From patchwork Mon Jul 8 15:44:38 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13726757 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 24741C3DA42 for ; Mon, 8 Jul 2024 15:46:58 +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=s7jekH0xBYmVRzLByHRNneAZeTjxZwDOC5hT7+Jd+Ag=; b=eiun9tr7+/Ttc+ykOnCmx85jGV o7vG3uiY9ninZrSmETQR84wmn6ptncFNFIT3Owm1fSBN8GrxUdFHx08lMY8HY8AouJ8adaqWAmvJr lqIP7O8v2HRcUZnyiu7r6Dk7Jnl+VSvkHVenN1VFoet2+d2c+6M+aQzxTNnjmJ1yQvICBgQajt/sj QxoHbyh022AbmCvqIhp14AqGEHAS8WGZu4xiU3m5sbxCx/0L6Ibs/xYL7cLgRioaXFci81Kw/B9IE 6moxZPWjvomcBDtbC5PIVAf/9xmpD1jebah4pm5rRheDgsRpwjNZ9iaZsMw7z/NWEa6YW6X+VBdEu YFhKKkWw==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQqZj-00000004HUq-2Rsl; Mon, 08 Jul 2024 15:46:47 +0000 Received: from dfw.source.kernel.org ([139.178.84.217]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sQqXy-00000004Gi7-3TDV for linux-arm-kernel@lists.infradead.org; Mon, 08 Jul 2024 15:45:00 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by dfw.source.kernel.org (Postfix) with ESMTP id E808E60F0B; Mon, 8 Jul 2024 15:44:55 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B358FC4AF11; Mon, 8 Jul 2024 15:44:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1720453495; bh=Uv0z9ntISDWqUONsGZqFUTjAheaQ1E1mlpLqi6+ng6M=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vRyoxTCQSNWbyMYEHSAdVp0bBfgm63kTrCTK4sKrZ7D1jt0sYg0AieQ968QNw9AyI J+/A4sLDMwriiaD/2MtU2sRGwj3uwSoGx25+4XdiihXQ8evspg2dOCf6ymS6PFi6bu k4/4p6OgE1KwtIVLCZpBg6WEXnoZ7bzi43aGf0aV1LTRtyIRdpWKVr5ZJqnXCGBiSm gyNtclQmEtfCPchp6aAw5Ydlpt1KOIGfPl5m4kgyEM2eCfvtbTNf/E2uz3gL7U6Xmr 0kKBejlDN8pZpvqW1Jbtu3WdI0r+HpZJcTOuNjYYn8zsf85U30ohPXjLAzfBLuZbSm nvPaGr0BT/CSw== Received: from sofa.misterjones.org ([185.219.108.64] helo=valley-girl.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.95) (envelope-from ) id 1sQqXt-00Ae1P-Ua; Mon, 08 Jul 2024 16:44:54 +0100 From: Marc Zyngier To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org Cc: James Morse , Suzuki K Poulose , Oliver Upton , Zenghui Yu , Fuad Tabba , Joey Gouly , Mark Brown Subject: [PATCH 7/7] KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guests Date: Mon, 8 Jul 2024 16:44:38 +0100 Message-Id: <20240708154438.1218186-8-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240708154438.1218186-1-maz@kernel.org> References: <20240708154438.1218186-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 185.219.108.64 X-SA-Exim-Rcpt-To: kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org, kvm@vger.kernel.org, james.morse@arm.com, suzuki.poulose@arm.com, oliver.upton@linux.dev, yuzenghui@huawei.com, tabba@google.com, joey.gouly@arm.com, broonie@kernel.org X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20240708_084458_958442_ABE0B5E2 X-CRM114-Status: GOOD ( 13.03 ) 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 Everything is now in place for a guest to "enjoy" FP8 support. Expose ID_AA64PFR2_EL1 to both userspace and guests, with the explicit restriction of only being able to clear FPMR. All other features (MTE* at the time of writing) are hidden and not writable. Signed-off-by: Marc Zyngier --- arch/arm64/kvm/sys_regs.c | 16 +++++++++++++++- 1 file changed, 15 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kvm/sys_regs.c b/arch/arm64/kvm/sys_regs.c index 8b5caad651512..e6f9e380283ea 100644 --- a/arch/arm64/kvm/sys_regs.c +++ b/arch/arm64/kvm/sys_regs.c @@ -1722,6 +1722,15 @@ static u64 read_sanitised_id_aa64pfr0_el1(struct kvm_vcpu *vcpu, return val; } +static u64 read_sanitised_id_aa64pfr2_el1(struct kvm_vcpu *vcpu, + const struct sys_reg_desc *rd) +{ + u64 val = read_sanitised_ftr_reg(SYS_ID_AA64PFR2_EL1); + + /* We only expose FPMR */ + return val & ID_AA64PFR2_EL1_FPMR; +} + #define ID_REG_LIMIT_FIELD_ENUM(val, reg, field, limit) \ ({ \ u64 __f_val = FIELD_GET(reg##_##field##_MASK, val); \ @@ -2381,7 +2390,12 @@ static const struct sys_reg_desc sys_reg_descs[] = { ID_AA64PFR0_EL1_AdvSIMD | ID_AA64PFR0_EL1_FP), }, ID_SANITISED(ID_AA64PFR1_EL1), - ID_UNALLOCATED(4,2), + { SYS_DESC(SYS_ID_AA64PFR2_EL1), + .access = access_id_reg, + .get_user = get_id_reg, + .set_user = set_id_reg, + .reset = read_sanitised_id_aa64pfr2_el1, + .val = ID_AA64PFR2_EL1_FPMR, }, ID_UNALLOCATED(4,3), ID_WRITABLE(ID_AA64ZFR0_EL1, ~ID_AA64ZFR0_EL1_RES0), ID_HIDDEN(ID_AA64SMFR0_EL1),