From nobody Sat Oct 25 21:46:14 2025 Delivered-To: importer@patchew.org Received-SPF: pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) client-ip=208.118.235.17; envelope-from=qemu-devel-bounces+importer=patchew.org@nongnu.org; helo=lists.gnu.org; Authentication-Results: mx.zohomail.com; dkim=fail; spf=pass (zoho.com: domain of gnu.org designates 208.118.235.17 as permitted sender) smtp.mailfrom=qemu-devel-bounces+importer=patchew.org@nongnu.org Return-Path: Received: from lists.gnu.org (208.118.235.17 [208.118.235.17]) by mx.zohomail.com with SMTPS id 1521230374418165.14076064045935; Fri, 16 Mar 2018 12:59:34 -0700 (PDT) Received: from localhost ([::1]:59288 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ewvVf-0004TT-Vl for importer@patchew.org; Fri, 16 Mar 2018 15:59:28 -0400 Received: from eggs.gnu.org ([2001:4830:134:3::10]:40467) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ewvFR-0007en-3C for qemu-devel@nongnu.org; Fri, 16 Mar 2018 15:42:42 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ewvFN-0003qe-MD for qemu-devel@nongnu.org; Fri, 16 Mar 2018 15:42:41 -0400 Received: from mail-pl0-x242.google.com ([2607:f8b0:400e:c01::242]:33536) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1ewvFN-0003qP-Fh for qemu-devel@nongnu.org; Fri, 16 Mar 2018 15:42:37 -0400 Received: by mail-pl0-x242.google.com with SMTP id c11-v6so6503753plo.0 for ; Fri, 16 Mar 2018 12:42:37 -0700 (PDT) Received: from monty.com ([12.206.222.5]) by smtp.gmail.com with ESMTPSA id k24sm13780469pff.77.2018.03.16.12.42.35 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Fri, 16 Mar 2018 12:42:35 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sifive.com; s=google; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=elXEjrujeHBejLZefg5SAzL2dxTnnLrXWqzO68PGJuU=; b=e4wIcFgNiOLilC80AR3vgrg+tpSs56OxbCPxVR0homSm/0yxSKNChvRKMHxgIoiSKU wOOGtxNOy7bzPk8KgqRR0aC1j8EBFAMyYAHUp7OZDkO86T6EG7NN2eNt6LWLIuanD14w y5Ms9tuldqKr0m4jN20zAa57ik2EHpmrGbiaPKqMdFtZPEp3vBvq1YjT+pmlzN7BaCjU p232indweK4dwO3FZz0USFHJ7L3jdOWyxtimEDQX16GpL9JLkxRhdsp6OQvLs2KBR4lN EiZC9hw+6IAVbjs0qbbDfXuYKL1yI5tZhU7pnZfX8mm0jr1VN8gkiCxJZoRbwh+5Xk1q rzrQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=elXEjrujeHBejLZefg5SAzL2dxTnnLrXWqzO68PGJuU=; b=nV7EaPIsQXIK80F0P5fyF+j+OQBG8fBIIeOtAE4RcPwM/lugLqXsDojgKV5gm35gfQ Q9lZFrJV133DbnoZ1t6pFwebVZTQTt4nAJ+zu9feEZXE1uXlnCG3KnvmrfrSxGzDjNWg VzcwYE3Upit+wMQnh1YrNDOpAjHyjSbRvDEA4LKhHTU7uUSXddwiZF6SezWs9jaGnouM SR5FGSMHfXuuivqJbzO5ALBZcQ5UPQxSO2awO0L86CB7bmlDDriusUMStU3x58fMXxkR tpowB0OT97mEhcAih64dvCJfUaFCaKjMEsdkKw0rhv99sHQ59YKbNDyb86yv+1IYUwD+ uszQ== X-Gm-Message-State: AElRT7Hl8g/uuPWXaF6j5BPnSmbVUItERDqBSmW3Fm4wV0E08GUoZlVV Mt/rgemvBm4iBTgjGz7AZPffo7wffuo= X-Google-Smtp-Source: AG47ELu7DuGrdKAor8d521RbFZ8zFSTJ0shCC1zODIVIKaV05hJfwIADvi9KfgdQ5n90CDdCk12giw== X-Received: by 2002:a17:902:167:: with SMTP id 94-v6mr3390292plb.294.1521229356484; Fri, 16 Mar 2018 12:42:36 -0700 (PDT) From: Michael Clark To: qemu-devel@nongnu.org Date: Fri, 16 Mar 2018 12:41:18 -0700 Message-Id: <1521229281-73637-22-git-send-email-mjc@sifive.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1521229281-73637-1-git-send-email-mjc@sifive.com> References: <1521229281-73637-1-git-send-email-mjc@sifive.com> X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 2607:f8b0:400e:c01::242 Subject: [Qemu-devel] [PATCH v3 21/24] RISC-V: No traps on writes to misa, minstret, mcycle X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: patches@groups.riscv.org, Michael Clark , Palmer Dabbelt , Sagar Karandikar , Bastian Koppelmann Errors-To: qemu-devel-bounces+importer=patchew.org@nongnu.org Sender: "Qemu-devel" X-ZohoMail-DKIM: fail (Header signature does not verify) X-ZohoMail: RDKM_2 RSF_0 Z_629925259 SPT_0 Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" These fields are marked WARL in the specification so illegal writes are silently dropped. Cc: Sagar Karandikar Cc: Bastian Koppelmann Signed-off-by: Michael Clark Signed-off-by: Palmer Dabbelt --- target/riscv/op_helper.c | 26 +++++++++++++------------- 1 file changed, 13 insertions(+), 13 deletions(-) diff --git a/target/riscv/op_helper.c b/target/riscv/op_helper.c index aa101cc..f8595a6 100644 --- a/target/riscv/op_helper.c +++ b/target/riscv/op_helper.c @@ -200,17 +200,19 @@ void csr_write_helper(CPURISCVState *env, target_ulon= g val_to_write, break; } case CSR_MINSTRET: - qemu_log_mask(LOG_UNIMP, "CSR_MINSTRET: write not implemented"); - goto do_illegal; + /* minstret is WARL so unsupported writes are ignored */ + break; case CSR_MCYCLE: - qemu_log_mask(LOG_UNIMP, "CSR_MCYCLE: write not implemented"); - goto do_illegal; + /* mcycle is WARL so unsupported writes are ignored */ + break; +#if defined(TARGET_RISCV32) case CSR_MINSTRETH: - qemu_log_mask(LOG_UNIMP, "CSR_MINSTRETH: write not implemented"); - goto do_illegal; + /* minstreth is WARL so unsupported writes are ignored */ + break; case CSR_MCYCLEH: - qemu_log_mask(LOG_UNIMP, "CSR_MCYCLEH: write not implemented"); - goto do_illegal; + /* mcycleh is WARL so unsupported writes are ignored */ + break; +#endif case CSR_MUCOUNTEREN: env->mucounteren =3D val_to_write; break; @@ -300,10 +302,9 @@ void csr_write_helper(CPURISCVState *env, target_ulong= val_to_write, case CSR_MBADADDR: env->mbadaddr =3D val_to_write; break; - case CSR_MISA: { - qemu_log_mask(LOG_UNIMP, "CSR_MISA: misa writes not supported"); - goto do_illegal; - } + case CSR_MISA: + /* misa is WARL so unsupported writes are ignored */ + break; case CSR_PMPCFG0: case CSR_PMPCFG1: case CSR_PMPCFG2: @@ -328,7 +329,6 @@ void csr_write_helper(CPURISCVState *env, target_ulong = val_to_write, case CSR_PMPADDR15: pmpaddr_csr_write(env, csrno - CSR_PMPADDR0, val_to_write); break; - do_illegal: #endif default: do_raise_exception_err(env, RISCV_EXCP_ILLEGAL_INST, GETPC()); --=20 2.7.0