[coreboot-gerrit] Patch set updated for coreboot: intel/apollolake: Do not halt in poweroff if in SMM

[Furquan Shaikh (furquan@google.com)]

Furquan Shaikh (furquan at google.com) just uploaded a new patch set to gerrit, which you can find at https://review.coreboot.org/16257

-gerrit

commit 4af9371a2335058b4c8b39e0b8b75f7922b05832
Author: Furquan Shaikh <furquan at google.com>
Date:   Thu Aug 18 21:31:50 2016 -0700

    intel/apollolake: Do not halt in poweroff if in SMM
    
    Calling halt in poweroff when in SMM prevents SLP_SMI to be triggered
    preventing the system from entering sleep state. Fix this by calling
    halt only if ENV_SMM is not true.
    
    BUG=chrome-os-partner:56395
    BRANCH=None
    TEST=Verified lidclose behavior on reef.
    
    Change-Id: If116c8f4e867543abdc2ff235457c167b5073767
    Signed-off-by: Furquan Shaikh <furquan at google.com>
---
 src/soc/intel/apollolake/pmutil.c | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/src/soc/intel/apollolake/pmutil.c b/src/soc/intel/apollolake/pmutil.c
index dabc268..aaa4018 100644
--- a/src/soc/intel/apollolake/pmutil.c
+++ b/src/soc/intel/apollolake/pmutil.c
@@ -443,5 +443,12 @@ void vboot_platform_prepare_reboot(void)
 void poweroff(void)
 {
 	enable_pm1_control(SLP_EN | (SLP_TYP_S5 << SLP_TYP_SHIFT));
-	halt();
+
+	/*
+	 * Setting SLP_TYP_S5 in PM1 triggers SLP_SMI, which is handled by SMM
+	 * to transition to S5 state. If halt is called in SMM, then it prevents
+	 * the SMI handler from being triggered and system never enters S5.
+	 */
+	if (!ENV_SMM)
+		halt();
 }