summaryrefslogtreecommitdiffstats
path: root/arch/powerpc/kernel/eeh.c
AgeCommit message (Collapse)AuthorFilesLines
2013-07-24powerpc/eeh: Introdce flag to protect sysfsGavin Shan1-0/+2
The patch introduces flag EEH_DEV_SYSFS to keep track that the sysfs entries for the corresponding EEH device (then PCI device) has been added or removed, in order to avoid race condition. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Use partial hotplug for EEH unaware driversGavin Shan1-3/+27
When EEH error happens to one specific PE, some devices with drivers supporting EEH won't except hotplug on the device. However, there might have other deivces without driver, or with driver without EEH support. For the case, we need do partial hotplug in order to make sure that the PE becomes absolutely quite during reset. Otherise, the PE reset might fail and leads to failure of error recovery. The current code doesn't handle that 'mixed' case properly, it either uses the error callbacks to the drivers, or tries hotplug, but doesn't handle a PE (EEH domain) composed of a combination of the two. The patch intends to support so-called "partial" hotplug for EEH: Before we do reset, we stop and remove those PCI devices without EEH sensitive driver. The corresponding EEH devices are not detached from its PE, but with special flag. After the reset is done, those EEH devices with the special flag will be scanned one by one. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Use safe list traversal when walking EEH devicesGavin Shan1-2/+2
Currently, we're trasversing the EEH devices list using list_for_each_entry(). That's not safe enough because the EEH devices might be removed from its parent PE while doing iteration. The patch replaces that with list_for_each_entry_safe(). Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Keep PE during hotplugGavin Shan1-26/+2
When we do normal hotplug, the PE (shadow EEH structure) shouldn't be kept around. However, we need to keep it if the hotplug an artifial one caused by EEH errors recovery. Since we remove EEH device through the PCI hook pcibios_release_device(), the flag "purge_pe" passed to various functions is meaningless. So the patch removes the meaningless flag and introduce new flag "EEH_PE_KEEP" to save the PE while doing hotplug during EEH error recovery. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Export functions for hotplugGavin Shan1-3/+3
Make some functions public in order to support hotplug on either specific PCI bus or PCI device in future. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-24powerpc/eeh: Remove reference to PCI deviceGavin Shan1-4/+0
We will rely on pcibios_release_device() to remove the EEH cache and unbind EEH device for the specific PCI device. So we shouldn't hold the reference to the PCI device from EEH cache and EEH device. Otherwise, pcibios_release_device() won't be called as we expected. The patch removes the reference to the PCI device in EEH core. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01powerpc/eeh: Avoid build warningsGavin Shan1-1/+1
The patch is for avoiding following build warnings: The function .pnv_pci_ioda_fixup() references the function __init .eeh_init(). This is often because .pnv_pci_ioda_fixup lacks a __init The function .pnv_pci_ioda_fixup() references the function __init .eeh_addr_cache_build(). This is often because .pnv_pci_ioda_fixup lacks a __init Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01powerpc/eeh: Refactor the output messageGavin Shan1-2/+7
We needn't the the whole backtrace other than one-line message in the error reporting interrupt handler. For errors triggered by access PCI config space or MMIO, we replace "WARN(1, ...)" with pr_err() and dump_stack(). The patch also adds more output messages to indicate what EEH core is doing. Besides, some printk() are replaced with pr_warning(). Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-07-01powerpc/eeh: Don't collect PCI-CFG data on PHBGavin Shan1-9/+23
When the PHB is fenced or dead, it's pointless to collect the data from PCI config space of subordinate PCI devices since it should return 0xFF's. The patch also fixes overwritten buffer while getting PCI config data. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-25powerpc/eeh: Remove eeh_mutexGavin Shan1-3/+0
Originally, eeh_mutex was introduced to protect the PE hierarchy tree and the attached EEH devices because EEH core was possiblly running with multiple threads to access the PE hierarchy tree. However, we now have only one kthread in EEH core. So we needn't the eeh_mutex and just remove it. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-21powerpc: Replace find_linux_pte with find_linux_pte_or_hugepteAneesh Kumar K.V1-1/+6
Replace find_linux_pte with find_linux_pte_or_hugepte and explicitly document why we don't need to handle transparent hugepages at callsites. Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Allow to check fenced PHB proactivelyGavin Shan1-0/+60
It's meaningless to handle frozen PE if we already had fenced PHB. The patch intends to check the PHB state before checking PE. If the PHB has been put into fenced state, we need take care of that firstly. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Export confirm_error_lockGavin Shan1-6/+4
An EEH event is created and queued to the event queue for each ingress EEH error. When there're mutiple EEH errors, we need serialize the process to keep consistent PE state (flags). The spinlock "confirm_error_lock" was introduced for the purpose. We'll inject EEH event upon error reporting interrupts on PowerNV platform. So we export the spinlock for that to use for consistent PE state. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Single kthread to handle eventsGavin Shan1-0/+5
We possiblly have multiple kthreads running for multiple EEH errors (events) and use one spinlock to make the process of handling those EEH events serialized. That's unnecessary and the patch creates only one kthread, which is started during EEH core initialization time in eeh_init(). A new semaphore introduced to count the number of existing EEH events in the queue and the kthread waiting on the semaphore. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Delay EEH probe during hotplugGavin Shan1-1/+15
While doing EEH recovery, the PCI devices of the problematic PE should be removed and then added to the system again. During the so-called hotplug event, the PCI devices of the problematic PE will be probed through early/late phase. We would delay EEH probe on late point for PowerNV platform since the PCI device isn't available in early phase. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Refactor eeh_reset_pe_once()Gavin Shan1-1/+2
We shouldn't check that the returned PE status is exactly equal to (EEH_STATE_MMIO_ACTIVE | EEH_STATE_DMA_ACTIVE) but instead only check that they are both set. [benh: changelog] Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: EEH post initialization operationGavin Shan1-0/+11
The patch adds new EEH operation post_init. It's used to notify the platform that EEH core has completed the EEH probe. By that, PowerNV platform starts to use the services supplied by EEH functionality. Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Make eeh_init() publicGavin Shan1-2/+20
For EEH on PowerNV platform, we will do EEH probe based on the real PCI devices. The PCI devices are available after PCI probe. So we have to call eeh_init() explicitly on PowerNV platform after PCI probe. The patch also does EEH probe for PowerNV platform in eeh_init(). Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
2013-06-20powerpc/eeh: Move common part to kernel directoryGavin Shan1-0/+942
The patch moves the common part of EEH core into arch/powerpc/kernel directory so that we needn't PPC_PSERIES while compiling POWERNV platform: * Move the EEH common part into arch/powerpc/kernel * Move the functions for PCI hotplug from pSeries platform to arch/powerpc/kernel/pci-hotplug.c * Move CONFIG_EEH from arch/powerpc/platforms/pseries/Kconfig to arch/powerpc/platforms/Kconfig * Adjust makefile accordingly Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>