From mboxrd@z Thu Jan 1 00:00:00 1970 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 5870AC44536 for ; Tue, 21 Jul 2026 20:12:23 +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=pCGLDie0xV9RJpzuDsm4ooq0RYqsnGfSauPh4xAqSiU=; b=oMF91OW+Y+6TxJ3HGdg2bzaioY Ax3SdScARFDFyJrLYYUTxfbqRp7jdMv0WkNtryg9a+IwM4NuJ2Tqu6hoK87j3Wel9WrBCbS95DHK/ uHqHGqJiA6TFShkKiGITJbBZnBS/k2iGdSu2kc/YZ4js7JbwJMJhFsBzWpgIsHMdzrJzEHArX/i3W O7IC6Jl9Dbz229Vm5oW9ICtUGHJ3IkpeJcypc7fLf+rYFSUP885h2tGNke+lBAw+D+HL/19MEbtA4 3MAeTW4oIS66L8VVsCFKDIxccQEtd6PXuj9CusR3lsU/rmt06NBw1SmDF9omWJhQie8gTqbJWdD1p Y8iqKG7w==; Received: from localhost ([::1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmGp6-0000000ALgd-1o0O; Tue, 21 Jul 2026 20:12:16 +0000 Received: from linux.microsoft.com ([13.77.154.182]) by bombadil.infradead.org with esmtp (Exim 4.99.1 #2 (Red Hat Linux)) id 1wmGot-0000000ALa7-0zmO for linux-arm-kernel@lists.infradead.org; Tue, 21 Jul 2026 20:12:05 +0000 Received: from linuxonhyperv3.guj3yctzbm1etfxqx2vob5hsef.xx.internal.cloudapp.net (linux.microsoft.com [13.77.154.182]) by linux.microsoft.com (Postfix) with ESMTPSA id 1B9F820B716A; Tue, 21 Jul 2026 13:11:49 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com 1B9F820B716A DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1784664709; bh=pCGLDie0xV9RJpzuDsm4ooq0RYqsnGfSauPh4xAqSiU=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=hnpKnP6Z4zrW2K8tIRM/j8EXiwFFtaqRbEJ5pOheySz+xbkbBIul05cTGVe5go2XA 7xdZYAPC9iwhbq3aKXB9sWNeYId3epPSM+bg2ht7daHWf7z3LiYprPFf14finkHt+S iTOr/00eNxCYcZpfmagALucxS6gxwulldG1OPKyQ= From: Kameron Carr To: kys@microsoft.com, haiyangz@microsoft.com, wei.liu@kernel.org, decui@microsoft.com, longli@microsoft.com, mhklinux@outlook.com Cc: catalin.marinas@arm.com, will@kernel.org, mark.rutland@arm.com, lpieralisi@kernel.org, sudeep.holla@kernel.org, arnd@arndb.de, thuth@redhat.com, linux-hyperv@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org Subject: [PATCH v3 2/6] firmware: smccc: Detect hypervisor via RSI host call in CCA Realms Date: Tue, 21 Jul 2026 13:11:44 -0700 Message-ID: <20260721201148.1441143-3-kameroncarr@linux.microsoft.com> X-Mailer: git-send-email 2.43.7 In-Reply-To: <20260721201148.1441143-1-kameroncarr@linux.microsoft.com> References: <20260721201148.1441143-1-kameroncarr@linux.microsoft.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.9.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20260721_131203_609553_AEEEC0FC X-CRM114-Status: GOOD ( 13.34 ) 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 Modify arm_smccc_hypervisor_has_uuid() to check is_realm_world() and use rsi_host_call() to query the hypervisor vendor UUID when inside a Realm. The realm path is factored into a helper, arm_smccc_realm_get_hypervisor_uuid(), that owns a file-static rsi_host_call buffer (uuid_hc) serialized by a spinlock. The RSI-specific includes, file-static state and helper are guarded with CONFIG_ARM64 because does not exist on 32-bit ARM. For non-Realm environments, the existing arm_smccc_1_1_invoke() path is unchanged. Signed-off-by: Kameron Carr --- drivers/firmware/smccc/smccc.c | 41 +++++++++++++++++++++++++++++++++- 1 file changed, 40 insertions(+), 1 deletion(-) diff --git a/drivers/firmware/smccc/smccc.c b/drivers/firmware/smccc/smccc.c index bdee057db2fd3..a876b7aa2dc99 100644 --- a/drivers/firmware/smccc/smccc.c +++ b/drivers/firmware/smccc/smccc.c @@ -12,6 +12,12 @@ #include #include +#ifdef CONFIG_ARM64 +#include +#include +#include +#endif + static u32 smccc_version = ARM_SMCCC_VERSION_1_0; static enum arm_smccc_conduit smccc_conduit = SMCCC_CONDUIT_NONE; @@ -67,12 +73,45 @@ s32 arm_smccc_get_soc_id_revision(void) } EXPORT_SYMBOL_GPL(arm_smccc_get_soc_id_revision); +#ifdef CONFIG_ARM64 +static struct rsi_host_call uuid_hc; +static DEFINE_SPINLOCK(uuid_hc_lock); + +/* + * Helper function to get the hypervisor UUID via an RsiHostCall. + */ +static void arm_smccc_realm_get_hypervisor_uuid(struct arm_smccc_res *res) +{ + guard(spinlock_irqsave)(&uuid_hc_lock); + + memset(&uuid_hc, 0, sizeof(uuid_hc)); + uuid_hc.gprs[0] = ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID; + + if (rsi_host_call(__pa_symbol(&uuid_hc)) != RSI_SUCCESS) { + res->a0 = SMCCC_RET_NOT_SUPPORTED; + return; + } + + res->a0 = uuid_hc.gprs[0]; + res->a1 = uuid_hc.gprs[1]; + res->a2 = uuid_hc.gprs[2]; + res->a3 = uuid_hc.gprs[3]; +} +#endif + bool arm_smccc_hypervisor_has_uuid(const uuid_t *hyp_uuid) { struct arm_smccc_res res = {}; uuid_t uuid; - arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, &res); +#ifdef CONFIG_ARM64 + if (is_realm_world()) + arm_smccc_realm_get_hypervisor_uuid(&res); + else +#endif + arm_smccc_1_1_invoke(ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID, + &res); + if (res.a0 == SMCCC_RET_NOT_SUPPORTED) return false; -- 2.45.4