exynos5xxx: use oscillator clock when changing ARM frequency
Switch ARM clock source when changing the APLL frequency to avoid
stability issues.
This is ported from https://gerrit.chromium.org/gerrit/#/c/64189/5
Signed-off-by: David Hendricks <dhendrix@chromium.org>
Change-Id: I923107555e6d3287b3694cbf9e4bb548d3e5f4a8
Reviewed-on: https://gerrit.chromium.org/gerrit/64838
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
Commit-Queue: David Hendricks <dhendrix@chromium.org>
Reviewed-on: http://review.coreboot.org/4442
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>