Hi Will, Julien, On 3/15/21 3:33 PM, Andre Przywara wrote: > Hi, > > this version is addressing Alexandru's comments, fixing mostly minor > issues in the naming scheme. The biggest change is to keep the > ioport__read/ioport_write wrappers for the serial device. > For more details see the changelog below. > ============== > > At the moment we use two separate code paths to handle exits for > KVM_EXIT_IO (ioport.c) and KVM_EXIT_MMIO (mmio.c), even though they > are semantically very similar. Because the trap handler callback routine > is different, devices need to decide on one conduit or need to provide > different handler functions for both of them. > > This is not only unnecessary code duplication, but makes switching > devices from I/O port to MMIO a tedious task, even though there is no > real difference between the two, especially on ARM and PowerPC. > > For ARM we aim at providing a flexible memory layout, and also have > trouble with the UART and RTC device overlapping with the PCI I/O area, > so it seems indicated to tackle this once and for all. > > The first three patches do some cleanup, to simplify things later. > > Patch 04/22 lays the groundwork, by extending mmio.c to be able to also > register I/O port trap handlers, using the same callback prototype as > we use for MMIO. > > The next 14 patches then convert devices that use the I/O port > interface over to the new joint interface. This requires to rework > the trap handler routine to adhere to the same prototype as the existing > MMIO handlers. For most devices this is done in two steps: a first to > introduce the reworked handler routine, and a second to switch to the new > joint registration routine. For some devices the first step is trivial, > so it's done in one patch. > > Patch 19/22 then retires the old I/O port interface, by removing ioport.c > and friends. > Patch 20/22 uses the opportunity to clean up the memory map description, > also declares a new region (from 16MB on), where the final two patches > switch the UART and the RTC device to. They are now registered > on the MMIO "bus", when running on ARM or arm64. This moves them away > from the first 64KB, so they are not in the PCI I/O area anymore. I have reviewed the series and everything looks fine to me and ready to be merged. I have also ran the following tests: - On my x86_64 desktop, I ran a guest with --sdl, to exercise the vesa device. - On a rockpro64, I ran kvm-unit-tests for arm64 and arm (kvmtool was compiled for arm64); I also ran Linux guests using 4k and 64k pages with and without --force-pci. - On a Seattle machine, I did PCI passthrough for an Intel 82574L network card and ran Linux guests using 4k and 64k pages with and without --force-pci. - On an odroid-c4 (4 x Cortex-A55), I ran Linux guests using 4k, 16k and 64k pages with and without --force-pci. With this series merged, everything will be in place to bring back the patch that adds PCI Express 1.1 support for arm/arm64 [1]. The patch was previously dropped because the RTC and UART were overlapping with the PCI I/O space and EDK2 doesn't not understand PCI I/O bus addresses above 64k, but this series fixes that by moving the addresses of the two devices. [1] https://www.spinics.net/lists/kvm/msg211304.html Thanks, Alex
