[PATCH 09/11] pci: Add function to validate PCI address range

[Andrew Scull <ascull@google.com>]

Add a function to convert a PCI address range to a physical address
range. The address range is validated to ensure it is contained within
one of the PCI address regions and that the whole range can be indexed
from the resulting physical address.

Signed-off-by: Andrew Scull <ascull@google.com>
---
 drivers/pci/pci-uclass.c | 30 ++++++++++++++++++++++++++++++
 include/pci.h            | 16 ++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/drivers/pci/pci-uclass.c b/drivers/pci/pci-uclass.c
index 54a05d7567..efab8916e2 100644
--- a/drivers/pci/pci-uclass.c
+++ b/drivers/pci/pci-uclass.c
@@ -1452,6 +1452,36 @@ phys_addr_t dm_pci_bus_to_phys(struct udevice *dev, pci_addr_t bus_addr,
 	return phys_addr;
 }
 
+phys_addr_t dm_pci_bus_range_to_phys(struct udevice *dev, pci_addr_t bus_addr,
+				     size_t size, unsigned long mask,
+				     unsigned long flags)
+{
+	struct udevice *ctlr = pci_get_controller(dev);
+	struct pci_controller *hose = dev_get_uclass_priv(ctlr);
+	struct pci_region *res;
+	size_t offset;
+	int i;
+
+	for (i = 0; i < hose->region_count; i++) {
+		res = &hose->regions[i];
+
+		if ((res->flags & mask) != flags)
+			continue;
+
+		if (bus_addr < res->bus_start)
+			continue;
+
+		offset = bus_addr - res->bus_start;
+		if (offset >= res->size || size > res->size - offset)
+			continue;
+
+		return res->phys_start + offset;
+	}
+
+	puts("pci_bus_range_to_phys: invalid address range\n");
+	return 0;
+}
+
 static int _dm_pci_phys_to_bus(struct udevice *dev, phys_addr_t phys_addr,
 			       unsigned long flags, unsigned long skip_mask,
 			       pci_addr_t *ba)
diff --git a/include/pci.h b/include/pci.h
index 673c95c6bb..15b3031c1f 100644
--- a/include/pci.h
+++ b/include/pci.h
@@ -1446,6 +1446,22 @@ u32 dm_pci_read_bar32(const struct udevice *dev, int barnum);
 phys_addr_t dm_pci_bus_to_phys(struct udevice *dev, pci_addr_t addr,
 			       unsigned long flags);
 
+/**
+ * dm_pci_bus_range_to_phys() - convert a PCI bus address range to a physical
+ *				address.
+ *
+ * @dev:	Device containing the PCI address
+ * @addr:	PCI address to convert
+ * @size:	Size of the addressrange
+ * @mask:	Mask of flags to match
+ * @flags:	Flags for the region type (PCI_REGION_...)
+ * Return: physical address corresponding to that PCI bus address range or 0 if
+ *	   the range could not be converted
+ */
+phys_addr_t dm_pci_bus_range_to_phys(struct udevice *dev, pci_addr_t bus_addr,
+				     size_t size, unsigned long mask,
+				     unsigned long flags);
+
 /**
  * dm_pci_phys_to_bus() - convert a physical address to a PCI bus address
  *
-- 
2.35.1.894.gb6a874cedc-goog