07 Nov, 2011
2 commits
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* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
Revert "tracing: Include module.h in define_trace.h"
irq: don't put module.h into irq.h for tracking irqgen modules.
bluetooth: macroize two small inlines to avoid module.h
ip_vs.h: fix implicit use of module_get/module_put from module.h
nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
include: replace linux/module.h with "struct module" wherever possible
include: convert various register fcns to macros to avoid include chaining
crypto.h: remove unused crypto_tfm_alg_modname() inline
uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
pm_runtime.h: explicitly requires notifier.h
linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
miscdevice.h: fix up implicit use of lists and types
stop_machine.h: fix implicit use of smp.h for smp_processor_id
of: fix implicit use of errno.h in include/linux/of.h
of_platform.h: delete needless include
acpi: remove module.h include from platform/aclinux.h
miscdevice.h: delete unnecessary inclusion of module.h
device_cgroup.h: delete needless include
net: sch_generic remove redundant use of
net: inet_timewait_sock doesnt need
...Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in
- drivers/media/dvb/frontends/dibx000_common.c
- drivers/media/video/{mt9m111.c,ov6650.c}
- drivers/mfd/ab3550-core.c
- include/linux/dmaengine.h -
* 'trivial' of git://git.kernel.org/pub/scm/linux/kernel/git/mmarek/kbuild:
scsi: drop unused Kconfig symbol
pci: drop unused Kconfig symbol
stmmac: drop unused Kconfig symbol
x86: drop unused Kconfig symbol
powerpc: drop unused Kconfig symbols
powerpc: 40x: drop unused Kconfig symbol
mips: drop unused Kconfig symbols
openrisc: drop unused Kconfig symbols
arm: at91: drop unused Kconfig symbol
samples: drop unused Kconfig symbol
m32r: drop unused Kconfig symbol
score: drop unused Kconfig symbols
sh: drop unused Kconfig symbol
um: drop unused Kconfig symbol
sparc: drop unused Kconfig symbol
alpha: drop unused Kconfig symbolFix up trivial conflict in drivers/net/ethernet/stmicro/stmmac/Kconfig
as per Michal: the STMMAC_DUAL_MAC config variable is still unused and
should be deleted.
01 Nov, 2011
3 commits
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These were getting module.h implicitly from device.h but we want
to clean that up, so we fix it here to avoid things like:pci/slot.c: In function ‘pci_hp_create_module_link’:
pci/slot.c:383: error: ‘module_kset’ undeclared (first use in this function)Similarly, rpadlpar_core.c is modular, so add module.h to its includes.
Signed-off-by: Paul Gortmaker
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They were implicitly getting it from device.h --> module.h but
we want to clean that up. So add the minimal header for these
macros.Signed-off-by: Paul Gortmaker
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There's no other Kconfig symbol that depends on XEN_PCIDEV_FE_DEBUG.
Neither is there anything that uses CONFIG_XEN_PCIDEV_FE_DEBUG.Signed-off-by: Paul Bolle
Reviewed-by: Konrad Rzeszutek Wilk
Signed-off-by: Michal Marek
29 Oct, 2011
1 commit
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* 'next-rebase' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci:
PCI: Clean-up MPS debug output
pci: Clamp pcie_set_readrq() when using "performance" settings
PCI: enable MPS "performance" setting to properly handle bridge MPS
PCI: Workaround for Intel MPS errata
PCI: Add support for PASID capability
PCI: Add implementation for PRI capability
PCI: Export ATS functions to modules
PCI: Move ATS implementation into own file
PCI / PM: Remove unnecessary error variable from acpi_dev_run_wake()
PCI hotplug: acpiphp: Prevent deadlock on PCI-to-PCI bridge remove
PCI / PM: Extend PME polling to all PCI devices
PCI quirk: mmc: Always check for lower base frequency quirk for Ricoh 1180:e823
PCI: Make pci_setup_bridge() non-static for use by arch code
x86: constify PCI raw ops structures
PCI: Add quirk for known incorrect MPSS
PCI: Add Solarflare vendor ID and SFC4000 device IDs
28 Oct, 2011
4 commits
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Clean-up MPS debug output to make it a single line and aligned, thus
making it more readable for a large number of buses and devices in a
single system.Suggested by Benjamin Herrenschmidt
Signed-off-by: Jon Mason
Signed-off-by: Jesse Barnes -
When configuring the PCIe settings for "performance", we allow parents
to have a larger Max Payload Size than children and rely on children
Max Read Request Size to not be larger than their own MPS to avoid
having the host bridge generate responses they can't cope with.However, various drivers in Linux call pci_set_readrq() with arbitrary
values, assuming this to be a simple performance tweak. This breaks
under our "performance" configuration.Fix that by making sure the value programmed by pcie_set_readrq() is
never larger than the configured MPS for that device.Signed-off-by: Benjamin Herrenschmidt
Signed-off-by: Jon Mason
Signed-off-by: Jesse Barnes -
Rework the "performance" MPS option to configure the device MPS with the
smaller of the device MPSS or the bridge MPS (which is assumed to be
properly configured at this point to the largest allowable MPS based on
its parent bus).Also, rework the MRRS setting to report an inability to set the MRRS to
a valid setting.Signed-off-by: Jon Mason
Acked-by: Benjamin Herrenschmidt
Signed-off-by: Jesse Barnes -
Intel 5000 and 5100 series memory controllers have a known issue if read
completion coalescing is enabled and the PCI-E Maximum Payload Size is
set to 256B. To work around this issue, disable read completion
coalescing in the memory controller and root complexes. Unfortunately,
it must always be disabled, even if no 256B MPS devices are present, due
to the possibility of one being hotplugged.Links to erratas:
http://www.intel.com/content/dam/doc/specification-update/5000-chipset-memory-controller-hub-specification-update.pdf
http://www.intel.com/content/dam/doc/specification-update/5100-memory-controller-hub-chipset-specification-update.pdfThanks to Jesse Brandeburg and Ben Hutchings for providing insight into
the problem.Tested-and-Reported-by: Avi Kivity
Signed-off-by: Jon Mason
Signed-off-by: Jesse Barnes
26 Oct, 2011
1 commit
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* 'core-iommu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, ioapic: Consolidate the explicit EOI code
x86, ioapic: Restore the mask bit correctly in eoi_ioapic_irq()
x86, kdump, ioapic: Reset remote-IRR in clear_IO_APIC
iommu: Rename the DMAR and INTR_REMAP config options
x86, ioapic: Define irq_remap_modify_chip_defaults()
x86, msi, intr-remap: Use the ioapic set affinity routine
iommu: Cleanup ifdefs in detect_intel_iommu()
iommu: No need to set dmar_disabled in check_zero_address()
iommu: Move IOMMU specific code to intel-iommu.c
intr_remap: Call dmar_dev_scope_init() explicitly
x86, x2apic: Enable the bios request for x2apic optout
25 Oct, 2011
1 commit
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…ci.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen
* 'stable/drivers-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xenbus: don't rely on xen_initial_domain to detect local xenstore
xenbus: Fix loopback event channel assuming domain 0
xen/pv-on-hvm:kexec: Fix implicit declaration of function 'xen_hvm_domain'
xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel
xen/pv-on-hvm kexec: update xs_wire.h:xsd_sockmsg_type from xen-unstable
xen/pv-on-hvm kexec+kdump: reset PV devices in kexec or crash kernel
xen/pv-on-hvm kexec: rebind virqs to existing eventchannel ports
xen/pv-on-hvm kexec: prevent crash in xenwatch_thread() when stale watch events arrive* 'stable/drivers.bugfixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pciback: Check if the device is found instead of blindly assuming so.
xen/pciback: Do not dereference psdev during printk when it is NULL.
xen: remove XEN_PLATFORM_PCI config option
xen: XEN_PVHVM depends on PCI
xen/pciback: double lock typo
xen/pciback: use mutex rather than spinlock in vpci backend
xen/pciback: Use mutexes when working with Xenbus state transitions.
xen/pciback: miscellaneous adjustments
xen/pciback: use mutex rather than spinlock in passthrough backend
xen/pciback: use resource_size()* 'stable/pci.fixes-3.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/xen:
xen/pci: support multi-segment systems
xen-swiotlb: When doing coherent alloc/dealloc check before swizzling the MFNs.
xen/pci: make bus notifier handler return sane values
xen-swiotlb: fix printk and panic args
xen-swiotlb: Fix wrong panic.
xen-swiotlb: Retry up three times to allocate Xen-SWIOTLB
xen-pcifront: Update warning comment to use 'e820_host' option.
15 Oct, 2011
10 commits
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Devices supporting Process Address Space Identifiers
(PASIDs) can use an IOMMU to access multiple IO address
spaces at the same time. A PCIe device indicates support for
this feature by implementing the PASID capability. This
patch adds support for the capability to the Linux kernel.Reviewed-by: Bjorn Helgaas
Signed-off-by: Joerg Roedel
Signed-off-by: Jesse Barnes -
Implement the necessary functions to handle PRI capabilities
on PCIe devices. With PRI devices behind an IOMMU can signal
page fault conditions to software and recover from such
faults.Reviewed-by: Bjorn Helgaas
Signed-off-by: Joerg Roedel
Signed-off-by: Jesse Barnes -
This patch makes the ATS functions usable for modules.
They will be used by a module implementing some advanced
AMD IOMMU features.Reviewed-by: Bjorn Helgaas
Signed-off-by: Joerg Roedel
Signed-off-by: Jesse Barnes -
ATS does not depend on IOV support, so move the code into
its own file. This file will also include support for the
PRI and PASID capabilities later.
Also give ATS its own Kconfig variable to allow selecting it
without IOV support.Reviewed-by: Bjorn Helgaas
Signed-off-by: Joerg Roedel
Signed-off-by: Jesse Barnes -
The result returned by acpi_dev_run_wake() is always either -EINVAL
or -ENODEV, while obviously it should return 0 on success. The
problem is that the leftover error variable, that's not really used
in the function, is initialized with -ENODEV and then returned
without modification.To fix this issue remove the error variable from acpi_dev_run_wake()
and make the function return 0 on success as appropriate.Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
I originally submitted a patch to workaround this by pushing all Ejection
Requests and Device Checks onto the kacpi_hotplug queue.http://marc.info/?l=linux-acpi&m=131678270930105&w=2
The patch is still insufficient in that Bus Checks also need to be added.
Rather than add all events, including non-PCI-hotplug events, to the
hotplug queue, mjg suggested that a better approach would be to modify
the acpiphp driver so only acpiphp events would be added to the
kacpi_hotplug queue.It's a longer patch, but at least we maintain the benefit of having separate
queues in ACPI. This, of course, is still only a workaround the problem.
As Bjorn and mjg pointed out, we have to refactor a lot of this code to do
the right thing but at this point it is a better to have this code working.The acpi core places all events on the kacpi_notify queue. When the acpiphp
driver is loaded and a PCI card with a PCI-to-PCI bridge is removed the
following call sequence occurs:cleanup_p2p_bridge()
-> cleanup_bridge()
-> acpi_remove_notify_handler()
-> acpi_os_wait_events_complete()
-> flush_workqueue(kacpi_notify_wq)which is the queue we are currently executing on and the process will hang.
Move all hotplug acpiphp events onto the kacpi_hotplug workqueue. In
handle_hotplug_event_bridge() and handle_hotplug_event_func() we can simply
push the rest of the work onto the kacpi_hotplug queue and then avoid the
deadlock.Signed-off-by: Prarit Bhargava
Cc: mjg@redhat.com
Cc: bhelgaas@google.com
Cc: linux-acpi@vger.kernel.org
Signed-off-by: Jesse Barnes -
The land of PCI power management is a land of sorrow and ugliness,
especially in the area of signaling events by devices. There are
devices that set their PME Status bits, but don't really bother
to send a PME message or assert PME#. There are hardware vendors
who don't connect PME# lines to the system core logic (they know
who they are). There are PCI Express Root Ports that don't bother
to trigger interrupts when they receive PME messages from the devices
below. There are ACPI BIOSes that forget to provide _PRW methods for
devices capable of signaling wakeup. Finally, there are BIOSes that
do provide _PRW methods for such devices, but then don't bother to
call Notify() for those devices from the corresponding _Lxx/_Exx
GPE-handling methods. In all of these cases the kernel doesn't have
a chance to receive a proper notification that it should wake up a
device, so devices stay in low-power states forever. Worse yet, in
some cases they continuously send PME Messages that are silently
ignored, because the kernel simply doesn't know that it should clear
the device's PME Status bit.This problem was first observed for "parallel" (non-Express) PCI
devices on add-on cards and Matthew Garrett addressed it by adding
code that polls PME Status bits of such devices, if they are enabled
to signal PME, to the kernel. Recently, however, it has turned out
that PCI Express devices are also affected by this issue and that it
is not limited to add-on devices, so it seems necessary to extend
the PME polling to all PCI devices, including PCI Express and planar
ones. Still, it would be wasteful to poll the PME Status bits of
devices that are known to receive proper PME notifications, so make
the kernel (1) poll the PME Status bits of all PCI and PCIe devices
enabled to signal PME and (2) disable the PME Status polling for
devices for which correct PME notifications are received.Tested-by: Sarah Sharp
Signed-off-by: Rafael J. Wysocki
Signed-off-by: Jesse Barnes -
Commit 15bed0f2f added a quirk for the e823 Ricoh card reader to lower the
base frequency. However, the quirk first checks to see if the proprietary
MMC controller is disabled, and returns if so. On some devices, such as the
Lenovo X220, the MMC controller is already disabled by firmware it seems,
but the frequency change is still needed so sdhci-pci can talk to the cards.
Since the MMC controller is disabled, the frequency fixup was never being run
on these machines.This moves the e823 check above the MMC controller check so that it always
gets run.This fixes https://bugzilla.redhat.com/show_bug.cgi?id=722509
Signed-off-by: Josh Boyer
Signed-off-by: Jesse Barnes -
The "powernv" platform of the powerpc architecture needs to assign PCI
resources using a specific algorithm to fit some HW constraints of
the IBM "IODA" architecture (related to the ability to create error
handling domains that encompass specific segments of MMIO space).For doing so, it wants to call pci_setup_bridge() from architecture
specific resource management in order to configure bridges after all
resources have been assigned. So make it non-static.Signed-off-by: Benjamin Herrenschmidt
Signed-off-by: Jesse Barnes -
Using legacy interrupts and TLPs > 256 bytes on the SFC4000 (all
revisions) may cause interrupt messages to be replayed. In some
systems this results in a non-recoverable MCE. Early boards using the
SFC4000 set the maximum payload size supported (MPSS) to 1024 bytes
and we should override that.There are probably other devices with similar issues, so give this
quirk a generic name.Signed-off-by: Ben Hutchings
Signed-off-by: Jesse Barnes
05 Oct, 2011
1 commit
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Add the ability to disable PCI-E MPS turning and using the BIOS
configured MPS defaults. Due to the number of issues recently
discovered on some x86 chipsets, make this the default behavior.Also, add the option for peer to peer DMA MPS configuration. Peer to
peer DMA is outside the scope of this patch, but MPS configuration could
prevent it from working by having the MPS on one root port different
than the MPS on another. To work around this, simply make the system
wide MPS the smallest possible value (128B).Signed-off-by: Jon Mason
Acked-by: Benjamin Herrenschmidt
Signed-off-by: Linus Torvalds
21 Sep, 2011
1 commit
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Change the CONFIG_DMAR to CONFIG_INTEL_IOMMU to be consistent
with the other IOMMU options.Rename the CONFIG_INTR_REMAP to CONFIG_IRQ_REMAP to match the
irq subsystem name.And define the CONFIG_DMAR_TABLE for the common ACPI DMAR
routines shared by both CONFIG_INTEL_IOMMU and CONFIG_IRQ_REMAP.Signed-off-by: Suresh Siddha
Cc: yinghai@kernel.org
Cc: youquan.song@intel.com
Cc: joerg.roedel@amd.com
Cc: tony.luck@intel.com
Cc: dwmw2@infradead.org
Link: http://lkml.kernel.org/r/20110824001456.558630224@sbsiddha-desk.sc.intel.com
Signed-off-by: Ingo Molnar
14 Sep, 2011
1 commit
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In pcie_find_smpss(), we have the following statement:
if (dev->is_hotplug_bridge && (!list_is_singular(&dev->bus->devices) ||
dev->bus->self->pcie_type != PCI_EXP_TYPE_ROOT_PORT))The problem is that at least on my machine, this gets called for the
root complex (virtual P2P bridge), and dev->bus->self is NULL since
the parent bus for this is not itself anchor to a PCI device.This adds the necessary NULL check.
Signed-off-by: Benjamin Herrenschmidt
Acked-by: Jon Mason
Signed-off-by: Linus Torvalds
10 Sep, 2011
2 commits
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Modifying the Maximum Read Request Size to 0 (value of 128Bytes) has
massive negative ramifications on some devices. Without knowing which
devices have this issue, do not modify from the default value when
walking the PCI-E bus in pcie_bus_safe mode. Also, make pcie_bus_safe
the default procedure.Tested-by: Sven Schnelle
Tested-by: Simon Kirby
Tested-by: Stephen M. Cameron
Reported-and-tested-by: Eric Dumazet
Reported-and-tested-by: Niels Ole Salscheider
References: https://bugzilla.kernel.org/show_bug.cgi?id=42162
Signed-off-by: Jon Mason
Acked-by: Jesse Barnes
Signed-off-by: Linus Torvalds -
Commit b03e7495a862 ("PCI: Set PCI-E Max Payload Size on fabric")
introduced a potential NULL pointer dereference in calls to
pcie_bus_configure_settings due to attempts to access pci_bus self
variables when the self pointer is NULL.To correct this, verify that the self pointer in pci_bus is non-NULL
before dereferencing it.Reported-by: Stanislaw Gruszka
Signed-off-by: Shyam Iyer
Signed-off-by: Jon Mason
Acked-by: Jesse Barnes
Signed-off-by: Linus Torvalds
27 Aug, 2011
1 commit
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With Xen changeset 23428 "libxl: Add 'e820_host' option to config file"
the E820 as seen from the host can now be passed into the guest.
This means that a PV guest can now:
- Use the correct PCI I/O gap. Before these patches, Linux guest would
boot up and would tell:
[ 0.000000] Allocating PCI resources starting at 40000000 (gap: 40000000:c0000000)
while in actuality the PCI I/O gap should have been:
[ 0.000000] Allocating PCI resources starting at b0000000 (gap: b0000000:4c000000)- The PV domain with PCI devices was limited to 3GB. It now can be booted
with 4GB, 8GB, or whatever number you want. The PCI devices will now _not_ conflict
with System RAM. Meaning the drivers can load.CC: Jesse Barnes
CC: linux-pci@vger.kernel.org
CC: stable@kernel.org
[v2: Made the string less broken up. Suggested by Joe Perches]
Signed-off-by: Konrad Rzeszutek Wilk
21 Aug, 2011
1 commit
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Fix new kernel-doc warning in pci.c:
Warning(drivers/pci/pci.c:3259): No description found for parameter 'mps'
Warning(drivers/pci/pci.c:3259): Excess function parameter 'rq' description in 'pcie_set_mps'Signed-off-by: Randy Dunlap
Cc: Jesse Barnes
Signed-off-by: Linus Torvalds
20 Aug, 2011
1 commit
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* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: OF: Don't crash when bridge parent is NULL.
PCI: export pcie_bus_configure_settings symbol
PCI: code and comments cleanup
PCI: make cardbus-bridge resources optional
PCI: make SRIOV resources optional
PCI : ability to relocate assigned pci-resources
PCI: honor child buses add_size in hot plug configuration
PCI: Set PCI-E Max Payload Size on fabric
19 Aug, 2011
1 commit
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In pcibios_get_phb_of_node(), we will crash while booting if
bus->bridge->parent is NULL.Check for this case and avoid dereferencing the NULL pointer.
Signed-off-by: David Daney
Acked-by: Benjamin Herrenschmidt
Acked-by: Grant Likely
Signed-off-by: Jesse Barnes
03 Aug, 2011
1 commit
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* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (28 commits)
ACPI: delete stale reference in kernel-parameters.txt
ACPI: add missing _OSI strings
ACPI: remove NID_INVAL
thermal: make THERMAL_HWMON implementation fully internal
thermal: split hwmon lookup to a separate function
thermal: hide CONFIG_THERMAL_HWMON
ACPI print OSI(Linux) warning only once
ACPI: DMI workaround for Asus A8N-SLI Premium and Asus A8N-SLI DELUX
ACPI / Battery: propagate sysfs error in acpi_battery_add()
ACPI / Battery: avoid acpi_battery_add() use-after-free
ACPI: introduce "acpi_rsdp=" parameter for kdump
ACPI: constify ops structs
ACPI: fix CONFIG_X86_REROUTE_FOR_BROKEN_BOOT_IRQS
ACPI: fix 80 char overflow
ACPI / Battery: Resolve the race condition in the sysfs_remove_battery()
ACPI / Battery: Add the check before refresh sysfs in the battery_notify()
ACPI / Battery: Add the hibernation process in the battery_notify()
ACPI / Battery: Rename acpi_battery_quirks2 with acpi_battery_quirks
ACPI / Battery: Change 16-bit signed negative battery current into correct value
ACPI / Battery: Add the power unit macro
...
02 Aug, 2011
7 commits
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pcie_bus_configure_settings needs to be exported if the PCI hotplug
driver is being compiled as a module.Reported-by: Stephen Rothwell
Signed-off-by: Jon Mason
Signed-off-by: Jesse Barnes -
a) adjust_resource_sorted() is now called reassign_resource_sorted()
b) nice-to-have is now called optional
c) add_list is now called realloc_list.Signed-off-by: Ram Pai
Signed-off-by: Jesse Barnes -
Allocate resources to cardbus bridge only after all other genuine
resources requests are satisfied. Dont retry if resource allocation
for cardbus-bridges fail.Signed-off-by: Ram Pai
Signed-off-by: Jesse Barnes -
From: Yinghai Lu
Allocate resources to SRIOV BARs only after all other required
resource-requests are satisfied. Dont retry if resource allocation for SRIOV
BARs fail.Signed-off-by: Ram Pai
Signed-off-by: Yinghai Lu
Signed-off-by: Jesse Barnes -
Currently pci-bridges are allocated enough resources to satisfy their immediate
requirements. Any additional resource-requests fail if additional free space,
contiguous to the one already allocated, is not available. This behavior is not
reasonable since sufficient contiguous resources, that can satisfy the request,
are available at a different location.This patch provides the ability to expand and relocate a allocated resource.
v2: Changelog: Fixed size calculation in pci_reassign_resource()
v3: Changelog : Split this patch. The resource.c changes are already
upstream. All the pci driver changes are in here.Signed-off-by: Ram Pai
Signed-off-by: Jesse Barnes -
git commit c8adf9a3e873eddaaec11ac410a99ef6b9656938
"PCI: pre-allocate additional resources to devices only after
successful allocation of essential resources."fails to take into consideration the optional-resources needed by children
devices while calculating the optional-resource needed by the bridge.This can be a problem on some setup. For example, if a hotplug bridge has 8
children hotplug bridges, the bridge should have enough resources to accomodate
the hotplug requirements for each of its children hotplug bridges. Currently
this is not the case.This patch fixes the problem.
Signed-off-by: Yinghai Lu
Reviewed-by: Ram Pai
Signed-off-by: Jesse Barnes -
On a given PCI-E fabric, each device, bridge, and root port can have a
different PCI-E maximum payload size. There is a sizable performance
boost for having the largest possible maximum payload size on each PCI-E
device. However, if improperly configured, fatal bus errors can occur.
Thus, it is important to ensure that PCI-E payloads sends by a device
are never larger than the MPS setting of all devices on the way to the
destination.This can be achieved two ways:
- A conservative approach is to use the smallest common denominator of
the entire tree below a root complex for every device on that fabric.This means for example that having a 128 bytes MPS USB controller on one
leg of a switch will dramatically reduce performances of a video card or
10GE adapter on another leg of that same switch.It also means that any hierarchy supporting hotplug slots (including
expresscard or thunderbolt I suppose, dbl check that) will have to be
entirely clamped to 128 bytes since we cannot predict what will be
plugged into those slots, and we cannot change the MPS on a "live"
system.- A more optimal way is possible, if it falls within a couple of
constraints:
* The top-level host bridge will never generate packets larger than the
smallest TLP (or if it can be controlled independently from its MPS at
least)
* The device will never generate packets larger than MPS (which can be
configured via MRRS)
* No support of direct PCI-E PCI-E transfers between devices without
some additional code to specifically deal with that caseThen we can use an approach that basically ignores downstream requests
and focuses exclusively on upstream requests. In that case, all we need
to care about is that a device MPS is no larger than its parent MPS,
which allows us to keep all switches/bridges to the max MPS supported by
their parent and eventually the PHB.In this case, your USB controller would no longer "starve" your 10GE
Ethernet and your hotplug slots won't affect your global MPS.
Additionally, the hotplugged devices themselves can be configured to a
larger MPS up to the value configured in the hotplug bridge.To choose between the two available options, two PCI kernel boot args
have been added to the PCI calls. "pcie_bus_safe" will provide the
former behavior, while "pcie_bus_perf" will perform the latter behavior.
By default, the latter behavior is used.NOTE: due to the location of the enablement, each arch will need to add
calls to this function. This patch only enables x86.This patch includes a number of changes recommended by Benjamin
Herrenschmidt.Tested-by: Jordan_Hargrave@dell.com
Signed-off-by: Jon Mason
Signed-off-by: Jesse Barnes
30 Jul, 2011
1 commit
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* 'linux-next' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
PCI: remove printks about disabled bridge windows
PCI: fold pci_calc_resource_flags() into decode_bar()
PCI: treat mem BAR type "11" (reserved) as 32-bit, not 64-bit, BAR
PCI: correct pcie_set_readrq write size
PCI: pciehp: change wait time for valid configuration access
x86/PCI: Preserve existing pci=bfsort whitelist for Dell systems
PCI: ARI is a PCIe v2 feature
x86/PCI: quirks: Use pci_dev->revision
PCI: Make the struct pci_dev * argument of pci_fixup_irqs const.
PCI hotplug: cpqphp: use pci_dev->vendor
PCI hotplug: cpqphp: use pci_dev->subsystem_{vendor|device}
x86/PCI: config space accessor functions should not ignore the segment argument
PCI: Assign values to 'pci_obff_signal_type' enumeration constants
x86/PCI: reduce severity of host bridge window conflict warnings
PCI: enumerate the PCI device only removed out PCI hieratchy of OS when re-scanning PCI
PCI: PCIe AER: add aer_recover_queue
x86/PCI: select direct access mode for mmconfig option
PCI hotplug: Rename is_ejectable which also exists in dock.c