freebsd-skq/sys/dev/pci/vga_pci.c
jhb 08472642cd The recent PCI resource allocation fixes exposed a bug where the same
BAR could be allocated twice by different children of a vgapci0 device.
To fix this, change the vgapci0 device to track references on its associated
resources so that they are only allocated once from the parent PCI bus and
released when no children are using them.  Previously this leaked a small
amount of KVA on at least some architectures.
2009-03-04 21:04:52 +00:00

429 lines
11 KiB
C

/*-
* Copyright (c) 2005 John Baldwin <jhb@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. Neither the name of the author nor the names of any co-contributors
* may 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Simple driver for PCI VGA display devices. Drivers such as agp(4) and
* drm(4) should attach as children of this device.
*
* XXX: The vgapci name is a hack until we somehow merge the isa vga driver
* in or rename it.
*/
#include <sys/param.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/systm.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcivar.h>
struct vga_resource {
struct resource *vr_res;
int vr_refs;
};
struct vga_pci_softc {
device_t vga_msi_child; /* Child driver using MSI. */
struct vga_resource vga_res[PCIR_MAX_BAR_0 + 1];
};
static int
vga_pci_probe(device_t dev)
{
switch (pci_get_class(dev)) {
case PCIC_DISPLAY:
break;
case PCIC_OLD:
if (pci_get_subclass(dev) != PCIS_OLD_VGA)
return (ENXIO);
break;
default:
return (ENXIO);
}
device_set_desc(dev, "VGA-compatible display");
return (BUS_PROBE_GENERIC);
}
static int
vga_pci_attach(device_t dev)
{
bus_generic_probe(dev);
/* Always create a drm child for now to make it easier on drm. */
device_add_child(dev, "drm", -1);
bus_generic_attach(dev);
return (0);
}
static int
vga_pci_suspend(device_t dev)
{
return (bus_generic_suspend(dev));
}
static int
vga_pci_resume(device_t dev)
{
return (bus_generic_resume(dev));
}
/* Bus interface. */
static int
vga_pci_read_ivar(device_t dev, device_t child, int which, uintptr_t *result)
{
return (BUS_READ_IVAR(device_get_parent(dev), dev, which, result));
}
static int
vga_pci_write_ivar(device_t dev, device_t child, int which, uintptr_t value)
{
return (EINVAL);
}
static int
vga_pci_setup_intr(device_t dev, device_t child, struct resource *irq,
int flags, driver_filter_t *filter, driver_intr_t *intr, void *arg,
void **cookiep)
{
return (BUS_SETUP_INTR(device_get_parent(dev), dev, irq, flags,
filter, intr, arg, cookiep));
}
static int
vga_pci_teardown_intr(device_t dev, device_t child, struct resource *irq,
void *cookie)
{
return (BUS_TEARDOWN_INTR(device_get_parent(dev), dev, irq, cookie));
}
static struct resource *
vga_pci_alloc_resource(device_t dev, device_t child, int type, int *rid,
u_long start, u_long end, u_long count, u_int flags)
{
struct vga_pci_softc *sc;
int bar;
switch (type) {
case SYS_RES_MEMORY:
case SYS_RES_IOPORT:
/*
* For BARs, we cache the resource so that we only allocate it
* from the PCI bus once.
*/
bar = PCI_RID2BAR(*rid);
if (bar < 0 || bar > PCIR_MAX_BAR_0)
return (NULL);
sc = device_get_softc(dev);
if (sc->vga_res[bar].vr_res == NULL)
sc->vga_res[bar].vr_res = bus_alloc_resource(dev, type,
rid, start, end, count, flags);
if (sc->vga_res[bar].vr_res != NULL)
sc->vga_res[bar].vr_refs++;
return (sc->vga_res[bar].vr_res);
}
return (bus_alloc_resource(dev, type, rid, start, end, count, flags));
}
static int
vga_pci_release_resource(device_t dev, device_t child, int type, int rid,
struct resource *r)
{
struct vga_pci_softc *sc;
int bar, error;
switch (type) {
case SYS_RES_MEMORY:
case SYS_RES_IOPORT:
/*
* For BARs, we release the resource from the PCI bus
* when the last child reference goes away.
*/
bar = PCI_RID2BAR(rid);
if (bar < 0 || bar > PCIR_MAX_BAR_0)
return (EINVAL);
sc = device_get_softc(dev);
if (sc->vga_res[bar].vr_res == NULL)
return (EINVAL);
KASSERT(sc->vga_res[bar].vr_res == r,
("vga_pci resource mismatch"));
if (sc->vga_res[bar].vr_refs > 1) {
sc->vga_res[bar].vr_refs--;
return (0);
}
KASSERT(sc->vga_res[bar].vr_refs > 0,
("vga_pci resource reference count underflow"));
error = bus_release_resource(dev, type, rid, r);
if (error == 0) {
sc->vga_res[bar].vr_res = NULL;
sc->vga_res[bar].vr_refs = 0;
}
return (error);
}
return (bus_release_resource(dev, type, rid, r));
}
/* PCI interface. */
static uint32_t
vga_pci_read_config(device_t dev, device_t child, int reg, int width)
{
return (pci_read_config(dev, reg, width));
}
static void
vga_pci_write_config(device_t dev, device_t child, int reg,
uint32_t val, int width)
{
pci_write_config(dev, reg, val, width);
}
static int
vga_pci_enable_busmaster(device_t dev, device_t child)
{
device_printf(dev, "child %s requested pci_enable_busmaster\n",
device_get_nameunit(child));
return (pci_enable_busmaster(dev));
}
static int
vga_pci_disable_busmaster(device_t dev, device_t child)
{
device_printf(dev, "child %s requested pci_disable_busmaster\n",
device_get_nameunit(child));
return (pci_disable_busmaster(dev));
}
static int
vga_pci_enable_io(device_t dev, device_t child, int space)
{
device_printf(dev, "child %s requested pci_enable_io\n",
device_get_nameunit(child));
return (pci_enable_io(dev, space));
}
static int
vga_pci_disable_io(device_t dev, device_t child, int space)
{
device_printf(dev, "child %s requested pci_disable_io\n",
device_get_nameunit(child));
return (pci_disable_io(dev, space));
}
static int
vga_pci_get_vpd_ident(device_t dev, device_t child, const char **identptr)
{
return (pci_get_vpd_ident(dev, identptr));
}
static int
vga_pci_get_vpd_readonly(device_t dev, device_t child, const char *kw,
const char **vptr)
{
return (pci_get_vpd_readonly(dev, kw, vptr));
}
static int
vga_pci_set_powerstate(device_t dev, device_t child, int state)
{
device_printf(dev, "child %s requested pci_set_powerstate\n",
device_get_nameunit(child));
return (pci_set_powerstate(dev, state));
}
static int
vga_pci_get_powerstate(device_t dev, device_t child)
{
device_printf(dev, "child %s requested pci_get_powerstate\n",
device_get_nameunit(child));
return (pci_get_powerstate(dev));
}
static int
vga_pci_assign_interrupt(device_t dev, device_t child)
{
device_printf(dev, "child %s requested pci_assign_interrupt\n",
device_get_nameunit(child));
return (PCI_ASSIGN_INTERRUPT(device_get_parent(dev), dev));
}
static int
vga_pci_find_extcap(device_t dev, device_t child, int capability,
int *capreg)
{
return (pci_find_extcap(dev, capability, capreg));
}
static int
vga_pci_alloc_msi(device_t dev, device_t child, int *count)
{
struct vga_pci_softc *sc;
int error;
sc = device_get_softc(dev);
if (sc->vga_msi_child != NULL)
return (EBUSY);
error = pci_alloc_msi(dev, count);
if (error == 0)
sc->vga_msi_child = child;
return (error);
}
static int
vga_pci_alloc_msix(device_t dev, device_t child, int *count)
{
struct vga_pci_softc *sc;
int error;
sc = device_get_softc(dev);
if (sc->vga_msi_child != NULL)
return (EBUSY);
error = pci_alloc_msix(dev, count);
if (error == 0)
sc->vga_msi_child = child;
return (error);
}
static int
vga_pci_remap_msix(device_t dev, device_t child, int count,
const u_int *vectors)
{
struct vga_pci_softc *sc;
sc = device_get_softc(dev);
if (sc->vga_msi_child != child)
return (ENXIO);
return (pci_remap_msix(dev, count, vectors));
}
static int
vga_pci_release_msi(device_t dev, device_t child)
{
struct vga_pci_softc *sc;
int error;
sc = device_get_softc(dev);
if (sc->vga_msi_child != child)
return (ENXIO);
error = pci_release_msi(dev);
if (error == 0)
sc->vga_msi_child = NULL;
return (error);
}
static int
vga_pci_msi_count(device_t dev, device_t child)
{
return (pci_msi_count(dev));
}
static int
vga_pci_msix_count(device_t dev, device_t child)
{
return (pci_msix_count(dev));
}
static device_method_t vga_pci_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, vga_pci_probe),
DEVMETHOD(device_attach, vga_pci_attach),
DEVMETHOD(device_shutdown, bus_generic_shutdown),
DEVMETHOD(device_suspend, vga_pci_suspend),
DEVMETHOD(device_resume, vga_pci_resume),
/* Bus interface */
DEVMETHOD(bus_read_ivar, vga_pci_read_ivar),
DEVMETHOD(bus_write_ivar, vga_pci_write_ivar),
DEVMETHOD(bus_setup_intr, vga_pci_setup_intr),
DEVMETHOD(bus_teardown_intr, vga_pci_teardown_intr),
DEVMETHOD(bus_alloc_resource, vga_pci_alloc_resource),
DEVMETHOD(bus_release_resource, vga_pci_release_resource),
DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
/* PCI interface */
DEVMETHOD(pci_read_config, vga_pci_read_config),
DEVMETHOD(pci_write_config, vga_pci_write_config),
DEVMETHOD(pci_enable_busmaster, vga_pci_enable_busmaster),
DEVMETHOD(pci_disable_busmaster, vga_pci_disable_busmaster),
DEVMETHOD(pci_enable_io, vga_pci_enable_io),
DEVMETHOD(pci_disable_io, vga_pci_disable_io),
DEVMETHOD(pci_get_vpd_ident, vga_pci_get_vpd_ident),
DEVMETHOD(pci_get_vpd_readonly, vga_pci_get_vpd_readonly),
DEVMETHOD(pci_get_powerstate, vga_pci_get_powerstate),
DEVMETHOD(pci_set_powerstate, vga_pci_set_powerstate),
DEVMETHOD(pci_assign_interrupt, vga_pci_assign_interrupt),
DEVMETHOD(pci_find_extcap, vga_pci_find_extcap),
DEVMETHOD(pci_alloc_msi, vga_pci_alloc_msi),
DEVMETHOD(pci_alloc_msix, vga_pci_alloc_msix),
DEVMETHOD(pci_remap_msix, vga_pci_remap_msix),
DEVMETHOD(pci_release_msi, vga_pci_release_msi),
DEVMETHOD(pci_msi_count, vga_pci_msi_count),
DEVMETHOD(pci_msix_count, vga_pci_msix_count),
{ 0, 0 }
};
static driver_t vga_pci_driver = {
"vgapci",
vga_pci_methods,
sizeof(struct vga_pci_softc),
};
static devclass_t vga_devclass;
DRIVER_MODULE(vgapci, pci, vga_pci_driver, vga_devclass, 0, 0);