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 X-Spam-Level: X-Spam-Status: No, score=-12.8 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 A7609C4363D for ; Sat, 3 Oct 2020 08:56:18 +0000 (UTC) Received: from mm01.cs.columbia.edu (mm01.cs.columbia.edu [128.59.11.253]) by mail.kernel.org (Postfix) with ESMTP id 0B2CC206CA for ; Sat, 3 Oct 2020 08:56:17 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="kBpryh8U" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 0B2CC206CA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvmarm-bounces@lists.cs.columbia.edu Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id 6BF194B505; Sat, 3 Oct 2020 04:56:17 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Authentication-Results: mm01.cs.columbia.edu (amavisd-new); dkim=softfail (fail, message has been altered) header.i=@kernel.org Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Wmfz5L7IlPH7; Sat, 3 Oct 2020 04:56:15 -0400 (EDT) Received: from mm01.cs.columbia.edu (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id CD6D04B430; Sat, 3 Oct 2020 04:56:15 -0400 (EDT) Received: from localhost (localhost [127.0.0.1]) by mm01.cs.columbia.edu (Postfix) with ESMTP id D14BB4B430 for ; Sat, 3 Oct 2020 04:56:14 -0400 (EDT) X-Virus-Scanned: at lists.cs.columbia.edu Received: from mm01.cs.columbia.edu ([127.0.0.1]) by localhost (mm01.cs.columbia.edu [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id QtsOVqvGoinp for ; Sat, 3 Oct 2020 04:56:13 -0400 (EDT) Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by mm01.cs.columbia.edu (Postfix) with ESMTPS id 703694B419 for ; Sat, 3 Oct 2020 04:56:13 -0400 (EDT) Received: from e123331-lin.nice.arm.com (lfbn-nic-1-188-42.w2-15.abo.wanadoo.fr [2.15.37.42]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id B84FF206CA; Sat, 3 Oct 2020 08:56:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601715372; bh=6PQ9UY1YgWi3N2h59/B1+5v+PNePVQTT8d1MuxDMU/g=; h=From:To:Cc:Subject:Date:From; b=kBpryh8UYlKBkW5laC45wAmh8YpE5M5B7PmWj0i8aGEDKSc3jY5g6nH++Psizqsat RluYE+Fkg+L3PiKlZlJWgVxE31e1+w4+t7gt9/ANeTlJ3975RdWiJRmKxrT1HBtnCk UyplCVNe2Naa35Y3+U6hYyTxnIRG4IL3o3E9+cz0= From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] KVM: arm64: implement the TRNG hypervisor call Date: Sat, 3 Oct 2020 10:56:04 +0200 Message-Id: <20201003085604.7138-1-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 Cc: Lorenzo Pieralisi , Marc Zyngier , Sudeep Holla , Laszlo Ersek , Ard Biesheuvel , Andre Przywara , Catalin Marinas , Sami Mujawar , Leif Lindholm , Will Deacon , kvmarm@lists.cs.columbia.edu X-BeenThere: kvmarm@lists.cs.columbia.edu X-Mailman-Version: 2.1.14 Precedence: list List-Id: Where KVM/ARM decisions are made List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Errors-To: kvmarm-bounces@lists.cs.columbia.edu Sender: kvmarm-bounces@lists.cs.columbia.edu Provide a hypervisor implementation of the ARM architected TRNG firmware interface described in ARM spec DEN0098. All function IDs are implemented, including both 32-bit and 64-bit versions of the TRNG_RND service, which is the centerpiece of the API. The API is backed by arch_get_random_seed_long(), which is implemented in terms of RNDR currently, and will be alternatively backed by a SMC call to the secure firmware using same interface after a future patch. If neither are available, the kernel's entropy pool is used instead. Cc: Marc Zyngier Cc: James Morse Cc: Julien Thierry Cc: Suzuki K Poulose Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Lorenzo Pieralisi Cc: Sudeep Holla Cc: Sami Mujawar Cc: Andre Przywara Cc: Alexandru Elisei Cc: Laszlo Ersek Cc: Leif Lindholm Signed-off-by: Ard Biesheuvel --- arch/arm64/include/asm/kvm_host.h | 2 + arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/hypercalls.c | 6 ++ arch/arm64/kvm/trng.c | 91 ++++++++++++++++++++ include/linux/arm-smccc.h | 31 +++++++ 5 files changed, 131 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 65568b23868a..f76164d390ea 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -688,4 +688,6 @@ bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu); #define kvm_arm_vcpu_sve_finalized(vcpu) \ ((vcpu)->arch.flags & KVM_ARM64_VCPU_SVE_FINALIZED) +int kvm_trng_call(struct kvm_vcpu *vcpu); + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 99977c1972cc..e117d7086500 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -16,7 +16,7 @@ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ inject_fault.o regmap.o va_layout.o hyp.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ - aarch32.o arch_timer.o \ + aarch32.o arch_timer.o trng.o \ vgic/vgic.o vgic/vgic-init.o \ vgic/vgic-irqfd.o vgic/vgic-v2.o \ vgic/vgic-v3.o vgic/vgic-v4.o \ diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 550dfa3e53cd..70c5e815907d 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -62,6 +62,12 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) if (gpa != GPA_INVALID) val = gpa; break; + case ARM_SMCCC_TRNG_VERSION: + case ARM_SMCCC_TRNG_FEATURES: + case ARM_SMCCC_TRNG_GET_UUID: + case ARM_SMCCC_TRNG_RND: + case ARM_SMCCC_TRNG_RND64: + return kvm_trng_call(vcpu); default: return kvm_psci_call(vcpu); } diff --git a/arch/arm64/kvm/trng.c b/arch/arm64/kvm/trng.c new file mode 100644 index 000000000000..71f704075e4a --- /dev/null +++ b/arch/arm64/kvm/trng.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 Arm Ltd. + +#include +#include + +#include + +#include + +#define ARM_SMCCC_TRNG_VERSION_1_0 0x10000UL + +#define TRNG_SUCCESS 0UL +#define TRNG_NOT_SUPPORTED ((unsigned long)-1) +#define TRNG_INVALID_PARAMETER ((unsigned long)-2) +#define TRNG_NO_ENTROPY ((unsigned long)-3) + +#define MAX_BITS32 96 +#define MAX_BITS64 192 + +static const uuid_t arm_smc_trng_uuid __aligned(4) = UUID_INIT( + 0x023534a2, 0xe0bc, 0x45ec, 0x95, 0xdd, 0x33, 0x34, 0xc1, 0xcc, 0x31, 0x89); + +static int kvm_trng_do_rnd(struct kvm_vcpu *vcpu, int size) +{ + u32 num_bits = smccc_get_arg1(vcpu); + u64 bits[3]; + int i; + + if (num_bits > 3 * size) { + smccc_set_retval(vcpu, TRNG_NOT_SUPPORTED, 0, 0, 0); + return 1; + } + + /* get as many bits as we need to fulfil the request */ + for (i = 0; i < DIV_ROUND_UP(num_bits, 64); i++) + /* use the arm64 specific backend directly if one exists */ + if (!arch_get_random_seed_long((unsigned long *)&bits[i])) + bits[i] = get_random_long(); + + if (num_bits % 64) + bits[i - 1] &= U64_MAX >> (64 - (num_bits % 64)); + + while (i < ARRAY_SIZE(bits)) + bits[i++] = 0; + + if (size == 32) + smccc_set_retval(vcpu, TRNG_SUCCESS, lower_32_bits(bits[1]), + upper_32_bits(bits[0]), lower_32_bits(bits[0])); + else + smccc_set_retval(vcpu, TRNG_SUCCESS, bits[2], bits[1], bits[0]); + + memzero_explicit(bits, sizeof(bits)); + return 1; +} + +int kvm_trng_call(struct kvm_vcpu *vcpu) +{ + const __be32 *u = (__be32 *)arm_smc_trng_uuid.b; + u32 func_id = smccc_get_function(vcpu); + unsigned long val = TRNG_NOT_SUPPORTED; + int size = 64; + + switch (func_id) { + case ARM_SMCCC_TRNG_VERSION: + val = ARM_SMCCC_TRNG_VERSION_1_0; + break; + case ARM_SMCCC_TRNG_FEATURES: + switch (smccc_get_arg1(vcpu)) { + case ARM_SMCCC_TRNG_VERSION: + case ARM_SMCCC_TRNG_FEATURES: + case ARM_SMCCC_TRNG_GET_UUID: + case ARM_SMCCC_TRNG_RND: + case ARM_SMCCC_TRNG_RND64: + val = TRNG_SUCCESS; + } + break; + case ARM_SMCCC_TRNG_GET_UUID: + smccc_set_retval(vcpu, be32_to_cpu(u[3]), be32_to_cpu(u[2]), + be32_to_cpu(u[1]), be32_to_cpu(u[0])); + return 1; + case ARM_SMCCC_TRNG_RND: + size = 32; + fallthrough; + case ARM_SMCCC_TRNG_RND64: + return kvm_trng_do_rnd(vcpu, size); + } + + smccc_set_retval(vcpu, val, 0, 0, 0); + return 1; +} diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index 15c706fb0a37..9c9decd329b7 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -99,6 +99,37 @@ ARM_SMCCC_OWNER_STANDARD_HYP, \ 0x21) +/* TRNG entropy source calls (defined by ARM DEN0098) */ +#define ARM_SMCCC_TRNG_VERSION \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x50) + +#define ARM_SMCCC_TRNG_FEATURES \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x51) + +#define ARM_SMCCC_TRNG_GET_UUID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x52) + +#define ARM_SMCCC_TRNG_RND \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x53) + +#define ARM_SMCCC_TRNG_RND64 \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x53) + /* * Return codes defined in ARM DEN 0070A * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C -- 2.17.1 _______________________________________________ kvmarm mailing list kvmarm@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/kvmarm 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 X-Spam-Level: X-Spam-Status: No, score=-13.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, 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 ECDE9C4363D for ; 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Sat, 3 Oct 2020 08:56:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1601715372; bh=6PQ9UY1YgWi3N2h59/B1+5v+PNePVQTT8d1MuxDMU/g=; h=From:To:Cc:Subject:Date:From; b=kBpryh8UYlKBkW5laC45wAmh8YpE5M5B7PmWj0i8aGEDKSc3jY5g6nH++Psizqsat RluYE+Fkg+L3PiKlZlJWgVxE31e1+w4+t7gt9/ANeTlJ3975RdWiJRmKxrT1HBtnCk UyplCVNe2Naa35Y3+U6hYyTxnIRG4IL3o3E9+cz0= From: Ard Biesheuvel To: linux-arm-kernel@lists.infradead.org Subject: [PATCH] KVM: arm64: implement the TRNG hypervisor call Date: Sat, 3 Oct 2020 10:56:04 +0200 Message-Id: <20201003085604.7138-1-ardb@kernel.org> X-Mailer: git-send-email 2.17.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20201003_045613_420428_0E4D11B5 X-CRM114-Status: GOOD ( 23.63 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , Lorenzo Pieralisi , Suzuki K Poulose , Marc Zyngier , Sudeep Holla , Alexandru Elisei , Laszlo Ersek , Ard Biesheuvel , Andre Przywara , James Morse , Catalin Marinas , Sami Mujawar , Leif Lindholm , Will Deacon , kvmarm@lists.cs.columbia.edu, Julien Thierry MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org Provide a hypervisor implementation of the ARM architected TRNG firmware interface described in ARM spec DEN0098. All function IDs are implemented, including both 32-bit and 64-bit versions of the TRNG_RND service, which is the centerpiece of the API. The API is backed by arch_get_random_seed_long(), which is implemented in terms of RNDR currently, and will be alternatively backed by a SMC call to the secure firmware using same interface after a future patch. If neither are available, the kernel's entropy pool is used instead. Cc: Marc Zyngier Cc: James Morse Cc: Julien Thierry Cc: Suzuki K Poulose Cc: Catalin Marinas Cc: Will Deacon Cc: Mark Rutland Cc: Lorenzo Pieralisi Cc: Sudeep Holla Cc: Sami Mujawar Cc: Andre Przywara Cc: Alexandru Elisei Cc: Laszlo Ersek Cc: Leif Lindholm Signed-off-by: Ard Biesheuvel --- arch/arm64/include/asm/kvm_host.h | 2 + arch/arm64/kvm/Makefile | 2 +- arch/arm64/kvm/hypercalls.c | 6 ++ arch/arm64/kvm/trng.c | 91 ++++++++++++++++++++ include/linux/arm-smccc.h | 31 +++++++ 5 files changed, 131 insertions(+), 1 deletion(-) diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h index 65568b23868a..f76164d390ea 100644 --- a/arch/arm64/include/asm/kvm_host.h +++ b/arch/arm64/include/asm/kvm_host.h @@ -688,4 +688,6 @@ bool kvm_arm_vcpu_is_finalized(struct kvm_vcpu *vcpu); #define kvm_arm_vcpu_sve_finalized(vcpu) \ ((vcpu)->arch.flags & KVM_ARM64_VCPU_SVE_FINALIZED) +int kvm_trng_call(struct kvm_vcpu *vcpu); + #endif /* __ARM64_KVM_HOST_H__ */ diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile index 99977c1972cc..e117d7086500 100644 --- a/arch/arm64/kvm/Makefile +++ b/arch/arm64/kvm/Makefile @@ -16,7 +16,7 @@ kvm-y := $(KVM)/kvm_main.o $(KVM)/coalesced_mmio.o $(KVM)/eventfd.o \ inject_fault.o regmap.o va_layout.o hyp.o handle_exit.o \ guest.o debug.o reset.o sys_regs.o \ vgic-sys-reg-v3.o fpsimd.o pmu.o \ - aarch32.o arch_timer.o \ + aarch32.o arch_timer.o trng.o \ vgic/vgic.o vgic/vgic-init.o \ vgic/vgic-irqfd.o vgic/vgic-v2.o \ vgic/vgic-v3.o vgic/vgic-v4.o \ diff --git a/arch/arm64/kvm/hypercalls.c b/arch/arm64/kvm/hypercalls.c index 550dfa3e53cd..70c5e815907d 100644 --- a/arch/arm64/kvm/hypercalls.c +++ b/arch/arm64/kvm/hypercalls.c @@ -62,6 +62,12 @@ int kvm_hvc_call_handler(struct kvm_vcpu *vcpu) if (gpa != GPA_INVALID) val = gpa; break; + case ARM_SMCCC_TRNG_VERSION: + case ARM_SMCCC_TRNG_FEATURES: + case ARM_SMCCC_TRNG_GET_UUID: + case ARM_SMCCC_TRNG_RND: + case ARM_SMCCC_TRNG_RND64: + return kvm_trng_call(vcpu); default: return kvm_psci_call(vcpu); } diff --git a/arch/arm64/kvm/trng.c b/arch/arm64/kvm/trng.c new file mode 100644 index 000000000000..71f704075e4a --- /dev/null +++ b/arch/arm64/kvm/trng.c @@ -0,0 +1,91 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 Arm Ltd. + +#include +#include + +#include + +#include + +#define ARM_SMCCC_TRNG_VERSION_1_0 0x10000UL + +#define TRNG_SUCCESS 0UL +#define TRNG_NOT_SUPPORTED ((unsigned long)-1) +#define TRNG_INVALID_PARAMETER ((unsigned long)-2) +#define TRNG_NO_ENTROPY ((unsigned long)-3) + +#define MAX_BITS32 96 +#define MAX_BITS64 192 + +static const uuid_t arm_smc_trng_uuid __aligned(4) = UUID_INIT( + 0x023534a2, 0xe0bc, 0x45ec, 0x95, 0xdd, 0x33, 0x34, 0xc1, 0xcc, 0x31, 0x89); + +static int kvm_trng_do_rnd(struct kvm_vcpu *vcpu, int size) +{ + u32 num_bits = smccc_get_arg1(vcpu); + u64 bits[3]; + int i; + + if (num_bits > 3 * size) { + smccc_set_retval(vcpu, TRNG_NOT_SUPPORTED, 0, 0, 0); + return 1; + } + + /* get as many bits as we need to fulfil the request */ + for (i = 0; i < DIV_ROUND_UP(num_bits, 64); i++) + /* use the arm64 specific backend directly if one exists */ + if (!arch_get_random_seed_long((unsigned long *)&bits[i])) + bits[i] = get_random_long(); + + if (num_bits % 64) + bits[i - 1] &= U64_MAX >> (64 - (num_bits % 64)); + + while (i < ARRAY_SIZE(bits)) + bits[i++] = 0; + + if (size == 32) + smccc_set_retval(vcpu, TRNG_SUCCESS, lower_32_bits(bits[1]), + upper_32_bits(bits[0]), lower_32_bits(bits[0])); + else + smccc_set_retval(vcpu, TRNG_SUCCESS, bits[2], bits[1], bits[0]); + + memzero_explicit(bits, sizeof(bits)); + return 1; +} + +int kvm_trng_call(struct kvm_vcpu *vcpu) +{ + const __be32 *u = (__be32 *)arm_smc_trng_uuid.b; + u32 func_id = smccc_get_function(vcpu); + unsigned long val = TRNG_NOT_SUPPORTED; + int size = 64; + + switch (func_id) { + case ARM_SMCCC_TRNG_VERSION: + val = ARM_SMCCC_TRNG_VERSION_1_0; + break; + case ARM_SMCCC_TRNG_FEATURES: + switch (smccc_get_arg1(vcpu)) { + case ARM_SMCCC_TRNG_VERSION: + case ARM_SMCCC_TRNG_FEATURES: + case ARM_SMCCC_TRNG_GET_UUID: + case ARM_SMCCC_TRNG_RND: + case ARM_SMCCC_TRNG_RND64: + val = TRNG_SUCCESS; + } + break; + case ARM_SMCCC_TRNG_GET_UUID: + smccc_set_retval(vcpu, be32_to_cpu(u[3]), be32_to_cpu(u[2]), + be32_to_cpu(u[1]), be32_to_cpu(u[0])); + return 1; + case ARM_SMCCC_TRNG_RND: + size = 32; + fallthrough; + case ARM_SMCCC_TRNG_RND64: + return kvm_trng_do_rnd(vcpu, size); + } + + smccc_set_retval(vcpu, val, 0, 0, 0); + return 1; +} diff --git a/include/linux/arm-smccc.h b/include/linux/arm-smccc.h index 15c706fb0a37..9c9decd329b7 100644 --- a/include/linux/arm-smccc.h +++ b/include/linux/arm-smccc.h @@ -99,6 +99,37 @@ ARM_SMCCC_OWNER_STANDARD_HYP, \ 0x21) +/* TRNG entropy source calls (defined by ARM DEN0098) */ +#define ARM_SMCCC_TRNG_VERSION \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x50) + +#define ARM_SMCCC_TRNG_FEATURES \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x51) + +#define ARM_SMCCC_TRNG_GET_UUID \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x52) + +#define ARM_SMCCC_TRNG_RND \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x53) + +#define ARM_SMCCC_TRNG_RND64 \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, \ + ARM_SMCCC_SMC_64, \ + ARM_SMCCC_OWNER_STANDARD, \ + 0x53) + /* * Return codes defined in ARM DEN 0070A * ARM DEN 0070A is now merged/consolidated into ARM DEN 0028 C -- 2.17.1 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel