Fixes the problem of SCSI midlayer trying to bounce buffers
for memory above 4GB.

Signed-off-by: Grant Grundler <grundler@parisc-linux.org>

Index: arch/parisc/kernel/setup.c
===================================================================
RCS file: /var/cvs/linux-2.6/arch/parisc/kernel/setup.c,v
retrieving revision 1.9
diff -u -p -r1.9 setup.c
--- arch/parisc/kernel/setup.c	12 Oct 2004 01:07:00 -0000	1.9
+++ arch/parisc/kernel/setup.c	17 Nov 2004 04:24:00 -0000
@@ -53,6 +53,10 @@ struct proc_dir_entry * proc_runway_root
 struct proc_dir_entry * proc_gsc_root = NULL;
 struct proc_dir_entry * proc_mckinley_root = NULL;
 
+#if !defined(CONFIG_PA20) && (defined(CONFIG_IOMMU_CCIO) || defined(CONFIG_IOMMU_SBA))
+int parisc_bus_is_phys = TRUE;	/* Assume no IOMMU is present */
+EXPORT_SYMBOL(parisc_bus_is_phys);
+#endif
 
 void __init setup_cmdline(char **cmdline_p)
 {
Index: drivers/parisc/ccio-dma.c
===================================================================
RCS file: /var/cvs/linux-2.6/drivers/parisc/ccio-dma.c,v
retrieving revision 1.16
diff -u -p -r1.16 ccio-dma.c
--- drivers/parisc/ccio-dma.c	26 Oct 2004 19:52:46 -0000	1.16
+++ drivers/parisc/ccio-dma.c	16 Nov 2004 18:59:35 -0000
@@ -1557,9 +1557,12 @@ static int ccio_probe(struct parisc_devi
 		create_proc_read_entry(MODULE_NAME"-bitmap", S_IRWXU,
 				       proc_runway_root, ccio_resource_map, NULL);
 	}
+
+	ioc_count++;
+
 	parisc_vmerge_boundary = IOVP_SIZE;
 	parisc_vmerge_max_size = BITS_PER_LONG * IOVP_SIZE;
-	ioc_count++;
+	parisc_has_iommu();
 	return 0;
 }
 
Index: drivers/parisc/sba_iommu.c
===================================================================
RCS file: /var/cvs/linux-2.6/drivers/parisc/sba_iommu.c,v
retrieving revision 1.21
diff -u -p -r1.21 sba_iommu.c
--- drivers/parisc/sba_iommu.c	9 Nov 2004 20:28:33 -0000	1.21
+++ drivers/parisc/sba_iommu.c	16 Nov 2004 19:04:40 -0000
@@ -880,17 +880,21 @@ sba_mark_invalid(struct ioc *ioc, dma_ad
  *
  * See Documentation/DMA-mapping.txt
  */
-static int
-sba_dma_supported( struct device *dev, u64 mask)
+static int sba_dma_supported( struct device *dev, u64 mask)
 {
+	struct ioc *ioc;
 	if (dev == NULL) {
 		printk(KERN_ERR MODULE_NAME ": EISA/ISA/et al not supported\n");
 		BUG();
 		return(0);
 	}
 
-	/* only support 32-bit PCI devices - no DAC support (yet) */
-	return((int) (mask == 0xffffffffUL));
+	ioc = GET_IOC(dev);
+
+	/* check if mask is > than the largest IO Virt Address */
+
+	return((int) (mask >= (ioc->ibase +
+				(ioc->pdir_size / sizeof(u64) * IOVP_SIZE) )));
 }
 
 
@@ -2113,7 +2117,7 @@ sba_driver_callback(struct parisc_device
 #endif
 	parisc_vmerge_boundary = IOVP_SIZE;
 	parisc_vmerge_max_size = IOVP_SIZE * BITS_PER_LONG;
-
+	parisc_has_iommu();
 	return 0;
 }
 
Index: include/asm-parisc/pci.h
===================================================================
RCS file: /var/cvs/linux-2.6/include/asm-parisc/pci.h,v
retrieving revision 1.12
diff -u -p -r1.12 pci.h
--- include/asm-parisc/pci.h	3 Nov 2004 00:57:50 -0000	1.12
+++ include/asm-parisc/pci.h	16 Nov 2004 18:55:42 -0000
@@ -106,11 +106,27 @@ static __inline__  int pci_is_lmmio(stru
 struct pci_bus;
 struct pci_dev;
 
-/* The PCI address space does equal the physical memory
- * address space.  The networking and block device layers use
+/*
+ * If the PCI device's view of memory is the same as the CPU's view of memory,
+ * PCI_DMA_BUS_IS_PHYS is true.  The networking and block device layers use
  * this boolean for bounce buffer decisions.
  */
-#define PCI_DMA_BUS_IS_PHYS     (1)
+#ifdef CONFIG_PA20
+/* All PA-2.0 machines have an IOMMU. */
+#define PCI_DMA_BUS_IS_PHYS	0
+#define parisc_has_iommu()	do { } while (0)
+#else
+
+#if defined(CONFIG_IOMMU_CCIO) || defined(CONFIG_IOMMU_SBA)
+#define PCI_DMA_BUS_IS_PHYS	parisc_bus_is_phys
+#define parisc_has_iommu()	do { parisc_bus_is_phys = 1; } while (0)
+#else
+#define PCI_DMA_BUS_IS_PHYS	1
+#define parisc_has_iommu()	do { } while (0)
+#endif
+
+#endif	/* !CONFIG_PA20 */
+
 
 /*
 ** Most PCI devices (eg Tulip, NCR720) also export the same registers