From patchwork Tue Dec 3 19:32:18 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Oliver Upton X-Patchwork-Id: 13892852 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 bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 277C6E74AC8 for ; Tue, 3 Dec 2024 19:46:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20210309; h=Sender:List-Subscribe:List-Help :List-Post:List-Archive:List-Unsubscribe:List-Id:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-Id:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:List-Owner; bh=GjObVzSUPGyiRyx8ZPD/sAgeVRJoiPetpoC5aOxqHj0=; b=X3rcKXOy9+BPt9g+HdPyBxzTS1 dF7PJwTqBsTP5nidMYU80S+x2FfbOv9WAT+xahXQVuaafiIZ9eDinSrgrQvj8b+9y2HwDIjdVYofs zfbijnFL5SVMRwka+SPDFEMymFqRytL/bFrpsWOFzvkW1Sja7j/SW+Y34GI6taMWDHhwBNnF4Kb5k tBfEesjimzZcYFK9sMIwuSojnvGVkkwO7C1dyBKwvYXUuu86eL++1ewWZLNg3Jw12JHu1fmiwrEKP 6VvTUKvnPSTacJUHtvk6NDn6St2p8f+/9ApMWYDnPkw6KpzY9AZEf4sqQsXh2dKuLFpx6ZpU/y07E 6PYni5yg==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.98 #2 (Red Hat Linux)) id 1tIYqT-0000000AWJz-2vQ7; Tue, 03 Dec 2024 19:46:05 +0000 Received: from out-172.mta1.migadu.com ([2001:41d0:203:375::ac]) by bombadil.infradead.org with esmtps (Exim 4.98 #2 (Red Hat Linux)) id 1tIYeH-0000000AU76-1CoI for linux-arm-kernel@lists.infradead.org; Tue, 03 Dec 2024 19:33:30 +0000 X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1733254406; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=GjObVzSUPGyiRyx8ZPD/sAgeVRJoiPetpoC5aOxqHj0=; b=cJXK4INL5jtoZAsVKaT4wMa0IFT2vyHXw/V60yqBYaCbLzzagsQo2oxhgaGZBMFaxdA7xO uTM//NBSf6MXu/swHUQrOPQ3U0GI4KKCT/QYoSi7B97s9ihPnJVkaXM8HKQgP0edrmEz9a 6fyyV66ig91+6AszbHOSrlwLio0eemo= From: Oliver Upton To: kvmarm@lists.linux.dev Cc: Marc Zyngier , Joey Gouly , Suzuki K Poulose , Zenghui Yu , Mingwei Zhang , Colton Lewis , Raghavendra Rao Ananta , Catalin Marinas , Will Deacon , Mark Rutland , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, Oliver Upton Subject: [RFC PATCH 12/14] KVM: arm64: Advertise PMUv3 if IMPDEF traps are present Date: Tue, 3 Dec 2024 11:32:18 -0800 Message-Id: <20241203193220.1070811-13-oliver.upton@linux.dev> In-Reply-To: <20241203193220.1070811-1-oliver.upton@linux.dev> References: <20241203193220.1070811-1-oliver.upton@linux.dev> MIME-Version: 1.0 X-Migadu-Flow: FLOW_OUT X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20241203_113329_464622_51FC1255 X-CRM114-Status: GOOD ( 10.82 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Advertise a baseline PMUv3 implementation when running on hardware with IMPDEF traps of the PMUv3 sysregs. Signed-off-by: Oliver Upton --- arch/arm64/kvm/pmu-emul.c | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/pmu-emul.c b/arch/arm64/kvm/pmu-emul.c index 8a565817a814..34d9c08af209 100644 --- a/arch/arm64/kvm/pmu-emul.c +++ b/arch/arm64/kvm/pmu-emul.c @@ -1260,7 +1260,17 @@ u8 kvm_arm_pmu_get_pmuver_limit(void) pmuver = SYS_FIELD_GET(ID_AA64DFR0_EL1, PMUVer, read_sanitised_ftr_reg(SYS_ID_AA64DFR0_EL1)); - /* Treat IMPLEMENTATION DEFINED functionality as unimplemented */ + /* + * Spoof a barebones PMUv3 implementation if the system supports IMPDEF + * traps of the PMUv3 sysregs + */ + if (cpus_have_final_cap(ARM64_WORKAROUND_PMUV3_IMPDEF_TRAPS)) + return ID_AA64DFR0_EL1_PMUVer_IMP; + + /* + * Otherwise, treat IMPLEMENTATION DEFINED functionality as + * unimplemented + */ if (pmuver == ID_AA64DFR0_EL1_PMUVer_IMP_DEF) return 0;