[Qemu-devel] Re: [PATCH] pci: w1cmask[PCI_BRIDGE_CONTROL] initialized incorrectly

[Isaku Yamahata <yamahata@valinux.co.jp>]

The bit should be writable, not w1c.

3.2.5.18 bridge control register
bit 11 Discard Timer SERR# Enable

  When set to 1, this bit enables the bridge to assert SERR# on
  the primary interface when either the Primary Discard Timer or
  Secondary Discard Timer expires and a Delayed Transaction is
  discarded from a queue in the bridge. The default state of this
  bit must be 0 after reset.
  0 - do not assert SERR# on the primary interface as
  a result of the expiration of either the Primary
  Discard Timer or Secondary Discard Timer
  1 - assert SERR# on the primary interface if either
  the Primary Discard Timer or Secondary Discard
  Timer expires and a Delayed Transaction


On Wed, Jan 26, 2011 at 02:09:59PM +0200, Michael S. Tsirkin wrote:
> On Wed, Jan 26, 2011 at 06:45:27PM +0900, Isaku Yamahata wrote:
> > pci_init_wmask_bridge() incorrectly set w1cmask[PCI_BRIDGE_CONTROL].
> > This patch removes the line otherwise the assert(!(wmask & w1cmask)) in
> > pci_default_write_config() is hit.
> > 
> > Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
> 
> Maybe clear in wmask? This bit really should be w1c, should it not?
> 
> > ---
> >  hw/pci.c |    4 ----
> >  1 files changed, 0 insertions(+), 4 deletions(-)
> > 
> > diff --git a/hw/pci.c b/hw/pci.c
> > index b8f5385..79a46e7 100644
> > --- a/hw/pci.c
> > +++ b/hw/pci.c
> > @@ -643,10 +643,6 @@ static void pci_init_wmask_bridge(PCIDevice *d)
> >                   PCI_BRIDGE_CTL_SEC_DISCARD |
> >                   PCI_BRIDGE_CTL_DISCARD_STATUS |
> >                   PCI_BRIDGE_CTL_DISCARD_SERR);
> > -    /* Below does not do anything as we never set this bit, put here for
> > -     * completeness. */
> > -    pci_set_word(d->w1cmask + PCI_BRIDGE_CONTROL,
> > -                 PCI_BRIDGE_CTL_DISCARD_STATUS);
> >  }
> >  
> >  static int pci_init_multifunction(PCIBus *bus, PCIDevice *dev)
> > -- 
> > 1.7.1.1
> 

-- 
yamahata