From patchwork Thu May 30 07:01:17 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Nick Hu X-Patchwork-Id: 10968297 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 8EB1F933 for ; Thu, 30 May 2019 07:01:50 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 7DC5628A52 for ; Thu, 30 May 2019 07:01:50 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 715C128A7E; Thu, 30 May 2019 07:01:50 +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,DKIM_SIGNED, DKIM_VALID,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED autolearn=ham version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id C197128A52 for ; Thu, 30 May 2019 07:01:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-ID:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=/uoFANIUBXnIDDwXUsvtJAeW9nwEDyHLMrzufOtPZpA=; b=NF+F8zh/tidWQO 0JLyWR1YK1q+nfEsrxgppqZc5DqK/Ge2ROvJ6fcJ8CYBX7Fhj1385Ey2l13slzTpMtFhuZWUXlXHk wW4B8ByVe/A40thEkOTIM4j8M2LjVap/p+JjihPmHK+D/5v0Vi0GjCbifNULrg6V7Mk4DzkHRneFM V1l5iIMYyQnrnNcCoOlDTlAobx3wBAvjUwtlxi516Ft4Xph5PjVHv6TS4z3cFpkzexTq5z+IQavif gMGIibxf8e+KIsXzgUyL9t2rf5sW8Ns9Z1AhpBhMjV40crbIhTi89QnFB+tmASRtS47tkcCOPFVdq x0VQd22HhZoB6Wo7P51Q==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.90_1 #2 (Red Hat Linux)) id 1hWF4K-0004cc-2n; Thu, 30 May 2019 07:01:44 +0000 Received: from 59-120-53-16.hinet-ip.hinet.net ([59.120.53.16] helo=ATCSQR.andestech.com) by bombadil.infradead.org with esmtps (Exim 4.90_1 #2 (Red Hat Linux)) id 1hWF4H-0004bj-09 for linux-riscv@lists.infradead.org; Thu, 30 May 2019 07:01:42 +0000 Received: from mail.andestech.com (atcpcs16.andestech.com [10.0.1.222]) by ATCSQR.andestech.com with ESMTP id x4U6tpgk061915; Thu, 30 May 2019 14:55:51 +0800 (GMT-8) (envelope-from nickhu@andestech.com) Received: from atcsqa06.andestech.com (10.0.15.65) by ATCPCS16.andestech.com (10.0.1.222) with Microsoft SMTP Server id 14.3.123.3; Thu, 30 May 2019 15:01:24 +0800 From: Nick Hu To: , , , , , Subject: [PATCH v3] riscv: Fix udelay in RV32. Date: Thu, 30 May 2019 15:01:17 +0800 Message-ID: <67bfbb11e64273427b125528a4e2bc83b5efe70b.1559199430.git.nickhu@andestech.com> X-Mailer: git-send-email 2.7.4 MIME-Version: 1.0 X-Originating-IP: [10.0.15.65] X-DNSRBL: X-MAIL: ATCSQR.andestech.com x4U6tpgk061915 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190530_000141_293362_A6B08FE0 X-CRM114-Status: UNSURE ( 8.18 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-riscv@lists.infradead.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: green.hu@gmail.com, Nick Hu Sender: "linux-riscv" Errors-To: linux-riscv-bounces+patchwork-linux-riscv=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP In RV32, udelay would delay the wrong cycle. When it shifts right "UDELAY_SHITFT" bits, it either delays 0 cycle or 1 cycle. It only works correctly in RV64. Because the 'ucycles' always needs to be 64 bits variable. Signed-off-by: Nick Hu Reviewed-by: Palmer Dabbelt --- arch/riscv/lib/delay.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/riscv/lib/delay.c b/arch/riscv/lib/delay.c index dce8ae24c6d3..ee6853c1e341 100644 --- a/arch/riscv/lib/delay.c +++ b/arch/riscv/lib/delay.c @@ -88,7 +88,7 @@ EXPORT_SYMBOL(__delay); void udelay(unsigned long usecs) { - unsigned long ucycles = usecs * lpj_fine * UDELAY_MULT; + u64 ucycles = (u64)usecs * lpj_fine * UDELAY_MULT; if (unlikely(usecs > MAX_UDELAY_US)) { __delay((u64)usecs * riscv_timebase / 1000000ULL);