powerpc/powernv: Provide facilities for EOI, usable from real mode

This adds a new function pnv_opal_pci_msi_eoi() which does the part of
end-of-interrupt (EOI) handling of an MSI which involves doing an
OPAL call.  This function can be called in real mode.  This doesn't
just export pnv_ioda2_msi_eoi() because that does a call to
icp_native_eoi(), which does not work in real mode.

This also adds a function, is_pnv_opal_msi(), which KVM can call to
check whether an interrupt is one for which we should be calling
pnv_opal_pci_msi_eoi() when we need to do an EOI.

[paulus@ozlabs.org - split out the addition of pnv_opal_pci_msi_eoi()
 from Suresh's patch "KVM: PPC: Book3S HV: Handle passthrough
 interrupts in guest"; added is_pnv_opal_msi(); wrote description.]

Signed-off-by: Suresh Warrier <warrier@linux.vnet.ibm.com>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>

1 files changed, 3 insertions, 0 deletions

diff --git a/arch/powerpc/include/asm/pnv-pci.h b/arch/powerpc/include/asm/pnv-pci.h
index 0cbd8134ce81..1b46b52d3212 100644
--- a/arch/powerpc/include/asm/pnv-pci.h
+++ b/arch/powerpc/include/asm/pnv-pci.h
@@ -12,6 +12,7 @@
 
 #include <linux/pci.h>
 #include <linux/pci_hotplug.h>
+#include <linux/irq.h>
 #include <misc/cxl-base.h>
 #include <asm/opal-api.h>
 
@@ -33,6 +34,8 @@ int pnv_cxl_alloc_hwirqs(struct pci_dev *dev, int num);
 void pnv_cxl_release_hwirqs(struct pci_dev *dev, int hwirq, int num);
 int pnv_cxl_get_irq_count(struct pci_dev *dev);
 struct device_node *pnv_pci_get_phb_node(struct pci_dev *dev);
+int64_t pnv_opal_pci_msi_eoi(struct irq_chip *chip, unsigned int hw_irq);
+bool is_pnv_opal_msi(struct irq_chip *chip);
 
 #ifdef CONFIG_CXL_BASE
 int pnv_cxl_alloc_hwirq_ranges(struct cxl_irq_ranges *irqs,