From patchwork Thu Mar 3 13:59:01 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jonathan Cameron X-Patchwork-Id: 12767500 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 F212EC433EF for ; Thu, 3 Mar 2022 14:04:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231915AbiCCOEt (ORCPT ); Thu, 3 Mar 2022 09:04:49 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33526 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231287AbiCCOEs (ORCPT ); Thu, 3 Mar 2022 09:04:48 -0500 Received: from frasgout.his.huawei.com (frasgout.his.huawei.com [185.176.79.56]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 02A04419B9; Thu, 3 Mar 2022 06:04:03 -0800 (PST) Received: from fraeml708-chm.china.huawei.com (unknown [172.18.147.201]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4K8XkK29FXz67Nm9; Thu, 3 Mar 2022 22:02:49 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml708-chm.china.huawei.com (10.206.15.36) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2308.21; Thu, 3 Mar 2022 15:04:01 +0100 Received: from SecurePC-101-06.china.huawei.com (10.122.247.231) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_CBC_SHA256) id 15.1.2308.21; Thu, 3 Mar 2022 14:04:00 +0000 From: Jonathan Cameron To: , CC: , Lorenzo Pieralisi , Chris Browy , , "Bjorn Helgaas" , "David E . Box" , Subject: [RFC PATCH v2 10/14] cxl/cdat: Parse out DSMAS data from CDAT table Date: Thu, 3 Mar 2022 13:59:01 +0000 Message-ID: <20220303135905.10420-11-Jonathan.Cameron@huawei.com> X-Mailer: git-send-email 2.32.0 In-Reply-To: <20220303135905.10420-1-Jonathan.Cameron@huawei.com> References: <20220303135905.10420-1-Jonathan.Cameron@huawei.com> MIME-Version: 1.0 X-Originating-IP: [10.122.247.231] X-ClientProxiedBy: lhreml706-chm.china.huawei.com (10.201.108.55) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-cxl@vger.kernel.org From: Ira Weiny CXL memory devices need the information in the Device Scoped Memory Affinity Structure (DSMAS). This information is contained within the CDAT table buffer which is already read and cached. Parse and cache DSMAS data from the CDAT table. Store this data in unmarshaled struct dsmas data structures for ease of use. Signed-off-by: Ira Weiny Signed-off-by: Jonathan Cameron --- drivers/cxl/cdat.h | 21 ++++++++++++ drivers/cxl/core/memdev.c | 70 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 91 insertions(+) diff --git a/drivers/cxl/cdat.h b/drivers/cxl/cdat.h index a7725d26f2d2..f8c126190d18 100644 --- a/drivers/cxl/cdat.h +++ b/drivers/cxl/cdat.h @@ -83,17 +83,38 @@ #define CDAT_SSLBIS_ENTRY_PORT_Y(entry, i) (((entry)[4 + (i) * 2] & 0xffff0000) >> 16) #define CDAT_SSLBIS_ENTRY_LAT_OR_BW(entry, i) ((entry)[4 + (i) * 2 + 1] & 0x0000ffff) +/** + * struct cxl_dsmas - host unmarshaled version of DSMAS data + * + * As defined in the Coherent Device Attribute Table (CDAT) specification this + * represents a single DSMAS entry in that table. + * + * @dpa_base: The lowest DPA address associated with this DSMAD + * @dpa_length: Length in bytes of this DSMAD + * @non_volatile: If set, the memory region represents Non-Volatile memory + */ +struct cxl_dsmas { + u64 dpa_base; + u64 dpa_length; + /* Flags */ + u8 non_volatile:1; +}; + /** * struct cxl_cdat - CXL CDAT data * * @table: cache of CDAT table * @length: length of cached CDAT table * @seq: Last read Sequence number of the CDAT table + * @dsmas_ary: Array of DSMAS entries as parsed from the CDAT table + * @nr_dsmas: Number of entries in dsmas_ary */ struct cxl_cdat { void *table; size_t length; u32 seq; + struct cxl_dsmas *dsmas_ary; + int nr_dsmas; }; #endif /* !__CXL_CDAT_H__ */ diff --git a/drivers/cxl/core/memdev.c b/drivers/cxl/core/memdev.c index 66229ba2a0f8..2d909830918f 100644 --- a/drivers/cxl/core/memdev.c +++ b/drivers/cxl/core/memdev.c @@ -6,6 +6,7 @@ #include #include #include +#include "cdat.h" #include "core.h" static DECLARE_RWSEM(cxl_memdev_rwsem); @@ -342,6 +343,71 @@ static int read_cdat_data(struct cxl_memdev *cxlmd, return rc; } +static int parse_dsmas(struct cxl_memdev *cxlmd) +{ + struct cxl_dsmas *dsmas_ary = NULL; + u32 *data = cxlmd->cdat.table; + int bytes_left = cxlmd->cdat.length; + int nr_dsmas = 0; + + if (!data) + return -ENXIO; + + /* Skip header */ + data += CDAT_HEADER_LENGTH_DW; + bytes_left -= CDAT_HEADER_LENGTH_BYTES; + + while (bytes_left > 0) { + u32 *cur_rec = data; + u8 type = FIELD_GET(CDAT_STRUCTURE_DW0_TYPE, cur_rec[0]); + u16 length = FIELD_GET(CDAT_STRUCTURE_DW0_LENGTH, cur_rec[0]); + + if (type == CDAT_STRUCTURE_DW0_TYPE_DSMAS) { + struct cxl_dsmas *new_ary; + u8 flags; + + new_ary = devm_krealloc(&cxlmd->dev, dsmas_ary, + sizeof(*dsmas_ary) * (nr_dsmas + 1), + GFP_KERNEL); + if (!new_ary) { + dev_err(&cxlmd->dev, + "Failed to allocate memory for DSMAS data\n"); + return -ENOMEM; + } + dsmas_ary = new_ary; + + flags = FIELD_GET(CDAT_DSMAS_DW1_FLAGS, cur_rec[1]); + + dsmas_ary[nr_dsmas].dpa_base = CDAT_DSMAS_DPA_OFFSET(cur_rec); + dsmas_ary[nr_dsmas].dpa_length = CDAT_DSMAS_DPA_LEN(cur_rec); + dsmas_ary[nr_dsmas].non_volatile = CDAT_DSMAS_NON_VOLATILE(flags); + + dev_dbg(&cxlmd->dev, "DSMAS %d: %llx:%llx %s\n", + nr_dsmas, + dsmas_ary[nr_dsmas].dpa_base, + dsmas_ary[nr_dsmas].dpa_base + + dsmas_ary[nr_dsmas].dpa_length, + (dsmas_ary[nr_dsmas].non_volatile ? + "Persistent" : "Volatile") + ); + + nr_dsmas++; + } + + data += (length / sizeof(u32)); + bytes_left -= length; + } + + if (nr_dsmas == 0) + return -ENXIO; + + dev_dbg(&cxlmd->dev, "Found %d DSMAS entries\n", nr_dsmas); + cxlmd->cdat.dsmas_ary = dsmas_ary; + cxlmd->cdat.nr_dsmas = nr_dsmas; + + return 0; +} + struct cxl_memdev *devm_cxl_add_memdev(struct cxl_dev_state *cxlds) { struct cxl_memdev *cxlmd; @@ -363,6 +429,10 @@ struct cxl_memdev *devm_cxl_add_memdev(struct cxl_dev_state *cxlds) if (rc) goto err; + rc = parse_dsmas(cxlmd); + if (rc) + dev_warn(dev, "No DSMAS data found: %d\n", rc); + /* * Activate ioctl operations, no cxl_memdev_rwsem manipulation * needed as this is ordered with cdev_add() publishing the device.