PPC: POWERNV: move iommu_add_device earlier

The current implementation of IOMMU on sPAPR does not use iommu_ops
and therefore does not call IOMMU API's bus_set_iommu() which
1) sets iommu_ops for a bus
2) registers a bus notifier
Instead, PCI devices are added to IOMMU groups from
subsys_initcall_sync(tce_iommu_init) which does basically the same
thing without using iommu_ops callbacks.

However Freescale PAMU driver (https://lkml.org/lkml/2013/7/1/158)
implements iommu_ops and when tce_iommu_init is called, every PCI device
is already added to some group so there is a conflict.

This patch does 2 things:
1. removes the loop in which PCI devices were added to groups and
adds explicit iommu_add_device() calls to add devices as soon as they get
the iommu_table pointer assigned to them.
2. moves a bus notifier to powernv code in order to avoid conflict with
the notifier from Freescale driver.

iommu_add_device() and iommu_del_device() are public now.

Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>

6 files changed, 72 insertions, 53 deletions

diff --git a/arch/powerpc/include/asm/iommu.h b/arch/powerpc/include/asm/iommu.h
index c34656a8925e..774fa2776907 100644
--- a/arch/powerpc/include/asm/iommu.h
+++ b/arch/powerpc/include/asm/iommu.h
@@ -101,8 +101,34 @@ extern void iommu_free_table(struct iommu_table *tbl, const char *node_name);
  */
 extern struct iommu_table *iommu_init_table(struct iommu_table * tbl,
                                             int nid);
+#ifdef CONFIG_IOMMU_API
 extern void iommu_register_group(struct iommu_table *tbl,
                                  int pci_domain_number, unsigned long pe_num);
+extern int iommu_add_device(struct device *dev);
+extern void iommu_del_device(struct device *dev);
+#else
+static inline void iommu_register_group(struct iommu_table *tbl,
+                                        int pci_domain_number,
+                                        unsigned long pe_num)
+{
+}
+
+static inline int iommu_add_device(struct device *dev)
+{
+        return 0;
+}
+
+static inline void iommu_del_device(struct device *dev)
+{
+}
+#endif /* !CONFIG_IOMMU_API */
+
+static inline void set_iommu_table_base_and_group(struct device *dev,
+                                                  void *base)
+{
+        set_iommu_table_base(dev, base);
+        iommu_add_device(dev);
+}
 
 extern int iommu_map_sg(struct device *dev, struct iommu_table *tbl,
                         struct scatterlist *sglist, int nelems,
diff --git a/arch/powerpc/kernel/iommu.c b/arch/powerpc/kernel/iommu.c
index 572bb5b95f35..d22abe0b08e3 100644
--- a/arch/powerpc/kernel/iommu.c
+++ b/arch/powerpc/kernel/iommu.c
@@ -1105,7 +1105,7 @@ void iommu_release_ownership(struct iommu_table *tbl)
 }
 EXPORT_SYMBOL_GPL(iommu_release_ownership);
 
-static int iommu_add_device(struct device *dev)
+int iommu_add_device(struct device *dev)
 {
         struct iommu_table *tbl;
         int ret = 0;
@@ -1134,52 +1134,12 @@ static int iommu_add_device(struct device *dev)
 
         return ret;
 }
+EXPORT_SYMBOL_GPL(iommu_add_device);
 
-static void iommu_del_device(struct device *dev)
+void iommu_del_device(struct device *dev)
 {
         iommu_group_remove_device(dev);
 }
-
-static int iommu_bus_notifier(struct notifier_block *nb,
-                              unsigned long action, void *data)
-{
-        struct device *dev = data;
-
-        switch (action) {
-        case BUS_NOTIFY_ADD_DEVICE:
-                return iommu_add_device(dev);
-        case BUS_NOTIFY_DEL_DEVICE:
-                iommu_del_device(dev);
-                return 0;
-        default:
-                return 0;
-        }
-}
-
-static struct notifier_block tce_iommu_bus_nb = {
-        .notifier_call = iommu_bus_notifier,
-};
-
-static int __init tce_iommu_init(void)
-{
-        struct pci_dev *pdev = NULL;
-
-        BUILD_BUG_ON(PAGE_SIZE < IOMMU_PAGE_SIZE);
-
-        for_each_pci_dev(pdev)
-                iommu_add_device(&pdev->dev);
-
-        bus_register_notifier(&pci_bus_type, &tce_iommu_bus_nb);
-        return 0;
-}
-
-subsys_initcall_sync(tce_iommu_init);
-
-#else
-
-void iommu_register_group(struct iommu_table *tbl,
-                int pci_domain_number, unsigned long pe_num)
-{
-}
+EXPORT_SYMBOL_GPL(iommu_del_device);
 
 #endif /* CONFIG_IOMMU_API */
diff --git a/arch/powerpc/platforms/powernv/pci-ioda.c b/arch/powerpc/platforms/powernv/pci-ioda.c
index 084cdfa40682..614356cac466 100644
--- a/arch/powerpc/platforms/powernv/pci-ioda.c
+++ b/arch/powerpc/platforms/powernv/pci-ioda.c
@@ -460,7 +460,7 @@ static void pnv_pci_ioda_dma_dev_setup(struct pnv_phb *phb, struct pci_dev *pdev
                 return;
 
         pe = &phb->ioda.pe_array[pdn->pe_number];
-        set_iommu_table_base(&pdev->dev, &pe->tce32_table);
+        set_iommu_table_base_and_group(&pdev->dev, &pe->tce32_table);
 }
 
 static void pnv_ioda_setup_bus_dma(struct pnv_ioda_pe *pe, struct pci_bus *bus)
@@ -468,7 +468,7 @@ static void pnv_ioda_setup_bus_dma(struct pnv_ioda_pe *pe, struct pci_bus *bus)
         struct pci_dev *dev;
 
         list_for_each_entry(dev, &bus->devices, bus_list) {
-                set_iommu_table_base(&dev->dev, &pe->tce32_table);
+                set_iommu_table_base_and_group(&dev->dev, &pe->tce32_table);
                 if (dev->subordinate)
                         pnv_ioda_setup_bus_dma(pe, dev->subordinate);
         }
@@ -644,7 +644,7 @@ static void pnv_pci_ioda_setup_dma_pe(struct pnv_phb *phb,
         iommu_register_group(tbl, pci_domain_nr(pe->pbus), pe->pe_number);
 
         if (pe->pdev)
-                set_iommu_table_base(&pe->pdev->dev, tbl);
+                set_iommu_table_base_and_group(&pe->pdev->dev, tbl);
         else
                 pnv_ioda_setup_bus_dma(pe, pe->pbus);
 
@@ -722,7 +722,7 @@ static void pnv_pci_ioda2_setup_dma_pe(struct pnv_phb *phb,
         iommu_init_table(tbl, phb->hose->node);
 
         if (pe->pdev)
-                set_iommu_table_base(&pe->pdev->dev, tbl);
+                set_iommu_table_base_and_group(&pe->pdev->dev, tbl);
         else
                 pnv_ioda_setup_bus_dma(pe, pe->pbus);
 
diff --git a/arch/powerpc/platforms/powernv/pci-p5ioc2.c b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
index f8b4bd8afb2e..e3807d69393e 100644
--- a/arch/powerpc/platforms/powernv/pci-p5ioc2.c
+++ b/arch/powerpc/platforms/powernv/pci-p5ioc2.c
@@ -92,7 +92,7 @@ static void pnv_pci_p5ioc2_dma_dev_setup(struct pnv_phb *phb,
                                 pci_domain_nr(phb->hose->bus), phb->opal_id);
         }
 
-        set_iommu_table_base(&pdev->dev, &phb->p5ioc2.iommu_table);
+        set_iommu_table_base_and_group(&pdev->dev, &phb->p5ioc2.iommu_table);
 }
 
 static void __init pnv_pci_init_p5ioc2_phb(struct device_node *np, u64 hub_id,
diff --git a/arch/powerpc/platforms/powernv/pci.c b/arch/powerpc/platforms/powernv/pci.c
index 4eb33a9ed532..6f3d49c18d64 100644
--- a/arch/powerpc/platforms/powernv/pci.c
+++ b/arch/powerpc/platforms/powernv/pci.c
@@ -536,7 +536,7 @@ static void pnv_pci_dma_fallback_setup(struct pci_controller *hose,
                 pdn->iommu_table = pnv_pci_setup_bml_iommu(hose);
         if (!pdn->iommu_table)
                 return;
-        set_iommu_table_base(&pdev->dev, pdn->iommu_table);
+        set_iommu_table_base_and_group(&pdev->dev, pdn->iommu_table);
 }
 
 static void pnv_pci_dma_dev_setup(struct pci_dev *pdev)
@@ -657,3 +657,34 @@ void __init pnv_pci_init(void)
         ppc_md.teardown_msi_irqs = pnv_teardown_msi_irqs;
 #endif
 }
+
+static int tce_iommu_bus_notifier(struct notifier_block *nb,
+                unsigned long action, void *data)
+{
+        struct device *dev = data;
+
+        switch (action) {
+        case BUS_NOTIFY_ADD_DEVICE:
+                return iommu_add_device(dev);
+        case BUS_NOTIFY_DEL_DEVICE:
+                if (dev->iommu_group)
+                        iommu_del_device(dev);
+                return 0;
+        default:
+                return 0;
+        }
+}
+
+static struct notifier_block tce_iommu_bus_nb = {
+        .notifier_call = tce_iommu_bus_notifier,
+};
+
+static int __init tce_iommu_bus_notifier_init(void)
+{
+        BUILD_BUG_ON(PAGE_SIZE < IOMMU_PAGE_SIZE);
+
+        bus_register_notifier(&pci_bus_type, &tce_iommu_bus_nb);
+        return 0;
+}
+
+subsys_initcall_sync(tce_iommu_bus_notifier_init);
diff --git a/arch/powerpc/platforms/pseries/iommu.c b/arch/powerpc/platforms/pseries/iommu.c
index f253361552ae..a80af6c20cba 100644
--- a/arch/powerpc/platforms/pseries/iommu.c
+++ b/arch/powerpc/platforms/pseries/iommu.c
@@ -687,7 +687,8 @@ static void pci_dma_dev_setup_pSeries(struct pci_dev *dev)
                 iommu_table_setparms(phb, dn, tbl);
                 PCI_DN(dn)->iommu_table = iommu_init_table(tbl, phb->node);
                 iommu_register_group(tbl, pci_domain_nr(phb->bus), 0);
-                set_iommu_table_base(&dev->dev, PCI_DN(dn)->iommu_table);
+                set_iommu_table_base_and_group(&dev->dev,
+                                               PCI_DN(dn)->iommu_table);
                 return;
         }
 
@@ -699,7 +700,8 @@ static void pci_dma_dev_setup_pSeries(struct pci_dev *dev)
                 dn = dn->parent;
 
         if (dn && PCI_DN(dn))
-                set_iommu_table_base(&dev->dev, PCI_DN(dn)->iommu_table);
+                set_iommu_table_base_and_group(&dev->dev,
+                                               PCI_DN(dn)->iommu_table);
         else
                 printk(KERN_WARNING "iommu: Device %s has no iommu table\n",
                        pci_name(dev));
@@ -1193,7 +1195,7 @@ static void pci_dma_dev_setup_pSeriesLP(struct pci_dev *dev)
                 pr_debug("  found DMA window, table: %p\n", pci->iommu_table);
         }
 
-        set_iommu_table_base(&dev->dev, pci->iommu_table);
+        set_iommu_table_base_and_group(&dev->dev, pci->iommu_table);
 }
 
 static int dma_set_mask_pSeriesLP(struct device *dev, u64 dma_mask)