From patchwork Tue Aug 13 22:53:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Palmer Dabbelt X-Patchwork-Id: 11092989 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id C169C1398 for ; Tue, 13 Aug 2019 22:55:12 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B30112875E for ; Tue, 13 Aug 2019 22:55:12 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A6F41287BB; Tue, 13 Aug 2019 22:55:12 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.2 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id 4DC89287B9 for ; Tue, 13 Aug 2019 22:55:12 +0000 (UTC) Received: from localhost ([::1]:56030 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hxfh9-0006iL-JO for patchwork-qemu-devel@patchwork.kernel.org; Tue, 13 Aug 2019 18:55:11 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:56723) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hxfgl-0005te-Dp for qemu-devel@nongnu.org; Tue, 13 Aug 2019 18:54:48 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hxfgk-0006UT-Gx for qemu-devel@nongnu.org; Tue, 13 Aug 2019 18:54:47 -0400 Received: from mail-pf1-f195.google.com ([209.85.210.195]:40316) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1hxfgk-0006UB-CZ for qemu-devel@nongnu.org; Tue, 13 Aug 2019 18:54:46 -0400 Received: by mail-pf1-f195.google.com with SMTP id p184so52431713pfp.7 for ; Tue, 13 Aug 2019 15:54:46 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:subject:date:message-id:mime-version :content-transfer-encoding:cc:from:to; bh=9hzQDp4ZaD0ACnDOE3HEeTilvKbeiwOSKUnAotgimJQ=; b=udk6OMbyR0RLczvNKY2UdOoEsEyFyR0rHI4t/d3/qaZEI/ulcLeZzthuGm9fY107ah 75wCTVXAeq2xHiT3iFuoOyWzSaGHeNtz94QTfijGyQ0R3BZwmjrBDkwuZEEjvoc9SqP3 abp4aMzyIaFXdgv9bNTyCkdjAsxWnOJGMHLX0KLiqZLu3ZA0zeVTHvw0l0NIMQ1VF5AH mGvvrwJTwc+BJP7NQYAlP1WqCnIjjTLRX7sb5PD6uuG+MvO+FUN2m9UhrDl751yVmSQm sLW95LjAnlr3WDm4QdLKtBD4WMjzulHH27ffrPvZA3sIM5B+UjUc3QSURHt+NP0sBliO JwCQ== X-Gm-Message-State: APjAAAWb/2NH5i/UrI6INvhYFeun3f4Rh7pcbIoRZkfGc8z/DQsaSj8J LwRukEPk7Qc93Qaa/UzWu4y5WgWNhRo= X-Google-Smtp-Source: APXvYqxotfhbhfvjziG8ocdUpOtNFpDWKhIFFk8kTQRMLIb+3/PvuqOYJpTIBqfPScCSSuomLZXqUw== X-Received: by 2002:a63:e70f:: with SMTP id b15mr36374923pgi.152.1565736884691; Tue, 13 Aug 2019 15:54:44 -0700 (PDT) Received: from localhost ([12.206.222.5]) by smtp.gmail.com with ESMTPSA id w10sm3258290pjv.23.2019.08.13.15.54.43 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 13 Aug 2019 15:54:44 -0700 (PDT) Date: Tue, 13 Aug 2019 15:53:07 -0700 Message-Id: <20190813225307.5792-1-palmer@sifive.com> X-Mailer: git-send-email 2.21.0 MIME-Version: 1.0 From: Palmer Dabbelt To: Alistair Francis , qemu-riscv@nongnu.org X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] [fuzzy] X-Received-From: 209.85.210.195 Subject: [Qemu-devel] [PATCH v2] RISC-V: Ignore the S and U letters when formatting ISA strings X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Palmer Dabbelt , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP The ISA strings we're providing from QEMU aren't actually legal RISC-V ISA strings, as both S and U cannot exist as single-letter extensions and must instead be multi-letter strings. We're still using the ISA strings inside QEMU to track the availiable extensions, so this patch just strips out the S and U extensions when formatting ISA strings. This boots Linux on top of 4.1-rc3, which no longer has the U extension in /proc/cpuinfo. Signed-off-by: Palmer Dabbelt Reviewed-by: Alistair Francis --- target/riscv/cpu.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/target/riscv/cpu.c b/target/riscv/cpu.c index f8d07bd20ad7..a67c54c738ba 100644 --- a/target/riscv/cpu.c +++ b/target/riscv/cpu.c @@ -501,7 +501,23 @@ char *riscv_isa_string(RISCVCPU *cpu) char *p = isa_str + snprintf(isa_str, maxlen, "rv%d", TARGET_LONG_BITS); for (i = 0; i < sizeof(riscv_exts); i++) { if (cpu->env.misa & RV(riscv_exts[i])) { - *p++ = qemu_tolower(riscv_exts[i]); + char lower = qemu_tolower(riscv_exts[i]); + switch (lower) { + case 's': + case 'u': + /* + * The 's' and 'u' letters shouldn't show up in ISA strings as + * they're not extensions, but they should show up in MISA. + * Since we use these letters interally as a pseudo ISA string + * to set MISA it's easier to just strip them out when + * formatting the ISA string. + */ + break; + + default: + *p++ = lower; + break; + } } } *p = '\0';