The patch below does not apply to the 5.16-stable tree.
If someone wants it applied there, or to any other stable or longterm
tree, then please email the backport, including the original git commit
id to <stable(a)vger.kernel.org>.
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From a602f5111fdd3d8a8ea2ac9e61f1c047d9794062 Mon Sep 17 00:00:00 2001
From: Fabrizio Bertocci <fabriziobertocci(a)gmail.com>
Date: Mon, 29 Nov 2021 23:15:40 -0500
Subject: [PATCH] platform/x86: amd-pmc: Fix s2idle failures on certain AMD
laptops
On some AMD hardware laptops, the system fails communicating with the
PMC when entering s2idle and the machine is battery powered.
Hardware description: HP Pavilion Aero Laptop 13-be0097nr
CPU: AMD Ryzen 7 5800U with Radeon Graphics
GPU: 03:00.0 VGA compatible controller [0300]: Advanced Micro Devices,
Inc. [AMD/ATI] Device [1002:1638] (rev c1)
Detailed description of the problem (and investigation) here:
https://gitlab.freedesktop.org/drm/amd/-/issues/1799
Patch is a single line: reduce the polling delay in half, from 100uSec
to 50uSec when waiting for a change in state from the PMC after a
write command operation.
After changing the delay, I did not see a single failure on this
machine (I have this fix for now more than one week and s2idle worked
every single time on battery power).
Cc: stable(a)vger.kernel.org
Acked-by: Shyam Sundar S K <Shyam-sundar.S-k(a)amd.com>
Signed-off-by: Fabrizio Bertocci <fabriziobertocci(a)gmail.com>
Link: https://lore.kernel.org/r/CADtzkx7TdfbwtaVEXUdD6YXPey52E-nZVQNs+Z41DTx7gqMq…
Signed-off-by: Hans de Goede <hdegoede(a)redhat.com>
diff --git a/drivers/platform/x86/amd-pmc.c b/drivers/platform/x86/amd-pmc.c
index b7e50ed050a8..841c44cd64c2 100644
--- a/drivers/platform/x86/amd-pmc.c
+++ b/drivers/platform/x86/amd-pmc.c
@@ -76,7 +76,7 @@
#define AMD_CPU_ID_CZN AMD_CPU_ID_RN
#define AMD_CPU_ID_YC 0x14B5
-#define PMC_MSG_DELAY_MIN_US 100
+#define PMC_MSG_DELAY_MIN_US 50
#define RESPONSE_REGISTER_LOOP_MAX 20000
#define SOC_SUBSYSTEM_IP_MAX 12