From patchwork Mon Dec 25 12:58:44 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Guo Ren X-Patchwork-Id: 13504657 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id BEF135576C; Mon, 25 Dec 2023 12:59:55 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="WJTNsleJ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5BCC1C433C8; Mon, 25 Dec 2023 12:59:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1703509195; bh=oQr4wuMlEBWYxpaVbDZM0YUteF5WonWqf5vY5cQvc88=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=WJTNsleJ/F9oBTs4gL7/Zk38ee+5vDE/bYOTwPr0JtYhW4QSxNI2Pn0dqn1l3Z/hP 47cT03H9LiKUD/fTnGxtz4G3an6tSqHhnSoORwyb4pl46iA/OAe2J++WBEm5X4ighK icXm6IXo/LkkqAPiHuGRDXNFPAecsDKaeqvEZJmz50J9M/AWIGs0iLYQafmgY9nasl esVXXomXaQc36WywqFMNqKdTX/bNO5zQBmXzDWvuAEaVOtk3LLsrFEyPnVa2zoOu6p xm+TQzhc2GFNjG8Ape4hWPCMo3alw/szyUPCQsLrBFsPX4SWrmotqtPUuX/a8LmbA1 v5PU1YhDHV4FQ== From: guoren@kernel.org To: paul.walmsley@sifive.com, palmer@dabbelt.com, guoren@kernel.org, panqinglin2020@iscas.ac.cn, bjorn@rivosinc.com, conor.dooley@microchip.com, leobras@redhat.com, peterz@infradead.org, anup@brainfault.org, keescook@chromium.org, wuwei2016@iscas.ac.cn, xiaoguang.xing@sophgo.com, chao.wei@sophgo.com, unicorn_wang@outlook.com, uwu@icenowy.me, jszhang@kernel.org, wefu@redhat.com, atishp@atishpatra.org Cc: linux-riscv@lists.infradead.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org, Guo Ren Subject: [PATCH V12 11/14] RISC-V: paravirt: pvqspinlock: Add SBI implementation Date: Mon, 25 Dec 2023 07:58:44 -0500 Message-Id: <20231225125847.2778638-12-guoren@kernel.org> X-Mailer: git-send-email 2.40.1 In-Reply-To: <20231225125847.2778638-1-guoren@kernel.org> References: <20231225125847.2778638-1-guoren@kernel.org> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Guo Ren Implement pv_kick with SBI guest implementation, and add SBI_EXT_PVLOCK extension detection. The backend part is in the KVM pvqspinlock patch. Reviewed-by: Leonardo Bras Signed-off-by: Guo Ren Signed-off-by: Guo Ren --- arch/riscv/include/asm/sbi.h | 6 ++++++ arch/riscv/kernel/qspinlock_paravirt.c | 7 ++++++- 2 files changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h index 8f748d9e1b85..318b3dd92958 100644 --- a/arch/riscv/include/asm/sbi.h +++ b/arch/riscv/include/asm/sbi.h @@ -31,6 +31,7 @@ enum sbi_ext_id { SBI_EXT_SRST = 0x53525354, SBI_EXT_PMU = 0x504D55, SBI_EXT_DBCN = 0x4442434E, + SBI_EXT_PVLOCK = 0xAB0401, /* Experimentals extensions must lie within this range */ SBI_EXT_EXPERIMENTAL_START = 0x08000000, @@ -250,6 +251,11 @@ enum sbi_ext_dbcn_fid { SBI_EXT_DBCN_CONSOLE_WRITE_BYTE = 2, }; +/* kick cpu out of wfi */ +enum sbi_ext_pvlock_fid { + SBI_EXT_PVLOCK_KICK_CPU = 0, +}; + #define SBI_SPEC_VERSION_DEFAULT 0x1 #define SBI_SPEC_VERSION_MAJOR_SHIFT 24 #define SBI_SPEC_VERSION_MAJOR_MASK 0x7f diff --git a/arch/riscv/kernel/qspinlock_paravirt.c b/arch/riscv/kernel/qspinlock_paravirt.c index 85ff5a3ec234..7d1b99412222 100644 --- a/arch/riscv/kernel/qspinlock_paravirt.c +++ b/arch/riscv/kernel/qspinlock_paravirt.c @@ -11,6 +11,8 @@ void pv_kick(int cpu) { + sbi_ecall(SBI_EXT_PVLOCK, SBI_EXT_PVLOCK_KICK_CPU, + cpuid_to_hartid_map(cpu), 0, 0, 0, 0, 0); return; } @@ -25,7 +27,7 @@ void pv_wait(u8 *ptr, u8 val) if (READ_ONCE(*ptr) != val) goto out; - /* wait_for_interrupt(); */ + wait_for_interrupt(); out: local_irq_restore(flags); } @@ -49,6 +51,9 @@ void __init pv_qspinlock_init(void) if(sbi_get_firmware_id() != SBI_EXT_BASE_IMPL_ID_KVM) return; + if (!sbi_probe_extension(SBI_EXT_PVLOCK)) + return; + pr_info("PV qspinlocks enabled\n"); __pv_init_lock_hash();