powerpc/powernv: Use MSI bitmap to manage IRQs

As Michael Ellerman mentioned, arch/powerpc/sysdev/msi_bitmap.c
already implemented bitmap to manage (alloc/free) MSI interrupts.
The patch intends to use that mechanism to manage MSI interrupts
for PowerNV platform.

Signed-off-by: Gavin Shan <shangw@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>

diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 8e90e89..a5c5f15 100644 (file)
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -26,6 +26,7 @@
 #include <asm/prom.h>
 #include <asm/pci-bridge.h>
 #include <asm/machdep.h>
+#include <asm/msi_bitmap.h>
 #include <asm/ppc-pci.h>
 #include <asm/opal.h>
 #include <asm/iommu.h>
@@ -647,7 +648,7 @@ static int pnv_pci_ioda_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
 
 static void pnv_pci_init_ioda_msis(struct pnv_phb *phb)
 {
-       unsigned int bmap_size;
+       unsigned int count;
        const __be32 *prop = of_get_property(phb->hose->dn,
                                             "ibm,opal-msi-ranges", NULL);
        if (!prop) {
@@ -658,18 +659,17 @@ static void pnv_pci_init_ioda_msis(struct pnv_phb *phb)
                return;
 
        phb->msi_base = be32_to_cpup(prop);
-       phb->msi_count = be32_to_cpup(prop + 1);
-       bmap_size = BITS_TO_LONGS(phb->msi_count) * sizeof(unsigned long);
-       phb->msi_map = zalloc_maybe_bootmem(bmap_size, GFP_KERNEL);
-       if (!phb->msi_map) {
+       count = be32_to_cpup(prop + 1);
+       if (msi_bitmap_alloc(&phb->msi_bmp, count, phb->hose->dn)) {
                pr_err("PCI %d: Failed to allocate MSI bitmap !\n",
                       phb->hose->global_number);
                return;
        }
+
        phb->msi_setup = pnv_pci_ioda_msi_setup;
        phb->msi32_support = 1;
        pr_info("  Allocated bitmap for %d MSIs (base IRQ 0x%x)\n",
-               phb->msi_count, phb->msi_base);
+               count, phb->msi_base);
 }
 #else
 static void pnv_pci_init_ioda_msis(struct pnv_phb *phb) { }

diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
index 7db8771..d5c066e 100644 (file)
--- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
+++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
@@ -26,6 +26,7 @@
 #include <asm/prom.h>
 #include <asm/pci-bridge.h>
 #include <asm/machdep.h>
+#include <asm/msi_bitmap.h>
 #include <asm/ppc-pci.h>
 #include <asm/opal.h>
 #include <asm/iommu.h>
@@ -55,7 +56,7 @@ static int pnv_pci_p5ioc2_msi_setup(struct pnv_phb *phb, struct pci_dev *dev,
 
 static void pnv_pci_init_p5ioc2_msis(struct pnv_phb *phb)
 {
-       unsigned int bmap_size;
+       unsigned int count;
        const __be32 *prop = of_get_property(phb->hose->dn,
                                             "ibm,opal-msi-ranges", NULL);
        if (!prop)
@@ -67,10 +68,8 @@ static void pnv_pci_init_p5ioc2_msis(struct pnv_phb *phb)
        if (of_device_is_compatible(phb->hose->dn, "ibm,p5ioc2-pcix"))
                return;
        phb->msi_base = be32_to_cpup(prop);
-       phb->msi_count = be32_to_cpup(prop + 1);
-       bmap_size = BITS_TO_LONGS(phb->msi_count) * sizeof(unsigned long);
-       phb->msi_map = zalloc_maybe_bootmem(bmap_size, GFP_KERNEL);
-       if (!phb->msi_map) {
+       count = be32_to_cpup(prop + 1);
+       if (msi_bitmap_alloc(&phb->msi_bmp, count, phb->hose->dn)) {
                pr_err("PCI %d: Failed to allocate MSI bitmap !\n",
                       phb->hose->global_number);
                return;
@@ -78,7 +77,7 @@ static void pnv_pci_init_p5ioc2_msis(struct pnv_phb *phb)
        phb->msi_setup = pnv_pci_p5ioc2_msi_setup;
        phb->msi32_support = 0;
        pr_info(" Allocated bitmap for %d MSIs (base IRQ 0x%x)\n",
-               phb->msi_count, phb->msi_base);
+               count, phb->msi_base);
 }
 #else
 static void pnv_pci_init_p5ioc2_msis(struct pnv_phb *phb) { }

diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index b8b8e0b..42eee93 100644 (file)
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -26,6 +26,7 @@
 #include <asm/prom.h>
 #include <asm/pci-bridge.h>
 #include <asm/machdep.h>
+#include <asm/msi_bitmap.h>
 #include <asm/ppc-pci.h>
 #include <asm/opal.h>
 #include <asm/iommu.h>
@@ -47,43 +48,7 @@ static int pnv_msi_check_device(struct pci_dev* pdev, int nvec, int type)
        struct pci_controller *hose = pci_bus_to_host(pdev->bus);
        struct pnv_phb *phb = hose->private_data;
 
-       return (phb && phb->msi_map) ? 0 : -ENODEV;
-}
-
-static unsigned int pnv_get_one_msi(struct pnv_phb *phb)
-{
-       unsigned long flags;
-       unsigned int id, rc;
-
-       spin_lock_irqsave(&phb->lock, flags);
-
-       id = find_next_zero_bit(phb->msi_map, phb->msi_count, phb->msi_next);
-       if (id >= phb->msi_count && phb->msi_next)
-               id = find_next_zero_bit(phb->msi_map, phb->msi_count, 0);
-       if (id >= phb->msi_count) {
-               rc = 0;
-               goto out;
-       }
-       __set_bit(id, phb->msi_map);
-       rc = id + phb->msi_base;
-out:
-       spin_unlock_irqrestore(&phb->lock, flags);
-       return rc;
-}
-
-static void pnv_put_msi(struct pnv_phb *phb, unsigned int hwirq)
-{
-       unsigned long flags;
-       unsigned int id;
-
-       if (WARN_ON(hwirq < phb->msi_base ||
-                   hwirq >= (phb->msi_base + phb->msi_count)))
-               return;
-       id = hwirq - phb->msi_base;
-
-       spin_lock_irqsave(&phb->lock, flags);
-       __clear_bit(id, phb->msi_map);
-       spin_unlock_irqrestore(&phb->lock, flags);
+       return (phb && phb->msi_bmp.bitmap) ? 0 : -ENODEV;
 }
 
 static int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
@@ -92,7 +57,8 @@ static int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
        struct pnv_phb *phb = hose->private_data;
        struct msi_desc *entry;
        struct msi_msg msg;
-       unsigned int hwirq, virq;
+       int hwirq;
+       unsigned int virq;
        int rc;
 
        if (WARN_ON(!phb))
@@ -104,25 +70,25 @@ static int pnv_setup_msi_irqs(struct pci_dev *pdev, int nvec, int type)
                                pci_name(pdev));
                        return -ENXIO;
                }
-               hwirq = pnv_get_one_msi(phb);
-               if (!hwirq) {
+               hwirq = msi_bitmap_alloc_hwirqs(&phb->msi_bmp, 1);
+               if (hwirq < 0) {
                        pr_warn("%s: Failed to find a free MSI\n",
                                pci_name(pdev));
                        return -ENOSPC;
                }
-               virq = irq_create_mapping(NULL, hwirq);
+               virq = irq_create_mapping(NULL, phb->msi_base + hwirq);
                if (virq == NO_IRQ) {
                        pr_warn("%s: Failed to map MSI to linux irq\n",
                                pci_name(pdev));
-                       pnv_put_msi(phb, hwirq);
+                       msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, 1);
                        return -ENOMEM;
                }
-               rc = phb->msi_setup(phb, pdev, hwirq, entry->msi_attrib.is_64,
-                                   &msg);
+               rc = phb->msi_setup(phb, pdev, phb->msi_base + hwirq,
+                                   entry->msi_attrib.is_64, &msg);
                if (rc) {
                        pr_warn("%s: Failed to setup MSI\n", pci_name(pdev));
                        irq_dispose_mapping(virq);
-                       pnv_put_msi(phb, hwirq);
+                       msi_bitmap_free_hwirqs(&phb->msi_bmp, hwirq, 1);
                        return rc;
                }
                irq_set_msi_desc(virq, entry);
@@ -144,7 +110,8 @@ static void pnv_teardown_msi_irqs(struct pci_dev *pdev)
                if (entry->irq == NO_IRQ)
                        continue;
                irq_set_msi_desc(entry->irq, NULL);
-               pnv_put_msi(phb, virq_to_hw(entry->irq));
+               msi_bitmap_free_hwirqs(&phb->msi_bmp,
+                       virq_to_hw(entry->irq) - phb->msi_base, 1);
                irq_dispose_mapping(entry->irq);
        }
 }

diff --git a/arch/powerpc/platforms/powernv/pci.h b/arch/powerpc/platforms/powernv/pci.h
index 7cfb7c8..42ddfba 100644 (file)
--- a/arch/powerpc/platforms/powernv/pci.h
+++ b/arch/powerpc/platforms/powernv/pci.h
@@ -73,11 +73,9 @@ struct pnv_phb {
        spinlock_t              lock;
 
 #ifdef CONFIG_PCI_MSI
-       unsigned long           *msi_map;
        unsigned int            msi_base;
-       unsigned int            msi_count;
-       unsigned int            msi_next;
        unsigned int            msi32_support;
+       struct msi_bitmap       msi_bmp;
 #endif
        int (*msi_setup)(struct pnv_phb *phb, struct pci_dev *dev,
                         unsigned int hwirq, unsigned int is_64,