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path: root/drivers/pci/pcie/aspm.c
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2019-06-21PCI: let pci_disable_link_state propagate errorsHeiner Kallweit
Drivers may rely on pci_disable_link_state() having disabled certain ASPM link states. If OS can't control ASPM then pci_disable_link_state() turns into a no-op w/o informing the caller. The driver therefore may falsely assume the respective ASPM link states are disabled. Let pci_disable_link_state() propagate errors to the caller, enabling the caller to react accordingly. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-04-06PCI: Rework pcie_retrain_link() wait loopStefan Mätje
Transform wait code to a "do {} while (time_before())" loop as recommended by reviewer. No functional change intended. Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
2019-04-06PCI: Work around Pericom PCIe-to-PCI bridge Retrain Link erratumStefan Mätje
Due to an erratum in some Pericom PCIe-to-PCI bridges in reverse mode (conventional PCI on primary side, PCIe on downstream side), the Retrain Link bit needs to be cleared manually to allow the link training to complete successfully. If it is not cleared manually, the link training is continuously restarted and no devices below the PCI-to-PCIe bridge can be accessed. That means drivers for devices below the bridge will be loaded but won't work and may even crash because the driver is only reading 0xffff. See the Pericom Errata Sheet PI7C9X111SLB_errata_rev1.2_102711.pdf for details. Devices known as affected so far are: PI7C9X110, PI7C9X111SL, PI7C9X130. Add a new flag, clear_retrain_link, in struct pci_dev. Quirks for affected devices set this bit. Note that pcie_retrain_link() lives in aspm.c because that's currently the only place we use it, but this erratum is not specific to ASPM, and we may retrain links for other reasons in the future. Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu> [bhelgaas: apply regardless of CONFIG_PCIEASPM] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> CC: stable@vger.kernel.org
2019-04-06PCI: Factor out pcie_retrain_link() functionStefan Mätje
Factor out pcie_retrain_link() to use for Pericom Retrain Link quirk. No functional change intended. Signed-off-by: Stefan Mätje <stefan.maetje@esd.eu> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> CC: stable@vger.kernel.org
2019-01-05Merge tag 'pci-v4.21-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - Remove unused lists from ASPM pcie_link_state (Frederick Lawler) - Fix Broadcom CNB20LE host bridge unintended sign extension (Colin Ian King) - Expand Kconfig "PF" acronyms (Randy Dunlap) - Update MAINTAINERS for arch/x86/kernel/early-quirks.c (Bjorn Helgaas) - Add missing include to drivers/pci.h (Alexandru Gagniuc) - Override Synopsys USB 3.x HAPS device class so dwc3-haps can claim it instead of xhci (Thinh Nguyen) - Clean up P2PDMA documentation (Randy Dunlap) - Allow runtime PM even if driver doesn't supply callbacks (Jarkko Nikula) - Remove status check after submitting Switchtec MRPC Firmware Download commands to avoid Completion Timeouts (Kelvin Cao) - Set Switchtec coherent DMA mask to allow 64-bit DMA (Boris Glimcher) - Fix Switchtec SWITCHTEC_IOCTL_EVENT_IDX_ALL flag overwrite issue (Joey Zhang) - Enable write combining for Switchtec MRPC Input buffers (Kelvin Cao) - Add Switchtec MRPC DMA mode support (Wesley Sheng) - Skip VF scanning on powerpc, which does this in firmware (Sebastian Ott) - Add Amlogic Meson PCIe controller driver and DT bindings (Yue Wang) - Constify histb dw_pcie_host_ops structure (Julia Lawall) - Support multiple power domains for imx6 (Leonard Crestez) - Constify layerscape driver data (Stefan Agner) - Update imx6 Kconfig to allow imx6 PCIe in imx7 kernel (Trent Piepho) - Support armada8k GPIO reset (Baruch Siach) - Support suspend/resume support on imx6 (Leonard Crestez) - Don't hard-code DesignWare DBI/ATU offst (Stephen Warren) - Skip i.MX6 PHY setup on i.MX7D (Andrey Smirnov) - Remove Jianguo Sun from HiSilicon STB maintainers (Lorenzo Pieralisi) - Mask DesignWare interrupts instead of disabling them to avoid lost interrupts (Marc Zyngier) - Add locking when acking DesignWare interrupts (Marc Zyngier) - Ack DesignWare interrupts in the proper callbacks (Marc Zyngier) - Use devm resource parser in mediatek (Honghui Zhang) - Remove unused mediatek "num-lanes" DT property (Honghui Zhang) - Add UniPhier PCIe controller driver and DT bindings (Kunihiko Hayashi) - Enable MSI for imx6 downstream components (Richard Zhu) * tag 'pci-v4.21-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (40 commits) PCI: imx: Enable MSI from downstream components s390/pci: skip VF scanning PCI/IOV: Add flag so platforms can skip VF scanning PCI/IOV: Factor out sriov_add_vfs() PCI: uniphier: Add UniPhier PCIe host controller support dt-bindings: PCI: Add UniPhier PCIe host controller description PCI: amlogic: Add the Amlogic Meson PCIe controller driver dt-bindings: PCI: meson: add DT bindings for Amlogic Meson PCIe controller arm64: dts: mt7622: Remove un-used property for PCIe arm: dts: mt7623: Remove un-used property for PCIe dt-bindings: PCI: MediaTek: Remove un-used property PCI: mediatek: Remove un-used variant in struct mtk_pcie_port MAINTAINERS: Remove Jianguo Sun from HiSilicon STB DWC entry PCI: dwc: Don't hard-code DBI/ATU offset PCI: imx: Add imx6sx suspend/resume support PCI: armada8k: Add support for gpio controlled reset signal PCI: dwc: Adjust Kconfig to allow IMX6 PCIe host on IMX7 PCI: dwc: layerscape: Constify driver data PCI: imx: Add multi-pd support PCI: Override Synopsys USB 3.x HAPS device class ...
2018-12-17PCI/ASPM: Remove unused lists from struct pcie_link_stateFrederick Lawler
ASPM does not make use of the children or link LIST_HEADs declared in struct pcie_link_state and defined in alloc_pcie_link_state(). Therefore, remove these lists. No functional change intended. Signed-off-by: Frederick Lawler <fred@fredlawl.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-12-03Revert "PCI/ASPM: Do not initialize link state when aspm_disabled is set"Bjorn Helgaas
This reverts commit 17c91487364fb33797ed84022564ee7544ac4945. Rafael found that this commit broke the SD card reader in his Acer Aspire S5. Details of the problem are in the bugzilla below. Fixes: 17c91487364f ("PCI/ASPM: Do not initialize link state when aspm_disabled is set") Link: https://bugzilla.kernel.org/show_bug.cgi?id=201801 Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-18PCI/ASPM: Do not initialize link state when aspm_disabled is setPatrick Talbert
Now that ASPM is configured for *all* PCIe devices at boot, a problem is seen with systems that set the FADT NO_ASPM bit. This bit indicates that the OS should not alter the ASPM state, but when pcie_aspm_init_link_state() runs it only checks for !aspm_support_enabled. This misses the ACPI_FADT_NO_ASPM case because that is setting aspm_disabled. The result is systems may hang at boot after 1302fcf; avoidable if they boot with pcie_aspm=off (sets !aspm_support_enabled). Fix this by having aspm_init_link_state() check for either !aspm_support_enabled or acpm_disabled. Link: https://bugzilla.kernel.org/show_bug.cgi?id=201001 Fixes: 1302fcf0d03e ("PCI: Configure *all* devices, not just hot-added ones") Signed-off-by: Patrick Talbert <ptalbert@redhat.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-09-17PCI/ASPM: Fix link_state teardown on device removalLukas Wunner
Upon removal of the last device on a bus, the link_state of the bridge leading to that bus is sought to be torn down by having pci_stop_dev() call pcie_aspm_exit_link_state(). When ASPM was originally introduced by commit 7d715a6c1ae5 ("PCI: add PCI Express ASPM support"), it determined whether the device being removed is the last one by calling list_empty() on the bridge's subordinate devices list. That didn't work because the device is only removed from the list slightly later in pci_destroy_dev(). Commit 3419c75e15f8 ("PCI: properly clean up ASPM link state on device remove") attempted to fix it by calling list_is_last(), but that's not correct either because it checks whether the device is at the *end* of the list, not whether it's the last one *left* in the list. If the user removes the device which happens to be at the end of the list via sysfs but other devices are preceding the device in the list, the link_state is torn down prematurely. The real fix is to move the invocation of pcie_aspm_exit_link_state() to pci_destroy_dev() and reinstate the call to list_empty(). Remove a duplicate check for dev->bus->self because pcie_aspm_exit_link_state() already contains an identical check. Fixes: 7d715a6c1ae5 ("PCI: add PCI Express ASPM support") Signed-off-by: Lukas Wunner <lukas@wunner.de> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Cc: Shaohua Li <shaohua.li@intel.com> Cc: stable@vger.kernel.org # v2.6.26
2018-08-06PCI/ASPM: Convert to use sysfs_match_string() helperAndy Shevchenko
The sysfs_match_string() helper returns index of the matching string in an array. Use it in pcie_aspm_set_policy() to simplify the code. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> [bhelgaas: squash sysfs_match_string() fix into original patch for issue Reported-by: Heiner Kallweit <hkallweit1@gmail.com>] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-04-18PCI/ASPM: Disable ASPM L1.2 Substate if we don't have LTRBjorn Helgaas
When in the ASPM L1.0 state (but not the PCI-PM L1.0 state), the most recent LTR value and the LTR_L1.2_THRESHOLD determines whether the link enters the L1.2 substate. If we don't have LTR enabled, prevent the use of ASPM L1.2. PCI-PM L1.2 may still be used because it doesn't depend on LTR_L1.2_THRESHOLD (see PCIe r4.0, sec 5.5.1). Tested-by: Srinath Mannam <srinath.mannam@broadcom.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2018-04-04Merge branch 'pci/misc'Bjorn Helgaas
- use PCI_EXP_DEVCTL2_COMP_TIMEOUT in rapidio/tsi721 (Bjorn Helgaas) - remove possible NULL pointer dereference in of_pci_bus_find_domain_nr() (Shawn Lin) - report quirk timings with dev_info (Bjorn Helgaas) - report quirks that take longer than 10ms (Bjorn Helgaas) - add and use Altera Vendor ID (Johannes Thumshirn) - tidy Makefiles and comments (Bjorn Helgaas) * pci/misc: PCI: Always define the of_node helpers PCI: Tidy comments PCI: Tidy Makefiles mcb: Add Altera PCI ID to mcb-pci PCI: Add Altera vendor ID PCI: Report quirks that take more than 10ms PCI: Report quirk timings with pci_info() instead of pr_debug() PCI: Fix NULL pointer dereference in of_pci_bus_find_domain_nr() rapidio/tsi721: use PCI_EXP_DEVCTL2_COMP_TIMEOUT macro
2018-03-19PCI: Tidy commentsBjorn Helgaas
Remove pointless comments that tell us the file name, remove blank line comments, follow multi-line comment conventions. No functional change intended. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2018-02-28PCI/ASPM: Don't warn if already in common clock modeSinan Kaya
Previously we emitted a warning if we tried to configure common clock mode the link was already configured to common clock mode by the UEFI BIOS. Bail out silently in that case instead of emitting the warning: pci 0004:00:00.0: ASPM: Could not configure common clock Signed-off-by: Sinan Kaya <okaya@codeaurora.org> [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>
2018-02-28PCI/ASPM: Declare threshold_ns as u32, not u64Gustavo A. R. Silva
aspm_calc_l1ss_info() computes l1_2_threshold in microseconds as: l1_2_threshold = 2 + 4 + t_common_mode + t_power_on; where t_common_mode is at most 255us: PCI_L1SS_CAP_CM_RESTORE_TIME 0x0000ff00 <-- 8 bits; <256us and t_power_on is at most 31 * 100us = 3100us: PCI_L1SS_CAP_P_PWR_ON_VALUE 0x00f80000 <-- 5 bits; <32 PCI_L1SS_CAP_P_PWR_ON_SCALE 0x00030000 <-- *2us, *10us, or *100us So l1_2_threshold is at most 2 + 4 + 255 + 3100 = 3361, which means threshold_ns is at most 3361 * 1000 = 3361000, which easily fits in a u32. Declare threshold_ns as u32, not u64. This fixes a Coverity warning. Addresses-Coverity-ID: 1462501 Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com> [bhelgaas: changelog] Signed-off-by: Bjorn Helgaas <helgaas@kernel.org> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
2018-01-31Merge branch 'pci/misc' into nextBjorn Helgaas
* pci/misc: PCI: Add dummy pci_irqd_intx_xlate() for CONFIG_PCI=n build PCI: Add wrappers for dev_printk() PCI: Remove unnecessary messages for memory allocation failures PCI: Add #defines for Completion Timeout Disable feature hinic: Replace PCI pool old API net: e100: Replace PCI pool old API block: DAC960: Replace PCI pool old API MAINTAINERS: Include more PCI files PCI: Remove unneeded kallsyms include powerpc/pci: Unroll two pass loop when scanning bridges powerpc/pci: Use for_each_pci_bridge() helper
2018-01-18PCI: Add wrappers for dev_printk()Frederick Lawler
Add PCI-specific dev_printk() wrappers and use them to simplify the code slightly. No functional change intended. Signed-off-by: Frederick Lawler <fred@fredlawl.com> [bhelgaas: squash into one patch] Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-12-18PCI/ASPM: Calculate LTR_L1.2_THRESHOLD from device characteristicsBjorn Helgaas
Per PCIe r3.1, sec 5.5.1, LTR_L1.2_THRESHOLD determines whether we enter the L1.2 Link state: if L1.2 is enabled and downstream devices have reported that they can tolerate latency of at least LTR_L1.2_THRESHOLD, we must enter L1.2 when CLKREQ# is de-asserted. The implication is that LTR_L1.2_THRESHOLD is the time required to transition the Link from L0 to L1.2 and back to L0, and per sec 5.5.3.3.1, Figures 5-16 and 5-17, it appears that the absolute minimum time for those transitions would be T(POWER_OFF) + T(L1.2) + T(POWER_ON) + T(COMMONMODE). Therefore, compute LTR_L1.2_THRESHOLD as: 2us T(POWER_OFF) + 4us T(L1.2) + T(POWER_ON) + T(COMMONMODE) = LTR_L1.2_THRESHOLD Previously we set LTR_L1.2_THRESHOLD to a fixed value of 163840ns (163.84us): #define LTR_L1_2_THRESHOLD_BITS ((1 << 21) | (1 << 23) | (1 << 30)) ((1 << 21) | (1 << 23) | (1 << 30)) = 0x40a00000 LTR_L1.2_THRESHOLD_Value = (0x40a00000 & 0x03ff0000) >> 16 = 0xa0 = 160 LTR_L1.2_THRESHOLD_Scale = (0x40a00000 & 0xe0000000) >> 29 = 0x2 (* 1024ns) LTR_L1.2_THRESHOLD = 160 * 1024ns = 163840ns Obviously this doesn't account for the circuit characteristics of different implementations. Note that while firmware may enable LTR, Linux itself currently does not enable LTR. When L1.2 is enabled but LTR is not, LTR_L1.2_THRESHOLD is ignored and we always enter L1.2 when it is enabled and CLKREQ# is de-asserted. So this patch should not have any effect unless firmware enables LTR. Fixes: f1f0366dd6be ("PCI/ASPM: Calculate and save the L1.2 timing parameters") Link: https://www.coreboot.org/pipermail/coreboot-gerrit/2015-March/021134.html Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Vidya Sagar <vidyas@nvidia.com> Cc: Kenji Chen <kenji.chen@intel.com> Cc: Patrick Georgi <pgeorgi@google.com> Cc: Rajat Jain <rajatja@google.com>
2017-11-15Merge tag 'pci-v4.15-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - detach driver before tearing down procfs/sysfs (Alex Williamson) - disable PCIe services during shutdown (Sinan Kaya) - fix ASPM oops on systems with no Root Ports (Ard Biesheuvel) - fix ASPM LTR_L1.2_THRESHOLD programming (Bjorn Helgaas) - fix ASPM Common_Mode_Restore_Time computation (Bjorn Helgaas) - fix portdrv MSI/MSI-X vector allocation (Dongdong Liu, Bjorn Helgaas) - report non-fatal AER errors only to the affected endpoint (Gabriele Paoloni) - distribute bus numbers, MMIO, and I/O space among hotplug bridges to allow more devices to be hot-added (Mika Westerberg) - fix pciehp races during initialization and surprise link down (Mika Westerberg) - handle surprise-removed devices in PME handling (Qiang) - support resizable BARs for large graphics devices (Christian König) - expose SR-IOV offset, stride, and VF device ID via sysfs (Filippo Sironi) - create SR-IOV virtfn/physfn sysfs links before attaching driver (Stuart Hayes) - fix SR-IOV "ARI Capable Hierarchy" restore issue (Tony Nguyen) - enforce Kconfig IOV/REALLOC dependency (Sascha El-Sharkawy) - avoid slot reset if bridge itself is broken (Jan Glauber) - clean up pci_reset_function() path (Jan H. Schönherr) - make pci_map_rom() fail if the option ROM is invalid (Changbin Du) - convert timers to timer_setup() (Kees Cook) - move PCI_QUIRKS to PCI bus Kconfig menu (Randy Dunlap) - constify pci_dev_type and intel_mid_pci_ops (Bhumika Goyal) - remove unnecessary pci_dev, pci_bus, resource, pcibios_set_master() declarations (Bjorn Helgaas) - fix endpoint framework overflows and BUG()s (Dan Carpenter) - fix endpoint framework issues (Kishon Vijay Abraham I) - avoid broken Cavium CN8xxx bus reset behavior (David Daney) - extend Cavium ACS capability quirks (Vadim Lomovtsev) - support Synopsys DesignWare RC in ECAM mode (Ard Biesheuvel) - turn off dra7xx clocks cleanly on shutdown (Keerthy) - fix Faraday probe error path (Wei Yongjun) - support HiSilicon STB SoC PCIe host controller (Jianguo Sun) - fix Hyper-V interrupt affinity issue (Dexuan Cui) - remove useless ACPI warning for Hyper-V pass-through devices (Vitaly Kuznetsov) - support multiple MSI on iProc (Sandor Bodo-Merle) - support Layerscape LS1012a and LS1046a PCIe host controllers (Hou Zhiqiang) - fix Layerscape default error response (Minghuan Lian) - support MSI on Tango host controller (Marc Gonzalez) - support Tegra186 PCIe host controller (Manikanta Maddireddy) - use generic accessors on Tegra when possible (Thierry Reding) - support V3 Semiconductor PCI host controller (Linus Walleij) * tag 'pci-v4.15-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (85 commits) PCI/ASPM: Add L1 Substates definitions PCI/ASPM: Reformat ASPM register definitions PCI/ASPM: Use correct capability pointer to program LTR_L1.2_THRESHOLD PCI/ASPM: Account for downstream device's Port Common_Mode_Restore_Time PCI: xgene: Rename xgene_pcie_probe_bridge() to xgene_pcie_probe() PCI: xilinx: Rename xilinx_pcie_link_is_up() to xilinx_pcie_link_up() PCI: altera: Rename altera_pcie_link_is_up() to altera_pcie_link_up() PCI: Fix kernel-doc build warning PCI: Fail pci_map_rom() if the option ROM is invalid PCI: Move pci_map_rom() error path PCI: Move PCI_QUIRKS to the PCI bus menu alpha/PCI: Make pdev_save_srm_config() static PCI: Remove unused declarations PCI: Remove redundant pci_dev, pci_bus, resource declarations PCI: Remove redundant pcibios_set_master() declarations PCI/PME: Handle invalid data when reading Root Status PCI: hv: Use effective affinity mask PCI: pciehp: Do not clear Presence Detect Changed during initialization PCI: pciehp: Fix race condition handling surprise link down PCI: Distribute available resources to hotplug-capable bridges ...
2017-11-15Merge tag 'modules-for-v4.15' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux Pull module updates from Jessica Yu: "Summary of modules changes for the 4.15 merge window: - treewide module_param_call() cleanup, fix up set/get function prototype mismatches, from Kees Cook - minor code cleanups" * tag 'modules-for-v4.15' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux: module: Do not paper over type mismatches in module_param_call() treewide: Fix function prototypes for module_param_call() module: Prepare to convert all module_param_call() prototypes kernel/module: Delete an error message for a failed memory allocation in add_module_usage()
2017-11-14PCI/ASPM: Add L1 Substates definitionsBjorn Helgaas
Add and use #defines for L1 Substate register fields instead of hard-coding the masks. Also update comments to use names from the spec. No functional change intended. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Vidya Sagar <vidyas@nvidia.com>
2017-11-14PCI/ASPM: Use correct capability pointer to program LTR_L1.2_THRESHOLDBjorn Helgaas
Previously we programmed the LTR_L1.2_THRESHOLD in the parent (upstream) device using the capability pointer of the *child* (downstream) device, which corrupted some random word of the parent's config space. Use the parent's L1 SS capability pointer to program its LTR_L1.2_THRESHOLD. Fixes: aeda9adebab8 ("PCI/ASPM: Configure L1 substate settings") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Vidya Sagar <vidyas@nvidia.com> CC: stable@vger.kernel.org # v4.11+ CC: Rajat Jain <rajatja@google.com>
2017-11-13PCI/ASPM: Account for downstream device's Port Common_Mode_Restore_TimeBjorn Helgaas
Every Port that supports the L1.2 substate advertises its Port Common_Mode_Restore_Time, i.e., the time the Port requires to re-establish common mode when exiting L1.2 (see PCIe r3.1, sec 7.33.2). Per sec 5.5.3.3.1, when exiting L1.2, the Downstream Port (the device at the upstream end of the link) must send TS1 training sequences for at least T(COMMONMODE) after it detects electrical idle exit on the Link. We want this to be long enough for both ends of the Link, so we should set it to the maximum of the Port Common_Mode_Restore_Time for the upstream and downstream components on the Link. Previously we only looked at the Port Common_Mode_Restore_Time of the upstream device, so if the downstream device required more time, we didn't program the upstream device's T(COMMONMODE) correctly. Fixes: f1f0366dd6be ("PCI/ASPM: Calculate and save the L1.2 timing parameters") Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: Vidya Sagar <vidyas@nvidia.com> Acked-by: Rajat Jain <rajatja@google.com> CC: stable@vger.kernel.org # v4.11+
2017-11-02License cleanup: add SPDX GPL-2.0 license identifier to files with no licenseGreg Kroah-Hartman
Many source files in the tree are missing licensing information, which makes it harder for compliance tools to determine the correct license. By default all files without license information are under the default license of the kernel, which is GPL version 2. Update the files which contain no license information with the 'GPL-2.0' SPDX license identifier. The SPDX identifier is a legally binding shorthand, which can be used instead of the full boiler plate text. This patch is based on work done by Thomas Gleixner and Kate Stewart and Philippe Ombredanne. How this work was done: Patches were generated and checked against linux-4.14-rc6 for a subset of the use cases: - file had no licensing information it it. - file was a */uapi/* one with no licensing information in it, - file was a */uapi/* one with existing licensing information, Further patches will be generated in subsequent months to fix up cases where non-standard license headers were used, and references to license had to be inferred by heuristics based on keywords. The analysis to determine which SPDX License Identifier to be applied to a file was done in a spreadsheet of side by side results from of the output of two independent scanners (ScanCode & Windriver) producing SPDX tag:value files created by Philippe Ombredanne. Philippe prepared the base worksheet, and did an initial spot review of a few 1000 files. The 4.13 kernel was the starting point of the analysis with 60,537 files assessed. Kate Stewart did a file by file comparison of the scanner results in the spreadsheet to determine which SPDX license identifier(s) to be applied to the file. She confirmed any determination that was not immediately clear with lawyers working with the Linux Foundation. Criteria used to select files for SPDX license identifier tagging was: - Files considered eligible had to be source code files. - Make and config files were included as candidates if they contained >5 lines of source - File already had some variant of a license header in it (even if <5 lines). All documentation files were explicitly excluded. The following heuristics were used to determine which SPDX license identifiers to apply. - when both scanners couldn't find any license traces, file was considered to have no license information in it, and the top level COPYING file license applied. For non */uapi/* files that summary was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 11139 and resulted in the first patch in this series. If that file was a */uapi/* path one, it was "GPL-2.0 WITH Linux-syscall-note" otherwise it was "GPL-2.0". Results of that was: SPDX license identifier # files ---------------------------------------------------|------- GPL-2.0 WITH Linux-syscall-note 930 and resulted in the second patch in this series. - if a file had some form of licensing information in it, and was one of the */uapi/* ones, it was denoted with the Linux-syscall-note if any GPL family license was found in the file or had no licensing in it (per prior point). Results summary: SPDX license identifier # files ---------------------------------------------------|------ GPL-2.0 WITH Linux-syscall-note 270 GPL-2.0+ WITH Linux-syscall-note 169 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-2-Clause) 21 ((GPL-2.0 WITH Linux-syscall-note) OR BSD-3-Clause) 17 LGPL-2.1+ WITH Linux-syscall-note 15 GPL-1.0+ WITH Linux-syscall-note 14 ((GPL-2.0+ WITH Linux-syscall-note) OR BSD-3-Clause) 5 LGPL-2.0+ WITH Linux-syscall-note 4 LGPL-2.1 WITH Linux-syscall-note 3 ((GPL-2.0 WITH Linux-syscall-note) OR MIT) 3 ((GPL-2.0 WITH Linux-syscall-note) AND MIT) 1 and that resulted in the third patch in this series. - when the two scanners agreed on the detected license(s), that became the concluded license(s). - when there was disagreement between the two scanners (one detected a license but the other didn't, or they both detected different licenses) a manual inspection of the file occurred. - In most cases a manual inspection of the information in the file resulted in a clear resolution of the license that should apply (and which scanner probably needed to revisit its heuristics). - When it was not immediately clear, the license identifier was confirmed with lawyers working with the Linux Foundation. - If there was any question as to the appropriate license identifier, the file was flagged for further research and to be revisited later in time. In total, over 70 hours of logged manual review was done on the spreadsheet to determine the SPDX license identifiers to apply to the source files by Kate, Philippe, Thomas and, in some cases, confirmation by lawyers working with the Linux Foundation. Kate also obtained a third independent scan of the 4.13 code base from FOSSology, and compared selected files where the other two scanners disagreed against that SPDX file, to see if there was new insights. The Windriver scanner is based on an older version of FOSSology in part, so they are related. Thomas did random spot checks in about 500 files from the spreadsheets for the uapi headers and agreed with SPDX license identifier in the files he inspected. For the non-uapi files Thomas did random spot checks in about 15000 files. In initial set of patches against 4.14-rc6, 3 files were found to have copy/paste license identifier errors, and have been fixed to reflect the correct identifier. Additionally Philippe spent 10 hours this week doing a detailed manual inspection and review of the 12,461 patched files from the initial patch version early this week with: - a full scancode scan run, collecting the matched texts, detected license ids and scores - reviewing anything where there was a license detected (about 500+ files) to ensure that the applied SPDX license was correct - reviewing anything where there was no detection but the patch license was not GPL-2.0 WITH Linux-syscall-note to ensure that the applied SPDX license was correct This produced a worksheet with 20 files needing minor correction. This worksheet was then exported into 3 different .csv files for the different types of files to be modified. These .csv files were then reviewed by Greg. Thomas wrote a script to parse the csv files and add the proper SPDX tag to the file, in the format that the file expected. This script was further refined by Greg based on the output to detect more types of files automatically and to distinguish between header and source .c files (which need different comment types.) Finally Greg ran the script using the .csv files to generate the patches. Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Reviewed-by: Philippe Ombredanne <pombredanne@nexb.com> Reviewed-by: Thomas Gleixner <tglx@linutronix.de> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2017-10-31treewide: Fix function prototypes for module_param_call()Kees Cook
Several function prototypes for the set/get functions defined by module_param_call() have a slightly wrong argument types. This fixes those in an effort to clean up the calls when running under type-enforced compiler instrumentation for CFI. This is the result of running the following semantic patch: @match_module_param_call_function@ declarer name module_param_call; identifier _name, _set_func, _get_func; expression _arg, _mode; @@ module_param_call(_name, _set_func, _get_func, _arg, _mode); @fix_set_prototype depends on match_module_param_call_function@ identifier match_module_param_call_function._set_func; identifier _val, _param; type _val_type, _param_type; @@ int _set_func( -_val_type _val +const char * _val , -_param_type _param +const struct kernel_param * _param ) { ... } @fix_get_prototype depends on match_module_param_call_function@ identifier match_module_param_call_function._get_func; identifier _val, _param; type _val_type, _param_type; @@ int _get_func( -_val_type _val +char * _val , -_param_type _param +const struct kernel_param * _param ) { ... } Two additional by-hand changes are included for places where the above Coccinelle script didn't notice them: drivers/platform/x86/thinkpad_acpi.c fs/lockd/svc.c Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: Jessica Yu <jeyu@kernel.org>
2017-10-05PCI/ASPM: Deal with missing root ports in link state handlingArd Biesheuvel
Even though it is unconventional, some PCIe host implementations omit the root ports entirely, and simply consist of a host bridge (which is not modeled as a device in the PCI hierarchy) and a link. When the downstream device is an endpoint, our current code does not seem to mind this unusual configuration. However, when PCIe switches are involved, the ASPM code assumes that any downstream switch port has a parent, and blindly dereferences the bus->parent->self field of the pci_dev struct to chain the downstream link state to the link state of the root port. Given that the root port is missing, the link is not modeled at all, and nor is the link state, and attempting to access it results in a NULL pointer dereference and a crash. Avoid this by allowing the link state chain to terminate at the downstream port if no root port exists. Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-03-07PCI/ASPM: Always set link->downstream to avoid NULL dereference on removeYinghai Lu
We call pcie_aspm_exit_link_state() when we remove a device. If the device is the last PCIe function to be removed below a bridge and the bridge has an ASPM link_state struct, we disable ASPM on the link. Disabling ASPM requires link->downstream (used in pcie_config_aspm_link()). We previously set link->downstream in pcie_aspm_cap_init(), but only if the device was not blacklisted. Removing the blacklisted device caused a NULL pointer dereference in the pcie_aspm_exit_link_state() -> pcie_config_aspm_link() path: # echo 1 > /sys/bus/pci/devices/0000\:0b\:00.0/remove ... BUG: unable to handle kernel NULL pointer dereference at 0000000000000080 IP: pcie_config_aspm_link+0x5d/0x2b0 Call Trace: pcie_aspm_exit_link_state+0x75/0x130 pci_stop_bus_device+0xa4/0xb0 pci_stop_and_remove_bus_device_locked+0x1a/0x30 remove_store+0x50/0x70 dev_attr_store+0x18/0x30 sysfs_kf_write+0x44/0x60 kernfs_fop_write+0x10e/0x190 __vfs_write+0x28/0x110 ? rcu_read_lock_sched_held+0x5d/0x80 ? rcu_sync_lockdep_assert+0x2c/0x60 ? __sb_start_write+0x173/0x1a0 ? vfs_write+0xb3/0x180 vfs_write+0xc4/0x180 SyS_write+0x49/0xa0 do_syscall_64+0xa6/0x1c0 entry_SYSCALL64_slow_path+0x25/0x25 ---[ end trace bd187ee0267df5d9 ]--- To avoid this, set link->downstream in alloc_pcie_link_state(), so every pcie_link_state structure has a valid link->downstream pointer. [bhelgaas: changelog] Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Rajat Jain <rajatja@google.com> CC: stable@vger.kernel.org
2017-02-23Merge tag 'pci-v4.11-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI updates from Bjorn Helgaas: - add ASPM L1 substate support - enable PCIe Extended Tags when supported - configure PCIe MPS settings on iProc, Versatile, X-Gene, and Xilinx - increase VPD access timeout - add ACS quirks for Intel Union Point, Qualcomm QDF2400 and QDF2432 - use new pci_irq_alloc_vectors() in more drivers - fix MSI affinity memory leak - remove unused MSI interfaces and update documentation - remove unused AER .link_reset() callback - avoid pci_lock / p->pi_lock deadlock seen with perf - serialize sysfs enable/disable num_vfs operations - move DesignWare IP from drivers/pci/host/ to drivers/pci/dwc/ and refactor so we can support both hosts and endpoints - add DT ECAM-like support for HiSilicon Hip06/Hip07 controllers - add Rockchip system power management support - add Thunder-X cn81xx and cn83xx support - add Exynos 5440 PCIe PHY support * tag 'pci-v4.11-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (93 commits) PCI: dwc: Remove dependency of designware on CONFIG_PCI PCI: dwc: Add CONFIG_PCIE_DW_HOST to enable PCI dwc host PCI: dwc: Split pcie-designware.c into host and core files PCI: dwc: designware: Fix style errors in pcie-designware.c PCI: dwc: designware: Parse "num-lanes" property in dw_pcie_setup_rc() PCI: dwc: all: Split struct pcie_port into host-only and core structures PCI: dwc: designware: Get device pointer at the start of dw_pcie_host_init() PCI: dwc: all: Rename cfg_read/cfg_write to read/write PCI: dwc: all: Use platform_set_drvdata() to save private data PCI: dwc: designware: Move register defines to designware header file PCI: dwc: Use PTR_ERR_OR_ZERO to simplify code PCI: dra7xx: Group PHY API invocations PCI: dra7xx: Enable MSI and legacy interrupts simultaneously PCI: dra7xx: Add support to force RC to work in GEN1 mode PCI: dra7xx: Simplify probe code with devm_gpiod_get_optional() PCI: Move DesignWare IP support to new drivers/pci/dwc/ directory PCI: exynos: Support the PHY generic framework Documentation: binding: Modify the exynos5440 PCIe binding phy: phy-exynos-pcie: Add support for Exynos PCIe PHY Documentation: samsung-phy: Add exynos-pcie-phy binding ...
2017-02-14PCI/ASPM: Add comment about L1 substate latencyRajat Jain
Since the exit latencies for L1 substates are not advertised by a device, it is not clear in spec how to do a L1 substate exit latency check. We assume that the L1 exit latencies advertised by a device include L1 substate latencies (and hence do not do any check). If that is not true, we should do some sort of check here. (I'm not clear about what that check should like currently. I'd be glad to take up any suggestions). Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-02-14PCI/ASPM: Configure L1 substate settingsRajat Jain
Configure the L1 substate settings on the upstream and downstream devices, while taking care of the rules dictated by the PCIe spec. [bhelgaas: drop "inline"] Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-02-14PCI/ASPM: Calculate and save the L1.2 timing parametersRajat Jain
Calculate and save the timing parameters that need to be programmed if we need to enable L1.2 substates later. We use the same logic (and a constant value for 1 of the parameters) as used by Intel's coreboot: https://www.coreboot.org/pipermail/coreboot-gerrit/2015-March/021134.html https://review.coreboot.org/#/c/8832/ Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-02-14PCI/ASPM: Read and set up L1 substate capabilitiesRajat Jain
The PCIe spec (r3.1, sec 7.33) says the L1 PM Substates Capability may be implemented only in function 0. Read the L1 substate capability structures of upstream and downstream components of the link and set it up in the device structure. [bhelgaas: add specific spec reference] Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-02-14PCI/ASPM: Add support for L1 substatesRajat Jain
Add support for ASPM L1 substates. For details about L1 substates, see the PCIe r3.1 spec, which includes the ECN below in secs 5.5 and 7.33. Add macros for the 4 new L1 substates, and add a new ASPM "POWER_SUPERSAVE" policy that can be used to enable L1 substates on a system if desired. The new policy is in a sense, a superset of the existing POWERSAVE policy. The 4 policies are now: DEFAULT: Reads and uses whatever ASPM states BIOS enabled PERFORMANCE: Everything except L0 disabled. POWERSAVE: L0s and L1 enabled (but not L1 substates) POWER_SUPERSAVE: L0s + L1 + L1 substates also enabled [bhelgaas: add PCIe r3.1 spec reference] Link: https://pcisig.com/sites/default/files/specification_documents/ECN_L1_PM_Substates_with_CLKREQ_31_May_2013_Rev10a.pdf Signed-off-by: Rajat Jain <rajatja@google.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2017-01-27PCI/ASPM: Handle PCI-to-PCIe bridges as roots of PCIe hierarchiesBjorn Helgaas
In a struct pcie_link_state, link->root points to the pcie_link_state of the root of the PCIe hierarchy. For the topmost link, this points to itself (link->root = link). For others, we copy the pointer from the parent (link->root = link->parent->root). Previously we recognized that Root Ports originated PCIe hierarchies, but we treated PCI/PCI-X to PCIe Bridges as being in the middle of the hierarchy, and when we tried to copy the pointer from link->parent->root, there was no parent, and we dereferenced a NULL pointer: BUG: unable to handle kernel NULL pointer dereference at 0000000000000090 IP: [<ffffffff9e424350>] pcie_aspm_init_link_state+0x170/0x820 Recognize that PCI/PCI-X to PCIe Bridges originate PCIe hierarchies just like Root Ports do, so link->root for these devices should also point to itself. Fixes: 51ebfc92b72b ("PCI: Enumerate switches below PCI-to-PCIe bridges") Link: https://bugzilla.kernel.org/show_bug.cgi?id=193411 Link: https://bugzilla.opensuse.org/show_bug.cgi?id=1022181 Tested-by: lists@ssl-mail.com Tested-by: Jayachandran C. <jnair@caviumnetworks.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: stable@vger.kernel.org # v4.2+
2016-12-08PCI/ASPM: Don't retrain link if ASPM not possibleDavid Daney
Some (defective) PCIe devices are not able to reliably do link retraining. Check to see if ASPM is possible between link partners before configuring common clocking, and doing the resulting link retraining. If ASPM is not possible, there is no reason to risk losing access to a device due to an unnecessary link retraining. Signed-off-by: David Daney <david.daney@cavium.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-11-14PCI/ASPM: Use permission-specific DEVICE_ATTR variantsJulia Lawall
Use DEVICE_ATTR_RW for read-write attributes. This simplifies the source code, improves readability, and reduces the chance of inconsistencies. The semantic patch that makes this change is as follows: (http://coccinelle.lip6.fr/) // <smpl> @rw@ declarer name DEVICE_ATTR; identifier x,x_show,x_store; @@ DEVICE_ATTR(x, \(0644\|S_IRUGO|S_IWUSR\), x_show, x_store); @script:ocaml@ x << rw.x; x_show << rw.x_show; x_store << rw.x_store; @@ if not (x^"_show" = x_show && x^"_store" = x_store) then Coccilib.include_match false @@ declarer name DEVICE_ATTR_RW; identifier rw.x,rw.x_show,rw.x_store; @@ - DEVICE_ATTR(x, \(0644\|S_IRUGO|S_IWUSR\), x_show, x_store); + DEVICE_ATTR_RW(x); // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2016-06-10PCI/ASPM: Remove redundant check of pcie_set_clkpmShawn Lin
Without supporting clock PM capable, if we want to disable clkpm, we don't need this extra check as it must already be zero for the enable argument. And it's the same for enabling clkpm here. So let's remove this check. Signed-off-by: Shawn Lin <shawn.lin@rock-chips.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-12-03PCI/ASPM: Make sysfs link_state_store() consistent with link_state_show()Andy Lutomirski
If CONFIG_PCIEASPM_DEBUG is set, then PCI devices have a link_state attribute. Reading that attribute shows the state as a bit mask: 1 means L0S upstream, 2 means L0S downstream, and 4 means L1. Oddly, writing to link_state is inconsistent and gets translated, leading to mysterious results in which the value you store isn't comparable the value you load back out. Fix it by making link_state_store() match link_state_show(). [bhelgaas: Check "aspm_disabled" *before* validating input. When "aspm_disabled" is set, this changes the error for invalid input from -EINVAL to -EPERM.] Signed-off-by: Andy Lutomirski <luto@kernel.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-06-10PCI/ASPM: Simplify Clock Power Management settingBjorn Helgaas
Update the Link Control Enable Clock Power Management bit the same way we update the ASPM Control bits, with a single call of pcie_capability_clear_and_set_word(). No functional change; this just makes both paths use the same style. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-26PCI/ASPM: Use dev->has_secondary_link to find downstream linksYijing Wang
We allocate pcie_link_state for the component at the upstream end of a Link. Previously we did this by allocating pcie_link_state for Root Ports and Downstream Ports. This works fine for the typical topology: 00:1c.0 Root Port [bridge to bus 02] 02:00.0 Upstream Port [bridge to bus 03] 03:00.0 Downstream Port [bridge to bus 04] 04:00.0 Endpoint or Switch Port However, it is possible to have a Root Port connected to a Downstream Port instead of an Upstream Port, as in Robert White's ATCA system: 00:1c.0 Root Port [bridge to bus 02] 02:00.0 Downstream Port [bridge to bus 03] 03:01.0 Downstream Port [bridge to bus 04] 04:00.0 Endpoint or Switch Port In this topology, we wrongly allocated pcie_link_state for the 02:00.0 Downstream Port, which is actually the *downstream* end of a link. This led to the following NULL pointer dereference when we tried to connect this link into the tree of links starting at the 00:1c.0 Root Port: BUG: unable to handle kernel NULL pointer dereference at 0000000000000088 IP: [<ffffffff81550324>] pcie_aspm_init_link_state+0x744/0x850 Hardware name: Kontron B3001/B3001, BIOS 4.6.3 08/07/2012 Call Trace: [<ffffffff8153b865>] pci_scan_slot+0xd5/0x120 [<ffffffff8153ca1d>] pci_scan_child_bus+0x2d/0xd0 ... Instead of relying on the component type to identify the upstream end of a link, use the "dev->has_secondary_link" field. This means it's now possible for an Upstream Port to have a link on its secondary side, so alloc_pcie_link_state() needs to connect links originating from both Upstream and Downstream Ports into the tree. [bhelgaas: changelog, add comment] Link: https://bugzilla.kernel.org/show_bug.cgi?id=94361 Link: http://lkml.kernel.org/r/54EB81B2.4050904@pobox.com Reported-by: Robert White <rwhite@pobox.com> Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-20PCI/ASPM: Remove redundant PCIe port type checkingYijing Wang
We decide in alloc_pcie_link_state() whether to allocate a pcie_link_state for a device. After that, it's sufficient to check pdev->link_state. We don't need to check the PCIe port type again. Remove the redundant PCIe port type checking. [bhelgaas: changelog] Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-05-20PCI/ASPM: Drop __pci_disable_link_state() useless "force" parameterBjorn Helgaas
After 387d37577fdd ("PCI: Don't clear ASPM bits when the FADT declares it's unsupported"), the "force" parameter to __pci_disable_link_state() is always "false". Remove the "force" parameter and assume it's always false. Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-04-09PCI: Don't clear ASPM bits when the FADT declares it's unsupportedMatthew Garrett
Communications with a hardware vendor confirm that the expected behaviour on systems that set the FADT ASPM disable bit but which still grant full PCIe control is for the OS to leave any BIOS configuration intact and refuse to touch the ASPM bits. This mimics the behaviour of Windows. Signed-off-by: Matthew Garrett <mjg59@coreos.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2015-01-09PCI/ASPM: Use standard parsing functions for sysfs settersChris J Arges
The functions link_state_store() and clk_ctl_store() had just subtracted ASCII '0' from input which could lead to undesired results. Instead, use Linux string functions to safely parse input. [bhelgaas: check kstrtouint() return value] Signed-off-by: Chris J Arges <chris.j.arges@canonical.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2014-01-13PCI: Remove unused pcie_aspm_enabled()Stephen Hemminger
My philosophy is unused code is dead code. And dead code is subject to bit rot and is a likely source of bugs. Use it or lose it. This reverts part of 3e1b16002af2 ("ACPI/PCI: PCIe ASPM _OSC support capabilities called when root bridge added"), removing this interface: pcie_aspm_enabled() [bhelgaas: split to separate patch] Signed-off-by: Stephen Hemminger <stephen@networkplumber.org> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> CC: Andrew Patterson <andrew.patterson@hp.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>
2013-05-28PCI: Fix kerneldoc for pci_disable_link_state()Yijing Wang
Fix kerneldoc for pci_disable_link_state(). [bhelgaas: expand comment, fix typos] Signed-off-by: Yijing Wang <wangyijing@huawei.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-05-21PCI/ASPM: Warn when driver asks to disable ASPM, but we can't do itBjorn Helgaas
Some devices have hardware problems related to using ASPM. Drivers for these devices use pci_disable_link_state() to prevent their device from entering L0s or L1. But on platforms where the OS doesn't have permission to manage ASPM, pci_disable_link_state() doesn't actually disable ASPM. Windows has a similar mechanism ("PciASPMOptOut"), and when the OS doesn't have control of ASPM, it doesn't actually disable ASPM either. This patch just adds a warning in dmesg about the fact that pci_disable_link_state() is doing nothing. Reported-by: Emmanuel Grumbach <egrumbach@gmail.com> Reference: https://lkml.kernel.org/r/CANUX_P3F5YhbZX3WGU-j1AGpbXb_T9Bis2ErhvKkFMtDvzatVQ@mail.gmail.com Reference: https://bugzilla.kernel.org/show_bug.cgi?id=57331 Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
2013-02-25Merge tag 'pci-v3.9-changes' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci Pull PCI changes from Bjorn Helgaas: "Host bridge hotplug - Major overhaul of ACPI host bridge add/start (Rafael Wysocki, Yinghai Lu) - Major overhaul of PCI/ACPI binding (Rafael Wysocki, Yinghai Lu) - Split out ACPI host bridge and ACPI PCI device hotplug (Yinghai Lu) - Stop caching _PRT and make independent of bus numbers (Yinghai Lu) PCI device hotplug - Clean up cpqphp dead code (Sasha Levin) - Disable ARI unless device and upstream bridge support it (Yijing Wang) - Initialize all hot-added devices (not functions 0-7) (Yijing Wang) Power management - Don't touch ASPM if disabled (Joe Lawrence) - Fix ASPM link state management (Myron Stowe) Miscellaneous - Fix PCI_EXP_FLAGS accessor (Alex Williamson) - Disable Bus Master in pci_device_shutdown (Konstantin Khlebnikov) - Document hotplug resource and MPS parameters (Yijing Wang) - Add accessor for PCIe capabilities (Myron Stowe) - Drop pciehp suspend/resume messages (Paul Bolle) - Make pci_slot built-in only (not a module) (Jiang Liu) - Remove unused PCI/ACPI bind ops (Jiang Liu) - Removed used pci_root_bus (Bjorn Helgaas)" * tag 'pci-v3.9-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/helgaas/pci: (51 commits) PCI/ACPI: Don't cache _PRT, and don't associate them with bus numbers PCI: Fix PCI Express Capability accessors for PCI_EXP_FLAGS ACPI / PCI: Make pci_slot built-in only, not a module PCI/PM: Clear state_saved during suspend PCI: Use atomic_inc_return() rather than atomic_add_return() PCI: Catch attempts to disable already-disabled devices PCI: Disable Bus Master unconditionally in pci_device_shutdown() PCI: acpiphp: Remove dead code for PCI host bridge hotplug PCI: acpiphp: Create companion ACPI devices before creating PCI devices PCI: Remove unused "rc" in virtfn_add_bus() PCI: pciehp: Drop suspend/resume ENTRY messages PCI/ASPM: Don't touch ASPM if forcibly disabled PCI/ASPM: Deallocate upstream link state even if device is not PCIe PCI: Document MPS parameters pci=pcie_bus_safe, pci=pcie_bus_perf, etc PCI: Document hpiosize= and hpmemsize= resource reservation parameters PCI: Use PCI Express Capability accessor PCI: Introduce accessor to retrieve PCIe Capabilities Register PCI: Put pci_dev in device tree as early as possible PCI: Skip attaching driver in device_add() PCI: acpiphp: Keep driver loaded even if no slots found ...
2013-02-01PCI/ASPM: Don't touch ASPM if forcibly disabledJoe Lawrence
Don't allocate and track PCIe ASPM state when "pcie_aspm=off" is specified on the kernel command line. Based-on-patch-from: Matthew Garrett <mjg59@srcf.ucam.org> Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Reviewed-by: David Bulkow <david.bulkow@stratus.com> Acked-by: Myron Stowe <myron.stowe@redhat.com>