┌────────────┐ ┌───────────────────────────────────┐ ┌────────────────┐ │ │ │ │ │ │ │ │ │ PCI Endpoint │ │ PCI Host │ │ │ │ │ │ │ │ │◄──┤ 1.platform_msi_domain_alloc_irqs()│ │ │ │ │ │ │ │ │ │ MSI ├──►│ 2.write_msi_msg() ├──►├─BAR<n> │ │ Controller │ │ update doorbell register address│ │ │ │ │ │ for BAR │ │ │ │ │ │ │ │ 3. Write BAR<n>│ │ │◄──┼───────────────────────────────────┼───┤ │ │ │ │ │ │ │ │ ├──►│ 4.Irq Handle │ │ │ │ │ │ │ │ │ │ │ │ │ │ │ └────────────┘ └───────────────────────────────────┘ └────────────────┘ This patches based on old https://lore.kernel.org/imx/20221124055036.1630573-1-Frank.Li@xxxxxxx/ Original patch only target to vntb driver. But actually it is common method. This patches add new API to pci-epf-core, so any EP driver can use it. Previous v2 discussion here. https://lore.kernel.org/imx/20230911220920.1817033-1-Frank.Li@xxxxxxx/ Changes in v11: - Change to use MSI_FLAG_MSG_IMMUTABLE - Link to v10: https://lore.kernel.org/r/20241204-ep-msi-v10-0-87c378dbcd6d@xxxxxxx Changes in v10: Thomas Gleixner: There are big change in pci-ep-msi.c. I am sure if go on the corrent path. The key improvement is remove only 1 function devices's limitation. I use new patch for imutable check, which relative additional feature compared to base enablement patch. - Remove patch Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all() - Add new patch irqchip/gic-v3-its: Avoid overwriting msi_prepare callback if provided by msi_domain_info - Remove only support 1 endpoint function limiation. - Create one MSI domain for each endpoint function devices. - Use "msi-map" in pci ep controler node, instead of of msi-parent. first argument is (func_no << 8 | vfunc_no) - Link to v9: https://lore.kernel.org/r/20241203-ep-msi-v9-0-a60dbc3f15dd@xxxxxxx Changes in v9 - Add patch platform-msi: Add msi_remove_device_irq_domain() in platform_device_msi_free_irqs_all() - Remove patch PCI: endpoint: Add pci_epc_get_fn() API for customizable filtering - Remove API pci_epf_align_inbound_addr_lo_hi - Move doorbell_alloc in to doorbell_enable function. - Link to v8: https://lore.kernel.org/r/20241116-ep-msi-v8-0-6f1f68ffd1bb@xxxxxxx Changes in v8: - update helper function name to pci_epf_align_inbound_addr() - Link to v7: https://lore.kernel.org/r/20241114-ep-msi-v7-0-d4ac7aafbd2c@xxxxxxx Changes in v7: - Add helper function pci_epf_align_addr(); - Link to v6: https://lore.kernel.org/r/20241112-ep-msi-v6-0-45f9722e3c2a@xxxxxxx Changes in v6: - change doorbell_addr to doorbell_offset - use round_down() - add Niklas's test by tag - rebase to pci/endpoint - Link to v5: https://lore.kernel.org/r/20241108-ep-msi-v5-0-a14951c0d007@xxxxxxx Changes in v5: - Move request_irq to epf test function driver for more flexiable user case - Add fixed size bar handler - Some minor improvememtn to see each patches's changelog. - Link to v4: https://lore.kernel.org/r/20241031-ep-msi-v4-0-717da2d99b28@xxxxxxx Changes in v4: - Remove patch genirq/msi: Add cleanup guard define for msi_lock_descs()/msi_unlock_descs() - Use new method to avoid compatible problem. Add new command DOORBELL_ENABLE and DOORBELL_DISABLE. pcitest -B send DOORBELL_ENABLE first, EP test function driver try to remap one of BAR_N (except test register bar) to ITS MSI MMIO space. Old driver don't support new command, so failure return, not side effect. After test, DOORBELL_DISABLE command send out to recover original map, so pcitest bar test can pass as normal. - Other detail change see each patches's change log - Link to v3: https://lore.kernel.org/r/20241015-ep-msi-v3-0-cedc89a16c1a@xxxxxxx Change from v2 to v3 - Fixed manivannan's comments - Move common part to pci-ep-msi.c and pci-ep-msi.h - rebase to 6.12-rc1 - use RevID to distingiush old version mkdir /sys/kernel/config/pci_ep/functions/pci_epf_test/func1 echo 16 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/msi_interrupts echo 0x080c > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/deviceid echo 0x1957 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/vendorid echo 1 > /sys/kernel/config/pci_ep/functions/pci_epf_test/func1/revid ^^^^^^ to enable platform msi support. ln -s /sys/kernel/config/pci_ep/functions/pci_epf_test/func1 /sys/kernel/config/pci_ep/controllers/4c380000.pcie-ep - use new device ID, which identify support doorbell to avoid broken compatility. Enable doorbell support only for PCI_DEVICE_ID_IMX8_DB, while other devices keep the same behavior as before. EP side RC with old driver RC with new driver PCI_DEVICE_ID_IMX8_DB no probe doorbell enabled Other device ID doorbell disabled* doorbell disabled* * Behavior remains unchanged. Change from v1 to v2 - Add missed patch for endpont/pci-epf-test.c - Move alloc and free to epc driver from epf. - Provide general help function for EPC driver to alloc platform msi irq. - Fixed manivannan's comments. To: Manivannan Sadhasivam <manivannan.sadhasivam@xxxxxxxxxx> To: Krzysztof Wilczyński <kw@xxxxxxxxx> To: Kishon Vijay Abraham I <kishon@xxxxxxxxxx> To: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> To: Arnd Bergmann <arnd@xxxxxxxx> To: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: linux-pci@xxxxxxxxxxxxxxx Cc: imx@xxxxxxxxxxxxxxx Cc: Niklas Cassel <cassel@xxxxxxxxxx> Cc: dlemoal@xxxxxxxxxx Cc: jdmason@xxxxxxxx To: Rafael J. Wysocki <rafael@xxxxxxxxxx> To: Thomas Gleixner <tglx@xxxxxxxxxxxxx> To: Anup Patel <apatel@xxxxxxxxxxxxxxxx> To: Kishon Vijay Abraham I <kishon@xxxxxxxxxx> To: Marc Zyngier <maz@xxxxxxxxxx> To: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx Signed-off-by: Frank Li <Frank.Li@xxxxxxx> --- Frank Li (7): irqchip/gic-v3-its: Avoid overwriting msi_prepare callback if provided by msi_domain_info PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller PCI: endpoint: pci-ep-msi: Add MSI address/data pair mutable check PCI: endpoint: Add pci_epf_align_inbound_addr() helper for address alignment PCI: endpoint: pci-epf-test: Add doorbell test support misc: pci_endpoint_test: Add doorbell test case tools: PCI: Add 'B' option for test doorbell drivers/irqchip/irq-gic-v3-its-msi-parent.c | 4 +- drivers/misc/pci_endpoint_test.c | 80 +++++++++++++ drivers/pci/endpoint/Makefile | 2 +- drivers/pci/endpoint/functions/pci-epf-test.c | 132 ++++++++++++++++++++++ drivers/pci/endpoint/pci-ep-msi.c | 156 ++++++++++++++++++++++++++ drivers/pci/endpoint/pci-epf-core.c | 44 ++++++++ include/linux/msi.h | 2 + include/linux/pci-ep-msi.h | 15 +++ include/linux/pci-epf.h | 19 ++++ include/uapi/linux/pcitest.h | 1 + tools/pci/pcitest.c | 16 ++- 11 files changed, 468 insertions(+), 3 deletions(-) --- base-commit: b66d92bfe0a9e86a622e77a12e420b69af633d1d change-id: 20241010-ep-msi-8b4cab33b1be Best regards, --- Frank Li <Frank.Li@xxxxxxx>