On 2/26/24 11:12 PM, Ethan Zhao wrote: > On 2/27/2024 2:35 PM, Kuppuswamy Sathyanarayanan wrote: >> Hi, >> >> On 2/26/24 10:18 PM, Ethan Zhao wrote: >>> On 2/23/2024 6:15 AM, Bjorn Helgaas wrote: >>>> From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> >>>> >>>> Previously we could request control of DPC without AER, which is illegal >>>> per spec. Also, we could enable CONFIG_PCIE_DPC without CONFIG_PCIE_EDR, >>>> which is also illegal. This series addresses both. >>> I have a question here, how to understand the relationship EDR & AER ? >>> somewhere EDR touches AER status without checking _OSC granted bits, >>> such as >>> pci_aer_raw_clear_status(edev); >> >> Which_OSC bits? >> >> EDR code will only get triggered if OS advertises the EDR support (which >> also means OS supports AER and DPC), and both AER and DPC is owned by >> the firmware. During the EDR notification, the OS is allowed to touch AER > > Means no need to check if host->native_aer ? why checked in > pcie_do_recovery() ? pcie_do_recovery() can be called form EDR (FF) or native path. That check is used to skip device status clearing in FF mode. You can find details about it in https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/drivers/pci/pcie/err.c?id=068c29a248b6ddbfdf7bb150b547569759620d36 > > Thanks, > Ethan > >> and DPC registers. So there is no problem with EDR code using AER routines. >> >> >>> sometimes EDR calling AER with host->native_aer checked, like >>> >>> pcie_do_recovery() >>> { >>> ... >>> if (host->native_aer || pcie_ports_native) { >>> pcie_clear_device_status(dev); >>> pci_aer_clear_nonfatal_status(dev); >>> } >>> ... >>> } >>> >>> That is really confusing. could we do some cleanup to eliminate it ? >>> such as seperate AER code into common code and runtime part. >>> >>> >>> Thanks, >>> Ethan >>> >>>> Bjorn Helgaas (3): >>>> PCI/DPC: Request DPC only if also requesting AER >>>> PCI/DPC: Remove CONFIG_PCIE_EDR >>>> PCI/DPC: Encapsulate pci_acpi_add_edr_notifier() >>>> >>>> drivers/acpi/pci_root.c | 22 ++++++++++++---------- >>>> drivers/pci/pci.h | 4 ++++ >>>> drivers/pci/pcie/Kconfig | 14 ++++---------- >>>> drivers/pci/pcie/Makefile | 5 ++++- >>>> drivers/pci/pcie/dpc.c | 10 ---------- >>>> include/linux/pci-acpi.h | 8 -------- >>>> 6 files changed, 24 insertions(+), 39 deletions(-) >>>> > -- Sathyanarayanan Kuppuswamy Linux Kernel Developer
