[SPARC64]: Move away from virtual page tables, part 1.

We now use the TSB hardware assist features of the UltraSPARC
MMUs.

SMP is currently knowingly broken, we need to find another place
to store the per-cpu base pointers.  We hid them away in the TSB
base register, and that obviously will not work any more :-)

Another known broken case is non-8KB base page size.

Also noticed that flush_tlb_all() is not referenced anywhere, only
the internal __flush_tlb_all() (local cpu only) is used by the
sparc64 port, so we can get rid of flush_tlb_all().

The kernel gets it's own 8KB TSB (swapper_tsb) and each address space
gets it's own private 8K TSB.  Later we can add code to dynamically
increase the size of per-process TSB as the RSS grows.  An 8KB TSB is
good enough for up to about a 4MB RSS, after which the TSB starts to
incur many capacity and conflict misses.

We even accumulate OBP translations into the kernel TSB.

Another area for refinement is large page size support.  We could use
a secondary address space TSB to handle those.

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

arch/sparc64/kernel/Makefile

@@ -38,5 +38,5 @@ else
   CMODEL_CFLAG := -m64 -mcmodel=medlow
 endif
 
-head.o: head.S ttable.S itlb_base.S dtlb_base.S dtlb_backend.S dtlb_prot.S \
+head.o: head.S ttable.S itlb_miss.S dtlb_miss.S ktlb.S tsb.S \
 	etrap.S rtrap.S winfixup.S entry.S

arch/sparc64/kernel/binfmt_aout32.c

@@ -31,6 +31,7 @@
 #include <asm/system.h>
 #include <asm/uaccess.h>
 #include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
 
 static int load_aout32_binary(struct linux_binprm *, struct pt_regs * regs);
 static int load_aout32_library(struct file*);
@@ -329,15 +330,9 @@ static int load_aout32_binary(struct linux_binprm * bprm, struct pt_regs * regs)
 
 	current->mm->start_stack =
 		(unsigned long) create_aout32_tables((char __user *)bprm->p, bprm);
-	if (!(orig_thr_flags & _TIF_32BIT)) {
-		unsigned long pgd_cache = get_pgd_cache(current->mm->pgd);
-
-		__asm__ __volatile__("stxa\t%0, [%1] %2\n\t"
-				     "membar #Sync"
-				     : /* no outputs */
-				     : "r" (pgd_cache),
-				       "r" (TSB_REG), "i" (ASI_DMMU));
-	}
+	tsb_context_switch(__pa(current->mm->pgd),
+	                   current->mm->context.sparc64_tsb);
+
 	start_thread32(regs, ex.a_entry, current->mm->start_stack);
 	if (current->ptrace & PT_PTRACED)
 		send_sig(SIGTRAP, current, 0);

arch/sparc64/kernel/dtlb_miss.S

@@ -0,0 +1,39 @@
+/* DTLB ** ICACHE line 1: Context 0 check and TSB load	*/
+	ldxa	[%g0] ASI_DMMU_TSB_8KB_PTR, %g1	! Get TSB 8K pointer
+	ldxa	[%g0] ASI_DMMU, %g6		! Get TAG TARGET
+	srlx	%g6, 48, %g5			! Get context
+	brz,pn	%g5, kvmap_dtlb			! Context 0 processing
+	 nop					! Delay slot (fill me)
+	ldda	[%g1] ASI_NUCLEUS_QUAD_LDD, %g4	! Load TSB entry
+	nop					! Push branch to next I$ line
+	cmp	%g4, %g6			! Compare TAG
+
+/* DTLB ** ICACHE line 2: TSB compare and TLB load	*/
+	bne,pn	%xcc, tsb_miss_dtlb		! Miss
+	 mov	FAULT_CODE_DTLB, %g3
+	stxa	%g5, [%g0] ASI_DTLB_DATA_IN	! Load TLB
+	retry					! Trap done
+	nop
+	nop
+	nop
+	nop
+
+/* DTLB ** ICACHE line 3:				*/
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+
+/* DTLB ** ICACHE line 4: 				*/
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop
+	nop

arch/sparc64/kernel/etrap.S

@@ -99,6 +99,7 @@ etrap_irq:
 		wrpr	%g0, ETRAP_PSTATE2, %pstate
 		mov	%l6, %g6
 #ifdef CONFIG_SMP
+#error IMMU TSB usage must be fixed
 		mov	TSB_REG, %g3
 		ldxa	[%g3] ASI_IMMU, %g5
 #endif
@@ -248,6 +249,7 @@ scetrap:	rdpr	%pil, %g2
 		mov	%l6, %g6
 		stx	%i7, [%sp + PTREGS_OFF + PT_V9_I7]
 #ifdef CONFIG_SMP
+#error IMMU TSB usage must be fixed
 		mov	TSB_REG, %g3
 		ldxa	[%g3] ASI_IMMU, %g5
 #endif