Commit e4678483 authored by Mario Limonciello's avatar Mario Limonciello Committed by Hans de Goede
Browse files

platform/x86/amd: pmc: Add a workaround for an s0i3 issue on Cezanne 



Cezanne platforms under the right circumstances have a synchronization
problem where attempting to enter s2idle may fail if the x86 cores are
put into HLT before hardware resume from the previous attempt has
completed.

To avoid this issue add a 10-20ms delay before entering s2idle another
time. This workaround will only be applied on interrupts that wake the
hardware but don't break the s2idle loop.

Cc: stable@vger.kernel.org # 6.1
Cc: "Mahapatra, Rajib" <Rajib.Mahapatra@amd.com>
Cc: "Raul Rangel" <rrangel@chromium.org>
Signed-off-by: default avatarMario Limonciello <mario.limonciello@amd.com>
Link: https://lore.kernel.org/r/20221116154341.13382-1-mario.limonciello@amd.com


Reviewed-by: default avatarHans de Goede <hdegoede@redhat.com>
Signed-off-by: default avatarHans de Goede <hdegoede@redhat.com>
parent b44fd994

drivers/platform/x86/amd/pmc.c

+6 −0
Original line number Diff line number Diff line
@@ -739,8 +739,14 @@ static void amd_pmc_s2idle_prepare(void) 
static void amd_pmc_s2idle_check(void)

{

	struct amd_pmc_dev *pdev = &pmc;

	struct smu_metrics table;

	int rc;



	/* CZN: Ensure that future s0i3 entry attempts at least 10ms passed */

	if (pdev->cpu_id == AMD_CPU_ID_CZN && !get_metrics_table(pdev, &table) &&

	    table.s0i3_last_entry_status)

		usleep_range(10000, 20000);



	/* Dump the IdleMask before we add to the STB */

	amd_pmc_idlemask_read(pdev, pdev->dev, NULL);