ia64: rework iommu probing

ia64 currently organizes the iommu probing along machves, which isn't
very helpful.  Instead just try to probe for Intel IOMMUs in mem_init
as they are properly described in ACPI and if none was found initialize
the swiotlb buffer.  The HP SBA handling is then only done delayed when
the actual hardware is probed. Only in the case that we actually found
usable IOMMUs we then set up the DMA ops and free the not needed
swiotlb buffer.  This scheme gets rid of the need for the dma_init
machvec operation, and the dig_vtd machvec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lkml.kernel.org/r/20190813072514.23299-24-hch@lst.de
Signed-off-by: Tony Luck <tony.luck@intel.com>

3 files changed, 0 insertions, 42 deletions

diff --git a/arch/ia64/kernel/acpi.c b/arch/ia64/kernel/acpi.c
index a63e472f5317..644f34e4342e 100644
--- a/arch/ia64/kernel/acpi.c
+++ b/arch/ia64/kernel/acpi.c
@@ -65,9 +65,6 @@ acpi_get_sysname(void)
 	struct acpi_table_rsdp *rsdp;
 	struct acpi_table_xsdt *xsdt;
 	struct acpi_table_header *hdr;
-#ifdef CONFIG_INTEL_IOMMU
-	u64 i, nentries;
-#endif
 
 	rsdp_phys = acpi_find_rsdp();
 	if (!rsdp_phys) {
@@ -98,18 +95,6 @@ acpi_get_sysname(void)
 			return "uv";
 	}
 
-#ifdef CONFIG_INTEL_IOMMU
-	/* Look for Intel IOMMU */
-	nentries = (hdr->length - sizeof(*hdr)) /
-			 sizeof(xsdt->table_offset_entry[0]);
-	for (i = 0; i < nentries; i++) {
-		hdr = __va(xsdt->table_offset_entry[i]);
-		if (strncmp(hdr->signature, ACPI_SIG_DMAR,
-			sizeof(ACPI_SIG_DMAR) - 1) == 0)
-			return "dig_vtd";
-	}
-#endif
-
 	return "dig";
 }
 #endif /* CONFIG_IA64_GENERIC */
diff --git a/arch/ia64/kernel/dma-mapping.c b/arch/ia64/kernel/dma-mapping.c
index 4be5ee04ccfa..53aaa8597920 100644
--- a/arch/ia64/kernel/dma-mapping.c
+++ b/arch/ia64/kernel/dma-mapping.c
@@ -1,6 +1,5 @@
 // SPDX-License-Identifier: GPL-2.0
 #include <linux/dma-direct.h>
-#include <linux/swiotlb.h>
 #include <linux/export.h>
 
 /* Set this to 1 if there is a HW IOMMU in the system */
@@ -27,9 +26,4 @@ long arch_dma_coherent_to_pfn(struct device *dev, void *cpu_addr,
 {
 	return page_to_pfn(virt_to_page(cpu_addr));
 }
-
-void __init swiotlb_dma_init(void)
-{
-	swiotlb_init(1);
-}
 #endif
diff --git a/arch/ia64/kernel/pci-dma.c b/arch/ia64/kernel/pci-dma.c
index fe988c49f01c..c5a8df9e77d0 100644
--- a/arch/ia64/kernel/pci-dma.c
+++ b/arch/ia64/kernel/pci-dma.c
@@ -34,24 +34,3 @@ static int __init pci_iommu_init(void)
 
 /* Must execute after PCI subsystem */
 fs_initcall(pci_iommu_init);
-
-void __init pci_iommu_alloc(void)
-{
-	/*
-	 * The order of these functions is important for
-	 * fall-back/fail-over reasons
-	 */
-	detect_intel_iommu();
-
-#ifdef CONFIG_SWIOTLB
-	if (!iommu_detected) {
-#ifdef CONFIG_IA64_GENERIC
-		printk(KERN_INFO "PCI-DMA: Re-initialize machine vector.\n");
-		machvec_init("dig");
-		swiotlb_dma_init();
-#else
-		panic("Unable to find Intel IOMMU");
-#endif /* CONFIG_IA64_GENERIC */
-	}
-#endif /* CONFIG_SWIOTLB */
-}