From patchwork Wed Mar 22 00:33:57 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Joseph, Jithu" X-Patchwork-Id: 13183418 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 7FD27C76195 for ; Wed, 22 Mar 2023 00:38:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229872AbjCVAiN (ORCPT ); Tue, 21 Mar 2023 20:38:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:57464 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229841AbjCVAiJ (ORCPT ); Tue, 21 Mar 2023 20:38:09 -0400 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 753AD903B; Tue, 21 Mar 2023 17:38:07 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1679445487; x=1710981487; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=Jo23zFkwsDwbXcptMJ4++GJBxyXgWzFG3F/uuQmQl5Q=; b=gaLcHnpAAbed5hukxpasQuKmRIoCiTSLhsJJl1vFpYT5XPJVPirAr6Mu Qz/Ze/s31kSAFnUji9aNwhzFCWHS5zY5Vo1SCiJumLhpECMs7xkyHYEuK TwUloyyc2gC7mmDCcKbNJpCzTALweISut7II7+ULgrAM6Uh2HdFMvuAIF wGI6rt/XEpUAkXb3EqL5K4n3gZWWasKMDXz3FdikUyTJzCGUEoUBJEpSO UvNysFw5mVTGN2YQE7D64HJ+ZgueaTe7idjlC7h56xwbhZhzYUAmUDqlO 5Hsl1smBfPMO4w9pl5y438AIr354gaEnEyJJaxH+ysdy3wzxTiLR1JFCo Q==; X-IronPort-AV: E=McAfee;i="6600,9927,10656"; a="322934949" X-IronPort-AV: E=Sophos;i="5.98,280,1673942400"; d="scan'208";a="322934949" Received: from orsmga007.jf.intel.com ([10.7.209.58]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Mar 2023 17:38:07 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10656"; a="675076061" X-IronPort-AV: E=Sophos;i="5.98,280,1673942400"; d="scan'208";a="675076061" Received: from jithujos.sc.intel.com ([172.25.103.66]) by orsmga007-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Mar 2023 17:38:06 -0700 From: Jithu Joseph To: hdegoede@redhat.com, markgross@kernel.org Cc: tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, hpa@zytor.com, gregkh@linuxfoundation.org, rostedt@goodmis.org, jithu.joseph@intel.com, ashok.raj@intel.com, tony.luck@intel.com, linux-kernel@vger.kernel.org, platform-driver-x86@vger.kernel.org, patches@lists.linux.dev, ravi.v.shankar@intel.com, thiago.macieira@intel.com, athenas.jimenez.gonzalez@intel.com, sohil.mehta@intel.com Subject: [PATCH v4 7/9] platform/x86/intel/ifs: Implement Array BIST test Date: Tue, 21 Mar 2023 17:33:57 -0700 Message-Id: <20230322003359.213046-8-jithu.joseph@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20230322003359.213046-1-jithu.joseph@intel.com> References: <20230301015942.462799-1-jithu.joseph@intel.com> <20230322003359.213046-1-jithu.joseph@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org Array BIST test (for a particular core) is triggered by writing to MSR_ARRAY_BIST from one sibling of the core. This will initiate a test for all supported arrays on that CPU. Array BIST test may be aborted before completing all the arrays in the event of an interrupt or other reasons. In this case, kernel will restart the test from that point onwards. Array test will also be aborted when the test fails, in which case the test is stopped immediately without further retry. Signed-off-by: Jithu Joseph Reviewed-by: Tony Luck --- drivers/platform/x86/intel/ifs/ifs.h | 12 ++++ drivers/platform/x86/intel/ifs/runtest.c | 81 ++++++++++++++++++++++++ 2 files changed, 93 insertions(+) diff --git a/drivers/platform/x86/intel/ifs/ifs.h b/drivers/platform/x86/intel/ifs/ifs.h index a7d87fb4c412..048131df13bc 100644 --- a/drivers/platform/x86/intel/ifs/ifs.h +++ b/drivers/platform/x86/intel/ifs/ifs.h @@ -127,6 +127,7 @@ #include #include +#define MSR_ARRAY_BIST 0x00000105 #define MSR_COPY_SCAN_HASHES 0x000002c2 #define MSR_SCAN_HASHES_STATUS 0x000002c3 #define MSR_AUTHENTICATE_AND_COPY_CHUNK 0x000002c4 @@ -192,6 +193,17 @@ union ifs_status { }; }; +/* MSR_ARRAY_BIST bit fields */ +union ifs_array { + u64 data; + struct { + u32 array_bitmask; + u16 array_bank; + u16 rsvd :15; + u16 ctrl_result :1; + }; +}; + /* * Driver populated error-codes * 0xFD: Test timed out before completing all the chunks. diff --git a/drivers/platform/x86/intel/ifs/runtest.c b/drivers/platform/x86/intel/ifs/runtest.c index 323752fe5034..1061eb7ec399 100644 --- a/drivers/platform/x86/intel/ifs/runtest.c +++ b/drivers/platform/x86/intel/ifs/runtest.c @@ -229,6 +229,85 @@ static void ifs_test_core(int cpu, struct device *dev) } } +#define SPINUNIT 100 /* 100 nsec */ +static atomic_t array_cpus_out; + +/* + * Simplified cpu sibling rendezvous loop based on microcode loader __wait_for_cpus() + */ +static void wait_for_sibling_cpu(atomic_t *t, long long timeout) +{ + int cpu = smp_processor_id(); + const struct cpumask *smt_mask = cpu_smt_mask(cpu); + int all_cpus = cpumask_weight(smt_mask); + + atomic_inc(t); + while (atomic_read(t) < all_cpus) { + if (timeout < SPINUNIT) + return; + ndelay(SPINUNIT); + timeout -= SPINUNIT; + touch_nmi_watchdog(); + } +} + +static int do_array_test(void *data) +{ + union ifs_array *command = data; + int cpu = smp_processor_id(); + int first; + + /* + * Only one logical CPU on a core needs to trigger the Array test via MSR write. + */ + first = cpumask_first(cpu_smt_mask(cpu)); + + if (cpu == first) { + wrmsrl(MSR_ARRAY_BIST, command->data); + /* Pass back the result of the test */ + rdmsrl(MSR_ARRAY_BIST, command->data); + } + + /* Tests complete faster if the sibling is spinning here */ + wait_for_sibling_cpu(&array_cpus_out, NSEC_PER_SEC); + + return 0; +} + +static void ifs_array_test_core(int cpu, struct device *dev) +{ + union ifs_array command = {}; + bool timed_out = false; + struct ifs_data *ifsd; + unsigned long timeout; + + ifsd = ifs_get_data(dev); + + command.array_bitmask = ~0U; + timeout = jiffies + HZ / 2; + + do { + if (time_after(jiffies, timeout)) { + timed_out = true; + break; + } + atomic_set(&array_cpus_out, 0); + stop_core_cpuslocked(cpu, do_array_test, &command); + + if (command.ctrl_result) + break; + } while (command.array_bitmask); + + ifsd->scan_details = command.data; + + if (command.ctrl_result) + ifsd->status = SCAN_TEST_FAIL; + else if (timed_out || command.array_bitmask) + ifsd->status = SCAN_NOT_TESTED; + else + ifsd->status = SCAN_TEST_PASS; +} + /* * Initiate per core test. It wakes up work queue threads on the target cpu and * its sibling cpu. Once all sibling threads wake up, the scan test gets executed and @@ -256,6 +335,8 @@ int do_core_test(int cpu, struct device *dev) ifs_test_core(cpu, dev); break; case IFS_TYPE_ARRAY_BIST: + ifs_array_test_core(cpu, dev); + break; default: return -EINVAL; }