coreboot-kgpe-d16/payloads/libpayload/drivers
Nico Huber a69d682a0b libpayload/keyboard: Revise scancode set and translation config
Some background first: The original XT keyboards used what we call
scancode set #1 today. The PC/AT keyboards introduced scancode set #2,
but for compatibility, its controller translated scancodes back to
set #1 by default. Newer keyboards (maybe all we have to deal with)
also support switching the scancode set.

This means the translation option in the controller and the scancode
set selection in the keyboard have to match. In libpayload, we only
support set #1 scancodes. So we either need the controller's trans-
lation on and set #2 selected in the keyboard, or the controller's
translation off and set #1 selected in the keyboard.

Valid configurations:
* SET #1 + XLATE off
* SET #2 + XLATE on

Both with and without the PC_KEYBOARD_AT_TRANSLATED option, we were
only configuring one of the two settings, leaving room for invalid
configurations. With this change, we try to select scancode set #2
first, which seems to be the most supported one, and configure the
controller's translation accordingly. We try to fall back to set #1
on failure.

We also keep translation disabled during configuration steps to
ensure that the controller doesn't accidentally translate confi-
guration data.

On the coreboot side, we leave the controller's translation at its
default setting, unless DRIVERS_PS2_KEYBOARD is enabled. The latter
enables the translation unconditionally. For QEMU this means that
the option effectively toggles the translation, as QEMU's controller
has it disabled by default. This probably made a lot of earlier
testing inconsistent.

Fixes: commit a95a6bf646 (libpayload/drivers/i8402/kbd: Fix qemu)
       The reset introduced there effectively reverted the scancode
       selection made before (because 2 is the default). It's unclear
       if later changes to the code were only necessary to work
       around it.

Change-Id: Iad85af516a7b9f9c0269ff9652ed15ee81700057
Signed-off-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46724
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
2020-12-23 03:29:32 +00:00
..
i8042 libpayload/keyboard: Revise scancode set and translation config 2020-12-23 03:29:32 +00:00
serial payloads: Drop unneeded empty lines 2020-09-21 16:20:57 +00:00
storage libpayload: storage.c: remove unneeded #if CONFIG() 2020-11-09 07:23:20 +00:00
timer
udc payloads: Drop unneeded empty lines 2020-09-21 16:20:57 +00:00
usb libpayload/usb: Fix printf format string mismatches in debug messages 2020-11-22 22:34:52 +00:00
video payloads: Drop unneeded empty lines 2020-09-21 16:20:57 +00:00
Makefile.inc
cbmem_console.c libpayload: Cache physical cbmem console address 2020-08-24 09:12:47 +00:00
hid.c
mouse_cursor.c
nvram.c payloads: Drop unneeded empty lines 2020-09-21 16:20:57 +00:00
options.c libpayload: use PRIu64 type to print u64 2020-09-30 10:16:44 +00:00
pci.c
speaker.c