From patchwork Tue Aug 13 10:44:00 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 13761774 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 95C85C52D7C for ; Tue, 13 Aug 2024 10:49:46 +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=xDp/D6NcQ+Mq7D+u7jIQqj/DHKa6AlReLHbL/SO8lgM=; b=MITG6nKccEU823PovQwl5UULUl Gh3TQHV41NooN/Xj8ziktr1mD2yzVXwpTWapRZNlzTJkeeSvfPqGZRylg1GNAWkkMgTxQHY31T9zh P29ko1iyP7hbkxWARja05Hyj3vJiPX2lkl2MkDrDBa6oMZWrJnvGd8QcmMBIniU8/r44ZEXf/9nir whnqGh+yskpB9685ESLKijGENfqGknZX1jjXS621brtXK4jzsg9vas+U2KEuB2rzm25IXIbjy4Heo N0fZkGKS7p5nQVAUDlMb/ibSMtlxR/LFeilIw2UGOP2ISOM182NkOU/Q80dTZmM7/smY7/Q+gtT4m if/YFDMA==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdp5r-00000003OZC-3bhk; Tue, 13 Aug 2024 10:49:35 +0000 Received: from sin.source.kernel.org ([145.40.73.55]) by bombadil.infradead.org with esmtps (Exim 4.97.1 #2 (Red Hat Linux)) id 1sdp0g-00000003NGF-1hrq for linux-arm-kernel@lists.infradead.org; Tue, 13 Aug 2024 10:44:16 +0000 Received: from smtp.kernel.org (transwarp.subspace.kernel.org [100.75.92.58]) by sin.source.kernel.org (Postfix) with ESMTP id 4D396CE12A1; Tue, 13 Aug 2024 10:44:12 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3CB21C4AF15; Tue, 13 Aug 2024 10:44:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1723545851; bh=Xu/A5wRo87cCV/14kvsmL7JZiq2gS7qhR9OHy9H2AHg=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=uWG6gU2zu+S/dmU9/enI3mJ6kre1VSoect6wCQCTt067yL/3m5rGPh0TPk1kd6Gs4 irvs3eoKYyjufG+LYdWO1SzEzVgWdf+ceZKeH5OMNo6bTqxYR8Z3999e2P4Mp+g2vT L5W3z0FT/XP1c2QKmzd+Ng1AbJ9c3YcJalV+hT7bkMA9lEDnwkvzIPMbXXj/5P/eFP LPqPeJyy0LZy9a+aljbANIMnNpRRtwU1606hAk4BfODSAOAbbZaM5/ulcdtzTRmroi 4wuPDzoZsx1D+Mj4Fo6tv7nUBLfdhswDMG7I42sUWSyIizi5xSHITywoYTc9kozsWa y56NeyK5R6DCA== 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 1sdp0b-003JD1-GB; Tue, 13 Aug 2024 11:44:09 +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 v3 8/8] KVM: arm64: Expose ID_AA64PFR2_EL1 to userspace and guests Date: Tue, 13 Aug 2024 11:44:00 +0100 Message-Id: <20240813104400.1956132-9-maz@kernel.org> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20240813104400.1956132-1-maz@kernel.org> References: <20240813104400.1956132-1-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-20240813_034414_701554_1C257309 X-CRM114-Status: GOOD ( 12.95 ) 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 51627add0a72..da6d017f24a1 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),