From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anup Patel Date: Fri, 20 Oct 2023 12:51:35 +0530 Subject: [PATCH v3 4/9] RISC-V: KVM: Forward SBI DBCN extension to user-space In-Reply-To: <20231020072140.900967-1-apatel@ventanamicro.com> References: <20231020072140.900967-1-apatel@ventanamicro.com> Message-ID: <20231020072140.900967-5-apatel@ventanamicro.com> List-Id: To: kvm-riscv@lists.infradead.org MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit The frozen SBI v2.0 specification defines the SBI debug console (DBCN) extension which replaces the legacy SBI v0.1 console functions namely sbi_console_getchar() and sbi_console_putchar(). The SBI DBCN extension needs to be emulated in the KVM user-space (i.e. QEMU-KVM or KVMTOOL) so we forward SBI DBCN calls from KVM guest to the KVM user-space which can then redirect the console input/output to wherever it wants (e.g. telnet, file, stdio, etc). The SBI debug console is simply a early console available to KVM guest for early prints and it does not intend to replace the proper console devices such as 8250, VirtIO console, etc. Signed-off-by: Anup Patel Reviewed-by: Andrew Jones --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 1 + arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/vcpu_sbi.c | 4 ++++ arch/riscv/kvm/vcpu_sbi_replace.c | 32 +++++++++++++++++++++++++++ 4 files changed, 38 insertions(+) diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index c02bda5559d7..6a453f7f8b56 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -73,6 +73,7 @@ extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm; +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor; diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 917d8cc2489e..60d3b21dead7 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -156,6 +156,7 @@ enum KVM_RISCV_SBI_EXT_ID { KVM_RISCV_SBI_EXT_PMU, KVM_RISCV_SBI_EXT_EXPERIMENTAL, KVM_RISCV_SBI_EXT_VENDOR, + KVM_RISCV_SBI_EXT_DBCN, KVM_RISCV_SBI_EXT_MAX, }; diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index bda8b0b33343..a04ff98085d9 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -66,6 +66,10 @@ static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = { .ext_idx = KVM_RISCV_SBI_EXT_PMU, .ext_ptr = &vcpu_sbi_ext_pmu, }, + { + .ext_idx = KVM_RISCV_SBI_EXT_DBCN, + .ext_ptr = &vcpu_sbi_ext_dbcn, + }, { .ext_idx = KVM_RISCV_SBI_EXT_EXPERIMENTAL, .ext_ptr = &vcpu_sbi_ext_experimental, diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 7c4d5d38a339..23b57c931b15 100644 --- a/arch/riscv/kvm/vcpu_sbi_replace.c +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -175,3 +175,35 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst = { .extid_end = SBI_EXT_SRST, .handler = kvm_sbi_ext_srst_handler, }; + +static int kvm_sbi_ext_dbcn_handler(struct kvm_vcpu *vcpu, + struct kvm_run *run, + struct kvm_vcpu_sbi_return *retdata) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long funcid = cp->a6; + + switch (funcid) { + case SBI_EXT_DBCN_CONSOLE_WRITE: + case SBI_EXT_DBCN_CONSOLE_READ: + case SBI_EXT_DBCN_CONSOLE_WRITE_BYTE: + /* + * The SBI debug console functions are unconditionally + * forwarded to the userspace. + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + retdata->uexit = true; + break; + default: + retdata->err_val = SBI_ERR_NOT_SUPPORTED; + } + + return 0; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn = { + .extid_start = SBI_EXT_DBCN, + .extid_end = SBI_EXT_DBCN, + .default_unavail = true, + .handler = kvm_sbi_ext_dbcn_handler, +}; -- 2.34.1 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 4C214C004C0 for ; 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Fri, 20 Oct 2023 00:22:07 -0700 (PDT) From: Anup Patel To: Paolo Bonzini , Atish Patra , Palmer Dabbelt , Paul Walmsley , Greg Kroah-Hartman , Jiri Slaby Cc: Conor Dooley , Andrew Jones , kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-serial@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Anup Patel Subject: [PATCH v3 4/9] RISC-V: KVM: Forward SBI DBCN extension to user-space Date: Fri, 20 Oct 2023 12:51:35 +0530 Message-Id: <20231020072140.900967-5-apatel@ventanamicro.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231020072140.900967-1-apatel@ventanamicro.com> References: <20231020072140.900967-1-apatel@ventanamicro.com> MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20231020_002210_388570_A7377BCB X-CRM114-Status: GOOD ( 13.85 ) X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-riscv" Errors-To: linux-riscv-bounces+linux-riscv=archiver.kernel.org@lists.infradead.org The frozen SBI v2.0 specification defines the SBI debug console (DBCN) extension which replaces the legacy SBI v0.1 console functions namely sbi_console_getchar() and sbi_console_putchar(). The SBI DBCN extension needs to be emulated in the KVM user-space (i.e. QEMU-KVM or KVMTOOL) so we forward SBI DBCN calls from KVM guest to the KVM user-space which can then redirect the console input/output to wherever it wants (e.g. telnet, file, stdio, etc). The SBI debug console is simply a early console available to KVM guest for early prints and it does not intend to replace the proper console devices such as 8250, VirtIO console, etc. Signed-off-by: Anup Patel Reviewed-by: Andrew Jones --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 1 + arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/vcpu_sbi.c | 4 ++++ arch/riscv/kvm/vcpu_sbi_replace.c | 32 +++++++++++++++++++++++++++ 4 files changed, 38 insertions(+) diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index c02bda5559d7..6a453f7f8b56 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -73,6 +73,7 @@ extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm; +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor; diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 917d8cc2489e..60d3b21dead7 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -156,6 +156,7 @@ enum KVM_RISCV_SBI_EXT_ID { KVM_RISCV_SBI_EXT_PMU, KVM_RISCV_SBI_EXT_EXPERIMENTAL, KVM_RISCV_SBI_EXT_VENDOR, + KVM_RISCV_SBI_EXT_DBCN, KVM_RISCV_SBI_EXT_MAX, }; diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index bda8b0b33343..a04ff98085d9 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -66,6 +66,10 @@ static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = { .ext_idx = KVM_RISCV_SBI_EXT_PMU, .ext_ptr = &vcpu_sbi_ext_pmu, }, + { + .ext_idx = KVM_RISCV_SBI_EXT_DBCN, + .ext_ptr = &vcpu_sbi_ext_dbcn, + }, { .ext_idx = KVM_RISCV_SBI_EXT_EXPERIMENTAL, .ext_ptr = &vcpu_sbi_ext_experimental, diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 7c4d5d38a339..23b57c931b15 100644 --- a/arch/riscv/kvm/vcpu_sbi_replace.c +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -175,3 +175,35 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst = { .extid_end = SBI_EXT_SRST, .handler = kvm_sbi_ext_srst_handler, }; + +static int kvm_sbi_ext_dbcn_handler(struct kvm_vcpu *vcpu, + struct kvm_run *run, + struct kvm_vcpu_sbi_return *retdata) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long funcid = cp->a6; + + switch (funcid) { + case SBI_EXT_DBCN_CONSOLE_WRITE: + case SBI_EXT_DBCN_CONSOLE_READ: + case SBI_EXT_DBCN_CONSOLE_WRITE_BYTE: + /* + * The SBI debug console functions are unconditionally + * forwarded to the userspace. + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + retdata->uexit = true; + break; + default: + retdata->err_val = SBI_ERR_NOT_SUPPORTED; + } + + return 0; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn = { + .extid_start = SBI_EXT_DBCN, + .extid_end = SBI_EXT_DBCN, + .default_unavail = true, + .handler = kvm_sbi_ext_dbcn_handler, +}; -- 2.34.1 _______________________________________________ linux-riscv mailing list linux-riscv@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-riscv 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id E9450C07480 for ; 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Fri, 20 Oct 2023 00:22:08 -0700 (PDT) Received: from anup-ubuntu-vm.localdomain ([171.76.83.81]) by smtp.gmail.com with ESMTPSA id v12-20020a63f20c000000b005b32d6b4f2fsm828204pgh.81.2023.10.20.00.22.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Oct 2023 00:22:07 -0700 (PDT) From: Anup Patel To: Paolo Bonzini , Atish Patra , Palmer Dabbelt , Paul Walmsley , Greg Kroah-Hartman , Jiri Slaby Cc: Conor Dooley , Andrew Jones , kvm@vger.kernel.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-serial@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-kernel@vger.kernel.org, Anup Patel Subject: [PATCH v3 4/9] RISC-V: KVM: Forward SBI DBCN extension to user-space Date: Fri, 20 Oct 2023 12:51:35 +0530 Message-Id: <20231020072140.900967-5-apatel@ventanamicro.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231020072140.900967-1-apatel@ventanamicro.com> References: <20231020072140.900967-1-apatel@ventanamicro.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-serial@vger.kernel.org The frozen SBI v2.0 specification defines the SBI debug console (DBCN) extension which replaces the legacy SBI v0.1 console functions namely sbi_console_getchar() and sbi_console_putchar(). The SBI DBCN extension needs to be emulated in the KVM user-space (i.e. QEMU-KVM or KVMTOOL) so we forward SBI DBCN calls from KVM guest to the KVM user-space which can then redirect the console input/output to wherever it wants (e.g. telnet, file, stdio, etc). The SBI debug console is simply a early console available to KVM guest for early prints and it does not intend to replace the proper console devices such as 8250, VirtIO console, etc. Signed-off-by: Anup Patel Reviewed-by: Andrew Jones --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 1 + arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/vcpu_sbi.c | 4 ++++ arch/riscv/kvm/vcpu_sbi_replace.c | 32 +++++++++++++++++++++++++++ 4 files changed, 38 insertions(+) diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index c02bda5559d7..6a453f7f8b56 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -73,6 +73,7 @@ extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm; +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor; diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 917d8cc2489e..60d3b21dead7 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -156,6 +156,7 @@ enum KVM_RISCV_SBI_EXT_ID { KVM_RISCV_SBI_EXT_PMU, KVM_RISCV_SBI_EXT_EXPERIMENTAL, KVM_RISCV_SBI_EXT_VENDOR, + KVM_RISCV_SBI_EXT_DBCN, KVM_RISCV_SBI_EXT_MAX, }; diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index bda8b0b33343..a04ff98085d9 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -66,6 +66,10 @@ static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = { .ext_idx = KVM_RISCV_SBI_EXT_PMU, .ext_ptr = &vcpu_sbi_ext_pmu, }, + { + .ext_idx = KVM_RISCV_SBI_EXT_DBCN, + .ext_ptr = &vcpu_sbi_ext_dbcn, + }, { .ext_idx = KVM_RISCV_SBI_EXT_EXPERIMENTAL, .ext_ptr = &vcpu_sbi_ext_experimental, diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 7c4d5d38a339..23b57c931b15 100644 --- a/arch/riscv/kvm/vcpu_sbi_replace.c +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -175,3 +175,35 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst = { .extid_end = SBI_EXT_SRST, .handler = kvm_sbi_ext_srst_handler, }; + +static int kvm_sbi_ext_dbcn_handler(struct kvm_vcpu *vcpu, + struct kvm_run *run, + struct kvm_vcpu_sbi_return *retdata) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long funcid = cp->a6; + + switch (funcid) { + case SBI_EXT_DBCN_CONSOLE_WRITE: + case SBI_EXT_DBCN_CONSOLE_READ: + case SBI_EXT_DBCN_CONSOLE_WRITE_BYTE: + /* + * The SBI debug console functions are unconditionally + * forwarded to the userspace. + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + retdata->uexit = true; + break; + default: + retdata->err_val = SBI_ERR_NOT_SUPPORTED; + } + + return 0; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn = { + .extid_start = SBI_EXT_DBCN, + .extid_end = SBI_EXT_DBCN, + .default_unavail = true, + .handler = kvm_sbi_ext_dbcn_handler, +}; -- 2.34.1 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (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 576A4CDB47E for ; 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bh=hO8QQxSKIIq22xFRYvu7Gu8eaqjv2hPcSOTMD/z9e94=; b=QZ54szb9gcD6Hhrp3Vbwaaw+DpoKS1v6uUJJ96+425TFz4UtIxM/PTy7EpZTB8I5ps SW/19Owq9sHhmZC7BA++tYOi7GssYFHRAvVpXN1J7hQw6SkMpIZ/2F1BckmPxb9n+WxE Bucm9khyPErZIn9l5uxFIsNxxipmGAHnMsmRP5KYp4FPH0Pl3t9L8ouk8upzlwWjzW26 k0CUNfU/IVsM8PPFQBeGW6Qp5s0dEwLfzBHRqW2LIsK00hHe3Hyx7PmCN7v8VZT6ZIHF x5QbpFKYo+UP6dwptfLiTIY2/2Iyqw/7DYKdoh0LohCppJWm0L0bbv6MvqSKjuvkzced hTpw== X-Gm-Message-State: AOJu0Yze+HSCQSszYHv/5IxHCBltLENinfz73MFMVXbHF0edJsn4c9XH k+klupZO+KKrKr6VFM0shm59Sg== X-Google-Smtp-Source: AGHT+IEkj9caZAnNIJ+YKQHJFuBSd9R4KVCbXPxdNGw5YMPQO4SC5tQtDdGdQxSt48V7VnxE9x8JkQ== X-Received: by 2002:aa7:9622:0:b0:68e:42c9:74e0 with SMTP id r2-20020aa79622000000b0068e42c974e0mr952140pfg.3.1697786528093; Fri, 20 Oct 2023 00:22:08 -0700 (PDT) Received: from anup-ubuntu-vm.localdomain ([171.76.83.81]) by smtp.gmail.com with ESMTPSA id v12-20020a63f20c000000b005b32d6b4f2fsm828204pgh.81.2023.10.20.00.22.03 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 20 Oct 2023 00:22:07 -0700 (PDT) From: Anup Patel To: Paolo Bonzini , Atish Patra , Palmer Dabbelt , Paul Walmsley , Greg Kroah-Hartman , Jiri Slaby Subject: [PATCH v3 4/9] RISC-V: KVM: Forward SBI DBCN extension to user-space Date: Fri, 20 Oct 2023 12:51:35 +0530 Message-Id: <20231020072140.900967-5-apatel@ventanamicro.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20231020072140.900967-1-apatel@ventanamicro.com> References: <20231020072140.900967-1-apatel@ventanamicro.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Anup Patel , linux-serial@vger.kernel.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Conor Dooley , kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linuxppc-dev@lists.ozlabs.org, Andrew Jones Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" The frozen SBI v2.0 specification defines the SBI debug console (DBCN) extension which replaces the legacy SBI v0.1 console functions namely sbi_console_getchar() and sbi_console_putchar(). The SBI DBCN extension needs to be emulated in the KVM user-space (i.e. QEMU-KVM or KVMTOOL) so we forward SBI DBCN calls from KVM guest to the KVM user-space which can then redirect the console input/output to wherever it wants (e.g. telnet, file, stdio, etc). The SBI debug console is simply a early console available to KVM guest for early prints and it does not intend to replace the proper console devices such as 8250, VirtIO console, etc. Signed-off-by: Anup Patel Reviewed-by: Andrew Jones --- arch/riscv/include/asm/kvm_vcpu_sbi.h | 1 + arch/riscv/include/uapi/asm/kvm.h | 1 + arch/riscv/kvm/vcpu_sbi.c | 4 ++++ arch/riscv/kvm/vcpu_sbi_replace.c | 32 +++++++++++++++++++++++++++ 4 files changed, 38 insertions(+) diff --git a/arch/riscv/include/asm/kvm_vcpu_sbi.h b/arch/riscv/include/asm/kvm_vcpu_sbi.h index c02bda5559d7..6a453f7f8b56 100644 --- a/arch/riscv/include/asm/kvm_vcpu_sbi.h +++ b/arch/riscv/include/asm/kvm_vcpu_sbi.h @@ -73,6 +73,7 @@ extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_ipi; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_rfence; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_hsm; +extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_experimental; extern const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_vendor; diff --git a/arch/riscv/include/uapi/asm/kvm.h b/arch/riscv/include/uapi/asm/kvm.h index 917d8cc2489e..60d3b21dead7 100644 --- a/arch/riscv/include/uapi/asm/kvm.h +++ b/arch/riscv/include/uapi/asm/kvm.h @@ -156,6 +156,7 @@ enum KVM_RISCV_SBI_EXT_ID { KVM_RISCV_SBI_EXT_PMU, KVM_RISCV_SBI_EXT_EXPERIMENTAL, KVM_RISCV_SBI_EXT_VENDOR, + KVM_RISCV_SBI_EXT_DBCN, KVM_RISCV_SBI_EXT_MAX, }; diff --git a/arch/riscv/kvm/vcpu_sbi.c b/arch/riscv/kvm/vcpu_sbi.c index bda8b0b33343..a04ff98085d9 100644 --- a/arch/riscv/kvm/vcpu_sbi.c +++ b/arch/riscv/kvm/vcpu_sbi.c @@ -66,6 +66,10 @@ static const struct kvm_riscv_sbi_extension_entry sbi_ext[] = { .ext_idx = KVM_RISCV_SBI_EXT_PMU, .ext_ptr = &vcpu_sbi_ext_pmu, }, + { + .ext_idx = KVM_RISCV_SBI_EXT_DBCN, + .ext_ptr = &vcpu_sbi_ext_dbcn, + }, { .ext_idx = KVM_RISCV_SBI_EXT_EXPERIMENTAL, .ext_ptr = &vcpu_sbi_ext_experimental, diff --git a/arch/riscv/kvm/vcpu_sbi_replace.c b/arch/riscv/kvm/vcpu_sbi_replace.c index 7c4d5d38a339..23b57c931b15 100644 --- a/arch/riscv/kvm/vcpu_sbi_replace.c +++ b/arch/riscv/kvm/vcpu_sbi_replace.c @@ -175,3 +175,35 @@ const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_srst = { .extid_end = SBI_EXT_SRST, .handler = kvm_sbi_ext_srst_handler, }; + +static int kvm_sbi_ext_dbcn_handler(struct kvm_vcpu *vcpu, + struct kvm_run *run, + struct kvm_vcpu_sbi_return *retdata) +{ + struct kvm_cpu_context *cp = &vcpu->arch.guest_context; + unsigned long funcid = cp->a6; + + switch (funcid) { + case SBI_EXT_DBCN_CONSOLE_WRITE: + case SBI_EXT_DBCN_CONSOLE_READ: + case SBI_EXT_DBCN_CONSOLE_WRITE_BYTE: + /* + * The SBI debug console functions are unconditionally + * forwarded to the userspace. + */ + kvm_riscv_vcpu_sbi_forward(vcpu, run); + retdata->uexit = true; + break; + default: + retdata->err_val = SBI_ERR_NOT_SUPPORTED; + } + + return 0; +} + +const struct kvm_vcpu_sbi_extension vcpu_sbi_ext_dbcn = { + .extid_start = SBI_EXT_DBCN, + .extid_end = SBI_EXT_DBCN, + .default_unavail = true, + .handler = kvm_sbi_ext_dbcn_handler, +}; -- 2.34.1