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=-20.2 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,MENTIONS_GIT_HOSTING,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED, USER_AGENT_SANE_2 autolearn=ham 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 50925C2B9F8 for ; Tue, 25 May 2021 14:30:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 25AA26140B for ; Tue, 25 May 2021 14:30:54 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233635AbhEYOcX (ORCPT ); Tue, 25 May 2021 10:32:23 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:6709 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233406AbhEYOcW (ORCPT ); Tue, 25 May 2021 10:32:22 -0400 Received: from dggems704-chm.china.huawei.com (unknown [172.30.72.59]) by szxga04-in.huawei.com (SkyGuard) with ESMTP id 4FqGcd4rkszlYWh; Tue, 25 May 2021 22:27:13 +0800 (CST) Received: from lhreml710-chm.china.huawei.com (10.201.108.61) by dggems704-chm.china.huawei.com (10.3.19.181) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2176.2; Tue, 25 May 2021 22:30:49 +0800 Received: from localhost (10.52.120.147) 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 15.1.2176.2; Tue, 25 May 2021 15:30:46 +0100 Date: Tue, 25 May 2021 15:28:58 +0100 From: Jonathan Cameron To: CC: Ben Widawsky , Dan Williams , Vishal Verma , "Alison Schofield" , , Subject: Re: [PATCH v2 5/5] cxl: Add HDM decoder capbilities Message-ID: <20210525152858.00006a4a@Huawei.com> In-Reply-To: <20210522001154.2680157-6-ira.weiny@intel.com> References: <20210522001154.2680157-1-ira.weiny@intel.com> <20210522001154.2680157-6-ira.weiny@intel.com> 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: [10.52.120.147] X-ClientProxiedBy: lhreml705-chm.china.huawei.com (10.201.108.54) 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 On Fri, 21 May 2021 17:11:54 -0700 wrote: > From: Ben Widawsky > > An HDM decoder is defined in the CXL 2.0 specification as a mechanism > that allow devices and upstream ports to claim memory address ranges and > participate in interleave sets. HDM decoder registers are within the > component register block defined in CXL 2.0 8.2.3 CXL 2.0 Component > Registers as part of the CXL.cache and CXL.mem subregion. > > The Component Register Block is found via the Register Locator DVSEC > in a similar fashion to how the CXL Device Register Block is found. The > primary difference is the capability id size of the Component Register > Block is a single DWORD instead of 4 DWORDS. > > It's now possible to configure a CXL type 3 device's HDM decoder. Such > programming is expected for CXL devices with persistent memory, and hot > plugged CXL devices that participate in CXL.mem with volatile memory. > > Co-developed-by: Ira Weiny > Signed-off-by: Ira Weiny > Co-developed-by: Vishal Verma > Signed-off-by: Vishal Verma > Signed-off-by: Ben Widawsky Totally trivial comments inline. Otherwise LGTM Reviewed-by: Jonathan Cameron > > --- > Version 1: > Link: https://lore.kernel.org/r/20210407222625.320177-8-ben.widawsky@intel.com > Message-Id: <20210407222625.320177-8-ben.widawsky@intel.com> > > Changes for V2: > Rebased on https://git.kernel.org/pub/scm/linux/kernel/git/cxl/cxl.git/commit/?h=pending > From Dan > Remove version checking > Remove unneeded TODO/FIXME comments > --- > drivers/cxl/core.c | 81 ++++++++++++++++++++++++++++++++++++++++++++++ > drivers/cxl/cxl.h | 65 +++++++++++++++++++++++++++++++++---- > drivers/cxl/pci.c | 15 +++++++++ > drivers/cxl/pci.h | 1 + > 4 files changed, 156 insertions(+), 6 deletions(-) > > diff --git a/drivers/cxl/core.c b/drivers/cxl/core.c > index ae38f17be1e7..c0ced872a48d 100644 > --- a/drivers/cxl/core.c > +++ b/drivers/cxl/core.c > @@ -13,6 +13,67 @@ > * point for cross-device interleave coordination through cxl ports. > */ > > +void cxl_probe_component_regs(struct device *dev, void __iomem *base, > + struct cxl_component_reg_map *map) > +{ > + int cap, cap_count; > + u64 cap_array; > + > + *map = (struct cxl_component_reg_map) { 0 }; > + > + /* > + * CXL.cache and CXL.mem registers are at offset 0x1000 as defined in > + * CXL 2.0 8.2.4 Table 141. Perhaps makes more sense to have this next to the define? > + */ > + base += CXL_CM_OFFSET; > + > + cap_array = readq(base + CXL_CM_CAP_HDR_OFFSET); > + > + if (FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, cap_array) != CM_CAP_HDR_CAP_ID) { > + dev_err(dev, > + "Couldn't locate the CXL.cache and CXL.mem capability array header./n"); > + return; > + } > + > + /* It's assumed that future versions will be backward compatible */ > + cap_count = FIELD_GET(CXL_CM_CAP_HDR_ARRAY_SIZE_MASK, cap_array); > + > + for (cap = 1; cap <= cap_count; cap++) { > + void __iomem *register_block; > + u32 hdr; > + int decoder_cnt; > + u16 cap_id, offset; > + u32 length; > + > + hdr = readl(base + cap * 0x4); > + > + cap_id = FIELD_GET(CXL_CM_CAP_HDR_ID_MASK, hdr); > + offset = FIELD_GET(CXL_CM_CAP_PTR_MASK, hdr); > + register_block = base + offset; > + > + switch (cap_id) { > + case CXL_CM_CAP_CAP_ID_HDM: > + dev_dbg(dev, "found HDM decoder capability (0x%x)\n", > + offset); > + > + hdr = readl(register_block); > + > + decoder_cnt = FIELD_GET(CXL_HDM_DECODER_COUNT_MASK, hdr); > + length = 0x20 * decoder_cnt + 0x10; > + > + map->hdm_decoder.valid = true; > + map->hdm_decoder.offset = offset; > + map->hdm_decoder.size = length; > + break; > + default: > + dev_dbg(dev, "Unknown CM cap ID: %d (0x%x)\n", cap_id, > + offset); > + break; > + } > + } > +} > +EXPORT_SYMBOL_GPL(cxl_probe_component_regs); > + > void cxl_probe_device_regs(struct device *dev, void __iomem *base, > struct cxl_device_reg_map *map) > { > @@ -97,6 +158,26 @@ static void __iomem *cxl_ioremap_block(struct pci_dev *pdev, > return ret_val; > } > > +int cxl_map_component_regs(struct pci_dev *pdev, > + struct cxl_component_regs *regs, > + struct cxl_register_map *map) > +{ > + resource_size_t phys_addr; > + resource_size_t length; > + > + phys_addr = pci_resource_start(pdev, map->barno); > + phys_addr += map->block_offset; > + > + phys_addr += map->component_map.hdm_decoder.offset; > + length = map->component_map.hdm_decoder.size; > + regs->hdm_decoder = cxl_ioremap_block(pdev, phys_addr, length); > + if (!regs->hdm_decoder) > + return -ENOMEM; > + > + return 0; > +} > +EXPORT_SYMBOL_GPL(cxl_map_component_regs); > + > int cxl_map_device_regs(struct pci_dev *pdev, > struct cxl_device_regs *regs, > struct cxl_register_map *map) > diff --git a/drivers/cxl/cxl.h b/drivers/cxl/cxl.h > index ae4b4c96c6b5..2c47e9cffd44 100644 > --- a/drivers/cxl/cxl.h > +++ b/drivers/cxl/cxl.h > @@ -8,6 +8,31 @@ > #include > #include > > +/* CXL 2.0 8.2.5 CXL.cache and CXL.mem Registers*/ > +#define CXL_CM_OFFSET 0x1000 > +#define CXL_CM_CAP_HDR_OFFSET 0x0 > +#define CXL_CM_CAP_HDR_ID_MASK GENMASK(15, 0) > +#define CM_CAP_HDR_CAP_ID 1 > +#define CXL_CM_CAP_HDR_VERSION_MASK GENMASK(19, 16) > +#define CM_CAP_HDR_CAP_VERSION 1 > +#define CXL_CM_CAP_HDR_CACHE_MEM_VERSION_MASK GENMASK(23, 20) > +#define CM_CAP_HDR_CACHE_MEM_VERSION 1 > +#define CXL_CM_CAP_HDR_ARRAY_SIZE_MASK GENMASK(31, 24) > +#define CXL_CM_CAP_PTR_MASK GENMASK(31, 20) > + > +#define CXL_CM_CAP_CAP_ID_HDM 0x5 > +#define CXL_CM_CAP_CAP_HDM_VERSION 1 > + > +/* HDM decoders CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure */ > +#define CXL_HDM_DECODER_CAP_OFFSET 0x0 > +#define CXL_HDM_DECODER_COUNT_MASK GENMASK(3, 0) > +#define CXL_HDM_DECODER_TARGET_COUNT_MASK GENMASK(7, 4) > +#define CXL_HDM_DECODER0_BASE_LOW_OFFSET 0x10 > +#define CXL_HDM_DECODER0_BASE_HIGH_OFFSET 0x14 > +#define CXL_HDM_DECODER0_SIZE_LOW_OFFSET 0x18 > +#define CXL_HDM_DECODER0_SIZE_HIGH_OFFSET 0x1c > +#define CXL_HDM_DECODER0_CTRL_OFFSET 0x20 > + > /* CXL 2.0 8.2.8.1 Device Capabilities Array Register */ > #define CXLDEV_CAP_ARRAY_OFFSET 0x0 > #define CXLDEV_CAP_ARRAY_CAP_ID 0 > @@ -34,18 +59,30 @@ > #define CXLDEV_MBOX_BG_CMD_STATUS_OFFSET 0x18 > #define CXLDEV_MBOX_PAYLOAD_OFFSET 0x20 > > -/* > - * CXL_DEVICE_REGS - Common set of CXL Device register block base pointers > - * @status: CXL 2.0 8.2.8.3 Device Status Registers > - * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers > - * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers > - */ > +#define CXL_COMPONENT_REGS() \ > + void __iomem *hdm_decoder > + > #define CXL_DEVICE_REGS() \ > void __iomem *status; \ > void __iomem *mbox; \ > void __iomem *memdev > > /* See note for 'struct cxl_regs' for the rationale of this organization */ > +/* > + * CXL_COMPONENT_REGS - Common set of CXL Component register block base pointers > + * @hdm_decoder: CXL 2.0 8.2.5.12 CXL HDM Decoder Capability Structure > + */ > +struct cxl_component_regs { > + CXL_COMPONENT_REGS(); > +}; > + > +/* See note for 'struct cxl_regs' for the rationale of this organization */ > +/* > + * CXL_DEVICE_REGS - Common set of CXL Device register block base pointers > + * @status: CXL 2.0 8.2.8.3 Device Status Registers > + * @mbox: CXL 2.0 8.2.8.4 Mailbox Registers > + * @memdev: CXL 2.0 8.2.8.5 Memory Device Registers > + */ > struct cxl_device_regs { > CXL_DEVICE_REGS(); > }; > @@ -56,6 +93,12 @@ struct cxl_device_regs { > * agnostic code to include the prefix. > */ > struct cxl_regs { > + union { > + struct { > + CXL_COMPONENT_REGS(); > + }; > + struct cxl_component_regs component; > + }; > union { > struct { > CXL_DEVICE_REGS(); > @@ -70,6 +113,10 @@ struct cxl_reg_map { > unsigned long size; > }; > > +struct cxl_component_reg_map { > + struct cxl_reg_map hdm_decoder; > +}; > + > struct cxl_device_reg_map { > struct cxl_reg_map status; > struct cxl_reg_map mbox; > @@ -82,12 +129,18 @@ struct cxl_register_map { > u8 reg_type; > u8 barno; > union { > + struct cxl_component_reg_map component_map; > struct cxl_device_reg_map device_map; > }; > }; > > +void cxl_probe_component_regs(struct device *dev, void __iomem *base, > + struct cxl_component_reg_map *map); > void cxl_probe_device_regs(struct device *dev, void __iomem *base, > struct cxl_device_reg_map *map); > +int cxl_map_component_regs(struct pci_dev *pdev, > + struct cxl_component_regs *regs, > + struct cxl_register_map *map); > int cxl_map_device_regs(struct pci_dev *pdev, > struct cxl_device_regs *regs, > struct cxl_register_map *map); > diff --git a/drivers/cxl/pci.c b/drivers/cxl/pci.c > index 776cb8e28c2d..bf16328c6992 100644 > --- a/drivers/cxl/pci.c > +++ b/drivers/cxl/pci.c > @@ -982,9 +982,20 @@ static int cxl_probe_regs(struct cxl_mem *cxlm, void __iomem *base, > { > struct pci_dev *pdev = cxlm->pdev; > struct device *dev = &pdev->dev; > + struct cxl_component_reg_map *comp_map; > struct cxl_device_reg_map *dev_map; > > switch (map->reg_type) { > + case CXL_REGLOC_RBI_COMPONENT: > + comp_map = &map->component_map; > + cxl_probe_component_regs(dev, base, comp_map); > + if (!comp_map->hdm_decoder.valid) { > + dev_err(dev, "HDM decoder registers not found\n"); > + return -ENXIO; > + } > + > + dev_dbg(dev, "Set up component registers\n"); > + break; > case CXL_REGLOC_RBI_MEMDEV: > dev_map = &map->device_map; > cxl_probe_device_regs(dev, base, dev_map); > @@ -1012,6 +1023,10 @@ static int cxl_map_regs(struct cxl_mem *cxlm, struct cxl_register_map *map) > struct device *dev = &pdev->dev; > > switch (map->reg_type) { > + case CXL_REGLOC_RBI_COMPONENT: > + cxl_map_component_regs(pdev, &cxlm->regs.component, map); > + dev_dbg(dev, "Mapping component registers...\n"); > + break; > case CXL_REGLOC_RBI_MEMDEV: > cxl_map_device_regs(pdev, &cxlm->regs.device_regs, map); > dev_dbg(dev, "Probing device registers...\n"); > diff --git a/drivers/cxl/pci.h b/drivers/cxl/pci.h > index af3ec078cf6c..8b8c6afbe605 100644 > --- a/drivers/cxl/pci.h > +++ b/drivers/cxl/pci.h > @@ -25,6 +25,7 @@ > #define CXL_REGLOC_RBI_COMPONENT 1 > #define CXL_REGLOC_RBI_VIRT 2 > #define CXL_REGLOC_RBI_MEMDEV 3 > +#define CXL_REGLOC_RBI_MAX CXL_REGLOC_RBI_MEMDEV This doesn't seem to be used. > > #define CXL_REGLOC_ADDR_MASK GENMASK(31, 16) >