On Tue, 8 Apr 2025, Hans Zhang wrote: > > > On 2025/4/8 01:03, Ilpo Järvinen wrote: > > > Hi Ilpo, > > > > > > The [v9 3/6]patch I plan to submit is as follows, please review it. > > > > > > From 6da415d130e76b57ecf401f14bf0b66f20407839 Mon Sep 17 00:00:00 2001 > > > From: Hans Zhang<18255117159@xxxxxxx> > > > Date: Fri, 4 Apr 2025 00:20:29 +0800 > > > Subject: [v9 3/6] PCI: Refactor capability search into common macros > > > > > > - Capability search is done both in PCI core and some controller drivers. > > > - PCI core's cap search func requires PCI device and bus structs exist. > > > - Controller drivers cannot use PCI core's cap search func as they > > > need to find capabilities before they instantiated the PCI device & bus > > > structs. > > > > > > - Move capability search into a macro so it can be reused where normal > > > PCI config space accessors cannot yet be used due to lack of the > > > instantiated PCI dev. > > > - Instead, give the config space reading function as an argument to the > > > new macro. > > > - Convert PCI core to use the new macro. > > None of these bullets are true lists so please write them as normal > > English paragraphs. Also please extend some of shortened words lke "cap" > > --> "Capability", "PCI dev" -> PCI Device (for terms, the capitalization > > of the first letter, you should follow what the PCI specs use). > > > > Dear Ilpo, > > Thank you very much for your reply. Is it OK to modify it like this? > > The PCI Capability search functionality is duplicated across the PCI core and > several controller drivers. The core's current implementation > requires fully initialized PCI device and bus structures, which prevents > controller drivers from using it during early initialization phases before > these structures are available. > > Move the Capability search logic into a header-based macro that accepts a > config space accessor function as an argument. This enables controller > drivers to perform Capability discovery using their early access mechanisms > prior to full device initialization while maintaining the original search > behavior. ... while maintaining ... -> ... while sharing the Capability search code. > > Convert the existing PCI core Capability search implementation to use this new > macro I think the rest of this paragraph after this are unnecessary. > , eliminating code duplication. The refactoring preserves the original > functionality without behavioral changes, while allowing both the core and > drivers to share common Capability discovery logic. Other than that, it seemed good enough for me. -- i. > > > The macros now implement, parameterized by the config access method. The > > > PCI core functions are converted to utilize these macros with the standard > > > pci_bus_read_config accessors. Controller drivers can later use the same > > > macros with their early access mechanisms while maintaining the existing > > > protection against infinite loops through preserved TTL checks. > > > > > > The ttl parameter was originally an additional safeguard to prevent > > > infinite loops in corrupted config space. However, the > > > PCI_FIND_NEXT_CAP_TTL macro already enforces a TTL limit internally. > > > Removing redundant ttl handling simplifies the interface while maintaining > > > the safety guarantee. This aligns with the macro's design intent of > > > encapsulating TTL management. > > > > > > Signed-off-by: Hans Zhang<18255117159@xxxxxxx> > > > --- > > > drivers/pci/pci.c | 70 +++++--------------------------------- > > > drivers/pci/pci.h | 86 +++++++++++++++++++++++++++++++++++++++++++++++ > > > 2 files changed, 95 insertions(+), 61 deletions(-) >
