Commit 0c5be0cb authored Feb 23, 2012 by Yinghai Lu Committed by Jesse Barnes Feb 24, 2012

PCI: Retry on IORESOURCE_IO type allocations

When enabling pci reallocation for a pci bridge, we clear the small size
in in bridge and re-assign with requested + optional size for first
several tries, but Ram mention could have problem with one case:
https://bugzilla.kernel.org/show_bug.cgi?id=15960

After checking the booting log in
https://lkml.org/lkml/2010/4/19/44

[regression, bisected] Xonar DX invalid PCI I/O range since 977d17bb

We should not stop too early for io ports.
Apr 19 10:19:38 [kernel] pci 0000:04:00.0: BAR 7: can't assign io (size 0x4000)
Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 8: assigned [mem 0x80400000-0x805fffff]
Apr 19 10:19:38 [kernel] pci 0000:05:01.0: BAR 7: can't assign io (size 0x2000)
Apr 19 10:19:38 [kernel] pci 0000:05:02.0: BAR 7: can't assign io (size 0x1000)
Apr 19 10:19:38 [kernel] pci 0000:05:03.0: BAR 7: can't assign io (size 0x1000)
Apr 19 10:19:38 [kernel] pci 0000:08:00.0: BAR 7: can't assign io (size 0x1000)
Apr 19 10:19:38 [kernel] pci 0000:09:04.0: BAR 0: can't assign io (size 0x100)
and clear 00:1c.0 to retry again.

This patch removes IORESOUCE_IO checking, and tries one more time. It
gives us a chance to get an allocation for the 00:1c.0 io port range
because the range from 0x4000 to 0x8000 will be freed and we can use it.

Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>

parent 823806ff

drivers/pci/setup-bus.c

+1 −11

Original line number	Diff line number	Diff line
		@@ -1292,7 +1292,6 @@ pci_assign_unassigned_resources(void)
		struct pci_dev_resource *fail_res;
		unsigned long type_mask = IORESOURCE_IO \| IORESOURCE_MEM \|
		IORESOURCE_PREFETCH;
		unsigned long failed_type;
		int pci_try_num = 1;

		/* don't realloc if asked to do so */
		@@ -1327,16 +1326,7 @@ again:
		if (list_empty(&fail_head))
		goto enable_and_dump;

		failed_type = 0;
		list_for_each_entry(fail_res, &fail_head, list)
		failed_type \|= fail_res->flags;

		/*
		* io port are tight, don't try extra
		* or if reach the limit, don't want to try more
		*/
		failed_type &= type_mask;
		if ((failed_type == IORESOURCE_IO) \|\| (tried_times >= pci_try_num)) {
		if (tried_times >= pci_try_num) {
		free_list(&fail_head);
		goto enable_and_dump;
		}

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