┌────────────┐ ┌───────────────────────────────────┐ ┌────────────────┐ │ │ │ │ │ │ │ │ │ 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 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: cassel@xxxxxxxxxx Cc: dlemoal@xxxxxxxxxx Cc: maz@xxxxxxxxxx Cc: tglx@xxxxxxxxxxxxx Cc: jdmason@xxxxxxxx Signed-off-by: Frank Li <Frank.Li@xxxxxxx> --- Frank Li (5): PCI: endpoint: Add pci_epc_get_fn() API for customizable filtering PCI: endpoint: Add RC-to-EP doorbell support using platform MSI controller 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/misc/pci_endpoint_test.c | 63 +++++++++++++ drivers/pci/endpoint/Makefile | 2 +- drivers/pci/endpoint/functions/pci-epf-test.c | 104 +++++++++++++++++++++ drivers/pci/endpoint/pci-ep-msi.c | 128 ++++++++++++++++++++++++++ drivers/pci/endpoint/pci-epc-core.c | 23 ++++- include/linux/pci-ep-msi.h | 15 +++ include/linux/pci-epc.h | 2 + include/linux/pci-epf.h | 19 ++++ include/uapi/linux/pcitest.h | 1 + tools/pci/pcitest.c | 16 +++- 10 files changed, 369 insertions(+), 4 deletions(-) --- base-commit: f231847d7f5a171be4566099f654521606b3ec37 change-id: 20241010-ep-msi-8b4cab33b1be Best regards, --- Frank Li <Frank.Li@xxxxxxx>
