Jean Guyader
2012-May-10 11:11 UTC
[PATCH] qemu-xen-traditional: Enable MSI after host sleep
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@gmail.com> _______________________________________________ Xen-devel mailing list Xen-devel@lists.xen.org http://lists.xen.org/xen-devel
Stefano Stabellini
2012-May-10 16:56 UTC
Re: [PATCH] qemu-xen-traditional: Enable MSI after host sleep
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@gmail.com> > > > diff --git a/hw/pass-through.c b/hw/pass-through.c > index f832c5a..5c32a2e 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, > @@ -3835,6 +3850,14 @@ static int pt_msgctrl_reg_write(struct pt_dev *ptdev, > ptdev->msi->flags &= ~MSI_FLAG_UNINIT; > ptdev->msi->flags |= PT_MSI_MAPPED; > } > + else > + { > + if (!msi_is_enable(ptdev)) > + { > + pt_msi_setup(ptdev); > + pt_msi_update(ptdev); > + } > + } > ptdev->msi->flags |= PCI_MSI_FLAGS_ENABLE; > } > elseWould it make sense to replace the condition above: if (ptdev->msi->flags & MSI_FLAG_UNINIT) with the new condition you wrote? if (!msi_is_enable(ptdev)) It seems more reliable to me.