From patchwork Wed Aug 21 15:36:54 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steven Price X-Patchwork-Id: 11107367 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 62B241813 for ; Wed, 21 Aug 2019 15:37:34 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4962E23407 for ; Wed, 21 Aug 2019 15:37:34 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730189AbfHUPhd (ORCPT ); Wed, 21 Aug 2019 11:37:33 -0400 Received: from foss.arm.com ([217.140.110.172]:60478 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730183AbfHUPhc (ORCPT ); Wed, 21 Aug 2019 11:37:32 -0400 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 7168C1576; Wed, 21 Aug 2019 08:37:31 -0700 (PDT) Received: from e112269-lin.arm.com (e112269-lin.cambridge.arm.com [10.1.196.133]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id 6E6223F718; Wed, 21 Aug 2019 08:37:29 -0700 (PDT) From: Steven Price To: Marc Zyngier , Will Deacon , linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu Cc: Steven Price , Catalin Marinas , Paolo Bonzini , =?utf-8?b?UmFkaW0gS3LEjW3DocWZ?= , Russell King , James Morse , Julien Thierry , Suzuki K Pouloze , Mark Rutland , kvm@vger.kernel.org, linux-doc@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [PATCH v3 08/10] arm/arm64: Provide a wrapper for SMCCC 1.1 calls Date: Wed, 21 Aug 2019 16:36:54 +0100 Message-Id: <20190821153656.33429-9-steven.price@arm.com> X-Mailer: git-send-email 2.20.1 In-Reply-To: <20190821153656.33429-1-steven.price@arm.com> References: <20190821153656.33429-1-steven.price@arm.com> MIME-Version: 1.0 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org SMCCC 1.1 calls may use either HVC or SMC depending on the PSCI conduit. Rather than coding this in every call site provide a macro which uses the correct instruction. The macro also handles the case where no PSCI conduit is configured returning a not supported error in res, along with returning the conduit used for the call. This allow us to remove some duplicated code and will be useful later when adding paravirtualized time hypervisor calls. Signed-off-by: Steven Price Acked-by: Will Deacon --- include/linux/arm-smccc.h | 44 +++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+) diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index e7f129f26ebd..eee1e832221d 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -303,6 +303,50 @@ asmlinkage void __arm_smccc_hvc(unsigned long a0, unsigned long a1, #define SMCCC_RET_NOT_SUPPORTED -1 #define SMCCC_RET_NOT_REQUIRED -2 +/* Like arm_smccc_1_1* but always returns SMCCC_RET_NOT_SUPPORTED. + * Used when the PSCI conduit is not defined. The empty asm statement + * avoids compiler warnings about unused variables. + */ +#define __fail_smccc_1_1(...) \ + do { \ + __declare_args(__count_args(__VA_ARGS__), __VA_ARGS__); \ + asm ("" __constraints(__count_args(__VA_ARGS__))); \ + if (___res) \ + ___res->a0 = SMCCC_RET_NOT_SUPPORTED; \ + } while (0) + +/* + * arm_smccc_1_1_invoke() - make an SMCCC v1.1 compliant call + * + * This is a variadic macro taking one to eight source arguments, and + * an optional return structure. + * + * @a0-a7: arguments passed in registers 0 to 7 + * @res: result values from registers 0 to 3 + * + * This macro will make either an HVC call or an SMC call depending on the + * current PSCI conduit. If no valid conduit is available then -1 + * (SMCCC_RET_NOT_SUPPORTED) is returned in @res.a0 (if supplied). + * + * The return value also provides the conduit that was used. + */ +#define arm_smccc_1_1_invoke(...) ({ \ + int method = psci_ops.conduit; \ + switch (method) { \ + case PSCI_CONDUIT_HVC: \ + arm_smccc_1_1_hvc(__VA_ARGS__); \ + break; \ + case PSCI_CONDUIT_SMC: \ + arm_smccc_1_1_smc(__VA_ARGS__); \ + break; \ + default: \ + __fail_smccc_1_1(__VA_ARGS__); \ + method = PSCI_CONDUIT_NONE; \ + break; \ + } \ + method; \ + }) + /* Paravirtualised time calls (defined by ARM DEN0057A) */ #define ARM_SMCCC_HV_PV_FEATURES \ ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \