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path: root/sys/arch/sgi/xbow/xbow.c
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/*	$OpenBSD: xbow.c,v 1.6 2009/05/02 21:30:13 miod Exp $	*/

/*
 * Copyright (c) 2008, 2009 Miodrag Vallat.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */
/*
 * Copyright (c) 2004 Opsycon AB  (www.opsycon.se)
 *
 * 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.
 *
 */

/*
 *  XBOW is the mux between two nodes and XIO.
 *
 *  A Crossbow (XBOW) connects two nodeboards via their respecive
 *  HUB to up to six different I/O controllers in XIO slots. In a
 *  multiprocessor system all processors have access to the XIO
 *  slots but may need to pass traffic via the routers.
 *
 *  To each XIO port on the XBOW a XIO interface is attached. Such
 *  interfaces can be for example PCI bridges wich then add another
 *  level to the hierarchy.
 */

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

#include <mips64/archtype.h>

#include <machine/atomic.h>
#include <machine/autoconf.h>
#include <machine/intr.h>
#include <machine/mnode.h>

#include <sgi/xbow/hub.h>
#include <sgi/xbow/xbow.h>
#include <sgi/xbow/xbowdevs.h>
#include <sgi/xbow/xbowdevs_data.h>

int	xbowmatch(struct device *, void *, void *);
void	xbowattach(struct device *, struct device *, void *);
int	xbowprint_pass1(void *, const char *);
int	xbowprint_pass2(void *, const char *);
int	xbowsubmatch_pass1(struct device *, void *, void *);
int	xbowsubmatch_pass2(struct device *, void *, void *);
int	xbow_attach_widget(struct device *, int16_t, int,
	    int (*)(struct device *, void *, void *), cfprint_t);
void	xbow_enumerate(struct device *, int16_t, int,
	    int (*)(struct device *, void *, void *), cfprint_t);

uint32_t xbow_read_4(bus_space_tag_t, bus_space_handle_t, bus_size_t);
uint64_t xbow_read_8(bus_space_tag_t, bus_space_handle_t, bus_size_t);
void	xbow_write_4(bus_space_tag_t, bus_space_handle_t, bus_size_t, uint32_t);
void	xbow_write_8(bus_space_tag_t, bus_space_handle_t, bus_size_t, uint64_t);
void	xbow_read_raw_2(bus_space_tag_t, bus_space_handle_t, bus_addr_t,
	    uint8_t *, bus_size_t);
void	xbow_write_raw_2(bus_space_tag_t, bus_space_handle_t, bus_addr_t,
	    const uint8_t *, bus_size_t);
void	xbow_read_raw_4(bus_space_tag_t, bus_space_handle_t, bus_addr_t,
	    uint8_t *, bus_size_t);
void	xbow_write_raw_4(bus_space_tag_t, bus_space_handle_t, bus_addr_t,
	    const uint8_t *, bus_size_t);
void	xbow_read_raw_8(bus_space_tag_t, bus_space_handle_t, bus_addr_t,
	    uint8_t *, bus_size_t);
void	xbow_write_raw_8(bus_space_tag_t, bus_space_handle_t, bus_addr_t,
	    const uint8_t *, bus_size_t);

int	xbow_space_map_long(bus_space_tag_t, bus_addr_t, bus_size_t, int,
	    bus_space_handle_t *);
void	xbow_space_unmap(bus_space_tag_t, bus_space_handle_t, bus_size_t);
int	xbow_space_region_short(bus_space_tag_t, bus_space_handle_t, bus_size_t,
	    bus_size_t, bus_space_handle_t *);
int	xbow_space_region_long(bus_space_tag_t, bus_space_handle_t, bus_size_t,
	    bus_size_t, bus_space_handle_t *);
void	*xbow_space_vaddr(bus_space_tag_t, bus_space_handle_t);

const struct xbow_product *xbow_identify(uint32_t, uint32_t);

const struct cfattach xbow_ca = {
	sizeof(struct device), xbowmatch, xbowattach
};

struct cfdriver xbow_cd = {
	NULL, "xbow", DV_DULL
};

static const bus_space_t xbowbus_short_tag = {
	NULL,
	(bus_addr_t)0,		/* will be modified in widgets bus_space_t */
	NULL,
	0,
	xbow_read_1,
	xbow_write_1,
	xbow_read_2,
	xbow_write_2,
	xbow_read_4,
	xbow_write_4,
	xbow_read_8,
	xbow_write_8,
	xbow_read_raw_2,
	xbow_write_raw_2,
	xbow_read_raw_4,
	xbow_write_raw_4,
	xbow_read_raw_8,
	xbow_write_raw_8,
	xbow_space_map_short,
	xbow_space_unmap,
	xbow_space_region_short

};

static const bus_space_t xbowbus_long_tag = {
	NULL,
	(bus_addr_t)0,		/* will be modified in widgets bus_space_t */
	NULL,
	0,
	xbow_read_1,
	xbow_write_1,
	xbow_read_2,
	xbow_write_2,
	xbow_read_4,
	xbow_write_4,
	xbow_read_8,
	xbow_write_8,
	xbow_read_raw_2,
	xbow_write_raw_2,
	xbow_read_raw_4,
	xbow_write_raw_4,
	xbow_read_raw_8,
	xbow_write_raw_8,
	xbow_space_map_long,
	xbow_space_unmap,
	xbow_space_region_long

};

/*
 * Function pointers to hide widget window mapping differences accross
 * systems.
 */
paddr_t	(*xbow_widget_short)(int16_t, u_int);
paddr_t	(*xbow_widget_long)(int16_t, u_int);
unsigned int xbow_long_shift = 29;

int	(*xbow_widget_id)(int16_t, u_int, uint32_t *);

/*
 * Attachment glue.
 */

int
xbowmatch(struct device *parent, void *match, void *aux)
{
	switch (sys_config.system_type) {
	case SGI_O200:
	case SGI_O300:
	case SGI_OCTANE:
		return (1);
	default:
		return (0);
	}
}

const struct xbow_product *
xbow_identify(uint32_t vendor, uint32_t product)
{
	const struct xbow_product *p;

	for (p = xbow_products; p->productname != NULL; p++)
		if (p->vendor == vendor && p->product == product)
			return p;

	return NULL;
}

int
xbowprint_pass1(void *aux, const char *pnp)
{
	struct xbow_attach_args *xaa = aux;
	const struct xbow_product *p;

	p = xbow_identify(xaa->xaa_vendor, xaa->xaa_product);

	if (pnp == NULL) {
		printf(" widget %d", xaa->xaa_widget);
		if (p != NULL)
			printf(": %s", p->productname);
	}

	return (QUIET);
}

int
xbowprint_pass2(void *aux, const char *pnp)
{
	struct xbow_attach_args *xaa = aux;
	const struct xbow_product *p;

	p = xbow_identify(xaa->xaa_vendor, xaa->xaa_product);

	if (pnp != NULL) {
		if (p != NULL)
			printf("\"%s\"", p->productname);
		else
			printf("vendor %x product %x",
			    xaa->xaa_vendor, xaa->xaa_product);
		printf(" revision %d at %s",
		    xaa->xaa_revision, pnp);
	}
	printf(" widget %d", xaa->xaa_widget);
	if (pnp == NULL) {
		if (p != NULL)
			printf(": %s", p->productname);
	}

	return (UNCONF);
}

int
xbowsubmatch_pass1(struct device *parent, void *vcf, void *aux)
{
	int rc;

	if (xbow_intr_widget != 0)
		return 0;

	rc = xbowsubmatch_pass2(parent, vcf, aux);
	if (rc < 20)
		rc = 0;

	return rc;
}

int
xbowsubmatch_pass2(struct device *parent, void *vcf, void *aux)
{
	struct xbow_attach_args *xaa = aux;
	struct cfdata *cf = vcf;

	if (cf->cf_loc[0] != -1 && cf->cf_loc[0] != xaa->xaa_vendor)
		return 0;
	if (cf->cf_loc[1] != -1 && cf->cf_loc[1] != xaa->xaa_product)
		return 0;

	return (*cf->cf_attach->ca_match)(parent, vcf, aux);
}

void
xbowattach(struct device *parent, struct device *self, void *aux)
{
	int16_t nasid = 0;	/* XXX for now... */
	uint32_t wid, vendor, product;
	const struct xbow_product *p;

	/*
	 * This assumes widget 0 is the XBow itself (or an XXBow).
	 * If it isn't - feel free to haunt my bedroom at night.
	 */
	if (xbow_widget_id(nasid, 0, &wid) != 0)
		panic("no xbow");
	vendor = (wid & WIDGET_ID_VENDOR_MASK) >> WIDGET_ID_VENDOR_SHIFT;
	product = (wid & WIDGET_ID_PRODUCT_MASK) >> WIDGET_ID_PRODUCT_SHIFT;
	p = xbow_identify(vendor, product);
	printf(": %s revision %d\n",
	    p != NULL ? p->productname : "unknown xbow",
	    (wid & WIDGET_ID_REV_MASK) >> WIDGET_ID_REV_SHIFT);

	/*
	 * Default value for the interrupt register. If this system
	 * has a Heart widget, the Heart code will take care of changing it.
	 */
	xbow_intr_widget_register = (1UL << 47) /* XIO I/O space */ |
	    ((paddr_t)IP27_RHUB_ADDR(nasid, HUB_IR_CHANGE) -
	     IP27_NODE_IO_BASE(0)) /* HUB register offset */;

	/*
	 * If widget 0 reports itself as a bridge, this is not a
	 * complete XBow, but only a limited topology. This is
	 * found on at least the Origin 200.
	 */
	if (vendor == XBOW_VENDOR_SGI4 && product == XBOW_PRODUCT_SGI4_BRIDGE) {
		/*
		 * Interrupt widget is hardwired to #a (this is another
		 * facet of this bridge).
		 */
		xbow_intr_widget = 0x0a;

		xbow_attach_widget(self, nasid, WIDGET_MIN,
		    xbowsubmatch_pass2, xbowprint_pass2);
	} else {
		/*
		 * XXX This widget number is actually the Hub part of the
		 * XXX crossbow, and is where memory and interrupt logic
		 * XXX resources are connected to.
		 * XXX The exact widget number ought to be computed from
		 * XXX the KL configuration graph; I'm hardcoding it for
		 * XXX now because I am lazy and we only care about the
		 * XXX first node at the moment. -- miod
		 */
		if (sys_config.system_type != SGI_OCTANE)
			xbow_intr_widget = 0x0a;

		/*
		 * Enumerate the other widgets.
		 * We'll do two passes - one to give the first Heart or a Hub a
		 * chance to setup interrupt routing, and one to attach all
		 * other widgets.
		 */
		if (xbow_intr_widget == 0)
			xbow_enumerate(self, nasid, 0,
			    xbowsubmatch_pass1, xbowprint_pass1);
		xbow_enumerate(self, nasid, xbow_intr_widget,
		    xbowsubmatch_pass2, xbowprint_pass2);
	}
}

void
xbow_enumerate(struct device *self, int16_t nasid, int skip,
    int (*sm)(struct device *, void *, void *), cfprint_t print)
{
	int widget;

	for (widget = WIDGET_MIN; widget <= WIDGET_MAX; widget++) {
		if (widget == skip)
			continue;

		(void)xbow_attach_widget(self, nasid, widget, sm, print);
	}
}

int
xbow_attach_widget(struct device *self, int16_t nasid, int widget,
    int (*sm)(struct device *, void *, void *), cfprint_t print)
{
	struct xbow_attach_args xaa;
	uint32_t wid;
	struct mips_bus_space *bs, *bl;
	int rc;

	if ((rc = xbow_widget_id(nasid, widget, &wid)) != 0)
		return rc;

	/*
	 * Build a pair of bus_space_t suitable for this widget.
	 */
	bs = malloc(sizeof (*bs), M_DEVBUF, M_NOWAIT);
	if (bs == NULL)
		return ENOMEM;
	bl = malloc(sizeof (*bl), M_DEVBUF, M_NOWAIT);
	if (bl == NULL) {
		free(bs, M_DEVBUF);
		return ENOMEM;
	}

	xbow_build_bus_space(bs, nasid, widget, 0);
	xbow_build_bus_space(bl, nasid, widget, 1);

	xaa.xaa_widget = widget;
	xaa.xaa_vendor = (wid & WIDGET_ID_VENDOR_MASK) >>
	    WIDGET_ID_VENDOR_SHIFT;
	xaa.xaa_product = (wid & WIDGET_ID_PRODUCT_MASK) >>
	    WIDGET_ID_PRODUCT_SHIFT;
	xaa.xaa_revision = (wid & WIDGET_ID_REV_MASK) >> WIDGET_ID_REV_SHIFT;
	xaa.xaa_short_tag = bs;
	xaa.xaa_long_tag = bl;

	if (config_found_sm(self, &xaa, print, sm) == NULL) {
		/* nothing attached, no need to keep the bus_space */
		free(bs, M_DEVBUF);
		free(bl, M_DEVBUF);

		return ENOENT;
	}

	return 0;
}


/*
 * Bus access primitives.
 */

void
xbow_build_bus_space(struct mips_bus_space *bs, int nasid, int widget, int lwin)
{
	if (lwin) {
		bcopy(&xbowbus_long_tag, bs, sizeof (*bs));
		bs->bus_base = (*xbow_widget_long)(nasid, widget);
	} else {
		bcopy(&xbowbus_short_tag, bs, sizeof (*bs));
		bs->bus_base = (*xbow_widget_short)(nasid, widget);
	}
}

uint8_t
xbow_read_1(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o)
{
	return *(volatile uint8_t *)(h + o);
}

uint16_t
xbow_read_2(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o)
{
	return *(volatile uint16_t *)(h + o);
}

uint32_t
xbow_read_4(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o)
{
	return *(volatile uint32_t *)(h + o);
}

uint64_t
xbow_read_8(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o)
{
	return *(volatile uint64_t *)(h + o);
}

void
xbow_write_1(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o, uint8_t v)
{
	*(volatile uint8_t *)(h + o) = v;
}

void
xbow_write_2(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o, uint16_t v)
{
	*(volatile uint16_t *)(h + o) = v;
}

void
xbow_write_4(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o, uint32_t v)
{
	*(volatile uint32_t *)(h + o) = v;
}

void
xbow_write_8(bus_space_tag_t t, bus_space_handle_t h, bus_size_t o, uint64_t v)
{
	*(volatile uint64_t *)(h + o) = v;
}

void
xbow_read_raw_2(bus_space_tag_t t, bus_space_handle_t h, bus_addr_t o,
    uint8_t *buf, bus_size_t len)
{
	len >>= 1;
	while (len-- != 0) {
		*(uint16_t *)buf = *(volatile uint16_t *)(h + o);
		buf += 2;
	}
}

void
xbow_write_raw_2(bus_space_tag_t t, bus_space_handle_t h, bus_addr_t o,
    const uint8_t *buf, bus_size_t len)
{
	len >>= 1;
	while (len-- != 0) {
		*(volatile uint16_t *)(h + o) = *(uint16_t *)buf;
		buf += 2;
	}
}

void
xbow_read_raw_4(bus_space_tag_t t, bus_space_handle_t h, bus_addr_t o,
    uint8_t *buf, bus_size_t len)
{
	len >>= 2;
	while (len-- != 0) {
		*(uint32_t *)buf = *(volatile uint32_t *)(h + o);
		buf += 4;
	}
}

void
xbow_write_raw_4(bus_space_tag_t t, bus_space_handle_t h, bus_addr_t o,
    const uint8_t *buf, bus_size_t len)
{
	len >>= 2;
	while (len-- != 0) {
		*(volatile uint32_t *)(h + o) = *(uint32_t *)buf;
		buf += 4;
	}
}

void
xbow_read_raw_8(bus_space_tag_t t, bus_space_handle_t h, bus_addr_t o,
    uint8_t *buf, bus_size_t len)
{
	len >>= 3;
	while (len-- != 0) {
		*(uint64_t *)buf = *(volatile uint64_t *)(h + o);
		buf += 8;
	}
}

void
xbow_write_raw_8(bus_space_tag_t t, bus_space_handle_t h, bus_addr_t o,
    const uint8_t *buf, bus_size_t len)
{
	len >>= 3;
	while (len-- != 0) {
		*(volatile uint64_t *)(h + o) = *(uint64_t *)buf;
		buf += 8;
	}
}

int
xbow_space_map_short(bus_space_tag_t t, bus_addr_t offs, bus_size_t size,
    int cacheable, bus_space_handle_t *bshp)
{
	bus_addr_t bpa;

	bpa = t->bus_base + offs;

	/* check that this does not overflow the window */
	if (((bpa + size - 1) >> 24) != (t->bus_base >> 24))
		return (EINVAL);

	*bshp = bpa;
	return 0;
}

int
xbow_space_map_long(bus_space_tag_t t, bus_addr_t offs, bus_size_t size,
    int cacheable, bus_space_handle_t *bshp)
{
	bus_addr_t bpa;

	bpa = t->bus_base + offs;

	/* check that this does not overflow the window */
	if (((bpa + size - 1) >> xbow_long_shift) !=
	    (t->bus_base >> xbow_long_shift))
		return (EINVAL);

	*bshp = bpa;
	return 0;
}

void
xbow_space_unmap(bus_space_tag_t t, bus_space_handle_t bsh, bus_size_t size)
{
}

int
xbow_space_region_short(bus_space_tag_t t, bus_space_handle_t bsh,
    bus_size_t offset, bus_size_t size, bus_space_handle_t *nbshp)
{
	/* check that this does not overflow the window */
	if (((bsh + offset) >> 24) != (bsh >> 24))
		return (EINVAL);

	*nbshp = bsh + offset;
	return 0;
}

int
xbow_space_region_long(bus_space_tag_t t, bus_space_handle_t bsh,
    bus_size_t offset, bus_size_t size, bus_space_handle_t *nbshp)
{
	/* check that this does not overflow the window */
	if (((bsh + offset) >> xbow_long_shift) != (bsh >> xbow_long_shift))
		return (EINVAL);

	*nbshp = bsh + offset;
	return 0;
}

void *
xbow_space_vaddr(bus_space_tag_t t, bus_space_handle_t h)
{
	return (void *)h;
}

/*
 * Interrupt handling code.
 *
 * Interrupt handling should be done at the Heart/Hub driver level, we only
 * act as a proxy here.
 */

int	xbow_intr_widget = 0;
paddr_t	xbow_intr_widget_register;
int	(*xbow_intr_widget_intr_register)(int, int, int *) = NULL;
int	(*xbow_intr_widget_intr_establish)(int (*)(void *), void *, int, int,
	    const char *) = NULL;
void	(*xbow_intr_widget_intr_disestablish)(int) = NULL;

int
xbow_intr_register(int widget, int level, int *intrbit)
{
	if (xbow_intr_widget_intr_register == NULL)
		return EINVAL;

	return (*xbow_intr_widget_intr_register)(widget, level, intrbit);
}

int
xbow_intr_establish(int (*func)(void *), void *arg, int intrbit, int level,
    const char *name)
{
	if (xbow_intr_widget_intr_establish == NULL)
		return EINVAL;

	return (*xbow_intr_widget_intr_establish)(func, arg, intrbit, level,
	    name);
}

void
xbow_intr_disestablish(int intrbit)
{
	if (xbow_intr_widget_intr_disestablish == NULL)
		return;

	(*xbow_intr_widget_intr_disestablish)(intrbit);
}