| Message ID | 1407966975-3723-3-git-send-email-jsnow@redhat.com |
|---|---|
| State | New |
| Headers | show |
On Wed, Aug 13, 2014 at 05:56:09PM -0400, John Snow wrote: > In the Intel ICH9 data sheet, the MSI capability offset > in the PCI configuration space for ICH9 AHCI devices is > specified to be 0x80. > > Further, the PCI capability pointer should always point > to 0x80 in ICH9 devices, despite the fact that AHCI 1.3 > specifies that it should be pointing to PMCAP (Which in > this instance would be 0x70) to maintain adherence to > the Intel data sheet specifications and real observed behavior. > > Signed-off-by: John Snow <jsnow@redhat.com> > --- > hw/ide/ich.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/hw/ide/ich.c b/hw/ide/ich.c > index a2f1639..d2a3ac2 100644 > --- a/hw/ide/ich.c > +++ b/hw/ide/ich.c > @@ -71,6 +71,7 @@ > #include <hw/ide/pci.h> > #include <hw/ide/ahci.h> > > +#define ICH9_MSI_CAP_OFFSET 0x80 > #define ICH9_SATA_CAP_OFFSET 0xA8 > > #define ICH9_IDP_BAR 4 > @@ -115,7 +116,6 @@ static int pci_ich9_ahci_init(PCIDevice *dev) > /* XXX Software should program this register */ > dev->config[0x90] = 1 << 6; /* Address Map Register - AHCI mode */ > > - msi_init(dev, 0x50, 1, true, false); > d->ahci.irq = pci_allocate_irq(dev); > > pci_register_bar(dev, ICH9_IDP_BAR, PCI_BASE_ADDRESS_SPACE_IO, > @@ -135,6 +135,9 @@ static int pci_ich9_ahci_init(PCIDevice *dev) > (ICH9_IDP_BAR + 0x4) | (ICH9_IDP_INDEX_LOG2 << 4)); > d->ahci.idp_offset = ICH9_IDP_INDEX; > > + /* MSI cap should be added last to be first. */ I would put the explanation from the commit log somewhere around this comment otherwise we risk someone noting ahci spec says otherwise and sending a patch "fixing" it. > + msi_init(dev, ICH9_MSI_CAP_OFFSET, 1, true, false); > + > return 0; > } > > -- > 1.9.3
On Wed, Aug 13, 2014 at 05:56:09PM -0400, John Snow wrote: > In the Intel ICH9 data sheet, the MSI capability offset > in the PCI configuration space for ICH9 AHCI devices is > specified to be 0x80. > > Further, the PCI capability pointer should always point > to 0x80 in ICH9 devices, despite the fact that AHCI 1.3 > specifies that it should be pointing to PMCAP (Which in > this instance would be 0x70) to maintain adherence to > the Intel data sheet specifications and real observed behavior. > > Signed-off-by: John Snow <jsnow@redhat.com> Besides the comment I sent previously: Reviewed-by: Michael S. Tsirkin <mst@redhat.com> > --- > hw/ide/ich.c | 5 ++++- > 1 file changed, 4 insertions(+), 1 deletion(-) > > diff --git a/hw/ide/ich.c b/hw/ide/ich.c > index a2f1639..d2a3ac2 100644 > --- a/hw/ide/ich.c > +++ b/hw/ide/ich.c > @@ -71,6 +71,7 @@ > #include <hw/ide/pci.h> > #include <hw/ide/ahci.h> > > +#define ICH9_MSI_CAP_OFFSET 0x80 > #define ICH9_SATA_CAP_OFFSET 0xA8 > > #define ICH9_IDP_BAR 4 > @@ -115,7 +116,6 @@ static int pci_ich9_ahci_init(PCIDevice *dev) > /* XXX Software should program this register */ > dev->config[0x90] = 1 << 6; /* Address Map Register - AHCI mode */ > > - msi_init(dev, 0x50, 1, true, false); > d->ahci.irq = pci_allocate_irq(dev); > > pci_register_bar(dev, ICH9_IDP_BAR, PCI_BASE_ADDRESS_SPACE_IO, > @@ -135,6 +135,9 @@ static int pci_ich9_ahci_init(PCIDevice *dev) > (ICH9_IDP_BAR + 0x4) | (ICH9_IDP_INDEX_LOG2 << 4)); > d->ahci.idp_offset = ICH9_IDP_INDEX; > > + /* MSI cap should be added last to be first. */ > + msi_init(dev, ICH9_MSI_CAP_OFFSET, 1, true, false); > + > return 0; > } > > -- > 1.9.3
diff --git a/hw/ide/ich.c b/hw/ide/ich.c index a2f1639..d2a3ac2 100644 --- a/hw/ide/ich.c +++ b/hw/ide/ich.c @@ -71,6 +71,7 @@ #include <hw/ide/pci.h> #include <hw/ide/ahci.h> +#define ICH9_MSI_CAP_OFFSET 0x80 #define ICH9_SATA_CAP_OFFSET 0xA8 #define ICH9_IDP_BAR 4 @@ -115,7 +116,6 @@ static int pci_ich9_ahci_init(PCIDevice *dev) /* XXX Software should program this register */ dev->config[0x90] = 1 << 6; /* Address Map Register - AHCI mode */ - msi_init(dev, 0x50, 1, true, false); d->ahci.irq = pci_allocate_irq(dev); pci_register_bar(dev, ICH9_IDP_BAR, PCI_BASE_ADDRESS_SPACE_IO, @@ -135,6 +135,9 @@ static int pci_ich9_ahci_init(PCIDevice *dev) (ICH9_IDP_BAR + 0x4) | (ICH9_IDP_INDEX_LOG2 << 4)); d->ahci.idp_offset = ICH9_IDP_INDEX; + /* MSI cap should be added last to be first. */ + msi_init(dev, ICH9_MSI_CAP_OFFSET, 1, true, false); + return 0; }
In the Intel ICH9 data sheet, the MSI capability offset in the PCI configuration space for ICH9 AHCI devices is specified to be 0x80. Further, the PCI capability pointer should always point to 0x80 in ICH9 devices, despite the fact that AHCI 1.3 specifies that it should be pointing to PMCAP (Which in this instance would be 0x70) to maintain adherence to the Intel data sheet specifications and real observed behavior. Signed-off-by: John Snow <jsnow@redhat.com> --- hw/ide/ich.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)