From patchwork Wed May 17 00:22:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Jiang X-Patchwork-Id: 13244035 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 42799C77B7F for ; Wed, 17 May 2023 00:22:43 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229873AbjEQAWm (ORCPT ); Tue, 16 May 2023 20:22:42 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49196 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229571AbjEQAWl (ORCPT ); Tue, 16 May 2023 20:22:41 -0400 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E81E40DF for ; Tue, 16 May 2023 17:22:40 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1684282960; x=1715818960; h=subject:from:to:cc:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=FfuHCjsxGv021VVLlcMhVC0faNRwGMJpc9tyv1OSH4Y=; b=WS6YNSkigSyJmaUB0FgHtA/m4JLaXgZrC1bLrqzL2uqV0aJsD5zG0DDG Ru41jgC00vocms9aEWGSphCizCo3waMYlh7Ir3xfuK7uBB3VBFNpzt9lR i3xLYHwi+yjuzD9d0leYPBIjjJH0R2qgbJBL+OU9F6MSQO1xEZjoPH3Rp zBv9ZxNscyS1RA9LoQZJ5m8+O9yuz6578zzOqcJGL/coHEglGyjVCLwna kVxtAUpv/ZD9bLgYQ4foVeJpypckYjpc6qJPBtQC/SQrUUXnDBqCFTRKh PxyQv4T9tQ5sGkBmX8yg0PDDKx5SHvIsgQHoQ/kUnnw1PFCcdtHDziXw+ g==; X-IronPort-AV: E=McAfee;i="6600,9927,10712"; a="350465324" X-IronPort-AV: E=Sophos;i="5.99,280,1677571200"; d="scan'208";a="350465324" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 May 2023 17:22:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6600,9927,10712"; a="679064086" X-IronPort-AV: E=Sophos;i="5.99,280,1677571200"; d="scan'208";a="679064086" Received: from djiang5-mobl3.amr.corp.intel.com (HELO [192.168.1.177]) ([10.212.5.122]) by orsmga006-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 May 2023 17:22:39 -0700 Subject: [PATCH 1/3] cxl: Wait Memory_Info_Valid before access memory related info From: Dave Jiang To: linux-cxl@vger.kernel.org, dan.j.williams@intel.com Cc: Jonathan Cameron , ira.weiny@intel.com, vishal.l.verma@intel.com, alison.schofield@intel.com Date: Tue, 16 May 2023 17:22:39 -0700 Message-ID: <168428295907.2205351.12793990978386772732.stgit@djiang5-mobl3> In-Reply-To: <168428284429.2205351.8883627879572769367.stgit@djiang5-mobl3> References: <168428284429.2205351.8883627879572769367.stgit@djiang5-mobl3> User-Agent: StGit/1.5 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org CXL rev3.0 8.1.3.8.2 Memory_Info_valid field The Memory_Info_Valid bit indicates that the CXL Range Size High and Size Low registers are valid. The bit must be set within 1 second of reset deassertion to the device. Check valid bit before we check the Memory_Active bit when waiting for cxl_await_media_ready() to ensure that the memory info is valid for consumption. Fixes: 2e4ba0ec9783 ("cxl/pci: Move cxl_await_media_ready() to the core") Reviewed-by: Jonathan Cameron Signed-off-by: Dave Jiang --- v2: - Check both ranges. (Jonathan) --- drivers/cxl/core/pci.c | 83 +++++++++++++++++++++++++++++++++++++++++++----- drivers/cxl/cxlpci.h | 2 + 2 files changed, 77 insertions(+), 8 deletions(-) diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index 63f2f0b86fbc..484a8b0b96b9 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -101,21 +101,55 @@ int devm_cxl_port_enumerate_dports(struct cxl_port *port) } EXPORT_SYMBOL_NS_GPL(devm_cxl_port_enumerate_dports, CXL); -/* - * Wait up to @media_ready_timeout for the device to report memory - * active. - */ -int cxl_await_media_ready(struct cxl_dev_state *cxlds) +static int cxl_dvsec_mem_range_valid(struct cxl_dev_state *cxlds, int id) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + bool valid = false; + int rc, i; + u32 temp; + + if (id > CXL_DVSEC_RANGE_MAX) + return -EINVAL; + + /* Check MEM INFO VALID bit first, give up after 1s */ + i = 1; + do { + rc = pci_read_config_dword(pdev, + d + CXL_DVSEC_RANGE_SIZE_LOW(id), + &temp); + if (rc) + return rc; + + valid = FIELD_GET(CXL_DVSEC_MEM_INFO_VALID, temp); + if (valid) + break; + msleep(1000); + } while (i--); + + if (!valid) { + dev_err(&pdev->dev, + "Timeout awaiting memory range %d valid after 1s.\n", + id); + return -ETIMEDOUT; + } + + return 0; +} + +static int cxl_dvsec_mem_range_active(struct cxl_dev_state *cxlds, int id) { struct pci_dev *pdev = to_pci_dev(cxlds->dev); int d = cxlds->cxl_dvsec; bool active = false; - u64 md_status; int rc, i; + u32 temp; - for (i = media_ready_timeout; i; i--) { - u32 temp; + if (id > CXL_DVSEC_RANGE_MAX) + return -EINVAL; + /* Check MEM ACTIVE bit, up to 60s timeout by default */ + for (i = media_ready_timeout; i; i--) { rc = pci_read_config_dword( pdev, d + CXL_DVSEC_RANGE_SIZE_LOW(0), &temp); if (rc) @@ -134,6 +168,39 @@ int cxl_await_media_ready(struct cxl_dev_state *cxlds) return -ETIMEDOUT; } + return 0; +} + +/* + * Wait up to @media_ready_timeout for the device to report memory + * active. + */ +int cxl_await_media_ready(struct cxl_dev_state *cxlds) +{ + struct pci_dev *pdev = to_pci_dev(cxlds->dev); + int d = cxlds->cxl_dvsec; + int rc, i, hdm_count; + u64 md_status; + u16 cap; + + rc = pci_read_config_word(pdev, + d + CXL_DVSEC_CAP_OFFSET, &cap); + if (rc) + return rc; + + hdm_count = FIELD_GET(CXL_DVSEC_HDM_COUNT_MASK, cap); + for (i = 0; i < hdm_count; i++) { + rc = cxl_dvsec_mem_range_valid(cxlds, i); + if (rc) + return rc; + } + + for (i = 0; i < hdm_count; i++) { + rc = cxl_dvsec_mem_range_active(cxlds, i); + if (rc) + return rc; + } + md_status = readq(cxlds->regs.memdev + CXLMDEV_STATUS_OFFSET); if (!CXLMDEV_READY(md_status)) return -EIO; diff --git a/drivers/cxl/cxlpci.h b/drivers/cxl/cxlpci.h index 0465ef963cd6..7c02e55b8042 100644 --- a/drivers/cxl/cxlpci.h +++ b/drivers/cxl/cxlpci.h @@ -31,6 +31,8 @@ #define CXL_DVSEC_RANGE_BASE_LOW(i) (0x24 + (i * 0x10)) #define CXL_DVSEC_MEM_BASE_LOW_MASK GENMASK(31, 28) +#define CXL_DVSEC_RANGE_MAX 2 + /* CXL 2.0 8.1.4: Non-CXL Function Map DVSEC */ #define CXL_DVSEC_FUNCTION_MAP 2