Hi, an update for the CFI flash emulation, addressing Alex' comments and adding direct mapping support. The actual code changes to the flash emulation are minimal, mostly this is about renaming and cleanups. This versions now adds some patches. 1/5 is a required fix, the last three patches add mapping support as an extension. See below. In addition to a branch with this series[1], I also put a git branch with all the changes compared to v3[2] as separate patches on the server, please have a look if you want to verify against a previous review. =============== The EDK II UEFI firmware implementation requires some storage for the EFI variables, which is typically some flash storage. Since this is already supported on the EDK II side, and looks like a generic standard, this series adds a CFI flash emulation to kvmtool. Patch 2/5 is the actual emulation code, patch 1/5 is a bug-fix for registering MMIO devices, which is needed for this device. Patches 3-5 add support for mapping the flash memory into guest, should it be in read-array mode. For this to work, patch 3/5 is cherry-picked from Alex' PCIe reassignable BAR series, to support removing a memslot mapping. Patch 4/5 adds support for read-only mappings, while patch 5/5 adds or removes the mapping based on the current state. I am happy to squash 5/5 into 2/5, if we agree that patch 3/5 should be merged either separately or the PCIe series is actually merged before this one. This is one missing piece towards a working UEFI boot with kvmtool on ARM guests, the other is to provide writable PCI BARs, which is WIP. This series alone already enables UEFI boot, but only with virtio-mmio. Cheers, Andre [1] http://www.linux-arm.org/git?p=kvmtool.git;a=log;h=refs/heads/cfi-flash/v4 [2] http://www.linux-arm.org/git?p=kvmtool.git;a=log;h=refs/heads/cfi-flash/v3 git://linux-arm.org/kvmtool.git (branches cfi-flash/v3 and cfi-flash/v4) Changelog v3 .. v4: - Rename file to cfi-flash.c (dash instead of underscore). - Unify macro names for states, modes and commands. - Enforce one or two chips only. - Comment on pow2_size() function. - Use more consistent identifier spellings. - Assign symbols to status register values. - Drop RCR register emulation. - Use numerical offsets instead of names for query offsets to match spec. - Cleanup error path and reword info message in create_flash_device_file(). - Add fix to allow non-virtio MMIO device emulations. - Support tearing down and adding read-only memslots. - Add read-only memslot mapping when in read mode. Changelog v2 .. v3: - Breaking MMIO handling into three separate functions. - Assing the flash base address in the memory map, but stay at 32 MB for now. The MMIO area has been moved up to 48 MB, to never overlap with the flash. - Impose a limit of 16 MB for the flash size, mostly to fit into the (for now) fixed memory map. - Trim flash size down to nearest power-of-2, to match hardware. - Announce forced flash size trimming. - Rework the CFI query table slightly, to add the addresses as array indicies. - Fix error handling when creating the flash device. - Fix pow2_size implementation for 0 and 1 as input values. - Fix write buffer size handling. - Improve some comments. Changelog v1 .. v2: - Add locking for MMIO handling. - Fold flash read into handler. - Move pow2_size() into generic header. - Spell out flash base address.
