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From: Oza Pawandeep <poza@codeaurora.org>
To: Bjorn Helgaas <bhelgaas@google.com>,
	Philippe Ombredanne <pombredanne@nexb.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Kate Stewart <kstewart@linuxfoundation.org>,
	linux-pci@vger.kernel.org, linux-kernel@vger.kernel.org,
	Dongdong Liu <liudongdong3@huawei.com>,
	Keith Busch <keith.busch@intel.com>, Wei Zhang <wzhang@fb.com>,
	Sinan Kaya <okaya@codeaurora.org>,
	Timur Tabi <timur@codeaurora.org>
Cc: Oza Pawandeep <poza@codeaurora.org>
Subject: [PATCH v12 5/6] PCI: Unify wait for link active into generic PCI
Date: Wed, 28 Feb 2018 22:34:16 +0530	[thread overview]
Message-ID: <1519837457-3596-6-git-send-email-poza@codeaurora.org> (raw)
In-Reply-To: <1519837457-3596-1-git-send-email-poza@codeaurora.org>

Clients such as HP, DPC are using pcie_wait_link_active(), which waits
till the link becomes active or inactive.

Made generic function and moved it to drivers/pci/pci.c

Signed-off-by: Oza Pawandeep <poza@codeaurora.org>

diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 18a42f8..e0c2b8e 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -231,25 +231,11 @@ bool pciehp_check_link_active(struct controller *ctrl)
 	return ret;
 }
 
-static void __pcie_wait_link_active(struct controller *ctrl, bool active)
-{
-	int timeout = 1000;
-
-	if (pciehp_check_link_active(ctrl) == active)
-		return;
-	while (timeout > 0) {
-		msleep(10);
-		timeout -= 10;
-		if (pciehp_check_link_active(ctrl) == active)
-			return;
-	}
-	ctrl_dbg(ctrl, "Data Link Layer Link Active not %s in 1000 msec\n",
-			active ? "set" : "cleared");
-}
-
 static void pcie_wait_link_active(struct controller *ctrl)
 {
-	__pcie_wait_link_active(ctrl, true);
+	struct pci_dev *pdev = ctrl_dev(ctrl);
+
+	pcie_wait_for_link(pdev, true);
 }
 
 static bool pci_bus_check_dev(struct pci_bus *bus, int devfn)
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index f6a4dd1..bbea997 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4176,6 +4176,35 @@ static int pci_pm_reset(struct pci_dev *dev, int probe)
 	return 0;
 }
 
+/**
+ * pcie_wait_for_link - Wait for link till it's active/inactive
+ * @pdev: Bridge device
+ * @active: waiting for active or inactive ?
+ *
+ * Use this to wait till link becomes active or inactive.
+ */
+bool pcie_wait_for_link(struct pci_dev *pdev, bool active)
+{
+	int timeout = 1000;
+	bool ret;
+	u16 lnk_status;
+
+	for (;;) {
+		pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
+		ret = !!(lnk_status & PCI_EXP_LNKSTA_DLLLA);
+		if (ret == active)
+			return true;
+		if (timeout <= 0)
+			break;
+		timeout -= 10;
+	}
+
+	pci_info(pdev, "Data Link Layer Link Active not %s in 1000 msec\n",
+		 active ? "set" : "cleared");
+
+	return false;
+}
+
 void pci_reset_secondary_bus(struct pci_dev *dev)
 {
 	u16 ctrl;
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index abc514e..5c44fbc 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -345,6 +345,8 @@ static inline resource_size_t pci_resource_alignment(struct pci_dev *dev,
 /* PCI error reporting and recovery */
 void pcie_do_recovery(struct pci_dev *dev, int severity);
 
+bool pcie_wait_for_link(struct pci_dev *pdev, bool active);
+
 #ifdef CONFIG_PCIEASPM
 void pcie_aspm_init_link_state(struct pci_dev *pdev);
 void pcie_aspm_exit_link_state(struct pci_dev *pdev);
diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c
index 517c8b4..8e1553b 100644
--- a/drivers/pci/pcie/pcie-dpc.c
+++ b/drivers/pci/pcie/pcie-dpc.c
@@ -95,19 +95,9 @@ static int dpc_wait_rp_inactive(struct dpc_dev *dpc)
 
 static void dpc_wait_link_inactive(struct dpc_dev *dpc)
 {
-	unsigned long timeout = jiffies + HZ;
 	struct pci_dev *pdev = dpc->dev->port;
-	struct device *dev = &dpc->dev->device;
-	u16 lnk_status;
 
-	pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
-	while (lnk_status & PCI_EXP_LNKSTA_DLLLA &&
-					!time_after(jiffies, timeout)) {
-		msleep(10);
-		pcie_capability_read_word(pdev, PCI_EXP_LNKSTA, &lnk_status);
-	}
-	if (lnk_status & PCI_EXP_LNKSTA_DLLLA)
-		dev_warn(dev, "Link state not disabled for DPC event\n");
+	pcie_wait_for_link(pdev, false);
 }
 
 /**
-- 
Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc.,
a Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.

  parent reply	other threads:[~2018-02-28 17:04 UTC|newest]

Thread overview: 25+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-02-28 17:04 [PATCH v12 0/6] Address error and recovery for AER and DPC Oza Pawandeep
2018-02-28 17:04 ` [PATCH v12 1/6] PCI/AER: Rename error recovery to generic PCI naming Oza Pawandeep
2018-02-28 17:04 ` [PATCH v12 2/6] PCI/AER: Factor out error reporting from AER Oza Pawandeep
2018-02-28 17:04 ` [PATCH v12 3/6] PCI/PORTDRV: Implement generic find service Oza Pawandeep
2018-03-06 14:02   ` Sinan Kaya
2018-03-08  7:56     ` poza
2018-02-28 17:04 ` [PATCH v12 4/6] PCI/DPC: Unify and plumb error handling into DPC Oza Pawandeep
2018-02-28 17:04 ` Oza Pawandeep [this message]
2018-02-28 17:04 ` [PATCH v12 6/6] PCI/DPC: Enumerate the devices after DPC trigger event Oza Pawandeep
2018-03-11 22:03 ` [PATCH v12 0/6] Address error and recovery for AER and DPC Bjorn Helgaas
2018-03-12  3:03   ` Sinan Kaya
2018-03-12 14:25     ` Keith Busch
2018-03-12 14:46       ` poza
2018-03-12 14:58         ` Keith Busch
2018-03-12 15:34           ` poza
2018-03-12 17:33             ` Keith Busch
2018-03-12 17:41               ` Sinan Kaya
2018-03-12 17:56                 ` Keith Busch
2018-03-12 19:47       ` Bjorn Helgaas
2018-03-12 23:26         ` Keith Busch
2018-03-13  3:47           ` Sinan Kaya
2018-03-14 20:50             ` Keith Busch
2018-03-14 21:00               ` Sinan Kaya
2018-05-08 19:25           ` Bjorn Helgaas
2018-03-12 14:01   ` poza

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