[PATCH V2 7/7] PCI: make reset poll time adjustable

From: Sinan Kaya
Date: Mon Nov 27 2017 - 01:20:58 EST


Introduce pci=resetpolltime= argument to override 60 seconds poll time in
units of milliseconds.

Signed-off-by: Sinan Kaya <okaya@xxxxxxxxxxxxxx>
---
Documentation/admin-guide/kernel-parameters.txt | 2 ++
drivers/pci/pci.c | 13 ++++++++-----
2 files changed, 10 insertions(+), 5 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 0549662..a07d4f5 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -3071,6 +3071,8 @@
pcie_scan_all Scan all possible PCIe devices. Otherwise we
only look for one device below a PCIe downstream
port.
+ resetpolltime= Adjusts the default poll time following hot reset
+ and D3->D0 transition.

pcie_aspm= [PCIE] Forcibly enable or disable PCIe Active State Power
Management.
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 8472c24..a6c3e25 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -127,7 +127,7 @@ static int __init pcie_port_pm_setup(char *str)

/* time to wait after a reset for device to become responsive */
#define PCIE_RESET_READY_POLL_MS 60000
-
+static unsigned long pci_reset_polltime = PCIE_RESET_READY_POLL_MS;
/**
* pci_bus_max_busnr - returns maximum PCI bus number of given bus' children
* @bus: pointer to PCI bus structure to search
@@ -3904,7 +3904,7 @@ int pcie_flr(struct pci_dev *dev)
*/
msleep(100);

- return pci_dev_wait(dev, "FLR", PCIE_RESET_READY_POLL_MS);
+ return pci_dev_wait(dev, "FLR", pci_reset_polltime);
}
EXPORT_SYMBOL_GPL(pcie_flr);

@@ -3945,7 +3945,7 @@ static int pci_af_flr(struct pci_dev *dev, int probe)
*/
msleep(100);

- return pci_dev_wait(dev, "AF_FLR", PCIE_RESET_READY_POLL_MS);
+ return pci_dev_wait(dev, "AF_FLR", pci_reset_polltime);
}

/**
@@ -3990,7 +3990,7 @@ static int pci_pm_reset(struct pci_dev *dev, int probe)
pci_write_config_word(dev, dev->pm_cap + PCI_PM_CTRL, csr);
pci_dev_d3_sleep(dev);

- return pci_dev_wait(dev, "PM D3->D0", PCIE_RESET_READY_POLL_MS);
+ return pci_dev_wait(dev, "PM D3->D0", pci_reset_polltime);
}

void pci_reset_secondary_bus(struct pci_dev *dev)
@@ -4035,7 +4035,7 @@ int pci_reset_bridge_secondary_bus(struct pci_dev *dev)
{
pcibios_reset_secondary_bus(dev);

- return pci_dev_wait(dev, "bus reset", PCIE_RESET_READY_POLL_MS);
+ return pci_dev_wait(dev, "bus reset", pci_reset_polltime);
}
EXPORT_SYMBOL_GPL(pci_reset_bridge_secondary_bus);

@@ -5528,6 +5528,9 @@ static int __init pci_setup(char *str)
pcie_bus_config = PCIE_BUS_PEER2PEER;
} else if (!strncmp(str, "pcie_scan_all", 13)) {
pci_add_flags(PCI_SCAN_ALL_PCIE_DEVS);
+ } else if (!strncmp(str, "resetpolltime=", 14)) {
+ pci_reset_polltime =
+ simple_strtoul(str + 14, &str, 0);
} else {
printk(KERN_ERR "PCI: Unknown option `%s'\n",
str);
--
1.9.1