From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 432FBC6FD18 for ; Wed, 29 Mar 2023 12:34:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229695AbjC2MeF (ORCPT ); Wed, 29 Mar 2023 08:34:05 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229448AbjC2MeE (ORCPT ); Wed, 29 Mar 2023 08:34:04 -0400 Received: from mail-pg1-x52d.google.com (mail-pg1-x52d.google.com [IPv6:2607:f8b0:4864:20::52d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D92FA469C for ; Wed, 29 Mar 2023 05:34:02 -0700 (PDT) Received: by mail-pg1-x52d.google.com with SMTP id d10so9152905pgt.12 for ; Wed, 29 Mar 2023 05:34:02 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=semihalf.com; s=google; t=1680093242; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=kpAhLQZY7Czy6y1NGq4c0NlbJ5rELrH1U8V8KvW/EPk=; b=Sfj6WKW6hh8yUQXVKEjK8xSx5KBZQTD5cOxgkAIdmAGHUF8bhz5dbFq5rfV0if5Mp3 xVZhukgHYouNLZy0wtNQJV+oItOByU9iKgNPnOL4tItc27x5njR4QSWwV95MdirJnZYN Ns1L27ESYZE1wwIa7DUV5APwo0PwGa/vytK0zIGi5TSHv5XO52zn1zxLk+mDleOCdR/M 0y/Av/LYhbYRiSzH/UvBsMW9lGUdfv32lktGOxGoVjioD7xHn27oN2/GZYW28lQbpOQN YMx2C1JQQmjTLgJ9GJC/SIg7LBiUfJsGrCXeWhRzlpCtSp/P5e2QnVKSMcyH6H+4Zmmg XR9w== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; t=1680093242; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=kpAhLQZY7Czy6y1NGq4c0NlbJ5rELrH1U8V8KvW/EPk=; b=SatV1Q26Lv1EeFFqqwx4GPzXFEd+qiEGIRzD0XqVlURurOgCzUhH6OZnQV2lzYlzQL Moy8qH+4A9ziBj3yMD65Mkef2ebW8IGNh/iYcHQkCKr35N4RWpraL0wyAHDsWeqW+Jq7 sX+fhWvlXg4ETOqG+tIREDNiB49thGx7Y4Vi5FyIaNUcaVM5oKIJUtcnyJ4OT/rJOAoA TNGRerPmdkDA8TKTJCKxSOD4JzGW4p234PXN79s6nM6qeQ8YmeOgMy2NpGzEB/yUtXDF KWpHpyajVTJQ2j3wtFKbVz3mvSj+Rh1lKtq6VejTnSY5V6bbruaNVVKHL04eJgIVHEvP ICnw== X-Gm-Message-State: AAQBX9fij+sNa/PQ2IPdgwh6uhacFIbi1HWy+T9EI0ukxj8cWbiT592E WlcGgtVxPBMbjSsnIMVVqwzy2WXNIMiEXUH9JnAYdnTeyhOrBYRU X-Google-Smtp-Source: AKy350bTEBVu80afZUAhcU2LzPQOG5P0SyVmTgeRpn2R04YwhKA3Js3ITRxqXFZvg3eiiSVvj8UFkqJHFHeBZUQEyHE= X-Received: by 2002:a63:c2:0:b0:513:5ac2:8e59 with SMTP id 185-20020a6300c2000000b005135ac28e59mr3176999pga.10.1680093242085; Wed, 29 Mar 2023 05:34:02 -0700 (PDT) MIME-Version: 1.0 References: <20230213100921.268770-1-jaz@semihalf.com> <20230213100921.268770-2-jaz@semihalf.com> In-Reply-To: <20230213100921.268770-2-jaz@semihalf.com> From: Grzegorz Jaszczyk Date: Wed, 29 Mar 2023 14:33:51 +0200 Message-ID: Subject: Re: [RFCv3 1/1] platform/x86: Add virtual PMC driver used for S2Idle To: linux-kernel@vger.kernel.org, hdegoede@redhat.com Cc: dmy@semihalf.com, tn@semihalf.com, dbehr@google.com, zide.chen@intel.corp-partner.google.com, seanjc@google.com, upstream@semihalf.com, markgross@kernel.org, dtor@google.com, mario.limonciello@amd.com, linux-pm@vger.kernel.org, x86@kernel.org, platform-driver-x86@vger.kernel.org, rafael@kernel.org Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org Hi Hans, Do you think that this RFC is in good enough state to start the ACPI ID registration process so after it will be completed we could land this solution? Or maybe we could land it (of course if there are no other remarks) even before and adjust if needed? Thank you in advance, Grzegorz pon., 13 lut 2023 o 11:11 Grzegorz Jaszczyk napisa=C5=82= (a): > > Virtual PMC driver is meant for the guest VMs for the S2Idle > notification. Its purpose is to register S2Idle dev ops check handler, > which will evaluate ACPI _DSM just before the guest enters S2Idle power > state. > > This allows to trap on MMIO access done as a consequence of _DSM > evaluation and therefore notify the VMM about the guest entering S2Idle > state. > > Signed-off-by: Grzegorz Jaszczyk > --- > Changelog v1..v2: > - Take advantage of acpi_s2idle_dev_ops's check() instead of notify() > > Changelog v2..v3: > - Add MODULE_LICENSE > - Remove "amd" prefixes > - Be more verbose in VIRT_PMC config description and make it > HYPERVISOR_GUEST dependent > - Add extra check ensuring that DSM method supports ACPI_VIRT_PMC_NOTIFY = function > --- > drivers/platform/x86/Kconfig | 7 +++ > drivers/platform/x86/Makefile | 3 ++ > drivers/platform/x86/virt_pmc.c | 83 +++++++++++++++++++++++++++++++++ > 3 files changed, 93 insertions(+) > create mode 100644 drivers/platform/x86/virt_pmc.c > > diff --git a/drivers/platform/x86/Kconfig b/drivers/platform/x86/Kconfig > index 5692385e2d26..837ce201b68b 100644 > --- a/drivers/platform/x86/Kconfig > +++ b/drivers/platform/x86/Kconfig > @@ -1099,6 +1099,13 @@ config WINMATE_FM07_KEYS > buttons below the display. This module adds an input device > that delivers key events when these buttons are pressed. > > +config VIRT_PMC > + tristate "Virtual Power Management Controller" > + depends on ACPI && SUSPEND && HYPERVISOR_GUEST > + help > + The Virtual PMC driver is meant for the guest VMs and its main > + purpose is to notify about guest entering s2idle state. > + > endif # X86_PLATFORM_DEVICES > > config P2SB > diff --git a/drivers/platform/x86/Makefile b/drivers/platform/x86/Makefil= e > index 1d3d1b02541b..c4d3056cf4ea 100644 > --- a/drivers/platform/x86/Makefile > +++ b/drivers/platform/x86/Makefile > @@ -129,6 +129,9 @@ obj-$(CONFIG_INTEL_SCU_WDT) +=3D intel_scu_wd= t.o > obj-$(CONFIG_INTEL_SCU_IPC_UTIL) +=3D intel_scu_ipcutil.o > obj-$(CONFIG_X86_INTEL_LPSS) +=3D pmc_atom.o > > +# Virtual PMC > +obj-$(CONFIG_VIRT_PMC) +=3D virt_pmc.o > + > # Siemens Simatic Industrial PCs > obj-$(CONFIG_SIEMENS_SIMATIC_IPC) +=3D simatic-ipc.o > > diff --git a/drivers/platform/x86/virt_pmc.c b/drivers/platform/x86/virt_= pmc.c > new file mode 100644 > index 000000000000..a5966bb9048f > --- /dev/null > +++ b/drivers/platform/x86/virt_pmc.c > @@ -0,0 +1,83 @@ > +// SPDX-License-Identifier: GPL-2.0-only > +/* > + * Virtual Power Management Controller Driver > + * > + * Author: Grzegorz Jaszczyk > + */ > + > +#include > +#include > + > +#define ACPI_VIRT_PMC_DSM_UUID "9ea49ba3-434a-49a6-be30-37cc55c4d397" > +#define ACPI_VIRT_PMC_NOTIFY 1 > + > +static acpi_handle virt_pmc_handle; > + > +static void virt_pmc_s2idle_notify(void) > +{ > + union acpi_object *out_obj; > + guid_t dsm_guid; > + > + guid_parse(ACPI_VIRT_PMC_DSM_UUID, &dsm_guid); > + > + out_obj =3D acpi_evaluate_dsm(virt_pmc_handle, &dsm_guid, > + 0, ACPI_VIRT_PMC_NOTIFY, NULL); > + > + acpi_handle_debug(virt_pmc_handle, "_DSM function %u evaluation %= s\n", > + ACPI_VIRT_PMC_NOTIFY, out_obj ? "successful" : = "failed"); > + > + ACPI_FREE(out_obj); > +} > + > +static struct acpi_s2idle_dev_ops pmc_s2idle_dev_ops =3D { > + .check =3D virt_pmc_s2idle_notify, > +}; > + > +static int virt_pmc_probe(struct platform_device *pdev) > +{ > + int err =3D 0; > + guid_t dsm_guid; > + > + virt_pmc_handle =3D ACPI_HANDLE(&pdev->dev); > + > + guid_parse(ACPI_VIRT_PMC_DSM_UUID, &dsm_guid); > + > + if (!acpi_check_dsm(virt_pmc_handle, &dsm_guid, 0, > + 1 << ACPI_VIRT_PMC_NOTIFY)) { > + dev_err(&pdev->dev, "DSM method doesn't support ACPI_VIRT= _PMC_NOTIFY\n"); > + return -ENODEV; > + } > + > + err =3D acpi_register_lps0_dev(&pmc_s2idle_dev_ops); > + if (err) > + dev_err(&pdev->dev, "failed to register LPS0 sleep handle= r\n"); > + > + return err; > +} > + > +static int virt_pmc_remove(struct platform_device *pdev) > +{ > + acpi_unregister_lps0_dev(&pmc_s2idle_dev_ops); > + > + return 0; > +} > + > +static const struct acpi_device_id virt_pmc_acpi_ids[] =3D { > + {"HYPE0001", 0}, /* _HID for XXX Power Engine, _CID PNP0D80*/ > + { } > +}; > +MODULE_DEVICE_TABLE(acpi, virt_pmc_acpi_ids); > + > +static struct platform_driver virt_pmc_driver =3D { > + .driver =3D { > + .name =3D "virtual_pmc", > + .acpi_match_table =3D ACPI_PTR(virt_pmc_acpi_ids), > + }, > + .probe =3D virt_pmc_probe, > + .remove =3D virt_pmc_remove, > +}; > + > +module_platform_driver(virt_pmc_driver); > + > +MODULE_LICENSE("GPL"); > +MODULE_DESCRIPTION("Virtual PMC Driver"); > -- > 2.39.1.581.gbfd45094c4-goog >