Merge branch 'pci/iova-dma-ranges'

  - Add list of legal DMA address ranges to PCI host bridge (Srinath
    Mannam)

  - Reserve inaccessible DMA ranges so IOMMU doesn't allocate them (Srinath
    Mannam)

  - Parse iProc DT dma-ranges to learn what PCI devices can reach via DMA
    (Srinath Mannam)

* pci/iova-dma-ranges:
  PCI: iproc: Add sorted dma ranges resource entries to host bridge
  iommu/dma: Reserve IOVA for PCIe inaccessible DMA address
  PCI: Add dma_ranges window list

# Conflicts:
#	drivers/pci/probe.c

4 files changed, 78 insertions, 4 deletions

diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index 77aabe637a60..954ae11461a3 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -206,12 +206,13 @@ static int cookie_init_hw_msi_region(struct iommu_dma_cookie *cookie,
 	return 0;
 }
 
-static void iova_reserve_pci_windows(struct pci_dev *dev,
+static int iova_reserve_pci_windows(struct pci_dev *dev,
 		struct iova_domain *iovad)
 {
 	struct pci_host_bridge *bridge = pci_find_host_bridge(dev->bus);
 	struct resource_entry *window;
 	unsigned long lo, hi;
+	phys_addr_t start = 0, end;
 
 	resource_list_for_each_entry(window, &bridge->windows) {
 		if (resource_type(window->res) != IORESOURCE_MEM)
@@ -221,6 +222,31 @@ static void iova_reserve_pci_windows(struct pci_dev *dev,
 		hi = iova_pfn(iovad, window->res->end - window->offset);
 		reserve_iova(iovad, lo, hi);
 	}
+
+	/* Get reserved DMA windows from host bridge */
+	resource_list_for_each_entry(window, &bridge->dma_ranges) {
+		end = window->res->start - window->offset;
+resv_iova:
+		if (end > start) {
+			lo = iova_pfn(iovad, start);
+			hi = iova_pfn(iovad, end);
+			reserve_iova(iovad, lo, hi);
+		} else {
+			/* dma_ranges list should be sorted */
+			dev_err(&dev->dev, "Failed to reserve IOVA\n");
+			return -EINVAL;
+		}
+
+		start = window->res->end - window->offset + 1;
+		/* If window is last entry */
+		if (window->node.next == &bridge->dma_ranges &&
+		    end != ~(dma_addr_t)0) {
+			end = ~(dma_addr_t)0;
+			goto resv_iova;
+		}
+	}
+
+	return 0;
 }
 
 static int iova_reserve_iommu_regions(struct device *dev,
@@ -232,8 +258,11 @@ static int iova_reserve_iommu_regions(struct device *dev,
 	LIST_HEAD(resv_regions);
 	int ret = 0;
 
-	if (dev_is_pci(dev))
-		iova_reserve_pci_windows(to_pci_dev(dev), iovad);
+	if (dev_is_pci(dev)) {
+		ret = iova_reserve_pci_windows(to_pci_dev(dev), iovad);
+		if (ret)
+			return ret;
+	}
 
 	iommu_get_resv_regions(dev, &resv_regions);
 	list_for_each_entry(region, &resv_regions, list) {
diff --git a/drivers/pci/controller/pcie-iproc.c b/drivers/pci/controller/pcie-iproc.c
index aa4768a2c0ca..e3ca46497470 100644
--- a/drivers/pci/controller/pcie-iproc.c
+++ b/drivers/pci/controller/pcie-iproc.c
@@ -1182,11 +1182,43 @@ err_ib:
 	return ret;
 }
 
+static int iproc_pcie_add_dma_range(struct device *dev,
+				    struct list_head *resources,
+				    struct of_pci_range *range)
+{
+	struct resource *res;
+	struct resource_entry *entry, *tmp;
+	struct list_head *head = resources;
+
+	res = devm_kzalloc(dev, sizeof(struct resource), GFP_KERNEL);
+	if (!res)
+		return -ENOMEM;
+
+	resource_list_for_each_entry(tmp, resources) {
+		if (tmp->res->start < range->cpu_addr)
+			head = &tmp->node;
+	}
+
+	res->start = range->cpu_addr;
+	res->end = res->start + range->size - 1;
+
+	entry = resource_list_create_entry(res, 0);
+	if (!entry)
+		return -ENOMEM;
+
+	entry->offset = res->start - range->cpu_addr;
+	resource_list_add(entry, head);
+
+	return 0;
+}
+
 static int iproc_pcie_map_dma_ranges(struct iproc_pcie *pcie)
 {
+	struct pci_host_bridge *host = pci_host_bridge_from_priv(pcie);
 	struct of_pci_range range;
 	struct of_pci_range_parser parser;
 	int ret;
+	LIST_HEAD(resources);
 
 	/* Get the dma-ranges from DT */
 	ret = of_pci_dma_range_parser_init(&parser, pcie->dev->of_node);
@@ -1194,13 +1226,23 @@ static int iproc_pcie_map_dma_ranges(struct iproc_pcie *pcie)
 		return ret;
 
 	for_each_of_pci_range(&parser, &range) {
+		ret = iproc_pcie_add_dma_range(pcie->dev,
+					       &resources,
+					       &range);
+		if (ret)
+			goto out;
 		/* Each range entry corresponds to an inbound mapping region */
 		ret = iproc_pcie_setup_ib(pcie, &range, IPROC_PCIE_IB_MAP_MEM);
 		if (ret)
-			return ret;
+			goto out;
 	}
 
+	list_splice_init(&resources, &host->dma_ranges);
+
 	return 0;
+out:
+	pci_free_resource_list(&resources);
+	return ret;
 }
 
 static int iproce_pcie_get_msi(struct iproc_pcie *pcie,
diff --git a/drivers/pci/probe.c b/drivers/pci/probe.c
index 50cd9c17c08f..0dc42f0eb66d 100644
--- a/drivers/pci/probe.c
+++ b/drivers/pci/probe.c
@@ -589,6 +589,7 @@ static void pci_release_host_bridge_dev(struct device *dev)
 static void pci_init_host_bridge(struct pci_host_bridge *bridge)
 {
 	INIT_LIST_HEAD(&bridge->windows);
+	INIT_LIST_HEAD(&bridge->dma_ranges);
 
 	/*
 	 * We assume we can manage these PCIe features.  Some systems may
@@ -637,6 +638,7 @@ EXPORT_SYMBOL(devm_pci_alloc_host_bridge);
 void pci_free_host_bridge(struct pci_host_bridge *bridge)
 {
 	pci_free_resource_list(&bridge->windows);
+	pci_free_resource_list(&bridge->dma_ranges);
 
 	kfree(bridge);
 }
diff --git a/include/linux/pci.h b/include/linux/pci.h
index 6fc361a69e0c..87edbd23eddb 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -492,6 +492,7 @@ struct pci_host_bridge {
 	void		*sysdata;
 	int		busnr;
 	struct list_head windows;	/* resource_entry */
+	struct list_head dma_ranges;	/* dma ranges resource list */
 	u8 (*swizzle_irq)(struct pci_dev *, u8 *); /* Platform IRQ swizzler */
 	int (*map_irq)(const struct pci_dev *, u8, u8);
 	void (*release_fn)(struct pci_host_bridge *);