On 06/03/2021 01.43, Arnd Bergmann wrote:
- setting ioremap() on PCI buses non-posted only makes them only slower but not more reliable, because the non-posted flag on the bus is discarded by the PCI host bridge.
Note that this doesn't work here *anyway*. The fabric is picky in both directions: thou shalt use nGnRnE for on-SoC MMIO and nGnRE for PCIe windows, or else, SError.
Since these devices can support *any* PCI device via Thunderbolt, making PCI drivers be the oddball ones needing special APIs would mean hundreds of changes needed - the vast majority of PCI drivers in the kernel use plain ioremap variants that don't have any flags to look at.
-- Hector Martin (marcan@xxxxxxxxx) Public Key: https://mrcn.st/pub
