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path: root/drivers/pci/hotplug/pciehp.h
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2018-10-02PCI: pciehp: Disable hotplug interrupt during suspendMika Westerberg
When PCIe hotplug port is transitioned into D3hot, the link to the downstream component will go down. If hotplug interrupt generation is enabled when that happens, it will trigger immediately, waking up the system and bringing the link back up. To prevent this, disable hotplug interrupt generation when system suspend is entered. This does not prevent wakeup from low power states according to PCIe 4.0 spec section 6.7.3.4: Software enables a hot-plug event to generate a wakeup event by enabling software notification of the event as described in Section 6.7.3.1. Note that in order for software to disable interrupt generation while keeping wakeup generation enabled, the Hot-Plug Interrupt Enable bit must be cleared. So as long as we have set the slot event mask accordingly, wakeup should work even if slot interrupt is disabled. The port should trigger wake and then send PME to the root port when the PCIe hierarchy is brought back up. Limit this to systems using native PME mechanism to make sure older Apple systems depending on commit e3354628c376 ("PCI: pciehp: Support interrupts sent from D3hot") still continue working. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-10-02PCI: Make link active reporting detection genericKeith Busch
The spec has timing requirements when waiting for a link to become active after a conventional reset. Implement those hard delays when waiting for an active link so pciehp and dpc drivers don't need to duplicate this. For devices that don't support data link layer active reporting, wait the fixed time recommended by the PCIe spec. Signed-off-by: Keith Busch <keith.busch@intel.com> [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Sinan Kaya <okaya@kernel.org>
2018-09-18PCI: hotplug: Embed hotplug_slotLukas Wunner
When the PCI hotplug core and its first user, cpqphp, were introduced in February 2002 with historic commit a8a2069f432c, cpqphp allocated a slot struct for its internal use plus a hotplug_slot struct to be registered with the hotplug core and linked the two with pointers: https://git.kernel.org/tglx/history/c/a8a2069f432c Nowadays, the predominant pattern in the tree is to embed ("subclass") such structures in one another and cast to the containing struct with container_of(). But it wasn't until July 2002 that container_of() was introduced with historic commit ec4f214232cf: https://git.kernel.org/tglx/history/c/ec4f214232cf pnv_php, introduced in 2016, did the right thing and embedded struct hotplug_slot in its internal struct pnv_php_slot, but all other drivers cargo-culted cpqphp's design and linked separate structs with pointers. Embedding structs is preferrable to linking them with pointers because it requires fewer allocations, thereby reducing overhead and simplifying error paths. Casting an embedded struct to the containing struct becomes a cheap subtraction rather than a dereference. And having fewer pointers reduces the risk of them pointing nowhere either accidentally or due to an attack. Convert all drivers to embed struct hotplug_slot in their internal slot struct. The "private" pointer in struct hotplug_slot thereby becomes unused, so drop it. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Acked-by: Tyrel Datwyler <tyreld@linux.vnet.ibm.com> # drivers/pci/hotplug/rpa* Acked-by: Sebastian Ott <sebott@linux.ibm.com> # drivers/pci/hotplug/s390* Acked-by: Andy Shevchenko <andy.shevchenko@gmail.com> # drivers/platform/x86 Cc: Len Brown <lenb@kernel.org> Cc: Scott Murray <scott@spiteful.org> Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org> Cc: Paul Mackerras <paulus@samba.org> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Oliver OHalloran <oliveroh@au1.ibm.com> Cc: Gavin Shan <gwshan@linux.vnet.ibm.com> Cc: Gerald Schaefer <gerald.schaefer@de.ibm.com> Cc: Corentin Chary <corentin.chary@gmail.com> Cc: Darren Hart <dvhart@infradead.org>
2018-09-18PCI: pciehp: Reshuffle controller struct for clarityLukas Wunner
The members in pciehp's controller struct are arranged in a seemingly arbitrary order and have grown to an amount that I no longer consider easily graspable by contributors. Sort the members into 5 rubrics: * Slot Capabilities register and quirks * Slot Control register access * Slot Status register event handling * state machine * hotplug core interface Obviously, this is just my personal bikeshed color and if anyone has a better idea, please come forward. Any ordering will do as long as the information is presented in a manageable manner. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-18PCI: pciehp: Rename controller struct members for clarityLukas Wunner
Of the members which were just moved from pciehp's slot struct to the controller struct, rename "lock" to "state_lock" and rename "work" to "button_work" for clarity. Perform the rename separately to the unification of the two structs per Sinan's request. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Sinan Kaya <okaya@kernel.org>
2018-09-18PCI: pciehp: Unify controller and slot structsLukas Wunner
pciehp was originally introduced together with shpchp in a single commit, c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI Express hot-plug drivers"): https://git.kernel.org/tglx/history/c/c16b4b14d980 shpchp supports up to 31 slots per controller, hence uses separate slot and controller structs. pciehp has a 1:1 relationship between slot and controller and therefore never required this separation. Nevertheless, because much of the code had been copy-pasted between the two drivers, pciehp likewise uses separate structs to this very day. The artificial separation of data structures adds unnecessary complexity and bloat to pciehp and requires constantly chasing pointers at runtime. Simplify the driver by merging struct slot into struct controller. Merge the slot constructor pcie_init_slot() and the destructor pcie_cleanup_slot() into the controller counterparts. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-18PCI: pciehp: Tolerate Presence Detect hardwired to zeroLukas Wunner
The WiGig Bus Extension (WBE) specification allows tunneling PCIe over IEEE 802.11. A product implementing this spec is the wil6210 from Wilocity (now part of Qualcomm Atheros). It integrates a PCIe switch with a wireless network adapter: 00.0-+ [1ae9:0101] Upstream Port +-00.0-+ [1ae9:0200] Downstream Port | +-00.0 [168c:0034] Atheros AR9462 Wireless Network Adapter +-02.0 [1ae9:0201] Downstream Port +-03.0 [1ae9:0201] Downstream Port Wirelessly attached devices presumably appear below the hotplug ports with device ID [1ae9:0201]. Oddly, the Downstream Port [1ae9:0200] leading to the wireless network adapter is likewise Hotplug Capable, but has its Presence Detect State bit hardwired to zero. Even if the Link Active bit is set, Presence Detect is zero, so this cannot be caused by in-band presence detection but only by broken hardware. pciehp assumes an empty slot if Presence Detect State is zero, regardless of Link Active being one. Consequently, up until v4.18 it removes the wireless network adapter in pciehp_resume(). From v4.19 it already does so in pciehp_probe(). Be lenient towards broken hardware and assume the slot is occupied if Link Active is set: Introduce pciehp_card_present_or_link_active() and use it in lieu of pciehp_get_adapter_status() everywhere, except in pciehp_handle_presence_or_link_change() whose log messages depend on which of Presence Detect State or Link Active is set. Remove the Presence Detect State check from __pciehp_enable_slot() because it is only called if either of Presence Detect State or Link Active is set. Caution: There is a possibility that broken hardware exists which has working Presence Detect but hardwires Link Active to one. On such hardware the slot will now incorrectly be considered always occupied. If such hardware is discovered, this commit can be rolled back and a quirk can be added which sets is_hotplug_bridge = 0 for [1ae9:0200]. Link: https://bugzilla.kernel.org/show_bug.cgi?id=200839 Reported-and-tested-by: David Yang <mmyangfl@gmail.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Rajat Jain <rajatja@google.com> Cc: Ashok Raj <ashok.raj@intel.com>
2018-09-17PCI: pciehp: Drop hotplug_slot_ops wrappersLukas Wunner
pciehp's ->enable_slot, ->disable_slot, ->get_attention_status and ->reset_slot callbacks are currently implemented by wrapper functions that do nothing else but call down to a backend function. The backends are not called from anywhere else, so drop the wrappers and use the backends directly as callbacks, thereby shaving off a few lines of unnecessary code. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-17PCI: pciehp: Drop unnecessary includesLukas Wunner
Drop the following includes from pciehp source files which no longer use any of the included symbols: * <linux/sched/signal.h> in pciehp.h <linux/signal.h> in pciehp_hpc.c Added by commit de25968cc87c ("fix more missing includes") to accommodate for a call to signal_pending(). The call was removed by commit 262303fe329a ("pciehp: fix wait command completion"). * <linux/interrupt.h> in pciehp_core.c Added by historic commit f308a2dfbe63 ("PCI: add PCI Express Port Bus Driver subsystem") to accommodate for a call to free_irq(): https://git.kernel.org/tglx/history/c/f308a2dfbe63 The call was removed by commit 407f452b05f9 ("pciehp: remove unnecessary free_irq"). * <linux/time.h> in pciehp_core.c and pciehp_hpc.c Added by commit 34d03419f03b ("PCIEHP: Add Electro Mechanical Interlock (EMI) support to the PCIE hotplug driver."), which was reverted by commit bd3d99c17039 ("PCI: Remove untested Electromechanical Interlock (EMI) support in pciehp."). * <linux/module.h> in pciehp_ctrl.c, pciehp_hpc.c and pciehp_pci.c Added by historic commit c16b4b14d980 ("PCI Hotplug: Add SHPC and PCI Express hot-plug drivers"): https://git.kernel.org/tglx/history/c/c16b4b14d980 Module-related symbols were neither used back then in those files, nor are they used today. * <linux/slab.h> in pciehp_ctrl.c Added by commit 5a0e3ad6af86 ("include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h") to accommodate for calls to kmalloc(). The calls were removed by commit 0e94916e6091 ("PCI: pciehp: Handle events synchronously"). * "../pci.h" in pciehp_ctrl.c Added by historic commit 67f4660b72f2 ("PCI: ASPM patch for") to accommodate for usage of the global variable pcie_mch_quirk: https://git.kernel.org/tglx/history/c/67f4660b72f2 The global variable was removed by commit 0ba379ec0fb1 ("PCI: Simplify hotplug mch quirk"). Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-17PCI: pciehp: Differentiate between surprise and safe removalLukas Wunner
When removing PCI devices below a hotplug bridge, pciehp marks them as disconnected if the card is no longer present in the slot or it quiesces them if the card is still present (by disabling INTx interrupts, bus mastering and SERR# reporting). To detect whether the card is still present, pciehp checks the Presence Detect State bit in the Slot Status register. The problem with this approach is that even if the card is present, the link to it may be down, and it that case it would be better to mark the devices as disconnected instead of trying to quiesce them. Moreover, if the card in the slot was quickly replaced by another one, the Presence Detect State bit would be set, yet trying to quiesce the new card's devices would be wrong and the correct thing to do is to mark the previous card's devices as disconnected. Instead of looking at the Presence Detect State bit, it is better to differentiate whether the card was surprise removed versus safely removed (via sysfs or an Attention Button press). On surprise removal, the devices should be marked as disconnected, whereas on safe removal it is correct to quiesce the devices. The knowledge whether a surprise removal or a safe removal is at hand does exist further up in the call stack: A surprise removal is initiated by pciehp_handle_presence_or_link_change(), a safe removal by pciehp_handle_disable_request(). Pass that information down to pciehp_unconfigure_device() and use it in lieu of the Presence Detect State bit. While there, add kernel-doc to pciehp_unconfigure_device() and pciehp_configure_device(). Tested-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Keith Busch <keith.busch@intel.com>
2018-07-31PCI: pciehp: Support interrupts sent from D3hotLukas Wunner
If a hotplug port is able to send an interrupt, one would naively assume that it is accessible at that moment. After all, if it wouldn't be accessible, i.e. if its parent is in D3hot and the link to the hotplug port is thus down, how should an interrupt come through? It turns out that assumption is wrong at least for Thunderbolt: Even though its parents are in D3hot, a Thunderbolt hotplug port is able to signal interrupts. Because the port's config space is inaccessible and resuming the parents may sleep, the hard IRQ handler has to defer runtime resuming the parents and reading the Slot Status register to the IRQ thread. If the hotplug port uses a level-triggered INTx interrupt, it needs to be masked until the IRQ thread has cleared the signaled events. For simplicity, this commit also masks edge-triggered MSI/MSI-X interrupts. Note that if the interrupt is shared (which can only happen for INTx), other devices are starved from receiving interrupts until the IRQ thread is scheduled, has runtime resumed the hotplug port's parents and has read and cleared the Slot Status register. That delay is dominated by the 10 ms D3hot->D0 transition time of each parent port. The worst case is a Thunderbolt downstream port at the end of a daisy chain: There may be up to six Thunderbolt controllers in-between it and the root port, each comprising an upstream and downstream port, plus its own upstream port. That's 13 x 10 = 130 ms. Possible mitigations are polling the interrupt while it's disabled or reducing the d3_delay of Thunderbolt ports if possible. Open code masking of the interrupt instead of requesting it with the IRQF_ONESHOT flag to minimize the period during which it is masked. (IRQF_ONESHOT unmasks the IRQ only after the IRQ thread has finished.) PCIe r4.0 sec 6.7.3.4 states that "If wake generation is required by the associated form factor specification, a hotplug capable Downstream Port must support generation of a wakeup event (using the PME mechanism) on hotplug events that occur when the system is in a sleep state or the Port is in device state D1, D2, or D3Hot." This would seem to imply that PME needs to be enabled on the hotplug port when it is runtime suspended. pci_enable_wake() currently doesn't enable PME on bridges, it may be necessary to add an exemption for hotplug bridges there. On "Light Ridge" Thunderbolt controllers, the PME_Status bit is not set when an interrupt occurs while the hotplug port is in D3hot, even if PME is enabled. (I've tested this on a Mac and we hardcode the OSC_PCI_EXPRESS_PME_CONTROL bit to 0 on Macs in negotiate_os_control(), modifying it to 1 didn't change the behavior.) (Side note: Section 6.7.3.4 also states that "PME and Hot-Plug Event interrupts (when both are implemented) always share the same MSI or MSI-X vector". That would only seem to apply to Root Ports, however the section never mentions Root Ports, only Downstream Ports. This is explained in the definition of "Downstream Port" in the "Terms and Acronyms" section of the PCIe Base Spec: "The Ports on a Switch that are not the Upstream Port are Downstream Ports. All Ports on a Root Complex are Downstream Ports.") Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Ashok Raj <ashok.raj@intel.com> Cc: Keith Busch <keith.busch@intel.com> Cc: Yinghai Lu <yinghai@kernel.org>
2018-07-31PCI: pciehp: Clear spurious events earlier on resumeLukas Wunner
Thunderbolt hotplug ports that were occupied before system sleep resume with their downstream link in "off" state. Only after the Thunderbolt controller has reestablished the PCIe tunnels does the link go up. As a result, a spurious Presence Detect Changed and/or Data Link Layer State Changed event occurs. The events are not immediately acted upon because tunnel reestablishment happens in the ->resume_noirq phase, when interrupts are still disabled. Also, notification of events may initially be disabled in the Slot Control register when coming out of system sleep and is reenabled in the ->resume_noirq phase through: pci_pm_resume_noirq() pci_pm_default_resume_early() pci_restore_state() pci_restore_pcie_state() It is not guaranteed that the events are acted upon at all: PCIe r4.0, sec 6.7.3.4 says that "a port may optionally send an MSI when there are hot-plug events that occur while interrupt generation is disabled, and interrupt generation is subsequently enabled." Note the "optionally". If an MSI is sent, pciehp will gratuitously turn the slot off and back on once the ->resume_early phase has commenced. If an MSI is not sent, the extant, unacknowledged events in the Slot Status register will prevent future notification of presence or link changes. Commit 13c65840feab ("PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resume") fixed the latter by clearing the events in the ->resume phase. Move this to the ->resume_noirq phase to also fix the gratuitous disable/enablement of the slot. The commit further restored the Slot Control register in the ->resume phase, but that's dispensable because as shown above it's already been done in the ->resume_noirq phase. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
2018-07-31PCI: pciehp: Avoid slot access during resetLukas Wunner
The ->reset_slot callback introduced by commits: 2e35afaefe64 ("PCI: pciehp: Add reset_slot() method") and 06a8d89af551 ("PCI: pciehp: Disable link notification across slot reset") disables notification of Presence Detect Changed and Data Link Layer State Changed events for the duration of a secondary bus reset. However a bus reset not only triggers these events, but may also clear the Presence Detect State bit in the Slot Status register and the Data Link Layer Link Active bit in the Link Status register momentarily. According to Sinan Kaya: "I know for a fact that bus reset clears the Data Link Layer Active bit as soon as link goes down. It gets set again following link up. Presence detect depends on the HW implementation. QDT root ports don't change presence detect for instance since nobody actually removed the card. If an implementation supports in-band presence detect, the answer is yes. As soon as the link goes down, presence detect bit will get cleared until recovery." https://lkml.kernel.org/r/42e72f83-3b24-f7ef-e5bc-290fae99259a@codeaurora.org In-band presence detect is also covered in Table 4-15 in PCIe r4.0, sec 4.2.6. pciehp should therefore ensure that any parts of the driver that access those bits do not run concurrently to a bus reset. The only precaution the commits took to that effect was to halt interrupt polling. They made no effort to drain the slot workqueue, cancel an outstanding Attention Button work, or block slot enable/disable requests via sysfs and in the ->probe hook. Now that pciehp is converted to enable/disable the slot exclusively from the IRQ thread, the only places accessing the two above-mentioned bits are the IRQ thread and the ->probe hook. Add locking to serialize them with a bus reset. This obviates the need to halt interrupt polling. Do not add locking to the ->get_adapter_status sysfs callback to afford users unfettered access to that bit. Use an rw_semaphore in lieu of a regular mutex to allow parallel execution of the non-reset code paths accessing the critical bits, i.e. the IRQ thread and the ->probe hook. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Rajat Jain <rajatja@google.com> Cc: Alex Williamson <alex.williamson@redhat.com> Cc: Sinan Kaya <okaya@kernel.org>
2018-07-23PCI: pciehp: Become resilient to missed eventsLukas Wunner
A hotplug port's Slot Status register does not count how often each type of event occurred, it only records the fact *that* an event has occurred. Previously pciehp queued a work item for each event. But if it missed an event, e.g. removal of a card in-between two back-to-back insertions, it queued up the wrong work item or no work item at all. Commit fad214b0aa72 ("PCI: pciehp: Process all hotplug events before looking for new ones") sought to improve the situation by shrinking the window during which events may be missed. But Stefan Roese reports unbalanced Card present and Link Up events, suggesting that we're still missing events if they occur very rapidly. Bjorn Helgaas responds that he considers pciehp's event handling "baroque" and calls for its simplification and rationalization: https://lkml.kernel.org/r/20180202192045.GA53759@bhelgaas-glaptop.roam.corp.google.com It gets worse once a hotplug port is runtime suspended: The port can signal an interrupt while it and its parents are in D3hot, i.e. while it is inaccessible. By the time we've runtime resumed all parents to D0 and read the port's Slot Status register, we may have missed an arbitrary number of events. Event handling therefore needs to be reworked to become resilient to missed events. Assume that a Presence Detect Changed event has occurred. Consider the following truth table: - Slot is in OFF_STATE and is currently empty. => Do nothing. (The event is trailing a Link Down or we've missed an insertion and subsequent removal.) - Slot is in OFF_STATE and is currently occupied. => Turn the slot on. - Slot is in ON_STATE and is currently empty. => Turn the slot off. - Slot is in ON_STATE and is currently occupied. => Turn the slot off, (Be cautious and assume the card in then back on. the slot isn't the same as before.) This leads to the following simple algorithm: 1 If the slot is in ON_STATE, turn it off unconditionally. 2 If the slot is currently occupied, turn it on. Because those actions are now carried out synchronously, rather than by scheduled work items, pciehp reacts to the *current* situation and missed events no longer matter. Data Link Layer State Changed events can be handled identically to Presence Detect Changed events. Note that in the above truth table, a Link Up trailing a Card present event didn't have to be accounted for: It is filtered out by pciehp_check_link_status(). As for Attention Button Pressed events, PCIe r4.0, sec 6.7.1.5 says: "Once the Power Indicator begins blinking, a 5-second abort interval exists during which a second depression of the Attention Button cancels the operation." In other words, the user can only expect the system to react to a button press after it starts blinking. Missed button presses that occur in-between are irrelevant. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Stefan Roese <sr@denx.de> Cc: Mayurkumar Patel <mayurkumar.patel@intel.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com> Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
2018-07-23PCI: pciehp: Declare pciehp_enable/disable_slot() staticLukas Wunner
No callers of pciehp_enable/disable_slot() outside of pciehp_ctrl.c remain, so declare the functions static. For now this requires forward declarations. Those can be eliminated by reshuffling functions once the ongoing effort to refactor the driver has settled. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Drop enable/disable lockLukas Wunner
Previously slot enablement and disablement could happen concurrently. But now it's under the exclusive control of the IRQ thread, rendering the locking obsolete. Drop it. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Enable/disable exclusively from IRQ threadLukas Wunner
Besides the IRQ thread, there are several other places in the driver which enable or disable the slot: - pciehp_probe() enables the slot if it's occupied and the pciehp_force module parameter is used. - pciehp_resume() enables or disables the slot after system sleep. - pciehp_queue_pushbutton_work() enables or disables the slot after the 5 second delay following an Attention Button press. - pciehp_sysfs_enable_slot() and pciehp_sysfs_disable_slot() enable or disable the slot on sysfs write. This requires locking and complicates pciehp's state machine. A simplification can be achieved by enabling and disabling the slot exclusively from the IRQ thread. Amend the functions listed above to request slot enable/disablement from the IRQ thread by either synthesizing a Presence Detect Changed event or, in the case of a disable user request (via sysfs or an Attention Button press), submitting a newly introduced force disable request. The latter is needed because the slot shall be forced off despite being occupied. For this force disable request, avoid colliding with Slot Status register bits by using a bit number greater than 16. For synchronous execution of requests (on sysfs write), wait for the request to finish and retrieve the result. There can only ever be one sysfs write in flight due to the locking in kernfs_fop_write(), hence there is no risk of returning the result of a different sysfs request to user space. The POWERON_STATE and POWEROFF_STATE is now no longer entered by the above-listed functions, but solely by the IRQ thread when it begins a power transition. Afterwards, it moves to STATIC_STATE. The same applies to canceling the Attention Button work, it likewise becomes an IRQ thread only operation. An immediate consequence is that the POWERON_STATE and POWEROFF_STATE is never observed by the IRQ thread itself, only by functions called in a different context, such as pciehp_sysfs_enable_slot(). So remove handling of these states from pciehp_handle_button_press() and pciehp_handle_link_change() which are exclusively called from the IRQ thread. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Track enable/disable statusLukas Wunner
handle_button_press_event() currently determines whether the slot has been turned on or off by looking at the Power Controller Control bit in the Slot Control register. This assumes that an attention button implies presence of a power controller even though that's not mandated by the spec. Moreover the Power Controller Control bit is unreliable when a power fault occurs (PCIe r4.0, sec 6.7.1.8). This issue has existed since the driver was introduced in 2004. Fix by replacing STATIC_STATE with ON_STATE and OFF_STATE and tracking whether the slot has been turned on or off. This is also a required ingredient to make pciehp resilient to missed events, which is the object of an upcoming commit. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Drop slot workqueueLukas Wunner
Previously the slot workqueue was used to handle events and enable or disable the slot. That's no longer the case as those tasks are done synchronously in the IRQ thread. The slot workqueue is thus merely used to handle a button press after the 5 second delay and only one such work item may be in flight at any given time. A separate workqueue isn't necessary for this simple task, so use the system workqueue instead. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Handle events synchronouslyLukas Wunner
Up until now, pciehp's IRQ handler schedules a work item for each event, which in turn schedules a work item to enable or disable the slot. This double indirection was necessary because sleeping wasn't allowed in the IRQ handler. However it is now that pciehp has been converted to threaded IRQ handling and polling, so handle events synchronously in pciehp_ist() and remove the work item infrastructure (with the exception of work items to handle a button press after the 5 second delay). For link or presence change events, move the register read to determine the current link or presence state behind acquisition of the slot lock to prevent it from becoming stale while the lock is contended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Convert to threaded pollingLukas Wunner
We've just converted pciehp to threaded IRQ handling, but still cannot sleep in pciehp_ist() because the function is also called in poll mode, which runs in softirq context (from a timer). Convert poll mode to a kthread so that pciehp_ist() always runs in task context. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Thomas Gleixner <tglx@linutronix.de>
2018-07-23PCI: pciehp: Convert to threaded IRQLukas Wunner
pciehp's IRQ handler queues up a work item for each event signaled by the hardware. A more modern alternative is to let a long running kthread service the events. The IRQ handler's sole job is then to check whether the IRQ originated from the device in question, acknowledge its receipt to the hardware to quiesce the interrupt and wake up the kthread. One benefit is reduced latency to handle the IRQ, which is a necessity for realtime environments. Another benefit is that we can make pciehp simpler and more robust by handling events synchronously in process context, rather than asynchronously by queueing up work items. pciehp's usage of work items is a historic artifact, it predates the introduction of threaded IRQ handlers by two years. (The former was introduced in 2007 with commit 5d386e1ac402 ("pciehp: Event handling rework"), the latter in 2009 with commit 3aa551c9b4c4 ("genirq: add threaded interrupt handler support").) Convert pciehp to threaded IRQ handling by retrieving the pending events in pciehp_isr(), saving them for later consumption by the thread handler pciehp_ist() and clearing them in the Slot Status register. By clearing the Slot Status (and thereby acknowledging the events) in pciehp_isr(), we can avoid requesting the IRQ with IRQF_ONESHOT, which would have the unpleasant side effect of starving devices sharing the IRQ until pciehp_ist() has finished. pciehp_isr() does not count how many times each event occurred, but merely records the fact *that* an event occurred. If the same event occurs a second time before pciehp_ist() is woken, that second event will not be recorded separately, which is problematic according to commit fad214b0aa72 ("PCI: pciehp: Process all hotplug events before looking for new ones") because we may miss removal of a card in-between two back-to-back insertions. We're about to make pciehp_ist() resilient to missed events. The present commit regresses the driver's behavior temporarily in order to separate the changes into reviewable chunks. This doesn't affect regular slow-motion hotplug, only plug-unplug-plug operations that happen in a timespan shorter than wakeup of the IRQ thread. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Mayurkumar Patel <mayurkumar.patel@intel.com> Cc: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
2018-07-23PCI: pciehp: Document struct slot and struct controllerLukas Wunner
Document the driver's data structures to lower the barrier to entry for contributors. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-07-23PCI: pciehp: Declare pciehp_unconfigure_device() voidLukas Wunner
Since commit 0f4bd8014db5 ("PCI: hotplug: Drop checking of PCI_BRIDGE_ CONTROL in *_unconfigure_device()"), pciehp_unconfigure_device() can no longer fail, so declare it and its sole caller remove_board() void, in keeping with the usual kernel pattern that enablement can fail, but disablement cannot. No functional change intended. Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Mika Westerberg <mika.westerberg@linux.intel.com>
2018-07-23PCI: pciehp: Fix use-after-free on unplugLukas Wunner
When pciehp is unbound (e.g. on unplug of a Thunderbolt device), the hotplug_slot struct is deregistered and thus freed before freeing the IRQ. The IRQ handler and the work items it schedules print the slot name referenced from the freed structure in various informational and debug log messages, each time resulting in a quadruple dereference of freed pointers (hotplug_slot -> pci_slot -> kobject -> name). At best the slot name is logged as "(null)", at worst kernel memory is exposed in logs or the driver crashes: pciehp 0000:10:00.0:pcie204: Slot((null)): Card not present An attacker may provoke the bug by unplugging multiple devices on a Thunderbolt daisy chain at once. Unplugging can also be simulated by powering down slots via sysfs. The bug is particularly easy to trigger in poll mode. It has been present since the driver's introduction in 2004: https://git.kernel.org/tglx/history/c/c16b4b14d980 Fix by rearranging teardown such that the IRQ is freed first. Run the work items queued by the IRQ handler to completion before freeing the hotplug_slot struct by draining the work queue from the ->release_slot callback which is invoked by pci_hp_deregister(). Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: stable@vger.kernel.org # v2.6.4
2018-05-23PCI: pciehp: Clear Presence Detect and Data Link Layer Status Changed on resumeMika Westerberg
After a suspend/resume cycle the Presence Detect or Data Link Layer Status Changed bits might be set. If we don't clear them those events will not fire anymore and nothing happens for instance when a device is now hot-unplugged. Fix this by clearing those bits in a newly introduced function pcie_reenable_notification(). This should be fine because immediately after, we check if the adapter is still present by reading directly from the status register. Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: stable@vger.kernel.org
2018-03-09PCI/portdrv: Merge pcieport_if.h into portdrv.hBjorn Helgaas
pcieport_if.h contained the interfaces to register port service driver, e.g., pcie_port_service_register(). portdrv.h contained internal data structures of the port driver. I don't think it's worth keeping those files separate, since both headers and their users are all inside the PCI core. Merge pcieport_if.h directly in drivers/pci/pcie/portdrv.h and update the users to include that instead. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Christoph Hellwig <hch@lst.de>
2018-02-22PCI/portdrv: Move pcieport_if.h to drivers/pci/pcie/Frederick Lawler
Move pcieport_if.h from include/linux to drivers/pci/pcie/pcieport_if.h because the interfaces there are only used by the PCI core. Replace all uses of #include<linux/pcieport_if.h> with relative paths to the new file location, e.g., #include "../pcieport_if.h" Signed-off-by: Frederick Lawler <fred@fredlawl.com> Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
2018-01-28PCI: Add SPDX GPL-2.0+ to replace GPL v2 or later boilerplateBjorn Helgaas
Add SPDX GPL-2.0+ to all PCI files that specified the GPL and allowed either GPL version 2 or any later version. Remove the boilerplate GPL version 2 or later language, relying on the assertion in b24413180f56 ("License cleanup: add SPDX GPL-2.0 license identifier to files with no license") that the SPDX identifier may be used instead of the full boilerplate text. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-09-22PCI: pciehp: Allow exclusive userspace control of indicatorsKeith Busch
PCIe hotplug supports optional Attention and Power Indicators, which are used internally by pciehp. Users can't control the Power Indicator, but they can control the Attention Indicator by writing to a sysfs "attention" file. The Slot Control register has two bits for each indicator, and the PCIe spec defines the encodings for each as (Reserved/On/Blinking/Off). For sysfs "attention" writes, pciehp_set_attention_status() maps into these encodings, so the only useful write values are 0 (Off), 1 (On), and 2 (Blinking). However, some platforms use all four bits for platform-specific indicators, and they need to allow direct user control of them while preventing pciehp from using them at all. Add a "hotplug_user_indicators" flag to the pci_dev structure. When set, pciehp does not use either the Attention Indicator or the Power Indicator, and the low four bits (values 0x0 - 0xf) of sysfs "attention" write values are written directly to the Attention Indicator Control and Power Indicator Control fields. [bhelgaas: changelog, rename flag and accessors to s/attention/indicator/] Signed-off-by: Keith Busch <keith.busch@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-01-08PCI: Fix all whitespace issuesBogicevic Sasa
Fix all whitespace issues (missing or needed whitespace) in all files in drivers/pci. Code is compiled with allyesconfig before and after code changes and objects are recorded and checked with objdiff and they are not changed after this commit. Signed-off-by: Bogicevic Sasa <brutallesale@gmail.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-08-10PCI: pciehp: Remove ignored MRL sensor interrupt eventsBjorn Helgaas
We queued interrupt events for the MRL being opened or closed, but the code in interrupt_event_handler() that handles these events ignored them. Stop enabling MRL interrupts and remove the ignored events. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-08-10PCI: pciehp: Remove unused interrupt eventsBjorn Helgaas
The list of interrupt events (INT_BUTTON_IGNORE, INT_PRESENCE_ON, etc.) was copied from other hotplug drivers, but pciehp doesn't use them all. Remove the interrupt events that aren't used by pciehp. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-06-18PCI: pciehp: Inline the "handle event" functions into the ISRBjorn Helgaas
The pciehp_handle_*() functions (pciehp_handle_attention_button(), etc.) only contain a line or two of useful code, so it's clumsy to put them in separate functions. All they so is add an event to a work queue, and it's clearer to see that directly in the ISR. Inline them directly into pcie_isr(). No functional change. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rajat Jain <rajatja@google.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2015-05-21PCI: pciehp: Drop pointless ACPI-based "slot detection" checkRafael J. Wysocki
Jarod Wilson reports that ExpressCard hotplug doesn't work on HP ZBook G2. The problem turns out to be the ACPI-based "slot detection" code called from pciehp_probe() which uses questionable heuristics based on what ACPI objects are present for the PCIe port device to figure out whether to register a hotplug slot for that port. That code is used if there is at least one PCIe port having an ACPI device configuration object related to hotplug (such as _EJ0 or _RMV), and the Thunderbolt port on the ZBook has _RMV. Of course, Thunderbolt and PCIe native hotplug need not be mutually exclusive (as they aren't on the ZBook), so that rule is simply incorrect. Moreover, the ACPI-based "slot detection" check does not add any value if pciehp_probe() is called at all and the service type of the device object it has been called for is PCIE_PORT_SERVICE_HP, because PCIe hotplug services are only registered if the _OSC handshake in acpi_pci_root_add() allows the kernel to control the PCIe native hotplug feature. No more checks need to be carried out to decide whether or not to register a native PCIe hotlug slot in that case. For the above reasons, make pciehp_probe() check if it has been called for the right service type and drop the pointless ACPI-based "slot detection" check from it. Also remove the entire code whose only user is that check (the entire pciehp_acpi.c file goes away as a result) and drop function headers related to it from the internal pciehp header file. Link: http://lkml.kernel.org/r/1431632038-39917-1-git-send-email-jarod@redhat.com Link: https://bugzilla.kernel.org/show_bug.cgi?id=98581 Reported-by: Jarod Wilson <jarod@redhat.com> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Jarod Wilson <jarod@redhat.com> Tested-by: Jarod Wilson <jarod@redhat.com>
2014-09-12PCI: pciehp: Reduce PCIe slot_ctrl to 16 bitsBjorn Helgaas
4283c70e91dc ("PCI: pciehp: Make pcie_wait_cmd() self-contained") added a cache of the most recent command written to the Slot Control register. This register is only 16 bits wide, but the cache ("slot_ctrl") is 32 bits. Reduce slot_ctrl to a u16 so it matches the register size. No functional change. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-07-05PCI: pciehp: Remove struct controller.no_cmd_completeRajat Jain
"no_cmd_complete" is only used once, and it duplicates read-only information we already have in the cached Slot Capabilities value. Remove the field and use the existing macro NO_CMD_CMPL() instead. [bhelgaas: changelog] Signed-off-by: Rajat Jain <rajatxjain@gmail.com> Signed-off-by: Rajat Jain <rajatjain@juniper.net> Signed-off-by: Guenter Roeck <groeck@juniper.net> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-06-17PCI: pciehp: Compute timeout from hotplug command start timeBjorn Helgaas
If we issue a hotplug command, go do something else, then come back and wait for the command to complete, we don't have to wait the whole timeout period, because some of it elapsed while we were doing something else. Keep track of the time we issued the command, and wait only until the timeout period from that point has elapsed. For controllers with errata like Intel CF118, we previously timed out before issuing the second hotplug command: At time T1 (during boot): - Write DLLSCE, ABPE, PDCE, etc. to Slot Control At time T2 (hotplug event): - Wait for command completion (CC) in Slot Status - Timeout at T2 + 1 second because CC is never set in Slot Status - Write PCC, PIC, etc. to Slot Control With this change, we wait until T1 + 1 second instead of T2 + 1 second. If the hotplug event is more than 1 second after the boot-time initialization, we won't wait for the timeout at all. We still emit a "Timeout on hotplug command" message if it timed out; we should see this on the first hotplug event on every controller with this erratum, as well as on real errors on controllers without the erratum. Link: http://www.intel.com/content/www/us/en/processors/xeon/xeon-e7-v2-spec-update.html Tested-by: Rajat Jain <rajatxjain@gmail.com> (IDT 807a controller) Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2014-06-16PCI: pciehp: Make pcie_wait_cmd() self-containedBjorn Helgaas
pcie_wait_cmd() waits for the controller to finish a hotplug command. Move the associated logic (to determine whether waiting is required and whether we're using interrupts or polling) from pcie_write_cmd() to pcie_wait_cmd(). No functional change. Tested-by: Rajat Jain <rajatxjain@gmail.com> (IDT 807a controller) Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Yinghai Lu <yinghai@kernel.org>
2014-04-14PCI: pciehp: Use PCI_EXP_SLTCAP_PSN defineBjorn Helgaas
Use PCI_EXP_SLTCAP_PSN to make it easier to find code that uses the Physical Slot Number field in the PCIe Slot Capabilities register. No functional change. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-11PCI: pciehp: Add hotplug_lock to serialize hotplug eventsRajat Jain
Today it is there is no protection around pciehp_enable_slot() and pciehp_disable_slot() to ensure that they complete before another hot-plug operation can be done on that particular slot. This patch introduces the slot->hotplug_lock to ensure that any hotplug operations (add / remove) complete before another hotplug event can begin processing on that particular slot. Signed-off-by: Rajat Jain <rajatxjain@gmail.com> Signed-off-by: Rajat Jain <rajatjain@juniper.net> Signed-off-by: Guenter Roeck <groeck@juniper.net> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-10PCI: pciehp: Use link change notifications for hot-plug and removalRajat Jain
A lot of systems do not have the fancy buttons and LEDs, and instead want to rely only on the Link state change events to drive the hotplug and removal state machinery. (http://www.spinics.net/lists/hotplug/msg05802.html) This patch adds support for that functionality. Here are the details about the patch itself: * Define and use interrupt events for linkup / linkdown. * Make the pcie_isr() also look at link events, and direct control to corresponding (new) link state change handler function. * Introduce the functions to handle link-up and link-down events and queue the add / removal work in the slot->wq to be processed by pciehp_power_thread() As a side note, this patch also fixes the bug https://bugzilla.kernel.org/show_bug.cgi?id=65521 "pciehp ignores Data Link Layer State Changed bit." Signed-off-by: Rajat Jain <rajatxjain@gmail.com> Signed-off-by: Rajat Jain <rajatjain@juniper.net> Signed-off-by: Guenter Roeck <groeck@juniper.net> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-02-10PCI: pciehp: Make check_link_active() non-staticRajat Jain
check_link_active() functionality needs to be used by subsequent patches (that introduce link state change based hotplug). Thus make the function non-static, and rename it to pciehp_check_link_active() so as to be consistent with other non-static functions. Signed-off-by: Rajat Jain <rajatxjain@gmail.com> Signed-off-by: Rajat Jain <rajatjain@juniper.net> Signed-off-by: Guenter Roeck <groeck@juniper.net> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-24Merge tag 'pm+acpi-3.14-rc1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: "As far as the number of commits goes, the top spot belongs to ACPI this time with cpufreq in the second position and a handful of PM core, PNP and cpuidle updates. They are fixes and cleanups mostly, as usual, with a couple of new features in the mix. The most visible change is probably that we will create struct acpi_device objects (visible in sysfs) for all devices represented in the ACPI tables regardless of their status and there will be a new sysfs attribute under those objects allowing user space to check that status via _STA. Consequently, ACPI device eject or generally hot-removal will not delete those objects, unless the table containing the corresponding namespace nodes is unloaded, which is extremely rare. Also ACPI container hotplug will be handled quite a bit differently and cpufreq will support CPU boost ("turbo") generically and not only in the acpi-cpufreq driver. Specifics: - ACPI core changes to make it create a struct acpi_device object for every device represented in the ACPI tables during all namespace scans regardless of the current status of that device. In accordance with this, ACPI hotplug operations will not delete those objects, unless the underlying ACPI tables go away. - On top of the above, new sysfs attribute for ACPI device objects allowing user space to check device status by triggering the execution of _STA for its ACPI object. From Srinivas Pandruvada. - ACPI core hotplug changes reducing code duplication, integrating the PCI root hotplug with the core and reworking container hotplug. - ACPI core simplifications making it use ACPI_COMPANION() in the code "glueing" ACPI device objects to "physical" devices. - ACPICA update to upstream version 20131218. This adds support for the DBG2 and PCCT tables to ACPICA, fixes some bugs and improves debug facilities. From Bob Moore, Lv Zheng and Betty Dall. - Init code change to carry out the early ACPI initialization earlier. That should allow us to use ACPI during the timekeeping initialization and possibly to simplify the EFI initialization too. From Chun-Yi Lee. - Clenups of the inclusions of ACPI headers in many places all over from Lv Zheng and Rashika Kheria (work in progress). - New helper for ACPI _DSM execution and rework of the code in drivers that uses _DSM to execute it via the new helper. From Jiang Liu. - New Win8 OSI blacklist entries from Takashi Iwai. - Assorted ACPI fixes and cleanups from Al Stone, Emil Goode, Hanjun Guo, Lan Tianyu, Masanari Iida, Oliver Neukum, Prarit Bhargava, Rashika Kheria, Tang Chen, Zhang Rui. - intel_pstate driver updates, including proper Baytrail support, from Dirk Brandewie and intel_pstate documentation from Ramkumar Ramachandra. - Generic CPU boost ("turbo") support for cpufreq from Lukasz Majewski. - powernow-k6 cpufreq driver fixes from Mikulas Patocka. - cpufreq core fixes and cleanups from Viresh Kumar, Jane Li, Mark Brown. - Assorted cpufreq drivers fixes and cleanups from Anson Huang, John Tobias, Paul Bolle, Paul Walmsley, Sachin Kamat, Shawn Guo, Viresh Kumar. - cpuidle cleanups from Bartlomiej Zolnierkiewicz. - Support for hibernation APM events from Bin Shi. - Hibernation fix to avoid bringing up nonboot CPUs with ACPI EC disabled during thaw transitions from Bjørn Mork. - PM core fixes and cleanups from Ben Dooks, Leonardo Potenza, Ulf Hansson. - PNP subsystem fixes and cleanups from Dmitry Torokhov, Levente Kurusa, Rashika Kheria. - New tool for profiling system suspend from Todd E Brandt and a cpupower tool cleanup from One Thousand Gnomes" * tag 'pm+acpi-3.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (153 commits) thermal: exynos: boost: Automatic enable/disable of BOOST feature (at Exynos4412) cpufreq: exynos4x12: Change L0 driver data to CPUFREQ_BOOST_FREQ Documentation: cpufreq / boost: Update BOOST documentation cpufreq: exynos: Extend Exynos cpufreq driver to support boost cpufreq / boost: Kconfig: Support for software-managed BOOST acpi-cpufreq: Adjust the code to use the common boost attribute cpufreq: Add boost frequency support in core intel_pstate: Add trace point to report internal state. cpufreq: introduce cpufreq_generic_get() routine ARM: SA1100: Create dummy clk_get_rate() to avoid build failures cpufreq: stats: create sysfs entries when cpufreq_stats is a module cpufreq: stats: free table and remove sysfs entry in a single routine cpufreq: stats: remove hotplug notifiers cpufreq: stats: handle cpufreq_unregister_driver() and suspend/resume properly cpufreq: speedstep: remove unused speedstep_get_state platform: introduce OF style 'modalias' support for platform bus PM / tools: new tool for suspend/resume performance optimization ACPI: fix module autoloading for ACPI enumerated devices ACPI: add module autoloading support for ACPI enumerated devices ACPI: fix create_modalias() return value handling ...
2014-01-13Merge branch 'pci/dead-code' into nextBjorn Helgaas
* pci/dead-code: PCI: Make local functions static PCI: Remove unused alloc_pci_dev() PCI: Remove unused pci_renumber_slot() PCI: Remove unused pcie_aspm_enabled() PCI: Remove unused pci_vpd_truncate() PCI: Remove unused ID-Based Ordering support PCI: Remove unused Optimized Buffer Flush/Fill support PCI: Remove unused Latency Tolerance Reporting support PCI: Removed unused parts of Page Request Interface support Conflicts: drivers/pci/pci.c include/linux/pci.h
2014-01-13PCI: Make local functions staticStephen Hemminger
Using 'make namespacecheck' identify code which should be declared static. Checked for users in other driver/archs as well. Compile tested only. This stops exporting the following interfaces to modules: pci_target_state() pci_load_saved_state() [bhelgaas: retained pci_find_next_ext_capability() and pci_cfg_space_size()] Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-12-15PCI: pciehp: Make various functions void since they can't failBjorn Helgaas
These functions: pcie_enable_notification() pciehp_power_off_slot() pciehp_get_power_status() pciehp_get_attention_status() pciehp_set_attention_status() pciehp_get_latch_status() pciehp_get_adapter_status() pcie_write_cmd() now always return success, so this patch makes them void and drops the error-checking code in their callers. No functional change. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-12-07ACPI: Clean up inclusions of ACPI header filesLv Zheng
Replace direct inclusions of <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h>, which are incorrect, with <linux/acpi.h> inclusions and remove some inclusions of those files that aren't necessary. First of all, <acpi/acpi.h>, <acpi/acpi_bus.h> and <acpi/acpi_drivers.h> should not be included directly from any files that are built for CONFIG_ACPI unset, because that generally leads to build warnings about undefined symbols in !CONFIG_ACPI builds. For CONFIG_ACPI set, <linux/acpi.h> includes those files and for CONFIG_ACPI unset it provides stub ACPI symbols to be used in that case. Second, there are ordering dependencies between those files that always have to be met. Namely, it is required that <acpi/acpi_bus.h> be included prior to <acpi/acpi_drivers.h> so that the acpi_pci_root declarations the latter depends on are always there. And <acpi/acpi.h> which provides basic ACPICA type declarations should always be included prior to any other ACPI headers in CONFIG_ACPI builds. That also is taken care of including <linux/acpi.h> as appropriate. Signed-off-by: Lv Zheng <lv.zheng@intel.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Matthew Garrett <mjg59@srcf.ucam.org> Cc: Tony Luck <tony.luck@intel.com> Cc: "H. Peter Anvin" <hpa@zytor.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> (drivers/pci stuff) Acked-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com> (Xen stuff) Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-11-14PCI: Fix whitespace, capitalization, and spelling errorsBjorn Helgaas
Fix whitespace, capitalization, and spelling errors. No functional change. I know "busses" is not an error, but "buses" was more common, so I used it consistently. Signed-off-by: Marta Rybczynska <rybczynska@gmail.com> (pci_reset_bridge_secondary_bus()) Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>