Hi Will, On 3/18/20 9:58 PM, Will Deacon wrote: > On Fri, Feb 21, 2020 at 04:55:32PM +0000, Andre Przywara wrote: >> From: Raphael Gault <raphael.gault@xxxxxxx> >> >> 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, we add a CFI flash >> emulation to kvmtool. >> This is backed by a file, specified via the --flash or -F command line >> option. Any flash writes done by the guest will immediately be reflected >> into this file (kvmtool mmap's the file). >> The flash will be limited to the nearest power-of-2 size, so only the >> first 2 MB of a 3 MB file will be used. >> >> This implements a CFI flash using the "Intel/Sharp extended command >> set", as specified in: >> - JEDEC JESD68.01 >> - JEDEC JEP137B >> - Intel Application Note 646 >> Some gaps in those specs have been filled by looking at real devices and >> other implementations (QEMU, Linux kernel driver). >> >> At the moment this relies on DT to advertise the base address of the >> flash memory (mapped into the MMIO address space) and is only enabled >> for ARM/ARM64. The emulation itself is architecture agnostic, though. >> >> This is one missing piece toward a working UEFI boot with kvmtool on >> ARM guests, the other is to provide writable PCI BARs, which is WIP. >> >> Signed-off-by: Raphael Gault <raphael.gault@xxxxxxx> >> [Andre: rewriting and fixing] >> Signed-off-by: Andre Przywra <andre.przywara@xxxxxxx> >> --- >> Hi, >> >> an update fixing Alexandru's review comments (many thanks for those!) >> The biggest change code-wise is the split of the MMIO handler into three >> different functions. Another significant change is the rounding *down* of >> the present flash file size to the nearest power-of-two, to match flash >> hardware chips and Linux' expectations. > Alexandru -- are you happy with this now? I really appreciate taking the time to look at it, but at the moment I'm busy testing v3 of the reassignable BARs and PCIE support [1]. I'll try to send the patches as soon as possible, then I'll review this patch. [1] https://www.spinics.net/lists/kvm/msg204878.html Thanks, Alex > > Will _______________________________________________ kvmarm mailing list kvmarm@xxxxxxxxxxxxxxxxxxxxx https://lists.cs.columbia.edu/mailman/listinfo/kvmarm
