From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-15.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_2 autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id E5C7FC49EA2 for ; Thu, 17 Jun 2021 09:00:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C29A7613D5 for ; Thu, 17 Jun 2021 09:00:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230331AbhFQJCn (ORCPT ); Thu, 17 Jun 2021 05:02:43 -0400 Received: from frasgout.his.huawei.com ([185.176.79.56]:3262 "EHLO frasgout.his.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231341AbhFQJCj (ORCPT ); Thu, 17 Jun 2021 05:02:39 -0400 Received: from fraeml737-chm.china.huawei.com (unknown [172.18.147.200]) by frasgout.his.huawei.com (SkyGuard) with ESMTP id 4G5G3p5ZLLz6L7lv; Thu, 17 Jun 2021 16:50:46 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by fraeml737-chm.china.huawei.com (10.206.15.218) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 17 Jun 2021 11:00:30 +0200 Received: from localhost (10.52.126.9) by lhreml710-chm.china.huawei.com (10.201.108.61) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Thu, 17 Jun 2021 10:00:29 +0100 Date: Thu, 17 Jun 2021 10:00:22 +0100 From: Jonathan Cameron To: Alison Schofield CC: Ben Widawsky , Dan Williams , Ira Weiny , Vishal Verma , , , Subject: Re: [PATCH v3 2/2] cxl/acpi: Use the ACPI CFMWS to create static decoder objects Message-ID: <20210617100022.00004665@Huawei.com> In-Reply-To: References: Organization: Huawei Technologies Research and Development (UK) Ltd. X-Mailer: Claws Mail 3.17.8 (GTK+ 2.24.33; i686-w64-mingw32) MIME-Version: 1.0 Content-Type: text/plain; charset="US-ASCII" Content-Transfer-Encoding: 7bit X-Originating-IP: [10.52.126.9] X-ClientProxiedBy: lhreml719-chm.china.huawei.com (10.201.108.70) To lhreml710-chm.china.huawei.com (10.201.108.61) X-CFilter-Loop: Reflected Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, 16 Jun 2021 18:11:08 -0700 Alison Schofield wrote: > The ACPI CXL Early Discovery Table (CEDT) includes a list of CXL memory > resources in CXL Fixed Memory Window Structures (CFMWS). Retrieve each > CFMWS in the CEDT and add a cxl_decoder object to the root port (root0) > for each memory resource. > > Signed-off-by: Alison Schofield Reviewed-by: Jonathan Cameron > --- > drivers/cxl/acpi.c | 119 +++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 119 insertions(+) > > diff --git a/drivers/cxl/acpi.c b/drivers/cxl/acpi.c > index 852b5c270464..018f5ac73b78 100644 > --- a/drivers/cxl/acpi.c > +++ b/drivers/cxl/acpi.c > @@ -10,6 +10,123 @@ > > static struct acpi_table_header *acpi_cedt; > > +/* Encode defined in CXL 2.0 8.2.5.12.7 HDM Decoder Control Register */ > +#define CFMWS_INTERLEAVE_WAYS(x) (1 << (x)->interleave_ways) > +#define CFMWS_INTERLEAVE_GRANULARITY(x) ((x)->granularity + 8) > + > +static unsigned long cfmws_to_decoder_flags(int restrictions) > +{ > + unsigned long flags = 0; > + > + if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_TYPE2) > + flags |= CXL_DECODER_F_TYPE2; > + if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_TYPE3) > + flags |= CXL_DECODER_F_TYPE3; > + if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_VOLATILE) > + flags |= CXL_DECODER_F_RAM; > + if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_PMEM) > + flags |= CXL_DECODER_F_PMEM; > + if (restrictions & ACPI_CEDT_CFMWS_RESTRICT_FIXED) > + flags |= CXL_DECODER_F_LOCK; > + > + return flags; > +} > + > +static int cxl_acpi_cfmws_verify(struct device *dev, > + struct acpi_cedt_cfmws *cfmws) > +{ > + int expected_len; > + > + if (cfmws->interleave_arithmetic != ACPI_CEDT_CFMWS_ARITHMETIC_MODULO) { > + dev_err(dev, "CFMWS Unsupported Interleave Arithmetic\n"); > + return -EINVAL; > + } > + > + if (!IS_ALIGNED(cfmws->base_hpa, SZ_256M)) { > + dev_err(dev, "CFMWS Base HPA not 256MB aligned\n"); > + return -EINVAL; > + } > + > + if (!IS_ALIGNED(cfmws->window_size, SZ_256M)) { > + dev_err(dev, "CFMWS Window Size not 256MB aligned\n"); > + return -EINVAL; > + } > + > + expected_len = struct_size((cfmws), interleave_targets, > + CFMWS_INTERLEAVE_WAYS(cfmws)); > + > + if (cfmws->header.length < expected_len) { > + dev_err(dev, "CFMWS length %d less than expected %d\n", > + cfmws->header.length, expected_len); > + return -EINVAL; > + } > + > + if (cfmws->header.length > expected_len) > + dev_dbg(dev, "CFMWS length %d greater than expected %d\n", > + cfmws->header.length, expected_len); > + > + return 0; > +} > + > +static void cxl_add_cfmws_decoders(struct device *dev, > + struct cxl_port *root_port) > +{ > + struct acpi_cedt_cfmws *cfmws; > + struct cxl_decoder *cxld; > + acpi_size len, cur = 0; > + void *cedt_subtable; > + int rc; > + > + len = acpi_cedt->length - sizeof(*acpi_cedt); > + cedt_subtable = acpi_cedt + 1; > + > + while (cur < len) { > + struct acpi_cedt_header *c = cedt_subtable + cur; > + > + if (c->type != ACPI_CEDT_TYPE_CFMWS) { > + cur += c->length; > + continue; > + } > + > + cfmws = cedt_subtable + cur; > + > + if (dev_WARN_ONCE(dev, cfmws->header.length < sizeof(*cfmws), > + "CFMWS entry skipped: invalid length:%u\n", > + cfmws->header.length)) { > + cur += c->length; > + continue; > + } > + > + rc = cxl_acpi_cfmws_verify(dev, cfmws); > + if (rc) { > + dev_err(dev, "CFMWS range %#llx-%#llx not registered\n", > + cfmws->base_hpa, cfmws->base_hpa + > + cfmws->window_size - 1); > + cur += c->length; > + continue; > + } > + > + cxld = devm_cxl_add_decoder(dev, root_port, > + CFMWS_INTERLEAVE_WAYS(cfmws), > + cfmws->base_hpa, cfmws->window_size, > + CFMWS_INTERLEAVE_WAYS(cfmws), > + CFMWS_INTERLEAVE_GRANULARITY(cfmws), > + CXL_DECODER_EXPANDER, > + cfmws_to_decoder_flags(cfmws->restrictions)); > + > + if (IS_ERR(cxld)) { > + dev_err(dev, "Failed to add decoder for %#llx-%#llx\n", > + cfmws->base_hpa, cfmws->base_hpa + > + cfmws->window_size - 1); This sounds rather fatal... I guess it'll be exposed later as we won't have any means of using the decoder so we don't have to error out here though. > + } else { > + dev_dbg(dev, "add: %s range %#llx-%#llx\n", > + dev_name(&cxld->dev), cfmws->base_hpa, > + cfmws->base_hpa + cfmws->window_size - 1); > + } > + cur += c->length; > + } > +} > + > static struct acpi_cedt_chbs *cxl_acpi_match_chbs(struct device *dev, u32 uid) > { > struct acpi_cedt_chbs *chbs, *chbs_match = NULL; > @@ -271,6 +388,8 @@ static int cxl_acpi_probe(struct platform_device *pdev) > if (rc) > goto out; > > + cxl_add_cfmws_decoders(host, root_port); > + > /* > * Root level scanned with host-bridge as dports, now scan host-bridges > * for their role as CXL uports to their CXL-capable PCIe Root Ports.