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From: Stanislav Spassov <stanspas@amazon.com>
To: <linux-pci@vger.kernel.org>
Cc: "Stanislav Spassov" <stanspas@amazon.de>,
	"Bjorn Helgaas" <bhelgaas@google.com>,
	"Thomas Gleixner" <tglx@linutronix.de>,
	"Andrew Morton" <akpm@linux-foundation.org>,
	"Jan H . Schönherr" <jschoenh@amazon.de>,
	"Jonathan Corbet" <corbet@lwn.net>,
	"Ashok Raj" <ashok.raj@intel.com>,
	"Alex Williamson" <alex.williamson@redhat.com>,
	"Sinan Kaya" <okaya@kernel.org>,
	"Rajat Jain" <rajatja@google.com>
Subject: [PATCH v2 09/17] PCI: Generalize pci_bus_max_d3cold_delay to pci_bus_max_delay
Date: Mon, 2 Mar 2020 19:44:21 +0100	[thread overview]
Message-ID: <20200302184429.12880-10-stanspas@amazon.com> (raw)
In-Reply-To: <20200302184429.12880-1-stanspas@amazon.com>

From: Stanislav Spassov <stanspas@amazon.de>

This allows determining the maximum of any of the several delay values
stored in struct pci_dev.

Signed-off-by: Stanislav Spassov <stanspas@amazon.de>
---
 drivers/pci/pci.c | 23 +++++++++++++++--------
 1 file changed, 15 insertions(+), 8 deletions(-)

diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index ba54164652cc..e4840dbf2d1c 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -4669,21 +4669,26 @@ bool pcie_wait_for_link(struct pci_dev *pdev, bool active)
 }
 
 /*
- * Find maximum D3cold delay required by all the devices on the bus.  The
- * spec says 100 ms, but firmware can lower it and we allow drivers to
- * increase it as well.
+ * Find maximum delay required by all the devices on the bus after the
+ * given initialization event.
  *
  * Called with @pci_bus_sem locked for reading.
+ *
+ * XXX: It is not clear if this should descend down across bridges (if any)
  */
-static int pci_bus_max_d3cold_delay(const struct pci_bus *bus)
+static int pci_bus_max_delay(const struct pci_bus *bus,
+			     enum pci_init_event event, int default_delay)
 {
 	const struct pci_dev *pdev;
-	int min_delay = 100;
+	int min_delay = default_delay;
 	int max_delay = 0;
 	int delay;
 
+	if (event >= PCI_INIT_EVENT_COUNT)
+		return default_delay;
+
 	list_for_each_entry(pdev, &bus->devices, bus_list) {
-		delay = pdev->delay[PCI_INIT_EVENT_RESET];
+		delay = pdev->delay[event];
 		if (delay < min_delay)
 			min_delay = delay;
 		if (delay > max_delay)
@@ -4728,11 +4733,13 @@ void pci_bridge_wait_for_secondary_bus(struct pci_dev *dev, bool sx_resume)
 		return;
 	}
 
-	/* Take d3cold_delay requirements into account */
+	/* Take delay requirements into account */
 	if (sx_resume && dev->ignore_reset_delay_on_sx_resume)
 		delay = 0;
 	else
-		delay = pci_bus_max_d3cold_delay(dev->subordinate);
+		delay = pci_bus_max_delay(dev->subordinate,
+					  PCI_INIT_EVENT_RESET,
+					  PCI_RESET_DELAY);
 
 	if (!delay) {
 		up_read(&pci_bus_sem);
-- 
2.25.1




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  parent reply	other threads:[~2020-03-02 18:46 UTC|newest]

Thread overview: 26+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-03-02 18:44 [PATCH v2 00/17] Improve PCI device post-reset readiness polling Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 01/17] PCI: Fall back to slot/bus reset if softer methods timeout Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 02/17] PCI: Remove unused PCI_PM_BUS_WAIT Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 03/17] PCI: Use pci_bridge_wait_for_secondary_bus after SBR Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 04/17] PCI: Do not override delay for D0->D3hot transition Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 05/17] PCI: Fix handling of _DSM 8 (avoiding reset delays) Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 06/17] PCI: Fix us->ms conversion in pci_acpi_optimize_delay Stanislav Spassov
2020-03-03  4:19   ` kbuild test robot
2020-03-03  4:19     ` kbuild test robot
2020-03-03  5:54   ` kbuild test robot
2020-03-03  5:54     ` kbuild test robot
2020-03-02 18:44 ` [PATCH v2 07/17] PCI: Clean up and document PM/reset delays Stanislav Spassov
2020-03-03  1:51   ` kbuild test robot
2020-03-03  1:51     ` kbuild test robot
2020-03-03  2:54   ` kbuild test robot
2020-03-03  2:54     ` kbuild test robot
2020-03-02 18:44 ` [PATCH v2 08/17] PCI: Add more delay overrides to struct pci_dev Stanislav Spassov
2020-03-02 18:44 ` Stanislav Spassov [this message]
2020-03-02 18:44 ` [PATCH v2 10/17] PCI: Use correct delay in pci_bridge_wait_for_secondary_bus Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 11/17] PCI: Refactor pci_dev_wait to remove timeout parameter Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 12/17] PCI: Refactor pci_dev_wait to take pci_init_event Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 13/17] PCI: Cache CRS Software Visibiliy in struct pci_dev Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 14/17] PCI: Introduce per-device reset_ready_poll override Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 15/17] PCI: Refactor polling loop out of pci_dev_wait Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 16/17] PCI: Add CRS handling to pci_dev_wait() Stanislav Spassov
2020-03-02 18:44 ` [PATCH v2 17/17] PCI: Lower PCIE_RESET_READY_POLL_MS from 1m to 1s Stanislav Spassov

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