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[IA64-SGI] - Eliminate SN pio_phys_xxx macros. Move to assembly
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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>
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Jack Steiner authored and Tony Luck committed Feb 7, 2006
1 parent 412e6a3 commit dcc1dd2
Showing 3 changed files with 78 additions and 52 deletions.
3 changes: 2 additions & 1 deletion arch/ia64/sn/kernel/Makefile
Original file line number Diff line number Diff line change
@@ -10,7 +10,8 @@
CPPFLAGS += -I$(srctree)/arch/ia64/sn/include

obj-y += setup.o bte.o bte_error.o irq.o mca.o idle.o \
huberror.o io_init.o iomv.o klconflib.o sn2/
huberror.o io_init.o iomv.o klconflib.o pio_phys.o \
sn2/
obj-$(CONFIG_IA64_GENERIC) += machvec.o
obj-$(CONFIG_SGI_TIOCX) += tiocx.o
obj-$(CONFIG_IA64_SGI_SN_XP) += xp.o
71 changes: 71 additions & 0 deletions arch/ia64/sn/kernel/pio_phys.S
Original file line number Diff line number Diff line change
@@ -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)


56 changes: 5 additions & 51 deletions include/asm-ia64/sn/rw_mmr.h
Original file line number Diff line number Diff line change
@@ -3,15 +3,14 @@
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*
* Copyright (C) 2002-2004 Silicon Graphics, Inc. All Rights Reserved.
* Copyright (C) 2002-2006 Silicon Graphics, Inc. All Rights Reserved.
*/
#ifndef _ASM_IA64_SN_RW_MMR_H
#define _ASM_IA64_SN_RW_MMR_H


/*
* This file contains macros used to access MMR registers via
* uncached physical addresses.
* This file that access MMRs 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
@@ -22,53 +21,8 @@
*/


extern inline long
pio_phys_read_mmr(volatile long *mmr)
{
long val;
asm volatile
("mov r2=psr;;"
"rsm psr.i | psr.dt;;"
"srlz.i;;"
"ld8.acq %0=[%1];;"
"mov psr.l=r2;;"
"srlz.i;;"
: "=r"(val)
: "r"(mmr)
: "r2");
return val;
}



extern inline void
pio_phys_write_mmr(volatile long *mmr, long val)
{
asm volatile
("mov r2=psr;;"
"rsm psr.i | psr.dt;;"
"srlz.i;;"
"st8.rel [%0]=%1;;"
"mov psr.l=r2;;"
"srlz.i;;"
:: "r"(mmr), "r"(val)
: "r2", "memory");
}

extern inline void
pio_atomic_phys_write_mmrs(volatile long *mmr1, long val1, volatile long *mmr2, long val2)
{
asm volatile
("mov r2=psr;;"
"rsm psr.i | psr.dt | psr.ic;;"
"cmp.ne p9,p0=%2,r0;"
"srlz.i;;"
"st8.rel [%0]=%1;"
"(p9) st8.rel [%2]=%3;;"
"mov psr.l=r2;;"
"srlz.i;;"
:: "r"(mmr1), "r"(val1), "r"(mmr2), "r"(val2)
: "p9", "r2", "memory");
}
extern long pio_phys_read_mmr(volatile long *mmr);
extern void pio_phys_write_mmr(volatile long *mmr, long val);
extern void pio_atomic_phys_write_mmrs(volatile long *mmr1, long val1, volatile long *mmr2, long val2);

#endif /* _ASM_IA64_SN_RW_MMR_H */

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