Type 0x01 was introduced with the ACPI DBGP table and type 0x12 was introduced
with the ACPI DBG2 table. Type 0x12 is used by the ACPI SPCR table on recent
AWS bare-metal instances (c6i/c7i). Also give each debug type a proper name.
Signed-off-by: Udo Steinberg <udo@hypervisor.org>
Reviewed-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
According to commit 0231d00082 (ACPI: SPCR: Make SPCR available to x86)
to the Linux kernel, "On x86, many systems have a valid SPCR table but the
table version is not 2 so the table version check must be a warning."
Signed-off-by: Glenn Washburn <development@efficientek.com>
Reviewed-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
The various functions to add a port used to return port->name, and
the callers would immediately iterate all registered ports to "find"
the one just created by comparing that return value with ... port->name.
This is a waste of cycles and code. Instead, have those functions
return "port" directly.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
It is common for PCI based UARTs to use larger than one byte access
sizes. This adds support for this and uses the information present
in SPCR accordingly.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
"serial auto" is now equivalent to just "serial" and will use the
SPCR to discover the port if present, otherwise defaults to "com0"
as before.
This allows to support MMIO ports specified by ACPI which is needed
on AWS EC2 "metal" instances, and will enable GRUB to pickup the
port configuration specified by ACPI in other cases.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
Udo Steinberg