linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
* pci overmapping
@ 2013-05-02 17:05 Yoder Stuart-B08248
  2013-05-02 17:13 ` Scott Wood
  0 siblings, 1 reply; 5+ messages in thread
From: Yoder Stuart-B08248 @ 2013-05-02 17:05 UTC (permalink / raw)
  To: galak@kernel.crashing.org
  Cc: Sethi Varun-B16395, linuxppc-dev@lists.ozlabs.org

Kumar,

In fsl_pci.c there is a change you made a while back:
  "powerpc/fsl: Setup PCI inbound window based on actual amount of memory"

...and there is this comment in the code:

    /* PCIe can overmap inbound & outbound since RX & TX are separated */
    if (early_find_capability(hose, 0, 0, PCI_CAP_ID_EXP)) {

You are implying that PCIe can overmap and PCI can't.  Why is
that?   (I'm assuming that 'overmap' means that inbound window
can extend beyond the end of ram.)

We are facing an issue for a non-PCI express controller (i.e. without
PCI_CAP_ID_EXP) emulated by QEMU.  In our case we need the ATMU
window to extend beyond the end of ram, since the window size has
to be a power of 2.

Thanks,
Stuart

^ permalink raw reply	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2013-05-03  5:29 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2013-05-02 17:05 pci overmapping Yoder Stuart-B08248
2013-05-02 17:13 ` Scott Wood
2013-05-02 18:09   ` Sethi Varun-B16395
2013-05-02 18:19     ` Scott Wood
2013-05-03  5:29       ` Sethi Varun-B16395

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).