[PATCH v9 11/26] PCI: Include fixed BARs into the bus size calculating

[Sergei Miroshnichenko <s.miroshnichenko@yadro.com>]

The only difference between fixed and movable BARs is a size and offset
preservation after they are released (the corresponding struct resource* is
detached from a bridge window for a while during a bus rescan). So fixed
BARs should not be skipped in pbus_size_{mem,io}().

Bridge window size calculation uses pci_{,sriov_}resource_alignment(), that
are applicable only to not yet assigned BARs and don't make sense for fixed
ones. Original alignment of a fixed BAR is lost after assignment, so return
1 in this case as a neutral value.

A window should be additionally extended if it has distant fixed BARs on
its edges:

    | <--          bridge window          --> |
    | **fixed BAR** |         | **fixed BAR** |

Signed-off-by: Sergei Miroshnichenko <s.miroshnichenko@yadro.com>
---
 drivers/pci/iov.c       |  2 ++
 drivers/pci/pci.h       |  2 ++
 drivers/pci/setup-bus.c | 21 ++++++++++++++++++++-
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/drivers/pci/iov.c b/drivers/pci/iov.c
index 4afd4ee4f7f0..f4f7c2702579 100644
--- a/drivers/pci/iov.c
+++ b/drivers/pci/iov.c
@@ -872,6 +872,8 @@ resource_size_t __weak pcibios_iov_resource_alignment(struct pci_dev *dev,
  */
 resource_size_t pci_sriov_resource_alignment(struct pci_dev *dev, int resno)
 {
+	if (pci_dev_bar_fixed(dev, dev->resource + resno))
+		return 1;
 	return pcibios_iov_resource_alignment(dev, resno);
 }
 
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index f47f80b6a620..f7460ddd196a 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -576,6 +576,8 @@ static inline resource_size_t pci_resource_alignment(struct pci_dev *dev,
 	if (resno >= PCI_IOV_RESOURCES && resno <= PCI_IOV_RESOURCE_END)
 		return pci_sriov_resource_alignment(dev, resno);
 #endif
+	if (pci_dev_bar_fixed(dev, res))
+		return 1;
 	if (dev->class >> 8 == PCI_CLASS_BRIDGE_CARDBUS)
 		return pci_cardbus_resource_alignment(res);
 	return resource_alignment(res);
diff --git a/drivers/pci/setup-bus.c b/drivers/pci/setup-bus.c
index 640090046ffd..3dadadea10d6 100644
--- a/drivers/pci/setup-bus.c
+++ b/drivers/pci/setup-bus.c
@@ -888,9 +888,15 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 	resource_size_t children_add_size = 0;
 	resource_size_t min_align, align;
 
+	struct resource *fixed_range;
+	resource_size_t fixed_size;
+
 	if (!b_res)
 		return;
 
+	fixed_range = &bus->fixed_range[0];
+	fixed_size = pci_fixed_range_valid(fixed_range) ? resource_size(fixed_range) : 0;
+
 	/* If resource is already assigned, nothing more to do */
 	if (b_res->parent)
 		return;
@@ -923,6 +929,9 @@ static void pbus_size_io(struct pci_bus *bus, resource_size_t min_size,
 		}
 	}
 
+	if (size1 < fixed_size)
+		size1 = fixed_size;
+
 	size0 = calculate_iosize(size, min_size, size1, 0, 0,
 			resource_size(b_res), min_align);
 	size1 = (!realloc_head || (realloc_head && !add_size && !children_add_size)) ? size0 :
@@ -1004,6 +1013,9 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 	resource_size_t children_add_size = 0;
 	resource_size_t children_add_align = 0;
 	resource_size_t add_align = 0;
+	int idx;
+	struct resource *fixed_range;
+	resource_size_t fixed_size;
 
 	if (!b_res)
 		return -ENOSPC;
@@ -1012,6 +1024,13 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 	if (b_res->parent)
 		return 0;
 
+	idx = pci_get_bridge_resource_idx(b_res);
+	fixed_range = &bus->fixed_range[idx];
+	fixed_size = pci_fixed_range_valid(fixed_range) ? resource_size(fixed_range) : 0;
+
+	if (min_size < fixed_size)
+		min_size = fixed_size;
+
 	memset(aligns, 0, sizeof(aligns));
 	max_order = 0;
 	size = 0;
@@ -1023,7 +1042,7 @@ static int pbus_size_mem(struct pci_bus *bus, unsigned long mask,
 			struct resource *r = &dev->resource[i];
 			resource_size_t r_size;
 
-			if (r->parent || (r->flags & IORESOURCE_PCI_FIXED) ||
+			if (r->parent ||
 			    !pci_dev_bar_enabled(dev, i) ||
 			    ((r->flags & mask) != type &&
 			     (r->flags & mask) != type2 &&
-- 
2.24.1