c, TYPE(c->qid), tbdf, dp);
		default:
			break;
	}
	return -1;
}

static struct chan *pciattach(char *spec)
{
	return devattach(devname(), spec);
}

struct walkqid *pciwalk(struct chan *c, struct chan *nc, char **name, int nname)
{
	return devwalk(c, nc, name, nname, (struct dirtab *)0, 0, pcigen);
}

static long pcistat(struct chan *c, uint8_t * dp, long n)
{
	return devstat(c, dp, n, (struct dirtab *)0, 0L, pcigen);
}

static struct chan *pciopen(struct chan *c, int omode)
{
	c = devopen(c, omode, (struct dirtab *)0, 0, pcigen);
	switch (TYPE(c->qid)) {
		default:
			break;
	}
	return c;
}

static void pciclose(struct chan *)
{
}

static long pciread(struct chan *c, void *va, long n, int64_t offset)
{
	char buf[PCI_CONFIG_SZ], *ebuf, *w, *a;
	int i, tbdf, r;
	uint32_t x;
	Pcidev *p;

	a = va;
	switch (TYPE(c->qid)) {
		case Qtopdir:
		case Qpcidir:
			return devdirread(c, a, n, (struct dirtab *)0, 0L, pcigen);
		case Qpcictl:
			tbdf = MKBUS(BusPCI, 0, 0, 0) | BUSBDF((uint32_t) c->qid.path);
			p = pcimatchtbdf(tbdf);
			if (p == NULL)
				error(EINVAL, ERROR_FIXME);
			ebuf = buf + sizeof buf - 1;	/* -1 for newline */
			w = seprintf(buf, ebuf, "%.2x.%.2x.%.2x %.4x/%.4x %3d",
						 p->ccrb, p->ccru, p->ccrp, p->vid, p->did, p->intl);
			for (i = 0; i < ARRAY_SIZE(p->mem); i++) {
				if (p->mem[i].size == 0)
					continue;
				w = seprintf(w, ebuf, " %d:%.8lux %d", i, p->mem[i].bar,
							 p->mem[i].size);
			}
			*w++ = '\n';
			*w = '\0';
			return readstr(offset, a, n, buf);
		case Qpciraw:
			tbdf = MKBUS(BusPCI, 0, 0, 0) | BUSBDF((uint32_t) c->qid.path);
			p = pcimatchtbdf(tbdf);
			if (p == NULL)
				error(EINVAL, ERROR_FIXME);
			if (n + offset > 256)
				n = 256 - offset;
			if (n < 0)
				return 0;
			r = offset;
			if (!(r & 3) && n == 4) {
				x = pcicfgr32(p, r);
				PBIT32(a, x);
				return 4;
			}
			if (!(r & 1) && n == 2) {
				x = pcicfgr16(p, r);
				PBIT16(a, x);
				return 2;
			}
			for (i = 0; i < n; i++) {
				x = pcicfgr8(p, r);
				PBIT8(a, x);
				a++;
				r++;
			}
			return i;
		default:
			error(EINVAL, ERROR_FIXME);
	}
	return n;
}

static long pciwrite(struct chan *c, void *va, long n, int64_t offset)
{
	uint8_t *a;
	int i, r, tbdf;
	uint32_t x;
	Pcidev *p;

	if (n > PCI_CONFIG_SZ)
		n = PCI_CONFIG_SZ;
	a = va;

	switch (TYPE(c->qid)) {
		case Qpciraw:
			tbdf = MKBUS(BusPCI, 0, 0, 0) | BUSBDF((uint32_t) c->qid.path);
			p = pcimatchtbdf(tbdf);
			if (p == NULL)
				error(EINVAL, ERROR_FIXME);
			if (offset > PCI_CONFIG_SZ)
				return 0;
			if (n + offset > PCI_CONFIG_SZ)
				n = PCI_CONFIG_SZ - offset;
			r = offset;
			if (!(r & 3) && n == 4) {
				x = GBIT32(a);
				pcicfgw32(p, r, x);
				return 4;
			}
			if (!(r & 1) && n == 2) {
				x = GBIT16(a);
				pcicfgw16(p, r, x);
				return 2;
			}
			for (i = 0; i < n; i++) {
				x = GBIT8(a);
				pcicfgw8(p, r, x);
				a++;
				r++;
			}
			return i;
		default:
			error(EINVAL, ERROR_FIXME);
	}
	return n;
}

struct dev pcidevtab = {
	.name = "pci",

	.reset = devreset,
	.init = devinit,
	.shutdown = devshutdown,
	.attach = pciattach,
	.walk = pciwalk,
	.stat = pcistat,
	.open = pciopen,
	.create = devcreate,
	.close = pciclose,
	.read = pciread,
	.bread = devbread,
	.write = pciwrite,
	.bwrite = devbwrite,
	.remove = devremove,
	.wstat = devwstat,
};