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Commit 6a802ef0 authored by Sinan Kaya's avatar Sinan Kaya Committed by Bjorn Helgaas
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PCI: Factor out pci_bus_wait_crs() 



Configuration Request Retry Status (CRS) was previously hidden inside
pci_bus_read_dev_vendor_id().  We want to add support for CRS in other
situations, such as waiting for a device to become ready after a Function
Level Reset.

Move CRS handling into pci_bus_wait_crs() so it can be called from other
places.

Signed-off-by: default avatarSinan Kaya <okaya@codeaurora.org>
[bhelgaas: pass pointer, not value, to pci_bus_wait_crs() so caller gets
correct Vendor ID]
Signed-off-by: default avatarBjorn Helgaas <bhelgaas@google.com>
parent 62bc6a6f

drivers/pci/probe.c

+27 −16
Original line number Diff line number Diff line
@@ -1858,30 +1858,24 @@ static bool pci_bus_crs_vendor_id(u32 l) 
	return (l & 0xffff) == 0x0001;

}



bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,

				int crs_timeout)

static bool pci_bus_wait_crs(struct pci_bus *bus, int devfn, u32 *l,

			     int timeout)

{

	int delay = 1;



	if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))

		return false;

	if (!pci_bus_crs_vendor_id(*l))

		return true;	/* not a CRS completion */



	/* some broken boards return 0 or ~0 if a slot is empty: */

	if (*l == 0xffffffff || *l == 0x00000000 ||

	    *l == 0x0000ffff || *l == 0xffff0000)

		return false;

	if (!timeout)

		return false;	/* CRS, but caller doesn't want to wait */



	/*

	 * Configuration Request Retry Status.  Some root ports return the

	 * actual device ID instead of the synthetic ID (0xFFFF) required

	 * by the PCIe spec.  Ignore the device ID and only check for

	 * (vendor id == 1).

	 * We got the reserved Vendor ID that indicates a completion with

	 * Configuration Request Retry Status (CRS).  Retry until we get a

	 * valid Vendor ID or we time out.

	 */

	while (pci_bus_crs_vendor_id(*l)) {

		if (!crs_timeout)

			return false;



		if (delay > crs_timeout) {

		if (delay > timeout) {

			printk(KERN_WARNING "pci %04x:%02x:%02x.%d: not responding\n",

			       pci_domain_nr(bus), bus->number, PCI_SLOT(devfn),

			       PCI_FUNC(devfn));
@@ -1897,6 +1891,23 @@ bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, 


	return true;

}



bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l,

				int timeout)

{

	if (pci_bus_read_config_dword(bus, devfn, PCI_VENDOR_ID, l))

		return false;



	/* some broken boards return 0 or ~0 if a slot is empty: */

	if (*l == 0xffffffff || *l == 0x00000000 ||

	    *l == 0x0000ffff || *l == 0xffff0000)

		return false;



	if (pci_bus_crs_vendor_id(*l))

		return pci_bus_wait_crs(bus, devfn, l, timeout);



	return true;

}

EXPORT_SYMBOL(pci_bus_read_dev_vendor_id);



/*