From 3914a316c3d3ab1ba45fe33394f37aaefdc62d61 Mon Sep 17 00:00:00 2001 From: Jens Rottmann Date: Tue, 19 Feb 2013 15:01:06 +0100 Subject: AMD SB800: don't switch clock from 14 to 48 MHz for smscsuperio The power up default for the 14M_25M_48M_OSC switchable clock output ball of the SB800 chipset is 14 MHz. sb800/bootblock.c changes this to 48 MHz, which is the correct value for almost all SIOs. However, not for 'smscsuperio' (SMSC SCH311x), which needs the original 14 MHz and is not configurable for other clock speeds. A wrong SIO clock supply results in funny RS232 output (wrong bit speed) and non-working PS/2. We could switch back to 14 MHz in the mainboard's romstage.c, but then the clock frequency would change twice. The resulting short 48 MHz burst causes a handful of rubbish characters on RS232 on every boot until the SIO clock has stabilized again. This patch skips the SB800 clock switch if the SIO Kconfig requests 14 MHz. This does not affect any boards currently in the repository (yet). Change-Id: Icff41fd88dc41c08f3700ab4f786852f04eff2a4 Signed-off-by: Jens Rottmann Reviewed-on: http://review.coreboot.org/2454 Tested-by: build bot (Jenkins) Reviewed-by: Paul Menzel Reviewed-by: Martin Roth --- src/superio/Kconfig | 3 +++ 1 file changed, 3 insertions(+) (limited to 'src/superio/Kconfig') diff --git a/src/superio/Kconfig b/src/superio/Kconfig index 4e05a8ef35..32e60bb367 100644 --- a/src/superio/Kconfig +++ b/src/superio/Kconfig @@ -17,6 +17,9 @@ ## Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA ## +config SUPERIO_WANTS_14MHZ_CLOCK + bool + source src/superio/fintek/Kconfig source src/superio/intel/Kconfig source src/superio/ite/Kconfig -- cgit v1.2.3