On Wed, Sep 02, 2020 at 03:19:55PM +1000, Jonathan Gray wrote:
> On Tue, Sep 01, 2020 at 11:44:03PM -0500, Jordan Hargrave wrote:
> > This patch adds a common function for scanning PCIE Express Capability list
> > The PCIE Capability list starts at 0x100 in extended PCI configuration 
> > space.
> 
> This seems to only handle extended capabilities?
> Something like pcie_get_ext_capability() would be a better name.
> 
> It is 'PCI Express' not 'PCIExpress'
> 
> 'ofs & 3' test doesn't make sense when PCI_PCIE_ECAP_NEXT() always
> masks those bits.
>

  Ok fixed below...
  
> > 
> > ---
> >  sys/dev/pci/pci.c    | 28 ++++++++++++++++++++++++++++
> >  sys/dev/pci/pcivar.h |  2 ++
> >  2 files changed, 30 insertions(+)
> > 
> > diff --git a/sys/dev/pci/pci.c b/sys/dev/pci/pci.c
> > index bf75f875e..8f9a5ef7a 100644
> > --- a/sys/dev/pci/pci.c
> > +++ b/sys/dev/pci/pci.c
> > @@ -677,6 +677,34 @@ pci_get_ht_capability(pci_chipset_tag_t pc, pcitag_t 
> > tag, int capid,
> >     return (0);
> >  }
> >  
> > +int
> > +pcie_get_capability(pci_chipset_tag_t pc, pcitag_t tag, int capid,
> > +    int *offset, pcireg_t *value)
> > +{
> > +   pcireg_t reg;
> > +   unsigned int ofs;
> > +
> > +   /* Make sure we support PCIExpress device */
> > +   if (pci_get_capability(pc, tag, PCI_CAP_PCIEXPRESS, NULL, NULL) == 0)
> > +           return (0);
> > +   /* Scan PCIExpress capabilities */
> > +   ofs = PCI_PCIE_ECAP;
> > +   while (ofs != 0) {
> > +           if ((ofs & 3) || (ofs < PCI_PCIE_ECAP))
> > +                   return (0);
> > +           reg = pci_conf_read(pc, tag, ofs);
> > +           if (PCI_PCIE_ECAP_ID(reg) == capid) {
> > +                   if (offset)
> > +                           *offset = ofs;
> > +                   if (value)
> > +                           *value = reg;
> > +                   return (1);
> > +           }
> > +           ofs = PCI_PCIE_ECAP_NEXT(reg);
> > +   }
> > +   return (0);
> > +}
> > +
> >  uint16_t
> >  pci_requester_id(pci_chipset_tag_t pc, pcitag_t tag)
> >  {
> > diff --git a/sys/dev/pci/pcivar.h b/sys/dev/pci/pcivar.h
> > index bdfe0404f..0376ba992 100644
> > --- a/sys/dev/pci/pcivar.h
> > +++ b/sys/dev/pci/pcivar.h
> > @@ -233,6 +233,8 @@ int     pci_io_find(pci_chipset_tag_t, pcitag_t, int, 
> > bus_addr_t *,
> >  int        pci_mem_find(pci_chipset_tag_t, pcitag_t, int, bus_addr_t *,
> >         bus_size_t *, int *);
> >  
> > +int        pcie_get_capability(pci_chipset_tag_t, pcitag_t, int,
> > +       int *, pcireg_t *);
> >  int        pci_get_capability(pci_chipset_tag_t, pcitag_t, int,
> >         int *, pcireg_t *);
> >  int        pci_get_ht_capability(pci_chipset_tag_t, pcitag_t, int,
> > -- 
> > 2.26.2
> > 
> > 
diff --git a/sys/dev/pci/pci.c b/sys/dev/pci/pci.c
index bf75f875e..56a85453a 100644
--- a/sys/dev/pci/pci.c
+++ b/sys/dev/pci/pci.c
@@ -677,6 +677,34 @@ pci_get_ht_capability(pci_chipset_tag_t pc, pcitag_t tag, 
int capid,
        return (0);
 }
 
+int
+pci_get_ext_capability(pci_chipset_tag_t pc, pcitag_t tag, int capid,
+    int *offset, pcireg_t *value)
+{
+       pcireg_t reg;
+       unsigned int ofs;
+
+       /* Make sure we support PCI Express device */
+       if (pci_get_capability(pc, tag, PCI_CAP_PCIEXPRESS, NULL, NULL) == 0)
+               return (0);
+       /* Scan PCI Express capabilities */
+       ofs = PCI_PCIE_ECAP;
+       while (ofs != 0) {
+               if (ofs < PCI_PCIE_ECAP)
+                       return (0);
+               reg = pci_conf_read(pc, tag, ofs);
+               if (PCI_PCIE_ECAP_ID(reg) == capid) {
+                       if (offset)
+                               *offset = ofs;
+                       if (value)
+                               *value = reg;
+                       return (1);
+               }
+               ofs = PCI_PCIE_ECAP_NEXT(reg);
+       }
+       return (0);
+}
+
 uint16_t
 pci_requester_id(pci_chipset_tag_t pc, pcitag_t tag)
 {
diff --git a/sys/dev/pci/pcivar.h b/sys/dev/pci/pcivar.h
index bdfe0404f..1a19996f5 100644
--- a/sys/dev/pci/pcivar.h
+++ b/sys/dev/pci/pcivar.h
@@ -237,6 +237,8 @@ int pci_get_capability(pci_chipset_tag_t, pcitag_t, int,
            int *, pcireg_t *);
 int    pci_get_ht_capability(pci_chipset_tag_t, pcitag_t, int,
            int *, pcireg_t *);
+int    pci_get_ext_capability(pci_chipset_tag_t, pcitag_t, int,
+           int *, pcireg_t *);
 
 struct msix_vector;
 

Reply via email to