From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx0b-001b2d01.pphosted.com ([148.163.158.5]:14494 "EHLO mx0a-001b2d01.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1729109AbgFHINO (ORCPT ); Mon, 8 Jun 2020 04:13:14 -0400 From: Pierre Morel Subject: [kvm-unit-tests PATCH v8 11/12] s390x: css: msch, enable test Date: Mon, 8 Jun 2020 10:13:00 +0200 Message-Id: <1591603981-16879-12-git-send-email-pmorel@linux.ibm.com> In-Reply-To: <1591603981-16879-1-git-send-email-pmorel@linux.ibm.com> References: <1591603981-16879-1-git-send-email-pmorel@linux.ibm.com> Sender: linux-s390-owner@vger.kernel.org List-ID: To: kvm@vger.kernel.org Cc: linux-s390@vger.kernel.org, frankja@linux.ibm.com, david@redhat.com, thuth@redhat.com, cohuck@redhat.com A second step when testing the channel subsystem is to prepare a channel for use. This includes: - Get the current subchannel Information Block (SCHIB) using STSCH - Update it in memory to set the ENABLE bit - Tell the CSS that the SCHIB has been modified using MSCH - Get the SCHIB from the CSS again to verify that the subchannel is enabled. - If the command succeeds but subchannel is not enabled retry a predefined retries count. - If the command fails, report the failure and do not retry, even if cc indicates a busy/status pending as we do not expect this. This tests the MSCH instruction to enable a channel succesfuly. This some retries are done and in case of error, and if the retries count is exceeded, a report is made. Signed-off-by: Pierre Morel --- lib/s390x/css_lib.c | 60 +++++++++++++++++++++++++++++++++++++++++++++ s390x/css.c | 18 ++++++++++++++ 2 files changed, 78 insertions(+) diff --git a/lib/s390x/css_lib.c b/lib/s390x/css_lib.c index dc5a512..831a116 100644 --- a/lib/s390x/css_lib.c +++ b/lib/s390x/css_lib.c @@ -15,6 +15,7 @@ #include #include #include +#include #include @@ -68,3 +69,62 @@ out: scn, scn_found, dev_found); return schid; } + +int css_enable(int schid) +{ + struct pmcw *pmcw = &schib.pmcw; + int retry_count = 0; + int cc; + + /* Read the SCHIB for this subchannel */ + cc = stsch(schid, &schib); + if (cc) { + report_info("stsch failed with cc=%d", cc); + return cc; + } + + if (pmcw->flags & PMCW_ENABLE) { + report_info("stsch: sch %08x already enabled", schid); + return 0; + } + +retry: + /* Update the SCHIB to enable the channel */ + pmcw->flags |= PMCW_ENABLE; + + /* Tell the CSS we want to modify the subchannel */ + cc = msch(schid, &schib); + if (cc) { + /* + * If the subchannel is status pending or + * if a function is in progress, + * we consider both cases as errors. + */ + report_info("msch failed with cc=%d", cc); + return cc; + } + + /* + * Read the SCHIB again to verify the enablement + */ + cc = stsch(schid, &schib); + if (cc) { + report_info("stsch failed with cc=%d", cc); + return cc; + } + + if (pmcw->flags & PMCW_ENABLE) { + report_info("Subchannel %08x enabled after %d retries", + schid, retry_count); + return 0; + } + + if (retry_count++ < MAX_ENABLE_RETRIES) { + mdelay(10); /* the hardware was not ready, give it some time */ + goto retry; + } + + report_info("msch: enabling sch %08x failed after %d retries. pmcw flags: %x", + schid, retry_count, pmcw->flags); + return -1; +} diff --git a/s390x/css.c b/s390x/css.c index f0e8f47..6f58d4a 100644 --- a/s390x/css.c +++ b/s390x/css.c @@ -40,11 +40,29 @@ static void test_enumerate(void) } } +static void test_enable(void) +{ + int cc; + + if (!test_device_sid) { + report_skip("No device"); + return; + } + + cc = css_enable(test_device_sid); + + if (cc) + report(0, "Failed to enable subchannel %08x", test_device_sid); + else + report(1, "Subchannel %08x enabled", test_device_sid); +} + static struct { const char *name; void (*func)(void); } tests[] = { { "enumerate (stsch)", test_enumerate }, + { "enable (msch)", test_enable }, { NULL, NULL } }; -- 2.25.1