[RTEMS Project] #3062: When a PCI addreess range is empty PCI Library Programs Bridges with errouneous address range

[RTEMS trac]

#3062: When a PCI addreess range is empty PCI Library Programs Bridges with
errouneous address range
--------------------------+-------------------------------
 Reporter:  Jeffrey Hill  |       Owner:  Daniel Hellstrom
     Type:  defect        |      Status:  assigned
 Priority:  normal        |   Milestone:
Component:  cpukit        |     Version:  4.11
 Severity:  normal        |  Resolution:
 Keywords:                |
--------------------------+-------------------------------

Comment (by Jeffrey Hill):

 At line 309 the memory and IO spaces are initially disabled when the
 device or bridge is located.
 {{{
     PCI_CFG_W16(pcidev, PCIR_COMMAND, 0);
 }}}
 At Line 342 the bridge's 64 bit memory and memory IO space base addresses
 are cleared to zero when the bridge device is initially located
 {{{
     PCI_CFG_W32(pcidev, 0x28, 0);
     PCI_CFG_W32(pcidev, 0x2C, 0);
 }}}

 However, I don't see that registers 0x1c, 0x20, and 0x24 are receiving
 initialization in pci_find_devs, and therefore they will need to be set
 later

 And therefore my suggested change below isn’t going to perform the
 necessary initialization for the unused address spaces in a bridge.
 {{{
 @@ -703,47 +707,49 @@ static void pci_set_bar(struct pci_dev *dev, int
 residx)
         if ((res->flags == 0) || (res->flags & PCI_RES_FAIL))
                 return;

 +  if ( res->end <= res->start )
 +               return;
 +
 }}}

 I will need to watch it run again and verify that res->end and res->start
 are actually being used when there values are both zero, as I fear

--
Ticket URL: <http://devel.rtems.org/ticket/3062#comment:11>
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