From: Kei Tokunaga <ktokunag@redhat.com>
Subject: [RHEL5.1 PATCH] Cannot use e100 and IDE controller on Xen-ia64
Date: Wed, 08 Aug 2007 12:05:06 -0400
Bugzilla: 250454
Message-Id: <46B9E9B2.3020901@redhat.com>
Changelog: [XEN] ia64: Cannot use e100 and IDE controller


bz250454
https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=250454

Dom0 fails to detect e100 and IDE controller since io_tlb_end
was out of bounds, which caused swiotlb_dma_supported() to fail.

This are spews of failure of probing e100:

  e100: Intel(R) PRO/100 Network Driver, 3.5.10-k2-NAPI
  e100: Copyright(c) 1999-2005 Intel Corporation
  GSI 20 (level, low) -> CPU 2 (0x0200) vector 51
  ACPI: PCI Interrupt 0000:01:08.0[A] -> GSI 20 (level, low) -> IRQ 51
  e100: 0000:01:08.0: e100_probe: No usable DMA configuration, aborting.
  ACPI: PCI interrupt for device 0000:01:08.0 disabled
  GSI 20 (level, low) -> CPU 2 (0x0200) vector 51 unregistered
  e100: probe of 0000:01:08.0 failed with error -5

The fix-patch is upstream:
  http://xenbits.xensource.com/ext/ia64/linux-2.6.18-xen.hg?rev/b3ac98591e60

Attached patch applies to -38.  We have verified that it worked on -37.

Thanks,
Kei

---

 linux-2.6.18.ia64-kei/arch/ia64/xen/swiotlb.c |    4 ++++
 1 file changed, 4 insertions(+)

diff -puN arch/ia64/xen/swiotlb.c~bz250454 arch/ia64/xen/swiotlb.c
--- linux-2.6.18.ia64/arch/ia64/xen/swiotlb.c~bz250454	2007-08-08 10:39:13.000000000 -0400
+++ linux-2.6.18.ia64-kei/arch/ia64/xen/swiotlb.c	2007-08-08 10:39:27.000000000 -0400
@@ -862,7 +862,11 @@ swiotlb_dma_mapping_error(dma_addr_t dma
 int
 swiotlb_dma_supported (struct device *hwdev, u64 mask)
 {
+#ifdef CONFIG_XEN
+	return (virt_to_bus(io_tlb_end - 1)) <= mask;
+#else
 	return (virt_to_bus(io_tlb_end) - 1) <= mask;
+#endif
 }
 
 EXPORT_SYMBOL(swiotlb_init);

_