[PATCH 0/3] Add RC-to-EP doorbell with platform MSI controller
Frank Li
Frank.Li at nxp.com
Wed Apr 26 13:34:33 PDT 2023
┌────────────┐ ┌───────────────────────────────────┐ ┌────────────────┐
│ │ │ │ │ │
│ │ │ 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@nxp.com/
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.
The key point is comments from Thomas Gleixner, who suggest use new
PCI/IMS. But arm platform change still not be merged yet.
git://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git devmsi-v2-arm
So I still use existed method implement RC to EP doorbell.
If Thomas Gleixner want to continue work on devmsi-v2-arm, I can help test
and update this patch.
Frank Li (3):
PCI: endpoint: Add RC-to-EP doorbell support using platform MSI
controller
misc: pci_endpoint_test: Add doorbell test case
tools: PCI: Add 'B' option for test doorbell
drivers/misc/pci_endpoint_test.c | 41 +++++++++++
drivers/pci/endpoint/pci-epf-core.c | 109 ++++++++++++++++++++++++++++
include/linux/pci-epf.h | 16 ++++
include/uapi/linux/pcitest.h | 1 +
tools/pci/pcitest.c | 16 +++-
5 files changed, 182 insertions(+), 1 deletion(-)
--
2.34.1
More information about the linux-arm-kernel
mailing list