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 lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 5B27BFD3767 for ; Wed, 25 Feb 2026 15:20:39 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1vvGgQ-0007o6-Dw; Wed, 25 Feb 2026 10:20:14 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vvGgO-0007mp-Oo for qemu-devel@nongnu.org; Wed, 25 Feb 2026 10:20:12 -0500 Received: from us-smtp-delivery-124.mimecast.com ([170.10.129.124]) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1vvGgM-00031l-Q5 for qemu-devel@nongnu.org; Wed, 25 Feb 2026 10:20:12 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1772032809; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=Az+riaC/VH6n3RtnoJo1WZLfnynDIMNpzKr5EZ7PtZQ=; b=by1NsLbnyYkEbxExBQWElCJK1VLxO1vEJGhyGo+LBhOMJhwtKcLzVno1nwNNw2mFNcSDY1 J8YgcOGjT3VCde4TYG8KPQjrqHG+v059HTXWV4tmchhOW4Jg+JvoF42DfhJ021b1HL/kxJ C3spo933BXJu9cWIM8dkxMqxjoA8p/Y= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-613-XKdxygqOOG-mpLP8RBfMbA-1; Wed, 25 Feb 2026 10:20:05 -0500 X-MC-Unique: XKdxygqOOG-mpLP8RBfMbA-1 X-Mimecast-MFC-AGG-ID: XKdxygqOOG-mpLP8RBfMbA_1772032804 Received: from mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.17]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id BDCD51956057; Wed, 25 Feb 2026 15:20:03 +0000 (UTC) Received: from redhat.com (unknown [10.45.225.165]) by mx-prod-int-05.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 46B741955F43; Wed, 25 Feb 2026 15:20:00 +0000 (UTC) Date: Wed, 25 Feb 2026 15:19:56 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: Igor Mammedov Cc: Peter Maydell , qemu-devel@nongnu.org, mst@redhat.com, anisinha@redhat.com, pbonzini@redhat.com, shannon.zhaosl@gmail.com, philmd@linaro.org, zhao1.liu@intel.com, rad@semihalf.com, leif.lindholm@oss.qualcomm.com Subject: Re: [PATCH 08/11] arm: virt: create GWDT watchdog paired with WDAT ACPI table Message-ID: References: <20260206131438.1857182-1-imammedo@redhat.com> <20260206131438.1857182-9-imammedo@redhat.com> <20260219131751.4e4e4e0e@imammedo> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20260219131751.4e4e4e0e@imammedo> User-Agent: Mutt/2.2.14 (2025-02-20) X-Scanned-By: MIMEDefang 3.0 on 10.30.177.17 Received-SPF: pass client-ip=170.10.129.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -5 X-Spam_score: -0.6 X-Spam_bar: / X-Spam_report: (-0.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H4=0.001, RCVD_IN_MSPIKE_WL=0.001, RCVD_IN_VALIDITY_RPBL_BLOCKED=0.734, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.78, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001 autolearn=no autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org On Thu, Feb 19, 2026 at 01:17:51PM +0100, Igor Mammedov wrote: > On Wed, 18 Feb 2026 19:08:36 +0000 > Peter Maydell wrote: > > > On Fri, 6 Feb 2026 at 13:15, Igor Mammedov wrote: > > > > > > Add SBSA generic watchdog to virt machine type with > > > all necessary wiring for ACPI watchdog. Which includes > > > setting its frequency to 1KHz (max that WDAT is able to handle). > > > > > > Signed-off-by: Igor Mammedov > > > --- > > > > > diff --git a/hw/arm/virt.c b/hw/arm/virt.c > > > index 390845c503..caf5700ed2 100644 > > > --- a/hw/arm/virt.c > > > +++ b/hw/arm/virt.c > > > @@ -93,6 +93,7 @@ > > > #include "hw/cxl/cxl.h" > > > #include "hw/cxl/cxl_host.h" > > > #include "qemu/guest-random.h" > > > +#include "hw/watchdog/sbsa_gwdt.h" > > > > > > static GlobalProperty arm_virt_compat[] = { > > > { TYPE_VIRTIO_IOMMU_PCI, "aw-bits", "48" }, > > > @@ -194,6 +195,8 @@ static const MemMapEntry base_memmap[] = { > > > [VIRT_PVTIME] = { 0x090a0000, 0x00010000 }, > > > [VIRT_SECURE_GPIO] = { 0x090b0000, 0x00001000 }, > > > [VIRT_ACPI_PCIHP] = { 0x090c0000, ACPI_PCIHP_SIZE }, > > > + [VIRT_GWDT_REFRESH] = { 0x090d0000, 0x00001000 }, > > > + [VIRT_GWDT_CONTROL] = { 0x090d1000, 0x00001000 }, > > > [VIRT_MMIO] = { 0x0a000000, 0x00000200 }, > > > /* ...repeating for a total of NUM_VIRTIO_TRANSPORTS, each of that size */ > > > [VIRT_PLATFORM_BUS] = { 0x0c000000, 0x02000000 }, > > > @@ -245,12 +248,32 @@ static const int a15irqmap[] = { > > > [VIRT_GPIO] = 7, > > > [VIRT_UART1] = 8, > > > [VIRT_ACPI_GED] = 9, > > > + [VIRT_GWDT_WS0] = 10, > > > [VIRT_MMIO] = 16, /* ...to 16 + NUM_VIRTIO_TRANSPORTS - 1 */ > > > [VIRT_GIC_V2M] = 48, /* ...to 48 + NUM_GICV2M_SPIS - 1 */ > > > [VIRT_SMMU] = 74, /* ...to 74 + NUM_SMMU_IRQS - 1 */ > > > [VIRT_PLATFORM_BUS] = 112, /* ...to 112 + PLATFORM_BUS_NUM_IRQS -1 */ > > > }; > > > > > > +static void create_wdt(const VirtMachineState *vms) > > > +{ > > > + hwaddr rbase = vms->memmap[VIRT_GWDT_REFRESH].base; > > > + hwaddr cbase = vms->memmap[VIRT_GWDT_CONTROL].base; > > > + int irq = vms->irqmap[VIRT_GWDT_WS0]; > > > + DeviceState *dev = qdev_new(TYPE_WDT_SBSA); > > > + SysBusDevice *s = SYS_BUS_DEVICE(dev); > > > + > > > + /* > > > + * Set watchdog tick freq to 1Kz as it's the max WDAT driver > > > + * is able to handle. > > > + */ > > > + qdev_prop_set_uint64(dev, "clock-frequency", 1000 /* 1KHz */); > > > + sysbus_realize_and_unref(s, &error_fatal); > > > + sysbus_mmio_map(s, 0, rbase); > > > + sysbus_mmio_map(s, 1, cbase); > > > + sysbus_connect_irq(s, 0, qdev_get_gpio_in(vms->gic, irq)); > > > +} > > > > Please can you also add support for exposing this device > > in the device tree ? > > It's possible, > but we probably should not enable it if acpi variant was requested, > to avoid confusion on guest side. > > For Windows it doesn't really mater, for linux it does. > on x86 linux guest uses a quirk to disable native iTCO watchdog > in favor of WDAT one if later is present. > I assume quirk is not desirable so we should expose only a preferred > variant. > > > > > > + > > > static void create_randomness(MachineState *ms, const char *node) > > > { > > > struct { > > > @@ -2515,6 +2538,9 @@ static void machvirt_init(MachineState *machine) > > > vms->highmem_ecam &= (!firmware_loaded || aarch64); > > > > > > create_rtc(vms); > > > + if (machine->acpi_watchdog) { > > > + create_wdt(vms); > > > + } > > > > Can we have a command line option name that isn't ACPI > > specific, please? There's nothing inherent to ACPI about > > "I would like a watchdog device". > > that is specifically asking for ACPI flavor being used/configured. > acpi specific option conflates 2 things: > 1. watchdog device creation (of the board choice) with properties tuned for WDAT usage > 2. how to expose it on firmware level (in this case ACPI WDAT table) > > other option, I've considered was > -device some_wd[,fw=dt|acpi|none] > but then 'fw' is not exactly device property but rather a machine one > (we can 'abuse' it/use as a proxy of cause). > However it doesn't work for boards that have builtin watchdog. Right, if there was a case where we were already using -device to create the watchdog, then I would suggest having a simple 'wadt=on|off' property as standard for any watchdog wanting that ACPI abstraction wrapper. That could (hypothetically) be the case if we had chosen to add WADT suport backed by i6300esb, eg -device i6300esb,wadt=on|off For cases built-in to the machine type, I'd suggest -wadt=on|off eg for Q35, "-machine q35,itco-wadt=on|off" for virt, '-machine virt,gwdt-wadt=on|off' Q35 is easier as we rely on the guest quirks to disable direct access via both paths. With GWDT we need to decide if gwdt-wadt=on should imply DTB disabled, or if we just expose both & rely on a guest quirk or worst case, need a separate property to toggle DTB too. > I've used device property for x86 Q35 TCO watchdog and > then using -global to enable it as workaround in previous version. > Ugly but doable workaround. It puts a burden on users to learn how > to configure it for each support watchdog/board combo. > It's nightmare to discover/maintain though. > > Hence in this version, I've used a generic machine property approach > that exposes feature in uniform way across boards. > > enum might work, but ... > machine.watchdog = [acpi | what else could we put here???] > > I'm not married to a way how we expose/configure it and will rewrite > it to something that works for majority. > > > thanks > > -- PMM > > > With regards, Daniel -- |: https://berrange.com ~~ https://hachyderm.io/@berrange :| |: https://libvirt.org ~~ https://entangle-photo.org :| |: https://pixelfed.art/berrange ~~ https://fstop138.berrange.com :|