From patchwork Wed Oct 9 20:05:21 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: stuart hayes X-Patchwork-Id: 11182043 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id CEA2A14ED for ; Wed, 9 Oct 2019 20:05:36 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 9FE202190F for ; Wed, 9 Oct 2019 20:05:36 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="nW5uqekj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1731397AbfJIUFf (ORCPT ); Wed, 9 Oct 2019 16:05:35 -0400 Received: from mail-ot1-f68.google.com ([209.85.210.68]:40204 "EHLO mail-ot1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728804AbfJIUFd (ORCPT ); Wed, 9 Oct 2019 16:05:33 -0400 Received: by mail-ot1-f68.google.com with SMTP id y39so2824285ota.7; Wed, 09 Oct 2019 13:05:33 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:in-reply-to:references; bh=r5z1PSBgdgyQOytDnCk9ConnRnIEa9FCO7qAX4IBOjg=; b=nW5uqekjnVCwaOAn53as+jJbYKXf1215vQ6bDEYRlNR06ISI0A/xz/Ca+2kx1URXjs ba7Onb/y/XpcQz48a8DgrjyZ3xdHMclaY3dKw9/cjNfjb13F3dovOLrOsGsfJVGYJWcD pVXlOP6DTfpolDGlYuY0GwrVJtHd6AUsUZ7kCNmYXabpOZHRD19uYguLZvcG38v5IsV9 sm3OXePYPH9Ur6F0aBmJppQKsoMu7q4BCkEulG2rEfErrgtr+03xK28sKNHNXb9BIZsM wrDWSfv6QHbK4Rn8lfy8/AeDpt9JRXEd5QoASn0DliTwTz+6Y5qMk6LlHKGnQEEiVe95 AAvw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references; bh=r5z1PSBgdgyQOytDnCk9ConnRnIEa9FCO7qAX4IBOjg=; b=MYr4XCMDH6VTAnqdek0teUal2PWKt1qVkJ+F2SunQEVZH1OGCHJrnoPKwAFLkV05F6 NzKye5RGlfxW2VNe1Q+P6gcSwHKe2g5o389k+WrMoOCr654fPpTvTr0ygCol86oiXCYL sE4KdHpBTJpG/YGUMnotVjLwAb31Tokt0/5W40HpzuapM6Li7yAHt+X+b66kxJAIBD0/ mkyTt+m1zVjc+mahhIFD1LuWxWzIMH353f/G9lzryKTQIGJ9Rc5s4rRGlaPgZ9Ow4SAK LHdBtxsvfA3agfiXdbjwfTr/anLYaCdYpwZrw/NoLP3/Pkubef5f7GyuHRlmh0sqY0Fw 1Nag== X-Gm-Message-State: APjAAAXgwjMDNgQ7iAvcJHxLNy/KXA+wtaZdkdY0W1ZdCrhRnieqqrr8 mBfFV9El4R4vVVnNZcocNcw= X-Google-Smtp-Source: APXvYqxneQvrhHl9r9dkG0qDmr02zqr41ae9tsZ7LdANEKWgISkTN8P89x3xZaVQtXxVUHlKA1tgzQ== X-Received: by 2002:a05:6830:1be3:: with SMTP id k3mr4703396otb.180.1570651532778; Wed, 09 Oct 2019 13:05:32 -0700 (PDT) Received: from localhost.localdomain ([143.166.81.254]) by smtp.gmail.com with ESMTPSA id b5sm976883oia.20.2019.10.09.13.05.31 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 09 Oct 2019 13:05:32 -0700 (PDT) From: Stuart Hayes To: Bjorn Helgaas Cc: Austin Bolen , keith.busch@intel.com, Alexandru Gagniuc , "Rafael J . Wysocki" , Mika Westerberg , Andy Shevchenko , "Gustavo A . R . Silva" , Sinan Kaya , Oza Pawandeep , linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org, lukas@wunner.de Subject: [PATCH 1/3] PCI: pciehp: Add support for disabling in-band presence Date: Wed, 9 Oct 2019 16:05:21 -0400 Message-Id: <20191009200523.8436-2-stuart.w.hayes@gmail.com> X-Mailer: git-send-email 2.18.1 In-Reply-To: <20191009200523.8436-1-stuart.w.hayes@gmail.com> References: <20191009200523.8436-1-stuart.w.hayes@gmail.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org From: Alexandru Gagniuc The presence detect state (PDS) is normally a logical or of in-band and out-of-band presence. As of PCIe 4.0, there is the option to disable in-band presence so that the PDS bit always reflects the state of the out-of-band presence. The recommendation of the PCIe spec is to disable in-band presence whenever supported. Signed-off-by: Alexandru Gagniuc --- drivers/pci/hotplug/pciehp.h | 1 + drivers/pci/hotplug/pciehp_hpc.c | 9 ++++++++- include/uapi/linux/pci_regs.h | 2 ++ 3 files changed, 11 insertions(+), 1 deletion(-) diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h index 654c972b8ea0..27e4cd6529b0 100644 --- a/drivers/pci/hotplug/pciehp.h +++ b/drivers/pci/hotplug/pciehp.h @@ -83,6 +83,7 @@ struct controller { struct pcie_device *pcie; u32 slot_cap; /* capabilities and quirks */ + unsigned int inband_presence_disabled:1; u16 slot_ctrl; /* control register access */ struct mutex ctrl_lock; diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c index 1a522c1c4177..dc109d521f30 100644 --- a/drivers/pci/hotplug/pciehp_hpc.c +++ b/drivers/pci/hotplug/pciehp_hpc.c @@ -811,7 +811,7 @@ static inline void dbg_ctrl(struct controller *ctrl) struct controller *pcie_init(struct pcie_device *dev) { struct controller *ctrl; - u32 slot_cap, link_cap; + u32 slot_cap, slot_cap2, link_cap; u8 poweron; struct pci_dev *pdev = dev->port; struct pci_bus *subordinate = pdev->subordinate; @@ -869,6 +869,13 @@ struct controller *pcie_init(struct pcie_device *dev) FLAG(link_cap, PCI_EXP_LNKCAP_DLLLARC), pdev->broken_cmd_compl ? " (with Cmd Compl erratum)" : ""); + pcie_capability_read_dword(pdev, PCI_EXP_SLTCAP2, &slot_cap2); + if (slot_cap2 & PCI_EXP_SLTCAP2_IBPD) { + pcie_write_cmd_nowait(ctrl, PCI_EXP_SLTCTL_IBPD_DISABLE, + PCI_EXP_SLTCTL_IBPD_DISABLE); + ctrl->inband_presence_disabled = 1; + } + /* * If empty slot's power status is on, turn power off. The IRQ isn't * requested yet, so avoid triggering a notification with this command. diff --git a/include/uapi/linux/pci_regs.h b/include/uapi/linux/pci_regs.h index 29d6e93fd15e..ea1cf9546e4d 100644 --- a/include/uapi/linux/pci_regs.h +++ b/include/uapi/linux/pci_regs.h @@ -604,6 +604,7 @@ #define PCI_EXP_SLTCTL_PWR_OFF 0x0400 /* Power Off */ #define PCI_EXP_SLTCTL_EIC 0x0800 /* Electromechanical Interlock Control */ #define PCI_EXP_SLTCTL_DLLSCE 0x1000 /* Data Link Layer State Changed Enable */ +#define PCI_EXP_SLTCTL_IBPD_DISABLE 0x4000 /* In-band PD disable */ #define PCI_EXP_SLTSTA 26 /* Slot Status */ #define PCI_EXP_SLTSTA_ABP 0x0001 /* Attention Button Pressed */ #define PCI_EXP_SLTSTA_PFD 0x0002 /* Power Fault Detected */ @@ -676,6 +677,7 @@ #define PCI_EXP_LNKSTA2 50 /* Link Status 2 */ #define PCI_CAP_EXP_ENDPOINT_SIZEOF_V2 52 /* v2 endpoints with link end here */ #define PCI_EXP_SLTCAP2 52 /* Slot Capabilities 2 */ +#define PCI_EXP_SLTCAP2_IBPD 0x0001 /* In-band PD Disable Supported */ #define PCI_EXP_SLTCTL2 56 /* Slot Control 2 */ #define PCI_EXP_SLTSTA2 58 /* Slot Status 2 */