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| author | Sinan Kaya <okaya@codeaurora.org> | 2017-08-29 14:45:44 -0500 |
|---|---|---|
| committer | Bjorn Helgaas <bhelgaas@google.com> | 2017-08-29 14:45:44 -0500 |
| commit | 62bc6a6f7468bc6d6cb39177504e79df401aea76 (patch) | |
| tree | 0d53c180be8a502c7f8d0db3d23184346b37d162 /drivers/pci/probe.c | |
| parent | 9f98275671a58516f87b7eb02a3497635861930a (diff) | |
| download | linux-rt-62bc6a6f7468bc6d6cb39177504e79df401aea76.tar.gz | |
PCI: Add pci_bus_crs_vendor_id() to detect CRS response data
Add pci_bus_crs_vendor_id() to determine whether data returned for a config
read of the Vendor ID indicates a Configuration Request Retry Status (CRS)
response.
Per PCIe r3.1, sec 2.3.2, this data is only returned if:
- CRS Software Visibility is enabled,
- a config read includes both bytes of the Vendor ID, and
- the read receives a CRS completion
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
[bhelgaas: changelog, change name to pci_bus_crs_vendor_id(), make static
in probe.c, use it in pci_bus_read_dev_vendor_id()]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Diffstat (limited to 'drivers/pci/probe.c')
| -rw-r--r-- | drivers/pci/probe.c | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c index 150093817c59..5e001bbc2392 100644 --- a/drivers/pci/probe.c +++ b/drivers/pci/probe.c @@ -1853,6 +1853,11 @@ struct pci_dev *pci_alloc_dev(struct pci_bus *bus) } EXPORT_SYMBOL(pci_alloc_dev); +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) { @@ -1872,7 +1877,7 @@ bool pci_bus_read_dev_vendor_id(struct pci_bus *bus, int devfn, u32 *l, * by the PCIe spec. Ignore the device ID and only check for * (vendor id == 1). */ - while ((*l & 0xffff) == 0x0001) { + while (pci_bus_crs_vendor_id(*l)) { if (!crs_timeout) return false; |