jean.guyader at gmail
May 24, 2012, 2:44 AM
Post #3 of 3
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Re: [PATCH] qemu-xen-traditional: Enable MSI after host sleep (v2)
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On 11 May 2012 17:06, Stefano Stabellini
<stefano.stabellini [at] eu>wrote:
> On Thu, 10 May 2012, Jean Guyader wrote:
> > After a host sleep MSI will be off on the host but qemu still thinks
> > it's on because of some state that have been set previously.
> >
> > If qemu thinks that the device has been configure already
> > and the host MSI are disabled tell Xen to reconfigure the MSI.
> >
> > Signed-off-by: Jean Guyader <jean.guyader [at] gmail>
> >
> > diff --git a/hw/pass-through.c b/hw/pass-through.c
> > index f832c5a..a6a9b7a 100644
> > --- a/hw/pass-through.c
> > +++ b/hw/pass-through.c
> > @@ -3772,6 +3772,21 @@ static int pt_pmcsr_reg_write(struct pt_dev
> *ptdev,
> > return 0;
> > }
> >
> > +static int msi_is_enable(struct pt_dev *dev)
> > +{
> > + uint16_t val = 0;
> > + uint32_t address = 0;
> > + if (!dev->msi)
> > + return 0;
> > +
> > + address = dev->msi->ctrl_offset;
> > + if (!address)
> > + return 0;
> > +
> > + val = pci_read_word(dev->pci_dev, address);
> > + return val & PCI_MSI_FLAGS_ENABLE;
> > +}
> > +
> > /* write Message Control register */
> > static int pt_msgctrl_reg_write(struct pt_dev *ptdev,
> > struct pt_reg_tbl *cfg_entry,
> > @@ -3803,8 +3818,7 @@ static int pt_msgctrl_reg_write(struct pt_dev
> *ptdev,
> > /* update MSI */
> > if (val & PCI_MSI_FLAGS_ENABLE)
> > {
> > - /* setup MSI pirq for the first time */
> > - if (ptdev->msi->flags & MSI_FLAG_UNINIT)
> > + if (!msi_is_enable(ptdev))
> > {
> > if (ptdev->msi_trans_en) {
> > PT_LOG("guest enabling MSI, disable MSI-INTx
> translation\n");
> > diff --git a/hw/pt-msi.c b/hw/pt-msi.c
> > index 70c4023..99f9afd 100644
> > --- a/hw/pt-msi.c
> > +++ b/hw/pt-msi.c
> > @@ -67,12 +67,6 @@ int pt_msi_setup(struct pt_dev *dev)
> > int pirq = -1;
> > uint8_t gvec = 0;
> >
> > - if ( !(dev->msi->flags & MSI_FLAG_UNINIT) )
> > - {
> > - PT_LOG("Error: setup physical after initialized?? \n");
> > - return -1;
> > - }
> > -
> > gvec = dev->msi->data & 0xFF;
> > if (!gvec) {
> > /* if gvec is 0, the guest is asking for a particular pirq that
>
> The patch makes sense.
> Only one last comment, sorry for not having noticed this before, but
> there might be another (flags & MSI_FLAG_UNINIT) check that should
> probably be changed into msi_is_enable in pt_msi_disable.
>
Also I think that we should always call pt_msi_setup (the first time) even
if the MSI are set in the config space.
It should maybe look like my first patch.
Jean
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msi-after-sleep.patch
