quoted

We need, some platforms pass NULL pointer as host bridge parent.

Yijing,

May I suggest a different approach here? Rather than having to pass an opaque
pointer that gets converted by the host bridge driver back to the private
structure, what about promoting a new style of usage, that is similar to the
way device drivers work? Lets try to promote the embedding of the generic
pci_host_bridge structure in the host bridge specific structure! Then we can
access the private data doing container_of().

Something like this:

struct pci_controller {
	struct pci_host_bridge bridge;
	/* private host bridge data here */
	.....
};

#define PCI_CONTROLLER(bus)	({
	struct pci_host_bridge *hb = to_pci_host_bridge(bus->bridge); \
	container_of(hb, struct pci_controller, bridge); })


Then we can retrieve the host bridge structure from everywhere we have a device.

Hi Liviu, it looks good to me, because this change will involve lots platforms,
I would think more about it. Thanks for your suggestion very much! :)


Thanks!
Yijing.

Best regards,
Liviu

quoted

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+	host = kzalloc(sizeof(*host), GFP_KERNEL);
+	if (!host)
+		return NULL;

devm_kzalloc maybe?

I don't know much detail about devm_kzalloc(), but we have no pci host driver
here, and I found no devm_kzalloc() uses in core PCI code before.

quoted

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+	if (!resources) {
+		/* Use default IO/MEM/BUS resources*/
+		pci_add_resource(&host->windows, &ioport_resource);
+		pci_add_resource(&host->windows, &iomem_resource);
+		pci_add_resource(&host->windows, &busn_resource);
+	} else {
+		list_for_each_entry_safe(window, n, resources, list)
+			list_move_tail(&window->list, &host->windows);
+	}

I think we should assume that the correct resources are passed. You
could add a wrapper around this function to convert old platforms
though.

OK, I will move these code out of pci_create_host_bridge, and add a wrapper
to setup the default resources.

quoted

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+EXPORT_SYMBOL(pci_create_host_bridge);

EXPORT_SYMBOL_GPL() maybe?

OK, will update it.

quoted

quoted

diff --git a/include/linux/pci.h b/include/linux/pci.h
index 8b11b38..daa7f40 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h

@@ -402,7 +402,12 @@ struct pci_host_bridge_window {
 struct pci_host_bridge {
 	struct device dev;
 	struct pci_bus *bus;		/* root bus */
+	struct list_head list;
 	struct list_head windows;	/* pci_host_bridge_windows */
+	int busnum;

The busnum should already be implied through the bus resource.

Yes, I will consider remove it and introduce a helper function to get the root bus number, thanks!

Thanks!
Yijing.

quoted

	Arnd

.

-- 
Thanks!
Yijing

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-- 
Thanks!
Yijing