freebsd-dev/sys/sparc64/pci/ofw_pcib.c
John Baldwin 83c41143ca Reimplement how PCI-PCI bridges manage their I/O windows. Previously the
driver would verify that requests for child devices were confined to any
existing I/O windows, but the driver relied on the firmware to initialize
the windows and would never grow the windows for new requests.  Now the
driver actively manages the I/O windows.

This is implemented by allocating a bus resource for each I/O window from
the parent PCI bus and suballocating that resource to child devices.  The
suballocations are managed by creating an rman for each I/O window.  The
suballocated resources are mapped by passing the bus_activate_resource()
call up to the parent PCI bus.  Windows are grown when needed by using
bus_adjust_resource() to adjust the resource allocated from the parent PCI
bus.  If the adjust request succeeds, the window is adjusted and the
suballocation request for the child device is retried.

When growing a window, the rman_first_free_region() and
rman_last_free_region() routines are used to determine if the front or
end of the existing I/O window is free.  From using that, the smallest
ranges that need to be added to either the front or back of the window
are computed.  The driver will first try to grow the window in whichever
direction requires the smallest growth first followed by the other
direction if that fails.

Subtractive bridges will first attempt to satisfy requests for child
resources from I/O windows (including attempts to grow the windows).  If
that fails, the request is passed up to the parent PCI bus directly
however.

The PCI-PCI bridge driver will try to use firmware-assigned ranges for
child BARs first and only allocate a "fresh" range if that specific range
cannot be accommodated in the I/O window.  This allows systems where the
firmware assigns resources during boot but later wipes the I/O windows
(some ACPI BIOSen are known to do this) to "rediscover" the original I/O
window ranges.

The ACPI Host-PCI bridge driver has been adjusted to correctly honor
hw.acpi.host_mem_start and the I/O port equivalent when a PCI-PCI bridge
makes a wildcard request for an I/O window range.

The new PCI-PCI bridge driver is only enabled if the NEW_PCIB kernel option
is enabled.  This is a transition aide to allow platforms that do not
yet support bus_activate_resource() and bus_adjust_resource() in their
Host-PCI bridge drivers (and possibly other drivers as needed) to use the
old driver for now.  Once all platforms support the new driver, the
kernel option and old driver will be removed.

PR:		kern/143874 kern/149306
Tested by:	mav
2011-05-03 17:37:24 +00:00

140 lines
4.2 KiB
C

/*-
* Copyright (c) 1994,1995 Stefan Esser, Wolfgang StanglMeier
* Copyright (c) 2000 Michael Smith <msmith@freebsd.org>
* Copyright (c) 2000 BSDi
* Copyright (c) 2001 - 2003 Thomas Moestl <tmm@FreeBSD.org>
* Copyright (c) 2009 by Marius Strobl <marius@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, 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. 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 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 AUTHOR 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.
*
* from: FreeBSD: src/sys/dev/pci/pci_pci.c,v 1.3 2000/12/13
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_ofw_pci.h"
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/libkern.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <dev/ofw/ofw_bus.h>
#include <dev/ofw/openfirm.h>
#include <machine/bus.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcib_private.h>
#include "pcib_if.h"
#include <sparc64/pci/ofw_pci.h>
#include <sparc64/pci/ofw_pcib_subr.h>
static device_probe_t ofw_pcib_probe;
static device_attach_t ofw_pcib_attach;
static device_method_t ofw_pcib_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, ofw_pcib_probe),
DEVMETHOD(device_attach, ofw_pcib_attach),
/* Bus interface */
/* pcib interface */
DEVMETHOD(pcib_route_interrupt, ofw_pcib_gen_route_interrupt),
/* ofw_bus interface */
DEVMETHOD(ofw_bus_get_node, ofw_pcib_gen_get_node),
KOBJMETHOD_END
};
static devclass_t pcib_devclass;
DEFINE_CLASS_1(pcib, ofw_pcib_driver, ofw_pcib_methods,
sizeof(struct ofw_pcib_gen_softc), pcib_driver);
EARLY_DRIVER_MODULE(ofw_pcib, pci, ofw_pcib_driver, pcib_devclass, 0, 0,
BUS_PASS_BUS);
MODULE_DEPEND(ofw_pcib, pci, 1, 1, 1);
static int
ofw_pcib_probe(device_t dev)
{
char desc[sizeof("OFW PCIe-PCIe bridge")];
const char *dtype, *pbdtype;
#define ISDTYPE(dtype, type) \
(((dtype) != NULL) && strcmp((dtype), (type)) == 0)
if ((pci_get_class(dev) == PCIC_BRIDGE) &&
(pci_get_subclass(dev) == PCIS_BRIDGE_PCI) &&
ofw_bus_get_node(dev) != 0) {
dtype = ofw_bus_get_type(dev);
pbdtype = ofw_bus_get_type(device_get_parent(
device_get_parent(dev)));
snprintf(desc, sizeof(desc), "OFW PCI%s-PCI%s bridge",
ISDTYPE(pbdtype, OFW_TYPE_PCIE) ? "e" : "",
ISDTYPE(dtype, OFW_TYPE_PCIE) ? "e" : "");
device_set_desc_copy(dev, desc);
return (0);
}
#undef ISDTYPE
return (ENXIO);
}
static int
ofw_pcib_attach(device_t dev)
{
struct ofw_pcib_gen_softc *sc;
sc = device_get_softc(dev);
/* Quirk handling */
switch (pci_get_devid(dev)) {
/*
* The ALi M5249 found in Fire-based machines by definition must me
* subtractive as they have a ISA bridge on their secondary side but
* don't indicate this in the class code although the ISA I/O range
* isn't included in their bridge decode.
*/
case 0x524910b9:
sc->ops_pcib_sc.flags |= PCIB_SUBTRACTIVE;
break;
}
ofw_pcib_gen_setup(dev);
pcib_attach_common(dev);
device_add_child(dev, "pci", -1);
return (bus_generic_attach(dev));
}