powerpc/powernv: Patch MSI EOI handler on P8

The EOI handler of MSI/MSI-X interrupts for P8 (PHB3) need additional
steps to handle the P/Q bits in IVE before EOIing the corresponding
interrupt. The patch changes the EOI handler to cover that. we have
individual IRQ chip in each PHB instance. During the MSI IRQ setup
time, the IRQ chip is copied over from the original one for that IRQ,
and the EOI handler is patched with the one that will handle the P/Q
bits (As Ben suggested).

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

5 files changed, 46 insertions, 7 deletions

diff --git a/arch/powerpc/platforms/powernv/opal-wrappers.S b/arch/powerpc/platforms/powernv/opal-wrappers.S
index 3bb07e5e43cd..6fabe92eafb6 100644
--- a/arch/powerpc/platforms/powernv/opal-wrappers.S
+++ b/arch/powerpc/platforms/powernv/opal-wrappers.S
@@ -107,3 +107,4 @@ OPAL_CALL(opal_pci_mask_pe_error,		OPAL_PCI_MASK_PE_ERROR);
 OPAL_CALL(opal_set_slot_led_status,             OPAL_SET_SLOT_LED_STATUS);
 OPAL_CALL(opal_get_epow_status,                 OPAL_GET_EPOW_STATUS);
 OPAL_CALL(opal_set_system_attention_led,        OPAL_SET_SYSTEM_ATTENTION_LED);
+OPAL_CALL(opal_pci_msi_eoi,                     OPAL_PCI_MSI_EOI);
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 3d4e9588a695..3f88c51cb95b 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -31,6 +31,7 @@
 #include <asm/opal.h>
 #include <asm/iommu.h>
 #include <asm/tce.h>
+#include <asm/xics.h>
 
 #include "powernv.h"
 #include "pci.h"
@@ -589,11 +590,27 @@ static void pnv_ioda_setup_dma(struct pnv_phb *phb)
 }
 
 #ifdef CONFIG_PCI_MSI
+static void pnv_ioda2_msi_eoi(struct irq_data *d)
+{
+        unsigned int hw_irq = (unsigned int)irqd_to_hwirq(d);
+        struct irq_chip *chip = irq_data_get_irq_chip(d);
+        struct pnv_phb *phb = container_of(chip, struct pnv_phb,
+                                           ioda.irq_chip);
+        int64_t rc;
+
+        rc = opal_pci_msi_eoi(phb->opal_id, hw_irq);
+        WARN_ON_ONCE(rc);
+
+        icp_native_eoi(d);
+}
+
 static int pnv_pci_ioda_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
-                                  unsigned int hwirq, unsigned int is_64,
-                                  struct msi_msg *msg)
+                                  unsigned int hwirq, unsigned int virq,
+                                  unsigned int is_64, struct msi_msg *msg)
 {
         struct pnv_ioda_pe *pe = pnv_ioda_get_pe(dev);
+        struct irq_data *idata;
+        struct irq_chip *ichip;
         unsigned int xive_num = hwirq - phb->msi_base;
         uint64_t addr64;
         uint32_t addr32, data;
@@ -638,6 +655,23 @@ static int pnv_pci_ioda_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
         }
         msg->data = data;
 
+        /*
+         * Change the IRQ chip for the MSI interrupts on PHB3.
+         * The corresponding IRQ chip should be populated for
+         * the first time.
+         */
+        if (phb->type == PNV_PHB_IODA2) {
+                if (!phb->ioda.irq_chip_init) {
+                        idata = irq_get_irq_data(virq);
+                        ichip = irq_data_get_irq_chip(idata);
+                        phb->ioda.irq_chip_init = 1;
+                        phb->ioda.irq_chip = *ichip;
+                        phb->ioda.irq_chip.irq_eoi = pnv_ioda2_msi_eoi;
+                }
+
+                irq_set_chip(virq, &phb->ioda.irq_chip);
+        }
+
         pr_devel("%s: %s-bit MSI on hwirq %x (xive #%d),"
                  " address=%x_%08x data=%x PE# %d\n",
                  pci_name(dev), is_64 ? "64" : "32", hwirq, xive_num,
diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
index d5c066ea7d1f..92b37a0186c9 100644
--- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
+++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
@@ -42,8 +42,8 @@
 
 #ifdef CONFIG_PCI_MSI
 static int pnv_pci_p5ioc2_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
-                                    unsigned int hwirq, unsigned int is_64,
-                                    struct msi_msg *msg)
+                                    unsigned int hwirq, unsigned int virq,
+                                    unsigned int is_64, struct msi_msg *msg)
 {
         if (WARN_ON(!is_64))
                 return -ENXIO;
diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index a11b5a60c91e..861e185483fe 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -84,7 +84,7 @@ static int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
                         return -ENOMEM;
                 }
                 rc = phb->msi_setup(phb, pdev, phb->msi_base + hwirq,
-                                    entry->msi_attrib.is_64, &msg);
+                                    virq, entry->msi_attrib.is_64, &msg);
                 if (rc) {
                         pr_warn("%s: Failed to setup MSI\n", pci_name(pdev));
                         irq_dispose_mapping(virq);
diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
index f6314d65c4d9..3c552b3dd0c6 100644
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -79,8 +79,8 @@ struct pnv_phb {
         struct msi_bitmap       msi_bmp;
 #endif
         int (*msi_setup)(struct pnv_phb *phb, struct pci_dev *dev,
-                         unsigned int hwirq, unsigned int is_64,
-                         struct msi_msg *msg);
+                         unsigned int hwirq, unsigned int virq,
+                         unsigned int is_64, struct msi_msg *msg);
         void (*dma_dev_setup)(struct pnv_phb *phb, struct pci_dev *pdev);
         void (*fixup_phb)(struct pci_controller *hose);
         u32 (*bdfn_to_pe)(struct pnv_phb *phb, struct pci_bus *bus, u32 devfn);
@@ -108,6 +108,10 @@ struct pnv_phb {
                         unsigned int            *io_segmap;
                         struct pnv_ioda_pe      *pe_array;
 
+                        /* IRQ chip */
+                        int                     irq_chip_init;
+                        struct irq_chip         irq_chip;
+
                         /* Sorted list of used PE's based
                          * on the sequence of creation
                          */