Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux

Pull more powerpc updates from Michael Ellerman:
 "Here's some more updates for powerpc for 3.18.

  They are a bit late I know, though must are actually bug fixes.  In my
  defence I nearly cut the top of my finger off last weekend in a
  gruesome bike maintenance accident, so I spent a good part of the week
  waiting around for doctors.  True story, I can send photos if you like :)

  Probably the most interesting fix is the sys_call_table one, which
  enables syscall tracing for powerpc.  There's a fix for HMI handling
  for old firmware, more endian fixes for firmware interfaces, more EEH
  fixes, Anton fixed our routine that gets the current stack pointer,
  and a few other misc bits"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mpe/linux: (22 commits)
  powerpc: Only do dynamic DMA zone limits on platforms that need it
  powerpc: sync pseries_le_defconfig with pseries_defconfig
  powerpc: Add printk levels to setup_system output
  powerpc/vphn: NUMA node code expects big-endian
  powerpc/msi: Use WARN_ON() in msi bitmap selftests
  powerpc/msi: Fix the msi bitmap alignment tests
  powerpc/eeh: Block CFG upon frozen Shiner adapter
  powerpc/eeh: Don't collect logs on PE with blocked config space
  powerpc/eeh: Block PCI config access upon frozen PE
  powerpc/pseries: Drop config requests in EEH accessors
  powerpc/powernv: Drop config requests in EEH accessors
  powerpc/eeh: Rename flag EEH_PE_RESET to EEH_PE_CFG_BLOCKED
  powerpc/eeh: Fix condition for isolated state
  powerpc/pseries: Make CPU hotplug path endian safe
  powerpc/pseries: Use dump_stack instead of show_stack
  powerpc: Rename __get_SP() to current_stack_pointer()
  powerpc: Reimplement __get_SP() as a function not a define
  powerpc/numa: Add ability to disable and debug topology updates
  powerpc/numa: check error return from proc_create
  powerpc/powernv: Fallback to old HMI handling behavior for old firmware
  ...

1 files changed, 21 insertions, 0 deletions

diff --git a/arch/powerpc/platforms/powernv/opal.c b/arch/powerpc/platforms/powernv/opal.c
index b642b0562f5a..d019b081df9d 100644
--- a/arch/powerpc/platforms/powernv/opal.c
+++ b/arch/powerpc/platforms/powernv/opal.c
@@ -194,6 +194,27 @@ static int __init opal_register_exception_handlers(void)
 	 * fwnmi area at 0x7000 to provide the glue space to OPAL
 	 */
 	glue = 0x7000;
+
+	/*
+	 * Check if we are running on newer firmware that exports
+	 * OPAL_HANDLE_HMI token. If yes, then don't ask OPAL to patch
+	 * the HMI interrupt and we catch it directly in Linux.
+	 *
+	 * For older firmware (i.e currently released POWER8 System Firmware
+	 * as of today <= SV810_087), we fallback to old behavior and let OPAL
+	 * patch the HMI vector and handle it inside OPAL firmware.
+	 *
+	 * For newer firmware (in development/yet to be released) we will
+	 * start catching/handling HMI directly in Linux.
+	 */
+	if (!opal_check_token(OPAL_HANDLE_HMI)) {
+		pr_info("opal: Old firmware detected, OPAL handles HMIs.\n");
+		opal_register_exception_handler(
+				OPAL_HYPERVISOR_MAINTENANCE_HANDLER,
+				0, glue);
+		glue += 128;
+	}
+
 	opal_register_exception_handler(OPAL_SOFTPATCH_HANDLER, 0, glue);
 #endif