From patchwork Tue Oct 31 15:51:04 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Dave Martin X-Patchwork-Id: 832619 Return-Path: X-Original-To: incoming-imx@patchwork.ozlabs.org Delivered-To: patchwork-incoming-imx@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=lists.infradead.org (client-ip=65.50.211.133; helo=bombadil.infradead.org; envelope-from=linux-arm-kernel-bounces+incoming-imx=patchwork.ozlabs.org@lists.infradead.org; receiver=) Authentication-Results: ozlabs.org; dkim=pass (2048-bit key; unprotected) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="uimIt2uh"; dkim-atps=neutral Received: from bombadil.infradead.org (bombadil.infradead.org [65.50.211.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ozlabs.org (Postfix) with ESMTPS id 3yRGPq1Kn9z9sPs for ; Wed, 1 Nov 2017 03:04:31 +1100 (AEDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:To:From:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=iUHYWjQVJ3s9H6pMG196DSM0D5INkU8CvJgYw7pr6sA=; b=uimIt2uhMNKQ/P hrNiR03iTpvMcaeqVLG5gNc0IammDmTyWeoG+2r6FL1r/MGJHHN8TRTGZxgpM7JImf7M3yeZqWgnn pwhCNfBzWc1m0wq1wbkwlBzNjaGj42T5r/vjVbgZUT88Tar2syRBNp+2OMsiIPUBFOGj8BQtHE3t6 cY+gw6PNJkymeWUZj4q7TO5zq9EZvyz6v+n4YWVi/CXZq7VeUlRyi3M/22zEp/BhjIbW0Emv0KxNT z0TEjAr5Gdjba9/8hX05bx9MZU9uaeQkq+5ZjLR+F6rhUYoK7DGiaXBPOoNFBFJPjXf/G562Nyydc 8+mwHMgvRb8xwdQI+4ZA==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1e9Z1h-00077q-2X; Tue, 31 Oct 2017 16:04:29 +0000 Received: from foss.arm.com ([217.140.101.70]) by bombadil.infradead.org with esmtp (Exim 4.87 #1 (Red Hat Linux)) id 1e9Ypr-00043A-Mc for linux-arm-kernel@lists.infradead.org; Tue, 31 Oct 2017 15:52:21 +0000 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.72.51.249]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 1796F15AD; Tue, 31 Oct 2017 08:51:55 -0700 (PDT) Received: from e103592.cambridge.arm.com (usa-sjc-imap-foss1.foss.arm.com [10.72.51.249]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 396D43F24A; Tue, 31 Oct 2017 08:51:53 -0700 (PDT) From: Dave Martin To: linux-arm-kernel@lists.infradead.org Subject: [PATCH v5 12/30] arm64/sve: Low-level CPU setup Date: Tue, 31 Oct 2017 15:51:04 +0000 Message-Id: <1509465082-30427-13-git-send-email-Dave.Martin@arm.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1509465082-30427-1-git-send-email-Dave.Martin@arm.com> References: <1509465082-30427-1-git-send-email-Dave.Martin@arm.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20171031_085215_755907_CD3427B3 X-CRM114-Status: UNSURE ( 8.90 ) X-CRM114-Notice: Please train this message. X-Spam-Score: -6.9 (------) X-Spam-Report: SpamAssassin version 3.4.1 on bombadil.infradead.org summary: Content analysis details: (-6.9 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at http://www.dnswl.org/, high trust [217.140.101.70 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record -0.0 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -1.9 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-arch@vger.kernel.org, Okamoto Takayuki , libc-alpha@sourceware.org, Ard Biesheuvel , Szabolcs Nagy , Catalin Marinas , Will Deacon , =?utf-8?q?Alex_Benn=C3=A9e?= , kvmarm@lists.cs.columbia.edu Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+incoming-imx=patchwork.ozlabs.org@lists.infradead.org List-Id: linux-imx-kernel.lists.patchwork.ozlabs.org To enable the kernel to use SVE, SVE traps from EL1 to EL2 must be disabled. To take maximum advantage of the hardware, the full available vector length also needs to be enabled for EL1 by programming ZCR_EL2.LEN. (The kernel will program ZCR_EL1.LEN as required, but this cannot override the limit set by ZCR_EL2.) This patch makes the appropriate changes to the EL2 early setup code. Signed-off-by: Dave Martin Reviewed-by: Catalin Marinas Cc: Alex Bennée Reviewed-by: Alex Bennée --- **Dropped at v3** Reviewed-by: Alex Bennée (Due to significant changes to the logic.) --- arch/arm64/kernel/head.S | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/arm64/kernel/head.S b/arch/arm64/kernel/head.S index cfa90a4..67e86a0 100644 --- a/arch/arm64/kernel/head.S +++ b/arch/arm64/kernel/head.S @@ -524,8 +524,19 @@ CPU_LE( movk x0, #0x30d0, lsl #16 ) // Clear EE and E0E on LE systems mov x0, #0x33ff msr cptr_el2, x0 // Disable copro. traps to EL2 + /* SVE register access */ + mrs x1, id_aa64pfr0_el1 + ubfx x1, x1, #ID_AA64PFR0_SVE_SHIFT, #4 + cbz x1, 7f + + bic x0, x0, #CPTR_EL2_TZ // Also disable SVE traps + msr cptr_el2, x0 // Disable copro. traps to EL2 + isb + mov x1, #ZCR_ELx_LEN_MASK // SVE: Enable full vector + msr_s SYS_ZCR_EL2, x1 // length for EL1. + /* Hypervisor stub */ - adr_l x0, __hyp_stub_vectors +7: adr_l x0, __hyp_stub_vectors msr vbar_el2, x0 /* spsr */