tree 8dcf8092bcc0091915664d2e8e77b4a568a355d9
parent cf1f4bb343ca1d19e09c89432367274786dfa873
author Simon Glass <sjg@chromium.org> 1683240900 -0600
committer Bin Meng <bmeng@tinylab.org> 1683771929 +0800

x86: Allow locating the UART from ACPI tables

When coreboot does not pass a UART in its sysinfo struct, there is no
easy way to find it out.

Since coreboot does not actually init the serial device when serial is
disabled, it is not possible to make it add this information to the
sysinfo table.

Add a way to obtain this information from the DBG2 ACPI table, which is
normally set up by coreboot.

For now this only supports a memory-mapped 16550-style UART.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>