We utilize the IOMMU_INIT macros to create this dependency:

               [null]
                 |
       [pci_xen_swiotlb_detect]
                 |
       [pci_swiotlb_detect_override]
                 |
       [pci_swiotlb_detect_4gb]
                 |
         +-------+--------+
        /                  \
[detect_calgary]    [gart_iommu_hole_init]
                            |
                    [amd_iommu_detect]

Meaning that 'amd_iommu_detect' will be called after
'gart_iommu_hole_init'.
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
LKML-Reference: <1282845485-8991-9-git-send-email-konrad.wilk@oracle.com>
CC: Fujita Tomonori <fujita.tomonori@lab.ntt.co.jp>
CC: Joerg Roedel <joerg.roedel@amd.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Ingo Molnar <mingo@redhat.com>
Signed-off-by: NH. Peter Anvin <hpa@linux.intel.com>