From patchwork Wed Sep 21 21:02:42 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Jiang X-Patchwork-Id: 12984150 Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8EBFA7C for ; Wed, 21 Sep 2022 21:02:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1663794163; x=1695330163; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=GULeu/RFvUc9KSKnjHluC8brt8xJw9osYPaSSwzRAas=; b=NBhy/mPt93tbMZoRgX4WGICBNSb+rcUsO9+C7FLUY/7nIH/TmwjGr+O1 o7c9BK4rld3CU/uf3FmtRBLRIsCifpHaNNmi5N2Fe88O69gVSHWCc6dr7 k4uv3TG3j3oQMwy9j1dRqK3eOtPxatMIw3p+feQNDLfnfyM/ZW7yXUqPc En7E7jLkMOx+NGZ8RRMnd4WLBgFNoTlwRBRcCaqe1OYRKbHa5PuMMr+2j DN6tSpZOen1TuUTTXQIquqpSeOAUpSU9DZr0VDkz6jg6j818HtOb3kXck r2N3oOimDN/WYj9iWs0ODKEz7kdiFPDyhW7FfRazU8N5G0MsiN6avZ2CO w==; X-IronPort-AV: E=McAfee;i="6500,9779,10477"; a="279848610" X-IronPort-AV: E=Sophos;i="5.93,334,1654585200"; d="scan'208";a="279848610" Received: from fmsmga008.fm.intel.com ([10.253.24.58]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Sep 2022 14:02:42 -0700 X-IronPort-AV: E=Sophos;i="5.93,334,1654585200"; d="scan'208";a="681934762" Received: from djiang5-desk3.ch.intel.com ([143.182.136.137]) by fmsmga008-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Sep 2022 14:02:42 -0700 Subject: [PATCH 1/4] ndctl: add cxl bus detection From: Dave Jiang To: linux-cxl@vger.kernel.org, nvdimm@lists.linux.dev Cc: vishal.l.verma@intel.com Date: Wed, 21 Sep 2022 14:02:42 -0700 Message-ID: <166379416245.433612.3109623615684575549.stgit@djiang5-desk3.ch.intel.com> In-Reply-To: <166379397620.433612.13099557870939895846.stgit@djiang5-desk3.ch.intel.com> References: <166379397620.433612.13099557870939895846.stgit@djiang5-desk3.ch.intel.com> User-Agent: StGit/1.4 Precedence: bulk X-Mailing-List: nvdimm@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Add helper function to detect that the bus is cxl based. Signed-off-by: Dave Jiang Reviewed-by: Alison Schofield --- ndctl/lib/libndctl.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++ ndctl/lib/libndctl.sym | 1 + ndctl/lib/private.h | 1 + ndctl/libndctl.h | 1 + 4 files changed, 56 insertions(+) diff --git a/ndctl/lib/libndctl.c b/ndctl/lib/libndctl.c index ad54f0626510..10422e24d38b 100644 --- a/ndctl/lib/libndctl.c +++ b/ndctl/lib/libndctl.c @@ -12,6 +12,7 @@ #include #include #include +#include #include #include #include @@ -876,6 +877,48 @@ static enum ndctl_fwa_method fwa_method_to_method(const char *fwa_method) return NDCTL_FWA_METHOD_RESET; } +static int is_ndbus_cxl(const char *ctl_base) +{ + char *path, *ppath, *subsys; + char tmp_path[PATH_MAX]; + int rc; + + /* get the real path of ctl_base */ + path = realpath(ctl_base, NULL); + if (!path) + return -errno; + + /* setup to get the nd bridge device backing the ctl */ + sprintf(tmp_path, "%s/device", path); + free(path); + + path = realpath(tmp_path, NULL); + if (!path) + return -errno; + + /* get the parent dir of the ndbus, which should be the nvdimm-bridge */ + ppath = dirname(path); + + /* setup to get the subsystem of the nvdimm-bridge */ + sprintf(tmp_path, "%s/%s", ppath, "subsystem"); + free(path); + + path = realpath(tmp_path, NULL); + if (!path) + return -errno; + + subsys = basename(path); + + /* check if subsystem is cxl */ + if (!strcmp(subsys, "cxl")) + rc = 1; + else + rc = 0; + + free(path); + return rc; +} + static void *add_bus(void *parent, int id, const char *ctl_base) { char buf[SYSFS_ATTR_SIZE]; @@ -919,6 +962,11 @@ static void *add_bus(void *parent, int id, const char *ctl_base) else bus->has_of_node = 1; + if (is_ndbus_cxl(ctl_base)) + bus->has_cxl = 1; + else + bus->has_cxl = 0; + sprintf(path, "%s/device/nfit/dsm_mask", ctl_base); if (sysfs_read_attr(ctx, path, buf) < 0) bus->nfit_dsm_mask = 0; @@ -1050,6 +1098,11 @@ NDCTL_EXPORT int ndctl_bus_has_of_node(struct ndctl_bus *bus) return bus->has_of_node; } +NDCTL_EXPORT int ndctl_bus_has_cxl(struct ndctl_bus *bus) +{ + return bus->has_cxl; +} + NDCTL_EXPORT int ndctl_bus_is_papr_scm(struct ndctl_bus *bus) { char buf[SYSFS_ATTR_SIZE]; diff --git a/ndctl/lib/libndctl.sym b/ndctl/lib/libndctl.sym index c933163c0380..3a3e8bbd63ef 100644 --- a/ndctl/lib/libndctl.sym +++ b/ndctl/lib/libndctl.sym @@ -465,4 +465,5 @@ LIBNDCTL_27 { LIBNDCTL_28 { ndctl_dimm_disable_master_passphrase; + ndctl_bus_has_cxl; } LIBNDCTL_27; diff --git a/ndctl/lib/private.h b/ndctl/lib/private.h index e5c56295556d..46bc8908bd90 100644 --- a/ndctl/lib/private.h +++ b/ndctl/lib/private.h @@ -163,6 +163,7 @@ struct ndctl_bus { int regions_init; int has_nfit; int has_of_node; + int has_cxl; char *bus_path; char *bus_buf; size_t buf_len; diff --git a/ndctl/libndctl.h b/ndctl/libndctl.h index c52e82a6f826..91ef0f42f654 100644 --- a/ndctl/libndctl.h +++ b/ndctl/libndctl.h @@ -133,6 +133,7 @@ struct ndctl_bus *ndctl_bus_get_next(struct ndctl_bus *bus); struct ndctl_ctx *ndctl_bus_get_ctx(struct ndctl_bus *bus); int ndctl_bus_has_nfit(struct ndctl_bus *bus); int ndctl_bus_has_of_node(struct ndctl_bus *bus); +int ndctl_bus_has_cxl(struct ndctl_bus *bus); int ndctl_bus_is_papr_scm(struct ndctl_bus *bus); unsigned int ndctl_bus_get_major(struct ndctl_bus *bus); unsigned int ndctl_bus_get_minor(struct ndctl_bus *bus);