From: Fabrizio Bertocci Date: Tue, 30 Nov 2021 04:15:40 +0000 (-0500) Subject: platform/x86: amd-pmc: Fix s2idle failures on certain AMD laptops X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=0159c7b266830a082f73f0a48da3d21b5936bbec;p=linux.git platform/x86: amd-pmc: Fix s2idle failures on certain AMD laptops commit 49201b90af818654c5506a0decc18e111eadcb66 upstream. 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@vger.kernel.org Acked-by: Shyam Sundar S K Signed-off-by: Fabrizio Bertocci Link: https://lore.kernel.org/r/CADtzkx7TdfbwtaVEXUdD6YXPey52E-nZVQNs+Z41DTx7gqMqtw@mail.gmail.com Signed-off-by: Hans de Goede Signed-off-by: Greg Kroah-Hartman --- diff --git a/drivers/platform/x86/amd-pmc.c b/drivers/platform/x86/amd-pmc.c index fc95620101e85..54b88bedecdf1 100644 --- a/drivers/platform/x86/amd-pmc.c +++ b/drivers/platform/x86/amd-pmc.c @@ -70,7 +70,7 @@ #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