From patchwork Tue Feb 2 14:11:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Marc Zyngier X-Patchwork-Id: 12061859 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-17.0 required=3.0 tests=BAYES_00,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C1A4EC433E0 for ; Tue, 2 Feb 2021 14:32:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9239264F4D for ; Tue, 2 Feb 2021 14:32:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234538AbhBBOcq (ORCPT ); Tue, 2 Feb 2021 09:32:46 -0500 Received: from mail.kernel.org ([198.145.29.99]:52232 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232072AbhBBOTQ (ORCPT ); Tue, 2 Feb 2021 09:19:16 -0500 Received: from disco-boy.misterjones.org (disco-boy.misterjones.org [51.254.78.96]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 771FF64E27; Tue, 2 Feb 2021 14:12:11 +0000 (UTC) Received: from 78.163-31-62.static.virginmediabusiness.co.uk ([62.31.163.78] helo=why.lan) by disco-boy.misterjones.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94) (envelope-from ) id 1l6wPZ-00BVqw-Op; Tue, 02 Feb 2021 14:12:09 +0000 From: Marc Zyngier To: netdev@vger.kernel.org, yangbo.lu@nxp.com, john.stultz@linaro.org, tglx@linutronix.de, pbonzini@redhat.com, seanjc@google.com, richardcochran@gmail.com, Mark.Rutland@arm.com, will@kernel.org, suzuki.poulose@arm.com, Andre.Przywara@arm.com, steven.price@arm.com Cc: linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Steve.Capper@arm.com, justin.he@arm.com, jianyong.wu@arm.com, kernel-team@android.com Subject: [PATCH v17 1/7] arm/arm64: Probe for the presence of KVM hypervisor Date: Tue, 2 Feb 2021 14:11:58 +0000 Message-Id: <20210202141204.3134855-2-maz@kernel.org> X-Mailer: git-send-email 2.29.2 In-Reply-To: <20210202141204.3134855-1-maz@kernel.org> References: <20210202141204.3134855-1-maz@kernel.org> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 62.31.163.78 X-SA-Exim-Rcpt-To: netdev@vger.kernel.org, yangbo.lu@nxp.com, john.stultz@linaro.org, tglx@linutronix.de, pbonzini@redhat.com, seanjc@google.com, richardcochran@gmail.com, Mark.Rutland@arm.com, will@kernel.org, suzuki.poulose@arm.com, Andre.Przywara@arm.com, steven.price@arm.com, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.cs.columbia.edu, kvm@vger.kernel.org, Steve.Capper@arm.com, justin.he@arm.com, jianyong.wu@arm.com, kernel-team@android.com X-SA-Exim-Mail-From: maz@kernel.org X-SA-Exim-Scanned: No (on disco-boy.misterjones.org); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Will Deacon Although the SMCCC specification provides some limited functionality for describing the presence of hypervisor and firmware services, this is generally applicable only to functions designated as "Arm Architecture Service Functions" and no portable discovery mechanism is provided for standard hypervisor services, despite having a designated range of function identifiers reserved by the specification. In an attempt to avoid the need for additional firmware changes every time a new function is added, introduce a UID to identify the service provider as being compatible with KVM. Once this has been established, additional services can be discovered via a feature bitmap. Signed-off-by: Will Deacon Signed-off-by: Jianyong Wu [maz: move code to its own file, plug it into PSCI] Signed-off-by: Marc Zyngier Link: https://lore.kernel.org/r/20201209060932.212364-2-jianyong.wu@arm.com --- arch/arm/include/asm/hypervisor.h | 3 ++ arch/arm64/include/asm/hypervisor.h | 3 ++ drivers/firmware/psci/psci.c | 2 ++ drivers/firmware/smccc/Makefile | 2 +- drivers/firmware/smccc/kvm_guest.c | 51 +++++++++++++++++++++++++++++ drivers/firmware/smccc/smccc.c | 1 + include/linux/arm-smccc.h | 25 ++++++++++++++ 7 files changed, 86 insertions(+), 1 deletion(-) create mode 100644 drivers/firmware/smccc/kvm_guest.c diff --git a/arch/arm/include/asm/hypervisor.h b/arch/arm/include/asm/hypervisor.h index df8524365637..bd61502b9715 100644 --- a/arch/arm/include/asm/hypervisor.h +++ b/arch/arm/include/asm/hypervisor.h @@ -4,4 +4,7 @@ #include +void kvm_init_hyp_services(void); +bool kvm_arm_hyp_service_available(u32 func_id); + #endif diff --git a/arch/arm64/include/asm/hypervisor.h b/arch/arm64/include/asm/hypervisor.h index f9cc1d021791..0ae427f352c8 100644 --- a/arch/arm64/include/asm/hypervisor.h +++ b/arch/arm64/include/asm/hypervisor.h @@ -4,4 +4,7 @@ #include +void kvm_init_hyp_services(void); +bool kvm_arm_hyp_service_available(u32 func_id); + #endif diff --git a/drivers/firmware/psci/psci.c b/drivers/firmware/psci/psci.c index f5fc429cae3f..69e296f02902 100644 --- a/drivers/firmware/psci/psci.c +++ b/drivers/firmware/psci/psci.c @@ -23,6 +23,7 @@ #include #include +#include #include #include #include @@ -498,6 +499,7 @@ static int __init psci_probe(void) psci_init_cpu_suspend(); psci_init_system_suspend(); psci_init_system_reset2(); + kvm_init_hyp_services(); } return 0; diff --git a/drivers/firmware/smccc/Makefile b/drivers/firmware/smccc/Makefile index 72ab84042832..40d19144a860 100644 --- a/drivers/firmware/smccc/Makefile +++ b/drivers/firmware/smccc/Makefile @@ -1,4 +1,4 @@ # SPDX-License-Identifier: GPL-2.0 # -obj-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smccc.o +obj-$(CONFIG_HAVE_ARM_SMCCC_DISCOVERY) += smccc.o kvm_guest.o obj-$(CONFIG_ARM_SMCCC_SOC_ID) += soc_id.o diff --git a/drivers/firmware/smccc/kvm_guest.c b/drivers/firmware/smccc/kvm_guest.c new file mode 100644 index 000000000000..23ce1ded88b4 --- /dev/null +++ b/drivers/firmware/smccc/kvm_guest.c @@ -0,0 +1,51 @@ +// SPDX-License-Identifier: GPL-2.0 + +#define pr_fmt(fmt) "smccc: KVM: " fmt + +#include +#include +#include +#include + +static DECLARE_BITMAP(__kvm_arm_hyp_services, ARM_SMCCC_KVM_NUM_FUNCS) __ro_after_init = { }; + +void __init kvm_init_hyp_services(void) +{ + int i; + struct arm_smccc_res res; + + if (arm_smccc_1_1_get_conduit() != SMCCC_CONDUIT_HVC) + return; + + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, &res); + if (res.a0 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0 || + res.a1 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1 || + res.a2 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2 || + res.a3 != ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3) + return; + + memset(&res, 0, sizeof(res)); + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID, &res); + for (i = 0; i < 32; ++i) { + if (res.a0 & (i)) + set_bit(i + (32 * 0), __kvm_arm_hyp_services); + if (res.a1 & (i)) + set_bit(i + (32 * 1), __kvm_arm_hyp_services); + if (res.a2 & (i)) + set_bit(i + (32 * 2), __kvm_arm_hyp_services); + if (res.a3 & (i)) + set_bit(i + (32 * 3), __kvm_arm_hyp_services); + } + + pr_info("hypervisor services detected (0x%08lx 0x%08lx 0x%08lx 0x%08lx)\n", + res.a3, res.a2, res.a1, res.a0); +} + +bool kvm_arm_hyp_service_available(u32 func_id) +{ + if (func_id >= ARM_SMCCC_KVM_NUM_FUNCS) + return -EINVAL; + + return test_bit(func_id, __kvm_arm_hyp_services); +} +EXPORT_SYMBOL_GPL(kvm_arm_hyp_service_available); diff --git a/drivers/firmware/smccc/smccc.c b/drivers/firmware/smccc/smccc.c index 00c88b809c0c..94eca6ffda05 100644 --- a/drivers/firmware/smccc/smccc.c +++ b/drivers/firmware/smccc/smccc.c @@ -7,6 +7,7 @@ #include #include +#include static u32 smccc_version = ARM_SMCCC_VERSION_1_0; static enum arm_smccc_conduit smccc_conduit = SMCCC_CONDUIT_NONE; diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index f860645f6512..74e90b65b489 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -55,6 +55,8 @@ #define ARM_SMCCC_OWNER_TRUSTED_OS 50 #define ARM_SMCCC_OWNER_TRUSTED_OS_END 63 +#define ARM_SMCCC_FUNC_QUERY_CALL_UID 0xff01 + #define ARM_SMCCC_QUIRK_NONE 0 #define ARM_SMCCC_QUIRK_QCOM_A6 1 /* Save/restore register a6 */ @@ -87,6 +89,29 @@ ARM_SMCCC_SMC_32, \ 0, 0x7fff) +#define ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_FUNC_QUERY_CALL_UID) + +/* KVM UID value: 28b46fb6-2ec5-11e9-a9ca-4b564d003a74 */ +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_0 0xb66fb428U +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_1 0xe911c52eU +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_2 0x564bcaa9U +#define ARM_SMCCC_VENDOR_HYP_UID_KVM_REG_3 0x743a004dU + +/* KVM "vendor specific" services */ +#define ARM_SMCCC_KVM_FUNC_FEATURES 0 +#define ARM_SMCCC_KVM_FUNC_FEATURES_2 127 +#define ARM_SMCCC_KVM_NUM_FUNCS 128 + +#define ARM_SMCCC_VENDOR_HYP_KVM_FEATURES_FUNC_ID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_VENDOR_HYP, \ + ARM_SMCCC_KVM_FUNC_FEATURES) + #define SMCCC_ARCH_WORKAROUND_RET_UNAFFECTED 1 /* Paravirtualised time calls (defined by ARM DEN0057A) */