kernel/drivers/pci/controller/dwc/pcie-designware-host.c, branch linux-6.9.y

PCI: dwc: Strengthen the MSI address allocation logic

2024-03-10T18:08:04Z

There can be platforms that do not use/have 32-bit DMA addresses. The current implementation of 32-bit IOVA allocation can fail for such platforms, eventually leading to the probe failure. Try to allocate a 32-bit msi_data. If this allocation fails, attempt a 64-bit address allocation. Please note that if the 64-bit MSI address is allocated, then the EPs supporting 32-bit MSI address only will not work. Link: https://lore.kernel.org/linux-pci/20240221153840.1789979-1-ajayagarwal@google.com Tested-by: Will McVicker Signed-off-by: Ajay Agarwal Signed-off-by: Krzysztof Wilczyński Reviewed-by: Manivannan Sadhasivam Reviewed-by: Serge Semin Reviewed-by: Will McVicker

PCI: dwc: Drop host prefix from struct dw_pcie_host_ops members

2024-01-06T07:51:08Z

Since the name of the dw_pcie_host_ops struct makes it obvious that it's for the PCIe Host, drop the host prefix from the struct members. [kwilczynski: commit log] Suggested-by: Serge Semin Link: https://lore.kernel.org/linux-pci/20231220053829.1921187-2-yoshihiro.shimoda.uh@renesas.com Signed-off-by: Yoshihiro Shimoda Signed-off-by: Krzysztof Wilczyński Reviewed-by: Manivannan Sadhasivam Reviewed-by: Serge Semin Reviewed-by: Thomas Petazzoni Acked-by: Heiko Stuebner Acked-by: Jesper Nilsson Acked-by: Kunihiko Hayashi Acked-by: Lei Chuanhua Acked-by: Nobuhiro Iwamatsu

PCI: dwc: Add host_post_init() callback

2023-10-14T20:02:17Z

This callback can be used by the platform drivers to do configuration once all the devices are scanned. Like changing LNKCTL of all downstream devices to enable ASPM etc... Link: https://lore.kernel.org/linux-pci/20231010155914.9516-2-manivannan.sadhasivam@linaro.org Signed-off-by: Manivannan Sadhasivam Signed-off-by: Krzysztof Wilczyński

Merge tag 'pci-v6.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci

2023-08-31T03:23:07Z

Pull PCI updates from Bjorn Helgaas: "Enumeration: - Add locking to read/modify/write PCIe Capability Register accessors for Link Control and Root Control - Use pci_dev_id() when possible instead of manually composing ID from dev->bus->number and dev->devfn Resource management: - Move prototypes for __weak sysfs resource files to linux/pci.h to fix 'no previous prototype' warnings - Make more I/O port accesses depend on HAS_IOPORT - Use devm_platform_get_and_ioremap_resource() instead of open-coding platform_get_resource() followed by devm_ioremap_resource() Power management: - Ensure devices are powered up while accessing VPD - If device is powered-up, keep it that way while polling for PME - Only read PCI_PM_CTRL register when available, to avoid reading the wrong register and corrupting dev->current_state Virtualization: - Avoid Secondary Bus Reset on NVIDIA T4 GPUs Error handling: - Remove unused pci_disable_pcie_error_reporting() - Unexport pci_enable_pcie_error_reporting(), used only by aer.c - Unexport pcie_port_bus_type, used only by PCI core VGA: - Simplify and clean up typos in VGA arbiter Apple PCIe controller driver: - Initialize pcie->nvecs (number of available MSIs) before use Broadcom iProc PCIe controller driver: - Use of_property_read_bool() instead of low-level accessors for boolean properties Broadcom STB PCIe controller driver: - Assert PERST# when probing BCM2711 because some bootloaders don't do it Freescale i.MX6 PCIe controller driver: - Add .host_deinit() callback so we can clean up things like regulators on probe failure or driver unload Freescale Layerscape PCIe controller driver: - Add support for link-down notification so the endpoint driver can process LINK_DOWN events - Add suspend/resume support, including manual PME_Turn_off/PME_TO_Ack handshake - Save Link Capabilities during probe so they can be restored when handling a link-up event, since the controller loses the Link Width and Link Speed values during reset Intel VMD host bridge driver: - Fix disable of bridge windows during domain reset; previously we cleared the base/limit registers, which actually left the windows enabled Marvell MVEBU PCIe controller driver: - Remove unused busn member Microchip PolarFlare PCIe controller driver: - Fix interrupt bit definitions so the SEC and DED interrupt handlers work correctly - Make driver buildable as a module - Read FPGA MSI configuration parameters from hardware instead of hard-coding them Microsoft Hyper-V host bridge driver: - To avoid a NULL pointer dereference, skip MSI restore after hibernate if MSI/MSI-X hasn't been enabled NVIDIA Tegra194 PCIe controller driver: - Revert 'PCI: tegra194: Enable support for 256 Byte payload' because Linux doesn't know how to reduce MPS from to 256 to 128 bytes for endpoints below a switch (because other devices below the switch might already be operating), which leads to 'Malformed TLP' errors Qualcomm PCIe controller driver: - Add DT and driver support for interconnect bandwidth voting for 'pcie-mem' and 'cpu-pcie' interconnects - Fix broken SDX65 'compatible' DT property - Configure controller so MHI bus master clock will be switched off while in ASPM L1.x states - Use alignment restriction from EPF core in EPF MHI driver - Add Endpoint eDMA support - Add MHI eDMA support - Add Snapdragon SM8450 support to the EPF MHI driversupport - Add MHI eDMA support - Add Snapdragon SM8450 support to the EPF MHI driversupport - Add MHI eDMA support - Add Snapdragon SM8450 support to the EPF MHI driversupport - Add MHI eDMA support - Add Snapdragon SM8450 support to the EPF MHI driver - Use iATU for EPF MHI transfers smaller than 4K to avoid eDMA setup latency - Add sa8775p DT binding and driver support Rockchip PCIe controller driver: - Use 64-bit mask on MSI 64-bit PCI address to avoid zeroing out the upper 32 bits SiFive FU740 PCIe controller driver: - Set the supported number of MSI vectors so we can use all available MSI interrupts Synopsys DesignWare PCIe controller driver: - Add generic dwc suspend/resume APIs (dw_pcie_suspend_noirq() and dw_pcie_resume_noirq()) to be called by controller driver suspend/resume ops, and a controller callback to send PME_Turn_Off MicroSemi Switchtec management driver: - Add support for PCIe Gen5 devices Miscellaneous: - Reorder and compress to reduce size of struct pci_dev - Fix race in DOE destroy_work_on_stack() - Add stubs to avoid casts between incompatible function types - Explicitly include correct DT includes to untangle headers" * tag 'pci-v6.6-changes' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci: (96 commits) PCI: qcom-ep: Add ICC bandwidth voting support dt-bindings: PCI: qcom: ep: Add interconnects path PCI: qcom-ep: Treat unknown IRQ events as an error dt-bindings: PCI: qcom: Fix SDX65 compatible PCI: endpoint: Add kernel-doc for pci_epc_mem_init() API PCI: epf-mhi: Use iATU for small transfers PCI: epf-mhi: Add support for SM8450 PCI: epf-mhi: Add eDMA support PCI: qcom-ep: Add eDMA support PCI: epf-mhi: Make use of the alignment restriction from EPF core PCI/PM: Only read PCI_PM_CTRL register when available PCI: qcom: Add support for sa8775p SoC dt-bindings: PCI: qcom: Add sa8775p compatible PCI: qcom-ep: Pass alignment restriction to the EPF core PCI: Simplify pcie_capability_clear_and_set_word() control flow PCI: Tidy config space save/restore messages PCI: Fix code formatting inconsistencies PCI: Fix typos in docs and comments PCI: Fix pci_bus_resetable(), pci_slot_resetable() name typos PCI: Simplify pci_dev_driver() ...

PCI: dwc: Implement generic suspend/resume functionality

2023-08-24T09:48:19Z

Introduce an helper function (dw_pcie_get_ltssm()) to retrieve SMLH_LTSS_STATE. Add common dw_pcie_suspend(resume)_noirq() API to implement the DWC controller generic suspend/resume functionality. Add a controller specific callback to send the PME_Turn_Off message (ie .pme_turn_off) for controller platform specific PME handling. Link: https://lore.kernel.org/r/20230821184815.2167131-3-Frank.Li@nxp.com Signed-off-by: Frank Li [lpieralisi@kernel.org: commit log] Signed-off-by: Lorenzo Pieralisi Acked-by: Manivannan Sadhasivam

Revert "PCI: dwc: Wait for link up only if link is started"

2023-07-26T15:49:11Z

This reverts commit da56a1bfbab55189595e588f1d984bdfb5cf5924. Bjorn Andersson, Fabio Estevam, Xiaolei Wang, and Jon Hunter reported that da56a1bfbab5 ("PCI: dwc: Wait for link up only if link is started") broke controller probing by returning an error in case the link does not come up during host initialisation, for example when the slot is empty. As explained in commit 886a9c134755 ("PCI: dwc: Move link handling into common code") and as indicated by the comment "Ignore errors, the link may come up later" in the code, waiting for link up and ignoring errors is the intended behaviour: Let's standardize this to succeed as there are usecases where devices (and the link) appear later even without hotplug. For example, a reconfigured FPGA device. Reverting the offending commit specifically fixes a regression on Qualcomm platforms like the Lenovo ThinkPad X13s which no longer reach the interconnect sync state if a slot does not have a device populated (e.g. an optional modem). Note that enabling asynchronous probing by default as was done for Qualcomm platforms by commit c0e1eb441b1d ("PCI: qcom: Enable async probe by default"), should take care of any related boot time concerns. Finally, note that the intel-gw driver is the only driver currently not providing a .start_link() callback and instead starts the link in its .host_init() callback, which may avoid an additional one-second timeout during probe by making the link-up wait conditional. If anyone cares, that can be done in a follow-up patch with a proper motivation. [bhelgaas: add Fabio Estevam, Xiaolei Wang, Jon Hunter reports] Fixes: da56a1bfbab5 ("PCI: dwc: Wait for link up only if link is started") Link: https://lore.kernel.org/r/20230706082610.26584-1-johan+linaro@kernel.org Reported-by: Bjorn Andersson Signed-off-by: Johan Hovold Reported-by: Fabio Estevam Link: https://lore.kernel.org/r/20230704122635.1362156-1-festevam@gmail.com/ Reported-by: Xiaolei Wang Link: https://lore.kernel.org/r/20230705010624.3912934-1-xiaolei.wang@windriver.com/ Reported-by: Jon Hunter Link: https://lore.kernel.org/r/6ca287a1-6c7c-7b90-9022-9e73fb82b564@nvidia.com Signed-off-by: Bjorn Helgaas Reviewed-by: Manivannan Sadhasivam Cc: Sajid Dalvi Cc: Ajay Agarwal

PCI: dwc: Wait for link up only if link is started

2023-05-26T08:45:12Z

In dw_pcie_host_init() regardless of whether the link has been started or not, the code waits for the link to come up. Even in cases where start_link() is not defined the code ends up spinning in a loop for 1 second. Since in some systems dw_pcie_host_init() gets called during probe, this one second loop for each pcie interface instance ends up extending the boot time. Wait for the link up in only if the start_link() is defined. Link: https://lore.kernel.org/r/20230412093425.3659088-1-ajayagarwal@google.com Tested-by: Will McVicker Signed-off-by: Sajid Dalvi Signed-off-by: Ajay Agarwal Signed-off-by: Lorenzo Pieralisi

PCI: dwc: Add Root Port and Endpoint controller eDMA engine support

2023-02-22T19:46:14Z

Since the DW eDMA core now supports eDMA controllers embedded in locally accessible DW PCIe Root Ports and Endpoints, register these controllers when possible. To do that the DW PCIe core driver needs to perform some preparations first. First of all, it needs to find the eDMA controller CSRs base address, whether they are accessible over the Port Logic or iATU unrolled space. Afterwards it can try to auto-detect the eDMA controller availability and number of read/write channels. If none are found the procedure silently returns without error. Secondly, the platform is supposed to provide either combined or per-channel IRQ signals. If no valid IRQs set is found, the procedure returns without error to be backward compatible with platforms where DW PCIe controllers have eDMA but lack the IRQ description. Finally, before actually probing the eDMA device we need to allocate LLP items buffers. After that the DW eDMA can be registered. If registration is successful, a message regarding the number of detected Read/Write eDMA channels will be printed to the system as is done for the iATU settings. Note: the DW PCI controller driver (either host or endpoint mode) is currently always built-in, so if the DW eDMA core is built as a module (CONFIG_DW_EDMA=m), eDMA controllers will not be registered even if the dw-edma module is later loaded. Link: https://lore.kernel.org/r/20230113171409.30470-28-Sergey.Semin@baikalelectronics.ru Signed-off-by: Serge Semin Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Reviewed-by: Manivannan Sadhasivam Acked-by: Vinod Koul

PCI: dwc: Restrict only coherent DMA mask for MSI address allocation

2023-02-22T19:46:14Z

The MSI target address must be in the lowest 4GB memory to support PCI peripherals without 64-bit MSI support. Since the allocation is done from DMA coherent memory, set only the coherent DMA mask, leaving the streaming DMA mask alone. Thus streaming DMA operations will work with no artificial limitations. It will be specifically useful for the eDMA-capable controllers so the corresponding DMA engine clients would map the DMA buffers with no need for SWIOTLB for buffers allocated above 4GB. Add a brief comment about the reason allocating the MSI target address below 4GB. Link: https://lore.kernel.org/r/20230113171409.30470-26-Sergey.Semin@baikalelectronics.ru Signed-off-by: Serge Semin Signed-off-by: Lorenzo Pieralisi Signed-off-by: Bjorn Helgaas Reviewed-by: Robin Murphy

PCI: dwc: Introduce generic resources getter

2022-11-23T15:01:55Z

Currently the DW PCIe Root Port and Endpoint CSR spaces are retrieved in the separate parts of the DW PCIe core driver. It doesn't really make sense since the both controller types have identical set of the core CSR regions: DBI, DBI CS2 and iATU/eDMA. Thus we can simplify the DW PCIe Host and EP initialization methods by moving the platform-specific registers space getting and mapping into a common method. It gets to be even more justified seeing the CSRs base address pointers are preserved in the common DW PCIe descriptor. Note all the OF-based common DW PCIe settings initialization will be moved to the new method too in order to have a single function for all the generic platform properties handling in single place. A nice side-effect of this change is that the pcie-designware-host.c and pcie-designware-ep.c drivers are cleaned up from all the direct dw_pcie storage modification, which makes the DW PCIe core, Root Port and Endpoint modules more coherent. Link: https://lore.kernel.org/r/20221113191301.5526-18-Sergey.Semin@baikalelectronics.ru Signed-off-by: Serge Semin Signed-off-by: Lorenzo Pieralisi Reviewed-by: Rob Herring