Hi, On 11/17/22 17:06, Limonciello, Mario wrote: > [Public] > > > >> -----Original Message----- >> From: Hans de Goede <hdegoede@xxxxxxxxxx> >> Sent: Thursday, November 17, 2022 08:06 >> To: Limonciello, Mario <Mario.Limonciello@xxxxxxx>; S-k, Shyam-sundar >> <Shyam-sundar.S-k@xxxxxxx> >> Cc: Mahapatra, Rajib <Rajib.Mahapatra@xxxxxxx>; Raul Rangel >> <rrangel@xxxxxxxxxxxx>; Mark Gross <markgross@xxxxxxxxxx>; platform- >> driver-x86@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx >> Subject: Re: [PATCH] platform/x86/amd: pmc: Add a workaround for an s0i3 >> issue on Cezanne >> >> Hi Mario, >> >> On 11/16/22 16:43, Mario Limonciello wrote: >>> 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: "Mahapatra, Rajib" <Rajib.Mahapatra@xxxxxxx> >>> Cc: "Raul Rangel" <rrangel@xxxxxxxxxxxx> >>> Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> >> >> Thank you for your patch, I've applied this patch to my review-hans >> branch: >> https://git.k ernel.org%2Fpub%2Fscm%2Flinux%2Fkernel%2Fgit%2Fpdx86%2Fplatform- >> drivers-x86.git%2Flog%2F%3Fh%3Dreview- >> hans&data=05%7C01%7Cmario.limonciello%40amd.com%7C674f8bf7a8 >> 114f83a3b408dac8a4d941%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C >> 0%7C638042907591739047%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLj >> AwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C% >> 7C%7C&sdata=XYwl%2FOvUFy%2Bgz9EY9oa35M%2BkLf%2Bud8PKXynQ >> FlrUdoE%3D&reserved=0 >> >> Please let me know if it important to get this as a fix into 6.1, >> I wasn't really planning on doing any more fixes pull-reqs for 6.1, >> but I can do one if necessary. >> > > AFAIK it's a corner case. I think it can wait until 6.2, but I think it should probably > be Cc to 6.1 stable (which has the ability to run code in the check()) phase. Ok, I have added a: Cc: stable@xxxxxxxxxxxxxxx # 6.1 to the commit msg. Regards, Hans >>> --- >>> drivers/platform/x86/amd/pmc.c | 6 ++++++ >>> 1 file changed, 6 insertions(+) >>> >>> diff --git a/drivers/platform/x86/amd/pmc.c >> b/drivers/platform/x86/amd/pmc.c >>> index ef4ae977b8e0..439d282aafd1 100644 >>> --- a/drivers/platform/x86/amd/pmc.c >>> +++ b/drivers/platform/x86/amd/pmc.c >>> @@ -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); >>> >
