Commits
Mahesh Salgaonkar committed 6507955c978
powerpc/powernv: Fallback to old HMI handling behavior for old firmware Recently we moved HMI handling into Linux kernel instead of taking HMI directly in OPAL. This new change is dependent on new OPAL call for HMI recovery which was introduced in newer firmware. While this new change works fine with latest OPAL firmware, we broke the HMI handling if we run newer kernel on old OPAL firmware that results in system hang. This patch fixes this issue by falling back to old HMI behavior on older OPAL firmware. This patch introduces a check for opal token OPAL_HANDLE_HMI to see if we are running on newer firmware or old firmware. On newer firmware this check would return OPAL_TOKEN_PRESENT, otherwise we are running on old firmware and fallback to old HMI behavior. Old firmware: POWER8 System Firmware Release as of today <= SV810_087 Action: Let OPAL handle HMIs Newer firmware: in development/yet to be released. Action: Let Linux host handle HMIs. This patch depends on opal check token patch posted at ppc-devel https://lists.ozlabs.org/pipermail/linuxppc-dev/2014-August/120224.html Signed-off-by: Mahesh Salgaonkar <mahesh@linux.vnet.ibm.com> [mpe: Minor comment and printk rewording] Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>