On Mon, Oct 21, 2019 at 7:24 AM Simon Glass <s...@chromium.org> wrote: > > In TPL we try to minimise code size so do not include the PCI subsystem. > We can use fixed BARs and drivers can directly program the devices that > they need. > > However we do need to bind the devices on the PCI bus and without PCI this > does not ordinarily happen. As a work-around, define a fake PCI bus which > does this binding, but no other PCI operations. This is a convenient way > to ensure that we can use the same device tree for TPL, SPL and U-Boot > proper: > > TPL - CONFIG_TPL_PCI is not set (no auto-config, fake PCI bus) > SPL - CONFIG_SPL_PCI is set (no auto-config but with real PCI bus) > U-Boot - CONFIG_PCI is set (full auto-config after relocation)
PCI(e) bus is present in a lot of SoCs (not exclusively x86). Perhaps better idea is to have something like lib/pci.c with minimum support for PCI type 1 and probably PCI type 2 accessors and other very basic functions. -- With Best Regards, Andy Shevchenko _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
