[SPARC64]: Fix conflicts in SBUS/PCI/EBUS/ISA DMA handling.

Fully unify all of the DMA ops so that subordinate bus types to
the DMA operation providers (such as ebus, isa, of_device) can
work transparently.

Basically, we just make sure that for every system device we
create, the dev->archdata 'iommu' and 'stc' fields are filled
in.

Then we have two platform variants of the DMA ops, one for SUN4U which
actually programs the real hardware, and one for SUN4V which makes
hypervisor calls.

This also fixes the crashes in parport_pc on sparc64, reported by
Meelis Roos.

Signed-off-by: David S. Miller <davem@davemloft.net>

arch/sparc64/kernel/Makefile

@@ -8,14 +8,14 @@ EXTRA_CFLAGS := -Werror
 extra-y		:= head.o init_task.o vmlinux.lds
 
 obj-y		:= process.o setup.o cpu.o idprom.o \
-		   traps.o auxio.o una_asm.o sysfs.o \
+		   traps.o auxio.o una_asm.o sysfs.o iommu.o \
 		   irq.o ptrace.o time.o sys_sparc.o signal.o \
 		   unaligned.o central.o pci.o starfire.o semaphore.o \
 		   power.o sbus.o iommu_common.o sparc64_ksyms.o chmc.o \
 		   visemul.o prom.o of_device.o hvapi.o sstate.o mdesc.o
 
 obj-$(CONFIG_STACKTRACE) += stacktrace.o
-obj-$(CONFIG_PCI)	 += ebus.o isa.o pci_common.o pci_iommu.o \
+obj-$(CONFIG_PCI)	 += ebus.o isa.o pci_common.o \
 			    pci_psycho.o pci_sabre.o pci_schizo.o \
 			    pci_sun4v.o pci_sun4v_asm.o pci_fire.o
 obj-$(CONFIG_SMP)	 += smp.o trampoline.o hvtramp.o

arch/sparc64/kernel/ebus.c

@@ -391,6 +391,8 @@ static void __init fill_ebus_device(struct device_node *dp, struct linux_ebus_de
 	sd = &dev->ofdev.dev.archdata;
 	sd->prom_node = dp;
 	sd->op = &dev->ofdev;
+	sd->iommu = dev->bus->ofdev.dev.parent->archdata.iommu;
+	sd->stc = dev->bus->ofdev.dev.parent->archdata.stc;
 
 	dev->ofdev.node = dp;
 	dev->ofdev.dev.parent = &dev->bus->ofdev.dev;