From patchwork Mon Jun 8 08:12:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Pierre Morel X-Patchwork-Id: 11592747 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CFB9892A for ; Mon, 8 Jun 2020 08:13:43 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C12D72076A for ; Mon, 8 Jun 2020 08:13:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729175AbgFHINn (ORCPT ); Mon, 8 Jun 2020 04:13:43 -0400 Received: from mx0a-001b2d01.pphosted.com ([148.163.156.1]:8904 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1729095AbgFHINM (ORCPT ); Mon, 8 Jun 2020 04:13:12 -0400 Received: from pps.filterd (m0098393.ppops.net [127.0.0.1]) by mx0a-001b2d01.pphosted.com (8.16.0.42/8.16.0.42) with SMTP id 05885eDI015511; Mon, 8 Jun 2020 04:13:11 -0400 Received: from pps.reinject (localhost [127.0.0.1]) by mx0a-001b2d01.pphosted.com with ESMTP id 31g41dha8j-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 08 Jun 2020 04:13:11 -0400 Received: from m0098393.ppops.net (m0098393.ppops.net [127.0.0.1]) by pps.reinject (8.16.0.36/8.16.0.36) with SMTP id 05886mgH019826; Mon, 8 Jun 2020 04:13:10 -0400 Received: from ppma01fra.de.ibm.com (46.49.7a9f.ip4.static.sl-reverse.com [159.122.73.70]) by mx0a-001b2d01.pphosted.com with ESMTP id 31g41dha64-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 08 Jun 2020 04:13:10 -0400 Received: from pps.filterd (ppma01fra.de.ibm.com [127.0.0.1]) by ppma01fra.de.ibm.com (8.16.0.42/8.16.0.42) with SMTP id 05885LW3016173; Mon, 8 Jun 2020 08:13:08 GMT Received: from b06cxnps4074.portsmouth.uk.ibm.com (d06relay11.portsmouth.uk.ibm.com [9.149.109.196]) by ppma01fra.de.ibm.com with ESMTP id 31g2s7se9v-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=NOT); Mon, 08 Jun 2020 08:13:07 +0000 Received: from d06av22.portsmouth.uk.ibm.com (d06av22.portsmouth.uk.ibm.com [9.149.105.58]) by b06cxnps4074.portsmouth.uk.ibm.com (8.14.9/8.14.9/NCO v10.0) with ESMTP id 0588D5Xp59441350 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Mon, 8 Jun 2020 08:13:05 GMT Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id A11924C059; Mon, 8 Jun 2020 08:13:05 +0000 (GMT) Received: from d06av22.portsmouth.uk.ibm.com (unknown [127.0.0.1]) by IMSVA (Postfix) with ESMTP id 59BE24C040; Mon, 8 Jun 2020 08:13:05 +0000 (GMT) Received: from oc3016276355.ibm.com (unknown [9.145.43.245]) by d06av22.portsmouth.uk.ibm.com (Postfix) with ESMTP; Mon, 8 Jun 2020 08:13:05 +0000 (GMT) From: Pierre Morel To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, frankja@linux.ibm.com, david@redhat.com, thuth@redhat.com, cohuck@redhat.com Subject: [kvm-unit-tests PATCH v8 06/12] s390x: clock and delays caluculations Date: Mon, 8 Jun 2020 10:12:55 +0200 Message-Id: <1591603981-16879-7-git-send-email-pmorel@linux.ibm.com> X-Mailer: git-send-email 1.8.3.1 In-Reply-To: <1591603981-16879-1-git-send-email-pmorel@linux.ibm.com> References: <1591603981-16879-1-git-send-email-pmorel@linux.ibm.com> X-TM-AS-GCONF: 00 X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:6.0.216,18.0.687 definitions=2020-06-08_04:2020-06-08,2020-06-08 signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 mlxscore=0 phishscore=0 adultscore=0 malwarescore=0 impostorscore=0 clxscore=1015 mlxlogscore=916 bulkscore=0 suspectscore=1 cotscore=-2147483648 priorityscore=1501 spamscore=0 lowpriorityscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2004280000 definitions=main-2006080062 Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org The hardware gives us a good definition of the microsecond, let's keep this information and let the routine accessing the hardware keep all the information and return microseconds. Calculate delays in microseconds and take care about wrapping around zero. Define values with macros and use inlines to keep the milliseconds interface. Signed-off-by: Pierre Morel --- lib/s390x/asm/time.h | 29 +++++++++++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-) diff --git a/lib/s390x/asm/time.h b/lib/s390x/asm/time.h index 1791380..eb15941 100644 --- a/lib/s390x/asm/time.h +++ b/lib/s390x/asm/time.h @@ -13,14 +13,39 @@ #ifndef ASM_S390X_TIME_H #define ASM_S390X_TIME_H -static inline uint64_t get_clock_ms(void) +#define STCK_SHIFT (63 - 51) +#define STCK_MAX ((1 << (STCK_SHIFT + 1)) - 1) + +static inline uint64_t get_clock_us(void) { uint64_t clk; asm volatile(" stck %0 " : : "Q"(clk) : "memory"); /* Bit 51 is incrememented each microsecond */ - return (clk >> (63 - 51)) / 1000; + return clk >> STCK_SHIFT; +} + +static inline void udelay(unsigned long us) +{ + unsigned long startclk = get_clock_us(); + unsigned long c; + + do { + c = get_clock_us(); + if (c < startclk) + c += STCK_MAX; + } while (c < (startclk + us)); +} + +static inline void mdelay(unsigned long ms) +{ + udelay(ms * 1000); +} + +static inline uint64_t get_clock_ms(void) +{ + return get_clock_us() / 1000; } #endif