diff mbox

[v2,2/2] MIPS: PCI: Pass controller's resources to pci_create_bus() in pcibios_scanbus()

Message ID 1314271117-32717-3-git-send-email-dczhu@mips.com (mailing list archive)
State New, archived
Headers show

Commit Message

Deng-Cheng Zhu Aug. 25, 2011, 11:18 a.m. UTC
Use the new interface of pci_create_bus() so that system controller's
resources are added to the root bus upon bus creation, thereby avoiding
conflicts with PCI quirks before pcibios_fixup_bus() gets the chance to do
right things in pci_scan_child_bus(). Also, since we are passing resources
to pci_create_bus() and setting them up in the bus->resources list as
opposed to the bus->resource[] array, we have to adopt the list style while
doing bus fixups later on, or else, for example in this MIPS case, system
controller's resources will stay in both bus->resources and
bus->resource[].

Signed-off-by: Deng-Cheng Zhu <dczhu@mips.com>
---
Changes (v2 - v1):
o Merge [PATCH 1/3] to [PATCH 3/3] of v1.
o Add more info to patch description.

 arch/mips/pci/pci.c |   53 ++++++++++++++++++++++++++++++++++++++++++++++----
 1 files changed, 48 insertions(+), 5 deletions(-)

Comments

Bjorn Helgaas Aug. 25, 2011, 4:09 p.m. UTC | #1
On Thu, Aug 25, 2011 at 5:18 AM, Deng-Cheng Zhu <dczhu@mips.com> wrote:
> Use the new interface of pci_create_bus() so that system controller's
> resources are added to the root bus upon bus creation, thereby avoiding
> conflicts with PCI quirks before pcibios_fixup_bus() gets the chance to do
> right things in pci_scan_child_bus(). Also, since we are passing resources
> to pci_create_bus() and setting them up in the bus->resources list as
> opposed to the bus->resource[] array, we have to adopt the list style while
> doing bus fixups later on, or else, for example in this MIPS case, system
> controller's resources will stay in both bus->resources and
> bus->resource[].

> +static void __devinit
> +pcibios_setup_root_resources(struct pci_bus *bus, struct pci_controller *ctrl)
> +{
> +       pci_bus_remove_resources(bus);
> +       pci_bus_add_resource(bus, ctrl->io_resource, 0);
> +       pci_bus_add_resource(bus, ctrl->mem_resource, 0);
> +}
> +
>  void __devinit pcibios_fixup_bus(struct pci_bus *bus)
>  {
>        /* Propagate hose info into the subordinate devices.  */
> @@ -269,10 +313,9 @@ void __devinit pcibios_fixup_bus(struct pci_bus *bus)
>        struct list_head *ln;
>        struct pci_dev *dev = bus->self;
>
> -       if (!dev) {
> -               bus->resource[0] = hose->io_resource;
> -               bus->resource[1] = hose->mem_resource;
> -       } else if (pci_probe_only &&
> +       if (!dev)
> +               pcibios_setup_root_resources(bus, hose);

As I mentioned in my other response, I think you can just drop this
whole "if (!dev)" block since the root bus resources should already be
correct.  There's no need to move them from the bus->resource[] array
to the bus->resources list.

Someday, if all arches adopt your nice pci_create_bus() extension to
make root bus resources correct from the beginning, there should be no
arch references to the bus->resource[] array left, and then we can
remove it altogether.  At least, that's what I was hoping when I added
the list :)

In any case, all the *readers* of bus resources already use the
pci_bus_for_each_resource() interface, which knows how to look at both
the array and the list.

Bjorn
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diff mbox

Patch

diff --git a/arch/mips/pci/pci.c b/arch/mips/pci/pci.c
index 33bba7b..30856d6 100644
--- a/arch/mips/pci/pci.c
+++ b/arch/mips/pci/pci.c
@@ -76,11 +76,41 @@  pcibios_align_resource(void *data, const struct resource *res,
 	return start;
 }
 
+static struct pci_bus_resource *
+controller_resources(const struct pci_controller *ctrl)
+{
+	struct pci_bus_resource *mem_res, *io_res;
+
+	mem_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
+	if (!mem_res)
+		goto err_out;
+
+	mem_res->res = ctrl->mem_resource;
+	mem_res->flags = 0;
+	INIT_LIST_HEAD(&mem_res->list);
+
+	io_res = kzalloc(sizeof(struct pci_bus_resource), GFP_KERNEL);
+	if (!io_res) {
+		kfree(mem_res);
+		goto err_out;
+	}
+
+	io_res->res = ctrl->io_resource;
+	io_res->flags = 0;
+	list_add(&io_res->list, &mem_res->list);
+
+	return mem_res;
+err_out:
+	printk(KERN_ERR "Can't allocate PCI bus resource.\n");
+	return NULL;
+}
+
 static void __devinit pcibios_scanbus(struct pci_controller *hose)
 {
 	static int next_busno;
 	static int need_domain_info;
 	struct pci_bus *bus;
+	struct pci_bus_resource *bus_res;
 
 	if (!hose->iommu)
 		PCI_DMA_BUS_IS_PHYS = 1;
@@ -88,7 +118,13 @@  static void __devinit pcibios_scanbus(struct pci_controller *hose)
 	if (hose->get_busno && pci_probe_only)
 		next_busno = (*hose->get_busno)();
 
-	bus = pci_scan_bus(next_busno, hose->pci_ops, hose);
+	bus_res = controller_resources(hose);
+	bus = pci_create_bus(NULL, next_busno, hose->pci_ops, hose, bus_res);
+	if (bus) {
+		bus->subordinate = pci_scan_child_bus(bus);
+		pci_bus_add_devices(bus);
+	}
+
 	hose->bus = bus;
 
 	need_domain_info = need_domain_info || hose->index;
@@ -261,6 +297,14 @@  static void pcibios_fixup_device_resources(struct pci_dev *dev,
 	}
 }
 
+static void __devinit
+pcibios_setup_root_resources(struct pci_bus *bus, struct pci_controller *ctrl)
+{
+	pci_bus_remove_resources(bus);
+	pci_bus_add_resource(bus, ctrl->io_resource, 0);
+	pci_bus_add_resource(bus, ctrl->mem_resource, 0);
+}
+
 void __devinit pcibios_fixup_bus(struct pci_bus *bus)
 {
 	/* Propagate hose info into the subordinate devices.  */
@@ -269,10 +313,9 @@  void __devinit pcibios_fixup_bus(struct pci_bus *bus)
 	struct list_head *ln;
 	struct pci_dev *dev = bus->self;
 
-	if (!dev) {
-		bus->resource[0] = hose->io_resource;
-		bus->resource[1] = hose->mem_resource;
-	} else if (pci_probe_only &&
+	if (!dev)
+		pcibios_setup_root_resources(bus, hose);
+	else if (pci_probe_only &&
 		   (dev->class >> 8) == PCI_CLASS_BRIDGE_PCI) {
 		pci_read_bridge_bases(bus);
 		pcibios_fixup_device_resources(dev, bus);