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=-16.4 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 D49A9C433E6 for ; Mon, 1 Feb 2021 22:40:22 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 94B2064EBB for ; Mon, 1 Feb 2021 22:40:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229949AbhBAWkH (ORCPT ); Mon, 1 Feb 2021 17:40:07 -0500 Received: from mail.kernel.org ([198.145.29.99]:60446 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229515AbhBAWkD (ORCPT ); Mon, 1 Feb 2021 17:40:03 -0500 Received: by mail.kernel.org (Postfix) with ESMTPSA id 5550E64E8F; Mon, 1 Feb 2021 22:39:22 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1612219162; bh=T2g/GTyEcuYjTJ5eWuea1SGLvu0fFatPOt4eo14KckM=; h=Date:From:To:Cc:Subject:In-Reply-To:From; b=r6LolERSsiJR42kxMxKGo/fI/DYcNEcfAFG7i7J2f7/pjpZTFol4/5a0vauZIujwg EDGio/5OVjuKAstu7I6iyl6h0wLfog2m9ABVQMVWiwwrGagNE+OCLK8j4w1Dgt19jE A/rflOt5eptwn2dYGMFGoL9om9XhQxgmSdGxk3ykKqQ8EjvWwe36RTRB1bKKLdOajO hYtAQve+YKXUhc5rErqdgtIqMPIKh1EkB7q8wsU6ZA3Sry8ie5VY/5FlA2N0r6JmFh 7SfhfFEqEwJQ7pT+KV48A0Fb35upTmjuUQP3XlvA3I1xx9aK5lTxO6nXZ5ion8vkfy IKawbJLZE7yPw== Date: Mon, 1 Feb 2021 16:39:20 -0600 From: Bjorn Helgaas To: Gustavo Pimentel Cc: Bjorn Helgaas , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, Vinod Koul , Dan Williams , dmaengine@vger.kernel.org Subject: Re: [PATCH 04/15] PCI: Add pci_find_vsec_capability() to find a specific VSEC Message-ID: <20210201223920.GA46282@bjorn-Precision-5520> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org [+cc Vinod, Dan, dmaengine] On Tue, Dec 15, 2020 at 06:30:13PM +0100, Gustavo Pimentel wrote: > Add pci_find_vsec_capability() that crawls through the device config > space searching in all Vendor-Specific Extended Capabilities for a > particular capability ID. > > Vendor-Specific Extended Capability (VSEC) is a PCIe capability (acts > like a wrapper) specified by PCI-SIG that allows the vendor to create > their own and specific capability in the device config space. > > Signed-off-by: Gustavo Pimentel If you fix the below, feel free to add my Acked-by: Bjorn Helgaas Otherwise, I can take it myself. But that will be an ordering issue in the merge window if you merge the rest of the series via another tree. > --- > drivers/pci/pci.c | 29 +++++++++++++++++++++++++++++ > include/linux/pci.h | 1 + > include/uapi/linux/pci_regs.h | 5 +++++ > 3 files changed, 35 insertions(+) > > diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c > index 6d4d5a2..235d0b2 100644 > --- a/drivers/pci/pci.c > +++ b/drivers/pci/pci.c > @@ -623,6 +623,35 @@ u64 pci_get_dsn(struct pci_dev *dev) > } > EXPORT_SYMBOL_GPL(pci_get_dsn); > > +/** > + * pci_find_vsec_capability - Find a vendor-specific extended capability > + * @dev: PCI device to query > + * @cap: vendor-specific capability id code s/id/ID/ > + * > + * Returns the address of the vendor-specific structure that matches the > + * requested capability id code within the device's PCI configuration space s/id/ID/ > + * or 0 if it does not find a match. > + */ > +int pci_find_vsec_capability(struct pci_dev *dev, int vsec_cap_id) > +{ > + u32 header; > + int vsec; int vsec; u32 header; since that's the order they're used. > + > + vsec = pci_find_ext_capability(dev, PCI_EXT_CAP_ID_VNDR); > + while (vsec) { > + if (pci_read_config_dword(dev, vsec + 0x4, s/0x4/PCI_VSEC_HDR/ > + &header) == PCIBIOS_SUCCESSFUL && > + PCI_VSEC_CAP_ID(header) == vsec_cap_id) > + break; return vsec; > + > + vsec = pci_find_next_ext_capability(dev, vsec, > + PCI_EXT_CAP_ID_VNDR); > + } > + > + return vsec; return 0; > +} > +EXPORT_SYMBOL_GPL(pci_find_vsec_capability); > + > static int __pci_find_next_ht_cap(struct pci_dev *dev, int pos, int ht_cap) > { > int rc, ttl = PCI_FIND_CAP_TTL; > diff --git a/include/linux/pci.h b/include/linux/pci.h > index 22207a7..effecb0 100644 > --- a/include/linux/pci.h > +++ b/include/linux/pci.h > @@ -1067,6 +1067,7 @@ int pci_find_capability(struct pci_dev *dev, int cap); > int pci_find_next_capability(struct pci_dev *dev, u8 pos, int cap); > int pci_find_ext_capability(struct pci_dev *dev, int cap); > int pci_find_next_ext_capability(struct pci_dev *dev, int pos, int cap); > +int pci_find_vsec_capability(struct pci_dev *dev, int vsec_cap_id); > int pci_find_ht_capability(struct pci_dev *dev, int ht_cap); > int pci_find_next_ht_capability(struct pci_dev *dev, int pos, int ht_cap); > struct pci_bus *pci_find_next_bus(const struct pci_bus *from); > diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h > index a95d55f..f5d17be 100644 > --- a/include/uapi/linux/pci_regs.h > +++ b/include/uapi/linux/pci_regs.h > @@ -730,6 +730,11 @@ > #define PCI_EXT_CAP_DSN_SIZEOF 12 > #define PCI_EXT_CAP_MCAST_ENDPOINT_SIZEOF 40 > > +/* Vendor-Specific Extended Capabilities */ > +#define PCI_VSEC_CAP_ID(header) (header & 0x0000ffff) > +#define PCI_VSEC_CAP_REV(header) ((header >> 16) & 0xf) > +#define PCI_VSEC_CAP_LEN(header) ((header >> 20) & 0xffc) Please put these next to the existing PCI_VSEC_HDR. Why does PCI_VSEC_CAP_LEN mask with 0xffc instead of 0xfff? I don't see anything in the spec about VSEC Length having to be a multiple of 4 (PCIe r5.0, sec 7.9.5.2). But you don't use this anyway, so I'd just drop it (and PCI_VSEC_CAP_REV) altogether. > /* Advanced Error Reporting */ > #define PCI_ERR_UNCOR_STATUS 4 /* Uncorrectable Error Status */ > #define PCI_ERR_UNC_UND 0x00000001 /* Undefined */ > -- > 2.7.4 >