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freebsd-skq/sys/x86/pci/pci_bus.c

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/*-
* Copyright (c) 1997, Stefan Esser <se@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 unmodified, 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.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include "opt_cpu.h"
#include <sys/param.h>
#include <sys/systm.h>
#include <sys/bus.h>
#include <sys/kernel.h>
#include <sys/malloc.h>
#include <sys/module.h>
#include <sys/rman.h>
#include <sys/sysctl.h>
#include <dev/pci/pcivar.h>
#include <dev/pci/pcireg.h>
#include <dev/pci/pcib_private.h>
#include <isa/isavar.h>
#ifdef CPU_ELAN
#include <machine/md_var.h>
#endif
#include <x86/legacyvar.h>
#include <machine/pci_cfgreg.h>
#include <machine/resource.h>
#include "pcib_if.h"
int
legacy_pcib_maxslots(device_t dev)
{
return 31;
}
/* read configuration space register */
uint32_t
legacy_pcib_read_config(device_t dev, u_int bus, u_int slot, u_int func,
u_int reg, int bytes)
{
return(pci_cfgregread(bus, slot, func, reg, bytes));
}
/* write configuration space register */
void
legacy_pcib_write_config(device_t dev, u_int bus, u_int slot, u_int func,
u_int reg, uint32_t data, int bytes)
{
pci_cfgregwrite(bus, slot, func, reg, data, bytes);
}
/* route interrupt */
static int
legacy_pcib_route_interrupt(device_t pcib, device_t dev, int pin)
{
#ifdef __HAVE_PIR
return (pci_pir_route_interrupt(pci_get_bus(dev), pci_get_slot(dev),
pci_get_function(dev), pin));
#else
/* No routing possible */
return (PCI_INVALID_IRQ);
#endif
}
/* Pass MSI requests up to the nexus. */
int
legacy_pcib_alloc_msi(device_t pcib, device_t dev, int count, int maxcount,
int *irqs)
{
device_t bus;
bus = device_get_parent(pcib);
return (PCIB_ALLOC_MSI(device_get_parent(bus), dev, count, maxcount,
irqs));
}
int
legacy_pcib_alloc_msix(device_t pcib, device_t dev, int *irq)
{
device_t bus;
bus = device_get_parent(pcib);
return (PCIB_ALLOC_MSIX(device_get_parent(bus), dev, irq));
}
int
legacy_pcib_map_msi(device_t pcib, device_t dev, int irq, uint64_t *addr,
uint32_t *data)
{
device_t bus, hostb;
int error, func, slot;
bus = device_get_parent(pcib);
error = PCIB_MAP_MSI(device_get_parent(bus), dev, irq, addr, data);
if (error)
return (error);
slot = legacy_get_pcislot(pcib);
func = legacy_get_pcifunc(pcib);
if (slot == -1 || func == -1)
return (0);
hostb = pci_find_bsf(0, slot, func);
KASSERT(hostb != NULL, ("%s: missing hostb for 0:%d:%d", __func__,
slot, func));
pci_ht_map_msi(hostb, *addr);
return (0);
}
static const char *
legacy_pcib_is_host_bridge(int bus, int slot, int func,
uint32_t id, uint8_t class, uint8_t subclass,
uint8_t *busnum)
{
#ifdef __i386__
const char *s = NULL;
static uint8_t pxb[4]; /* hack for 450nx */
*busnum = 0;
switch (id) {
case 0x12258086:
s = "Intel 824?? host to PCI bridge";
/* XXX This is a guess */
/* *busnum = legacy_pcib_read_config(0, bus, slot, func, 0x41, 1); */
*busnum = bus;
break;
case 0x71208086:
s = "Intel 82810 (i810 GMCH) Host To Hub bridge";
break;
case 0x71228086:
s = "Intel 82810-DC100 (i810-DC100 GMCH) Host To Hub bridge";
break;
case 0x71248086:
s = "Intel 82810E (i810E GMCH) Host To Hub bridge";
break;
case 0x11308086:
s = "Intel 82815 (i815 GMCH) Host To Hub bridge";
break;
case 0x71808086:
s = "Intel 82443LX (440 LX) host to PCI bridge";
break;
case 0x71908086:
s = "Intel 82443BX (440 BX) host to PCI bridge";
break;
case 0x71928086:
s = "Intel 82443BX host to PCI bridge (AGP disabled)";
break;
case 0x71948086:
s = "Intel 82443MX host to PCI bridge";
break;
case 0x71a08086:
s = "Intel 82443GX host to PCI bridge";
break;
case 0x71a18086:
s = "Intel 82443GX host to AGP bridge";
break;
case 0x71a28086:
s = "Intel 82443GX host to PCI bridge (AGP disabled)";
break;
case 0x84c48086:
s = "Intel 82454KX/GX (Orion) host to PCI bridge";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0x4a, 1);
break;
case 0x84ca8086:
/*
* For the 450nx chipset, there is a whole bundle of
* things pretending to be host bridges. The MIOC will
* be seen first and isn't really a pci bridge (the
* actual busses are attached to the PXB's). We need to
* read the registers of the MIOC to figure out the
* bus numbers for the PXB channels.
*
* Since the MIOC doesn't have a pci bus attached, we
* pretend it wasn't there.
*/
pxb[0] = legacy_pcib_read_config(0, bus, slot, func,
0xd0, 1); /* BUSNO[0] */
pxb[1] = legacy_pcib_read_config(0, bus, slot, func,
0xd1, 1) + 1; /* SUBA[0]+1 */
pxb[2] = legacy_pcib_read_config(0, bus, slot, func,
0xd3, 1); /* BUSNO[1] */
pxb[3] = legacy_pcib_read_config(0, bus, slot, func,
0xd4, 1) + 1; /* SUBA[1]+1 */
return NULL;
case 0x84cb8086:
switch (slot) {
case 0x12:
s = "Intel 82454NX PXB#0, Bus#A";
*busnum = pxb[0];
break;
case 0x13:
s = "Intel 82454NX PXB#0, Bus#B";
*busnum = pxb[1];
break;
case 0x14:
s = "Intel 82454NX PXB#1, Bus#A";
*busnum = pxb[2];
break;
case 0x15:
s = "Intel 82454NX PXB#1, Bus#B";
*busnum = pxb[3];
break;
}
break;
case 0x1A308086:
s = "Intel 82845 Host to PCI bridge";
break;
/* AMD -- vendor 0x1022 */
case 0x30001022:
s = "AMD Elan SC520 host to PCI bridge";
#ifdef CPU_ELAN
init_AMD_Elan_sc520();
#else
printf(
"*** WARNING: missing CPU_ELAN -- timekeeping may be wrong\n");
#endif
break;
case 0x70061022:
s = "AMD-751 host to PCI bridge";
break;
case 0x700e1022:
s = "AMD-761 host to PCI bridge";
break;
/* SiS -- vendor 0x1039 */
case 0x04961039:
s = "SiS 85c496";
break;
case 0x04061039:
s = "SiS 85c501";
break;
case 0x06011039:
s = "SiS 85c601";
break;
case 0x55911039:
s = "SiS 5591 host to PCI bridge";
break;
case 0x00011039:
s = "SiS 5591 host to AGP bridge";
break;
/* VLSI -- vendor 0x1004 */
case 0x00051004:
s = "VLSI 82C592 Host to PCI bridge";
break;
/* XXX Here is MVP3, I got the datasheet but NO M/B to test it */
/* totally. Please let me know if anything wrong. -F */
/* XXX need info on the MVP3 -- any takers? */
case 0x05981106:
s = "VIA 82C598MVP (Apollo MVP3) host bridge";
break;
/* AcerLabs -- vendor 0x10b9 */
/* Funny : The datasheet told me vendor id is "10b8",sub-vendor */
/* id is '10b9" but the register always shows "10b9". -Foxfair */
case 0x154110b9:
s = "AcerLabs M1541 (Aladdin-V) PCI host bridge";
break;
/* OPTi -- vendor 0x1045 */
case 0xc7011045:
s = "OPTi 82C700 host to PCI bridge";
break;
case 0xc8221045:
s = "OPTi 82C822 host to PCI Bridge";
break;
/* ServerWorks -- vendor 0x1166 */
case 0x00051166:
s = "ServerWorks NB6536 2.0HE host to PCI bridge";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0x44, 1);
break;
case 0x00061166:
/* FALLTHROUGH */
case 0x00081166:
/* FALLTHROUGH */
case 0x02011166:
/* FALLTHROUGH */
case 0x010f1014: /* IBM re-badged ServerWorks chipset */
s = "ServerWorks host to PCI bridge";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0x44, 1);
break;
case 0x00091166:
s = "ServerWorks NB6635 3.0LE host to PCI bridge";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0x44, 1);
break;
case 0x00101166:
s = "ServerWorks CIOB30 host to PCI bridge";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0x44, 1);
break;
case 0x00111166:
/* FALLTHROUGH */
case 0x03021014: /* IBM re-badged ServerWorks chipset */
s = "ServerWorks CMIC-HE host to PCI-X bridge";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0x44, 1);
break;
/* XXX unknown chipset, but working */
case 0x00171166:
/* FALLTHROUGH */
case 0x01011166:
case 0x01101166:
case 0x02251166:
s = "ServerWorks host to PCI bridge(unknown chipset)";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0x44, 1);
break;
/* Compaq/HP -- vendor 0x0e11 */
case 0x60100e11:
s = "Compaq/HP Model 6010 HotPlug PCI Bridge";
*busnum = legacy_pcib_read_config(0, bus, slot, func, 0xc8, 1);
break;
/* Integrated Micro Solutions -- vendor 0x10e0 */
case 0x884910e0:
s = "Integrated Micro Solutions VL Bridge";
break;
default:
if (class == PCIC_BRIDGE && subclass == PCIS_BRIDGE_HOST)
s = "Host to PCI bridge";
break;
}
return s;
#else
const char *s = NULL;
*busnum = 0;
if (class == PCIC_BRIDGE && subclass == PCIS_BRIDGE_HOST)
s = "Host to PCI bridge";
return s;
#endif
}
/*
* Scan the first pci bus for host-pci bridges and add pcib instances
* to the nexus for each bridge.
*/
static void
legacy_pcib_identify(driver_t *driver, device_t parent)
{
int bus, slot, func;
uint8_t hdrtype;
int found = 0;
int pcifunchigh;
int found824xx = 0;
int found_orion = 0;
device_t child;
devclass_t pci_devclass;
if (pci_cfgregopen() == 0)
return;
/*
* Check to see if we haven't already had a PCI bus added
* via some other means. If we have, bail since otherwise
* we're going to end up duplicating it.
*/
if ((pci_devclass = devclass_find("pci")) &&
devclass_get_device(pci_devclass, 0))
return;
bus = 0;
retry:
for (slot = 0; slot <= PCI_SLOTMAX; slot++) {
func = 0;
hdrtype = legacy_pcib_read_config(0, bus, slot, func,
PCIR_HDRTYPE, 1);
/*
* When enumerating bus devices, the standard says that
* one should check the header type and ignore the slots whose
* header types that the software doesn't know about. We use
* this to filter out devices.
*/
if ((hdrtype & PCIM_HDRTYPE) > PCI_MAXHDRTYPE)
continue;
if ((hdrtype & PCIM_MFDEV) &&
(!found_orion || hdrtype != 0xff))
pcifunchigh = PCI_FUNCMAX;
else
pcifunchigh = 0;
for (func = 0; func <= pcifunchigh; func++) {
/*
* Read the IDs and class from the device.
*/
uint32_t id;
uint8_t class, subclass, busnum;
const char *s;
device_t *devs;
int ndevs, i;
id = legacy_pcib_read_config(0, bus, slot, func,
PCIR_DEVVENDOR, 4);
if (id == -1)
continue;
class = legacy_pcib_read_config(0, bus, slot, func,
PCIR_CLASS, 1);
subclass = legacy_pcib_read_config(0, bus, slot, func,
PCIR_SUBCLASS, 1);
s = legacy_pcib_is_host_bridge(bus, slot, func,
id, class, subclass,
&busnum);
if (s == NULL)
continue;
/*
* Check to see if the physical bus has already
* been seen. Eg: hybrid 32 and 64 bit host
* bridges to the same logical bus.
*/
if (device_get_children(parent, &devs, &ndevs) == 0) {
for (i = 0; s != NULL && i < ndevs; i++) {
if (strcmp(device_get_name(devs[i]),
"pcib") != 0)
continue;
if (legacy_get_pcibus(devs[i]) == busnum)
s = NULL;
}
free(devs, M_TEMP);
}
if (s == NULL)
continue;
/*
* Add at priority 100 to make sure we
* go after any motherboard resources
*/
child = BUS_ADD_CHILD(parent, 100,
"pcib", busnum);
device_set_desc(child, s);
legacy_set_pcibus(child, busnum);
legacy_set_pcislot(child, slot);
legacy_set_pcifunc(child, func);
found = 1;
if (id == 0x12258086)
found824xx = 1;
if (id == 0x84c48086)
found_orion = 1;
}
}
if (found824xx && bus == 0) {
bus++;
goto retry;
}
/*
* Make sure we add at least one bridge since some old
* hardware doesn't actually have a host-pci bridge device.
* Note that pci_cfgregopen() thinks we have PCI devices..
*/
if (!found) {
if (bootverbose)
printf(
"legacy_pcib_identify: no bridge found, adding pcib0 anyway\n");
child = BUS_ADD_CHILD(parent, 100, "pcib", 0);
legacy_set_pcibus(child, 0);
}
}
static int
legacy_pcib_probe(device_t dev)
{
if (pci_cfgregopen() == 0)
return ENXIO;
return -100;
}
static int
legacy_pcib_attach(device_t dev)
{
#ifdef __HAVE_PIR
device_t pir;
#endif
int bus;
bus = pcib_get_bus(dev);
#ifdef __HAVE_PIR
/*
* Look for a PCI BIOS interrupt routing table as that will be
* our method of routing interrupts if we have one.
*/
if (pci_pir_probe(bus, 0)) {
pir = BUS_ADD_CHILD(device_get_parent(dev), 0, "pir", 0);
if (pir != NULL)
device_probe_and_attach(pir);
}
#endif
device_add_child(dev, "pci", bus);
return bus_generic_attach(dev);
}
int
legacy_pcib_read_ivar(device_t dev, device_t child, int which,
uintptr_t *result)
{
switch (which) {
case PCIB_IVAR_DOMAIN:
*result = 0;
return 0;
case PCIB_IVAR_BUS:
*result = legacy_get_pcibus(dev);
return 0;
}
return ENOENT;
}
int
legacy_pcib_write_ivar(device_t dev, device_t child, int which,
uintptr_t value)
{
switch (which) {
case PCIB_IVAR_DOMAIN:
return EINVAL;
case PCIB_IVAR_BUS:
legacy_set_pcibus(dev, value);
return 0;
}
return ENOENT;
}
/*
* Helper routine for x86 Host-PCI bridge driver resource allocation.
* This is used to adjust the start address of wildcard allocation
* requests to avoid low addresses that are known to be problematic.
*
* If no memory preference is given, use upper 32MB slot most BIOSes
* use for their memory window. This is typically only used on older
* laptops that don't have PCI busses behind a PCI bridge, so assuming
* > 32MB is likely OK.
*
* However, this can cause problems for other chipsets, so we make
* this tunable by hw.pci.host_mem_start.
*/
SYSCTL_DECL(_hw_pci);
static unsigned long host_mem_start = 0x80000000;
SYSCTL_ULONG(_hw_pci, OID_AUTO, host_mem_start, CTLFLAG_RDTUN, &host_mem_start,
0, "Limit the host bridge memory to being above this address.");
u_long
hostb_alloc_start(int type, u_long start, u_long end, u_long count)
{
if (start + count - 1 != end) {
if (type == SYS_RES_MEMORY && start < host_mem_start)
start = host_mem_start;
if (type == SYS_RES_IOPORT && start < 0x1000)
start = 0x1000;
}
return (start);
}
struct resource *
legacy_pcib_alloc_resource(device_t dev, device_t child, int type, int *rid,
u_long start, u_long end, u_long count, u_int flags)
{
#if defined(NEW_PCIB) && defined(PCI_RES_BUS)
if (type == PCI_RES_BUS)
return (pci_domain_alloc_bus(0, child, rid, start, end, count,
flags));
#endif
start = hostb_alloc_start(type, start, end, count);
return (bus_generic_alloc_resource(dev, child, type, rid, start, end,
count, flags));
}
#if defined(NEW_PCIB) && defined(PCI_RES_BUS)
int
legacy_pcib_adjust_resource(device_t dev, device_t child, int type,
struct resource *r, u_long start, u_long end)
{
if (type == PCI_RES_BUS)
return (pci_domain_adjust_bus(0, child, r, start, end));
return (bus_generic_adjust_resource(dev, child, type, r, start, end));
}
int
legacy_pcib_release_resource(device_t dev, device_t child, int type, int rid,
struct resource *r)
{
if (type == PCI_RES_BUS)
return (pci_domain_release_bus(0, child, rid, r));
return (bus_generic_release_resource(dev, child, type, rid, r));
}
#endif
static device_method_t legacy_pcib_methods[] = {
/* Device interface */
DEVMETHOD(device_identify, legacy_pcib_identify),
DEVMETHOD(device_probe, legacy_pcib_probe),
DEVMETHOD(device_attach, legacy_pcib_attach),
DEVMETHOD(device_shutdown, bus_generic_shutdown),
DEVMETHOD(device_suspend, bus_generic_suspend),
DEVMETHOD(device_resume, bus_generic_resume),
/* Bus interface */
DEVMETHOD(bus_read_ivar, legacy_pcib_read_ivar),
DEVMETHOD(bus_write_ivar, legacy_pcib_write_ivar),
DEVMETHOD(bus_alloc_resource, legacy_pcib_alloc_resource),
#if defined(NEW_PCIB) && defined(PCI_RES_BUS)
DEVMETHOD(bus_adjust_resource, legacy_pcib_adjust_resource),
DEVMETHOD(bus_release_resource, legacy_pcib_release_resource),
#else
DEVMETHOD(bus_adjust_resource, bus_generic_adjust_resource),
DEVMETHOD(bus_release_resource, bus_generic_release_resource),
#endif
DEVMETHOD(bus_activate_resource, bus_generic_activate_resource),
DEVMETHOD(bus_deactivate_resource, bus_generic_deactivate_resource),
DEVMETHOD(bus_setup_intr, bus_generic_setup_intr),
DEVMETHOD(bus_teardown_intr, bus_generic_teardown_intr),
/* pcib interface */
DEVMETHOD(pcib_maxslots, legacy_pcib_maxslots),
DEVMETHOD(pcib_read_config, legacy_pcib_read_config),
DEVMETHOD(pcib_write_config, legacy_pcib_write_config),
DEVMETHOD(pcib_route_interrupt, legacy_pcib_route_interrupt),
DEVMETHOD(pcib_alloc_msi, legacy_pcib_alloc_msi),
DEVMETHOD(pcib_release_msi, pcib_release_msi),
DEVMETHOD(pcib_alloc_msix, legacy_pcib_alloc_msix),
DEVMETHOD(pcib_release_msix, pcib_release_msix),
DEVMETHOD(pcib_map_msi, legacy_pcib_map_msi),
DEVMETHOD_END
};
static devclass_t hostb_devclass;
DEFINE_CLASS_0(pcib, legacy_pcib_driver, legacy_pcib_methods, 1);
DRIVER_MODULE(pcib, legacy, legacy_pcib_driver, hostb_devclass, 0, 0);
/*
* Install placeholder to claim the resources owned by the
* PCI bus interface. This could be used to extract the
* config space registers in the extreme case where the PnP
* ID is available and the PCI BIOS isn't, but for now we just
* eat the PnP ID and do nothing else.
*
* XXX we should silence this probe, as it will generally confuse
* people.
*/
static struct isa_pnp_id pcibus_pnp_ids[] = {
{ 0x030ad041 /* PNP0A03 */, "PCI Bus" },
{ 0x080ad041 /* PNP0A08 */, "PCIe Bus" },
{ 0 }
};
static int
pcibus_pnp_probe(device_t dev)
{
int result;
if ((result = ISA_PNP_PROBE(device_get_parent(dev), dev, pcibus_pnp_ids)) <= 0)
device_quiet(dev);
return(result);
}
static int
pcibus_pnp_attach(device_t dev)
{
return(0);
}
static device_method_t pcibus_pnp_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, pcibus_pnp_probe),
DEVMETHOD(device_attach, pcibus_pnp_attach),
DEVMETHOD(device_detach, bus_generic_detach),
DEVMETHOD(device_shutdown, bus_generic_shutdown),
DEVMETHOD(device_suspend, bus_generic_suspend),
DEVMETHOD(device_resume, bus_generic_resume),
{ 0, 0 }
};
static devclass_t pcibus_pnp_devclass;
DEFINE_CLASS_0(pcibus_pnp, pcibus_pnp_driver, pcibus_pnp_methods, 1);
DRIVER_MODULE(pcibus_pnp, isa, pcibus_pnp_driver, pcibus_pnp_devclass, 0, 0);
#ifdef __HAVE_PIR
/*
* Provide a PCI-PCI bridge driver for PCI busses behind PCI-PCI bridges
* that appear in the PCIBIOS Interrupt Routing Table to use the routing
* table for interrupt routing when possible.
*/
static int pcibios_pcib_probe(device_t bus);
static device_method_t pcibios_pcib_pci_methods[] = {
/* Device interface */
DEVMETHOD(device_probe, pcibios_pcib_probe),
/* pcib interface */
DEVMETHOD(pcib_route_interrupt, legacy_pcib_route_interrupt),
{0, 0}
};
static devclass_t pcib_devclass;
DEFINE_CLASS_1(pcib, pcibios_pcib_driver, pcibios_pcib_pci_methods,
sizeof(struct pcib_softc), pcib_driver);
DRIVER_MODULE(pcibios_pcib, pci, pcibios_pcib_driver, pcib_devclass, 0, 0);
static int
pcibios_pcib_probe(device_t dev)
{
int bus;
if ((pci_get_class(dev) != PCIC_BRIDGE) ||
(pci_get_subclass(dev) != PCIS_BRIDGE_PCI))
return (ENXIO);
bus = pci_read_config(dev, PCIR_SECBUS_1, 1);
if (bus == 0)
return (ENXIO);
if (!pci_pir_probe(bus, 1))
return (ENXIO);
device_set_desc(dev, "PCIBIOS PCI-PCI bridge");
return (-2000);
}
#endif
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