On Fri, 2022-09-02 at 16:12 +1000, Benjamin Herrenschmidt wrote: > This series improves our legacy serial support to add the ability > to use MMIO based serial ports on x86 and to use ACPI's SPCR to > automatically configure the default port. > > An MMIO serial port can be specified explicitely using the > "mmio," prefix for the --port argument to the 'serial' command, > the register access size can also be specified via a suffix, > and when 'serial' is used without arguments, it will try to use > an ACPI SPCR entry (if any) to add the default port and configure > it appropriately (speed, parity etc...)
I forgot to mention that typically MMIO UARTs are found on AWS EC2 "metal" instances, whose firmware also conveniently populates SPCR. This allows grub serial to work on these. Cheers, Ben. _______________________________________________ Grub-devel mailing list Grub-devel@gnu.org https://lists.gnu.org/mailman/listinfo/grub-devel
