--- drivers/pci/msi.c

+++ drivers/pci/msi.c

@@ -195,6 +195,9 @@ void unmask_msi_irq(unsigned int irq)

void read_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg)

{

struct msi_desc *entry = get_irq_desc_msi(desc);

+

+ BUG_ON(entry->dev->current_state != PCI_D0);

+

if (entry->msi_attrib.is_msix) {

void __iomem *base = entry->mask_base +

entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;

@@ -228,10 +231,32 @@ void read_msi_msg(unsigned int irq, stru

read_msi_msg_desc(desc, msg);

}

+void get_cached_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg)

+{

+ struct msi_desc *entry = get_irq_desc_msi(desc);

+

+ /* Assert that the cache is valid, assuming that

+ * valid messages are not all-zeroes. */

+ BUG_ON(!(entry->msg.address_hi | entry->msg.address_lo |

+ entry->msg.data));

+

+ *msg = entry->msg;

+}

+

+void get_cached_msi_msg(unsigned int irq, struct msi_msg *msg)

+{

+ struct irq_desc *desc = irq_to_desc(irq);

+

+ get_cached_msi_msg_desc(desc, msg);

+}

+

void write_msi_msg_desc(struct irq_desc *desc, struct msi_msg *msg)

{

struct msi_desc *entry = get_irq_desc_msi(desc);

- if (entry->msi_attrib.is_msix) {

+

+ if (entry->dev->current_state != PCI_D0) {

+ /* Don't touch the hardware now */

+ } else if (entry->msi_attrib.is_msix) {

void __iomem *base;

base = entry->mask_base +

entry->msi_attrib.entry_nr * PCI_MSIX_ENTRY_SIZE;