[IA64-SGI] - Eliminate SN pio_phys_xxx macros. Move to assembly

Rewrite the SN pio_phys_xxx macros in assembly language. This
avoids issues with the Intel icc compiler. Function call
overhead is not an issue - the functions reference PIOs
and take 100's nsec to complete.

In addition, the functions should likely be in assembly
language anyway - they reference memory using physical
addressing mode. One function executes with psr.ic disabled.

Signed-off-by: Jack Steiner <steiner@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

arch/ia64/sn/kernel/pio_phys.S

@@ -0,0 +1,71 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 2000-2005 Silicon Graphics, Inc. All rights reserved.
+ *
+ * This file contains macros used to access MMR registers via
+ * uncached physical addresses.
+ *      pio_phys_read_mmr  - read an MMR
+ *      pio_phys_write_mmr - write an MMR
+ *      pio_atomic_phys_write_mmrs - atomically write 1 or 2 MMRs with psr.ic=0
+ *              Second MMR will be skipped if address is NULL
+ *
+ * Addresses passed to these routines should be uncached physical addresses
+ * 	ie., 0x80000....
+ */
+
+
+
+#include <asm/asmmacro.h>
+#include <asm/page.h>
+
+GLOBAL_ENTRY(pio_phys_read_mmr)
+	.prologue
+	.regstk 1,0,0,0
+	.body
+	mov r2=psr
+	rsm psr.i | psr.dt
+	;;
+	srlz.d
+	ld8.acq r8=[r32]
+	;;
+	mov psr.l=r2;;
+	srlz.d
+	br.ret.sptk.many rp
+END(pio_phys_read_mmr)
+
+GLOBAL_ENTRY(pio_phys_write_mmr)
+	.prologue
+	.regstk 2,0,0,0
+	.body
+	mov r2=psr
+	rsm psr.i | psr.dt
+	;;
+	srlz.d
+	st8.rel [r32]=r33
+	;;
+	mov psr.l=r2;;
+	srlz.d
+	br.ret.sptk.many rp
+END(pio_phys_write_mmr)
+
+GLOBAL_ENTRY(pio_atomic_phys_write_mmrs)
+	.prologue
+	.regstk 4,0,0,0
+	.body
+	mov r2=psr
+	cmp.ne p9,p0=r34,r0;
+	rsm psr.i | psr.dt | psr.ic
+	;;
+	srlz.d
+	st8.rel [r32]=r33
+(p9)	st8.rel [r34]=r35
+	;;
+	mov psr.l=r2;;
+	srlz.d
+	br.ret.sptk.many rp
+END(pio_atomic_phys_write_mmrs)
+
+