[deliverable/linux.git] / arch / parisc / lib / memcpy.c

/*
 *    Optimized memory copy routines.
 *
 *    Copyright (C) 2004 Randolph Chung <tausq@debian.org>
 *
 *    This program is free software; you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation; either version 2, or (at your option)
 *    any later version.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with this program; if not, write to the Free Software
 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *    Portions derived from the GNU C Library
 *    Copyright (C) 1991, 1997, 2003 Free Software Foundation, Inc.
 *
 * Several strategies are tried to try to get the best performance for various
 * conditions. In the optimal case, we copy 64-bytes in an unrolled loop using 
 * fp regs. This is followed by loops that copy 32- or 16-bytes at a time using
 * general registers.  Unaligned copies are handled either by aligning the 
 * destination and then using shift-and-write method, or in a few cases by 
 * falling back to a byte-at-a-time copy.
 *
 * I chose to implement this in C because it is easier to maintain and debug,
 * and in my experiments it appears that the C code generated by gcc (3.3/3.4
 * at the time of writing) is fairly optimal. Unfortunately some of the 
 * semantics of the copy routine (exception handling) is difficult to express
 * in C, so we have to play some tricks to get it to work.
 *
 * All the loads and stores are done via explicit asm() code in order to use
 * the right space registers. 
 * 
 * Testing with various alignments and buffer sizes shows that this code is 
 * often >10x faster than a simple byte-at-a-time copy, even for strangely
 * aligned operands. It is interesting to note that the glibc version
 * of memcpy (written in C) is actually quite fast already. This routine is 
 * able to beat it by 30-40% for aligned copies because of the loop unrolling, 
 * but in some cases the glibc version is still slightly faster. This lends 
 * more credibility that gcc can generate very good code as long as we are 
 * careful.
 *
 * TODO:
 * - cache prefetching needs more experimentation to get optimal settings
 * - try not to use the post-increment address modifiers; they create additional
 *   interlocks
 * - replace byte-copy loops with stybs sequences
 */

#ifdef __KERNEL__
#include <linux/module.h>
#include <linux/compiler.h>
#include <asm/uaccess.h>
#define s_space "%%sr1"
#define d_space "%%sr2"
#else
#include "memcpy.h"
#define s_space "%%sr0"
#define d_space "%%sr0"
#define pa_memcpy new2_copy
#endif

DECLARE_PER_CPU(struct exception_data, exception_data);

#define preserve_branch(label)	do {					\
	volatile int dummy;						\
	/* The following branch is never taken, it's just here to  */	\
	/* prevent gcc from optimizing away our exception code. */ 	\
	if (unlikely(dummy != dummy))					\
		goto label;						\
} while (0)

#define get_user_space() (segment_eq(get_fs(), KERNEL_DS) ? 0 : mfsp(3))
#define get_kernel_space() (0)

#define MERGE(w0, sh_1, w1, sh_2)  ({					\
	unsigned int _r;						\
	asm volatile (							\
	"mtsar %3\n"							\
	"shrpw %1, %2, %%sar, %0\n"					\
	: "=r"(_r)							\
	: "r"(w0), "r"(w1), "r"(sh_2)					\
	);								\
	_r;								\
})
#define THRESHOLD	16

#ifdef DEBUG_MEMCPY
#define DPRINTF(fmt, args...) do { printk(KERN_DEBUG "%s:%d:%s ", __FILE__, __LINE__, __func__ ); printk(KERN_DEBUG fmt, ##args ); } while (0)
#else
#define DPRINTF(fmt, args...)
#endif

#define def_load_ai_insn(_insn,_sz,_tt,_s,_a,_t,_e)	\
	__asm__ __volatile__ (				\
	"1:\t" #_insn ",ma " #_sz "(" _s ",%1), %0\n\t"	\
	ASM_EXCEPTIONTABLE_ENTRY(1b,_e)			\
	: _tt(_t), "+r"(_a)				\
	: 						\
	: "r8")

#define def_store_ai_insn(_insn,_sz,_tt,_s,_a,_t,_e) 	\
	__asm__ __volatile__ (				\
	"1:\t" #_insn ",ma %1, " #_sz "(" _s ",%0)\n\t"	\
	ASM_EXCEPTIONTABLE_ENTRY(1b,_e)			\
	: "+r"(_a) 					\
	: _tt(_t)					\
	: "r8")

#define ldbma(_s, _a, _t, _e) def_load_ai_insn(ldbs,1,"=r",_s,_a,_t,_e)
#define stbma(_s, _t, _a, _e) def_store_ai_insn(stbs,1,"r",_s,_a,_t,_e)
#define ldwma(_s, _a, _t, _e) def_load_ai_insn(ldw,4,"=r",_s,_a,_t,_e)
#define stwma(_s, _t, _a, _e) def_store_ai_insn(stw,4,"r",_s,_a,_t,_e)
#define flddma(_s, _a, _t, _e) def_load_ai_insn(fldd,8,"=f",_s,_a,_t,_e)
#define fstdma(_s, _t, _a, _e) def_store_ai_insn(fstd,8,"f",_s,_a,_t,_e)

#define def_load_insn(_insn,_tt,_s,_o,_a,_t,_e) 	\
	__asm__ __volatile__ (				\
	"1:\t" #_insn " " #_o "(" _s ",%1), %0\n\t"	\
	ASM_EXCEPTIONTABLE_ENTRY(1b,_e)			\
	: _tt(_t) 					\
	: "r"(_a)					\
	: "r8")

#define def_store_insn(_insn,_tt,_s,_t,_o,_a,_e) 	\
	__asm__ __volatile__ (				\
	"1:\t" #_insn " %0, " #_o "(" _s ",%1)\n\t" 	\
	ASM_EXCEPTIONTABLE_ENTRY(1b,_e)			\
	: 						\
	: _tt(_t), "r"(_a)				\
	: "r8")

#define ldw(_s,_o,_a,_t,_e)	def_load_insn(ldw,"=r",_s,_o,_a,_t,_e)
#define stw(_s,_t,_o,_a,_e) 	def_store_insn(stw,"r",_s,_t,_o,_a,_e)

#ifdef  CONFIG_PREFETCH
static inline void prefetch_src(const void *addr)
{
	__asm__("ldw 0(" s_space ",%0), %%r0" : : "r" (addr));
}

static inline void prefetch_dst(const void *addr)
{
	__asm__("ldd 0(" d_space ",%0), %%r0" : : "r" (addr));
}
#else
#define prefetch_src(addr) do { } while(0)
#define prefetch_dst(addr) do { } while(0)
#endif

/* Copy from a not-aligned src to an aligned dst, using shifts. Handles 4 words
 * per loop.  This code is derived from glibc. 
 */
static inline unsigned long copy_dstaligned(unsigned long dst, unsigned long src, unsigned long len, unsigned long o_dst, unsigned long o_src, unsigned long o_len)
{
	/* gcc complains that a2 and a3 may be uninitialized, but actually
	 * they cannot be.  Initialize a2/a3 to shut gcc up.
	 */
	register unsigned int a0, a1, a2 = 0, a3 = 0;
	int sh_1, sh_2;
	struct exception_data *d;

	/* prefetch_src((const void *)src); */

	/* Calculate how to shift a word read at the memory operation
	   aligned srcp to make it aligned for copy.  */
	sh_1 = 8 * (src % sizeof(unsigned int));
	sh_2 = 8 * sizeof(unsigned int) - sh_1;

	/* Make src aligned by rounding it down.  */
	src &= -sizeof(unsigned int);

	switch (len % 4)
	{
		case 2:
			/* a1 = ((unsigned int *) src)[0];
			   a2 = ((unsigned int *) src)[1]; */
			ldw(s_space, 0, src, a1, cda_ldw_exc);
			ldw(s_space, 4, src, a2, cda_ldw_exc);
			src -= 1 * sizeof(unsigned int);
			dst -= 3 * sizeof(unsigned int);
			len += 2;
			goto do1;
		case 3:
			/* a0 = ((unsigned int *) src)[0];
			   a1 = ((unsigned int *) src)[1]; */
			ldw(s_space, 0, src, a0, cda_ldw_exc);
			ldw(s_space, 4, src, a1, cda_ldw_exc);
			src -= 0 * sizeof(unsigned int);
			dst -= 2 * sizeof(unsigned int);
			len += 1;
			goto do2;
		case 0:
			if (len == 0)
				return 0;
			/* a3 = ((unsigned int *) src)[0];
			   a0 = ((unsigned int *) src)[1]; */
			ldw(s_space, 0, src, a3, cda_ldw_exc);
			ldw(s_space, 4, src, a0, cda_ldw_exc);
			src -=-1 * sizeof(unsigned int);
			dst -= 1 * sizeof(unsigned int);
			len += 0;
			goto do3;
		case 1:
			/* a2 = ((unsigned int *) src)[0];
			   a3 = ((unsigned int *) src)[1]; */
			ldw(s_space, 0, src, a2, cda_ldw_exc);
			ldw(s_space, 4, src, a3, cda_ldw_exc);
			src -=-2 * sizeof(unsigned int);
			dst -= 0 * sizeof(unsigned int);
			len -= 1;
			if (len == 0)
				goto do0;
			goto do4;			/* No-op.  */
	}

	do
	{
		/* prefetch_src((const void *)(src + 4 * sizeof(unsigned int))); */
do4:
		/* a0 = ((unsigned int *) src)[0]; */
		ldw(s_space, 0, src, a0, cda_ldw_exc);
		/* ((unsigned int *) dst)[0] = MERGE (a2, sh_1, a3, sh_2); */
		stw(d_space, MERGE (a2, sh_1, a3, sh_2), 0, dst, cda_stw_exc);
do3:
		/* a1 = ((unsigned int *) src)[1]; */
		ldw(s_space, 4, src, a1, cda_ldw_exc);
		/* ((unsigned int *) dst)[1] = MERGE (a3, sh_1, a0, sh_2); */
		stw(d_space, MERGE (a3, sh_1, a0, sh_2), 4, dst, cda_stw_exc);
do2:
		/* a2 = ((unsigned int *) src)[2]; */
		ldw(s_space, 8, src, a2, cda_ldw_exc);
		/* ((unsigned int *) dst)[2] = MERGE (a0, sh_1, a1, sh_2); */
		stw(d_space, MERGE (a0, sh_1, a1, sh_2), 8, dst, cda_stw_exc);
do1:
		/* a3 = ((unsigned int *) src)[3]; */
		ldw(s_space, 12, src, a3, cda_ldw_exc);
		/* ((unsigned int *) dst)[3] = MERGE (a1, sh_1, a2, sh_2); */
		stw(d_space, MERGE (a1, sh_1, a2, sh_2), 12, dst, cda_stw_exc);

		src += 4 * sizeof(unsigned int);
		dst += 4 * sizeof(unsigned int);
		len -= 4;
	}
	while (len != 0);

do0:
	/* ((unsigned int *) dst)[0] = MERGE (a2, sh_1, a3, sh_2); */
	stw(d_space, MERGE (a2, sh_1, a3, sh_2), 0, dst, cda_stw_exc);

	preserve_branch(handle_load_error);
	preserve_branch(handle_store_error);

	return 0;

handle_load_error:
	__asm__ __volatile__ ("cda_ldw_exc:\n");
	d = &__get_cpu_var(exception_data);
	DPRINTF("cda_ldw_exc: o_len=%lu fault_addr=%lu o_src=%lu ret=%lu\n",
		o_len, d->fault_addr, o_src, o_len - d->fault_addr + o_src);
	return o_len * 4 - d->fault_addr + o_src;

handle_store_error:
	__asm__ __volatile__ ("cda_stw_exc:\n");
	d = &__get_cpu_var(exception_data);
	DPRINTF("cda_stw_exc: o_len=%lu fault_addr=%lu o_dst=%lu ret=%lu\n",
		o_len, d->fault_addr, o_dst, o_len - d->fault_addr + o_dst);
	return o_len * 4 - d->fault_addr + o_dst;
}


/* Returns 0 for success, otherwise, returns number of bytes not transferred. */
static unsigned long pa_memcpy(void *dstp, const void *srcp, unsigned long len)
{
	register unsigned long src, dst, t1, t2, t3;
	register unsigned char *pcs, *pcd;
	register unsigned int *pws, *pwd;
	register double *pds, *pdd;
	unsigned long ret = 0;
	unsigned long o_dst, o_src, o_len;
	struct exception_data *d;

	src = (unsigned long)srcp;
	dst = (unsigned long)dstp;
	pcs = (unsigned char *)srcp;
	pcd = (unsigned char *)dstp;

	o_dst = dst; o_src = src; o_len = len;

	/* prefetch_src((const void *)srcp); */

	if (len < THRESHOLD)
		goto byte_copy;

	/* Check alignment */
	t1 = (src ^ dst);
	if (unlikely(t1 & (sizeof(double)-1)))
		goto unaligned_copy;

	/* src and dst have same alignment. */

	/* Copy bytes till we are double-aligned. */
	t2 = src & (sizeof(double) - 1);
	if (unlikely(t2 != 0)) {
		t2 = sizeof(double) - t2;
		while (t2 && len) {
			/* *pcd++ = *pcs++; */
			ldbma(s_space, pcs, t3, pmc_load_exc);
			len--;
			stbma(d_space, t3, pcd, pmc_store_exc);
			t2--;
		}
	}

	pds = (double *)pcs;
	pdd = (double *)pcd;

#if 0
	/* Copy 8 doubles at a time */
	while (len >= 8*sizeof(double)) {
		register double r1, r2, r3, r4, r5, r6, r7, r8;
		/* prefetch_src((char *)pds + L1_CACHE_BYTES); */
		flddma(s_space, pds, r1, pmc_load_exc);
		flddma(s_space, pds, r2, pmc_load_exc);
		flddma(s_space, pds, r3, pmc_load_exc);
		flddma(s_space, pds, r4, pmc_load_exc);
		fstdma(d_space, r1, pdd, pmc_store_exc);
		fstdma(d_space, r2, pdd, pmc_store_exc);
		fstdma(d_space, r3, pdd, pmc_store_exc);
		fstdma(d_space, r4, pdd, pmc_store_exc);

#if 0
		if (L1_CACHE_BYTES <= 32)
			prefetch_src((char *)pds + L1_CACHE_BYTES);
#endif
		flddma(s_space, pds, r5, pmc_load_exc);
		flddma(s_space, pds, r6, pmc_load_exc);
		flddma(s_space, pds, r7, pmc_load_exc);
		flddma(s_space, pds, r8, pmc_load_exc);
		fstdma(d_space, r5, pdd, pmc_store_exc);
		fstdma(d_space, r6, pdd, pmc_store_exc);
		fstdma(d_space, r7, pdd, pmc_store_exc);
		fstdma(d_space, r8, pdd, pmc_store_exc);
		len -= 8*sizeof(double);
	}
#endif

	pws = (unsigned int *)pds;
	pwd = (unsigned int *)pdd;

word_copy:
	while (len >= 8*sizeof(unsigned int)) {
		register unsigned int r1,r2,r3,r4,r5,r6,r7,r8;
		/* prefetch_src((char *)pws + L1_CACHE_BYTES); */
		ldwma(s_space, pws, r1, pmc_load_exc);
		ldwma(s_space, pws, r2, pmc_load_exc);
		ldwma(s_space, pws, r3, pmc_load_exc);
		ldwma(s_space, pws, r4, pmc_load_exc);
		stwma(d_space, r1, pwd, pmc_store_exc);
		stwma(d_space, r2, pwd, pmc_store_exc);
		stwma(d_space, r3, pwd, pmc_store_exc);
		stwma(d_space, r4, pwd, pmc_store_exc);

		ldwma(s_space, pws, r5, pmc_load_exc);
		ldwma(s_space, pws, r6, pmc_load_exc);
		ldwma(s_space, pws, r7, pmc_load_exc);
		ldwma(s_space, pws, r8, pmc_load_exc);
		stwma(d_space, r5, pwd, pmc_store_exc);
		stwma(d_space, r6, pwd, pmc_store_exc);
		stwma(d_space, r7, pwd, pmc_store_exc);
		stwma(d_space, r8, pwd, pmc_store_exc);
		len -= 8*sizeof(unsigned int);
	}

	while (len >= 4*sizeof(unsigned int)) {
		register unsigned int r1,r2,r3,r4;
		ldwma(s_space, pws, r1, pmc_load_exc);
		ldwma(s_space, pws, r2, pmc_load_exc);
		ldwma(s_space, pws, r3, pmc_load_exc);
		ldwma(s_space, pws, r4, pmc_load_exc);
		stwma(d_space, r1, pwd, pmc_store_exc);
		stwma(d_space, r2, pwd, pmc_store_exc);
		stwma(d_space, r3, pwd, pmc_store_exc);
		stwma(d_space, r4, pwd, pmc_store_exc);
		len -= 4*sizeof(unsigned int);
	}

	pcs = (unsigned char *)pws;
	pcd = (unsigned char *)pwd;

byte_copy:
	while (len) {
		/* *pcd++ = *pcs++; */
		ldbma(s_space, pcs, t3, pmc_load_exc);
		stbma(d_space, t3, pcd, pmc_store_exc);
		len--;
	}

	return 0;

unaligned_copy:
	/* possibly we are aligned on a word, but not on a double... */
	if (likely((t1 & (sizeof(unsigned int)-1)) == 0)) {
		t2 = src & (sizeof(unsigned int) - 1);

		if (unlikely(t2 != 0)) {
			t2 = sizeof(unsigned int) - t2;
			while (t2) {
				/* *pcd++ = *pcs++; */
				ldbma(s_space, pcs, t3, pmc_load_exc);
				stbma(d_space, t3, pcd, pmc_store_exc);
				len--;
				t2--;
			}
		}

		pws = (unsigned int *)pcs;
		pwd = (unsigned int *)pcd;
		goto word_copy;
	}

	/* Align the destination.  */
	if (unlikely((dst & (sizeof(unsigned int) - 1)) != 0)) {
		t2 = sizeof(unsigned int) - (dst & (sizeof(unsigned int) - 1));
		while (t2) {
			/* *pcd++ = *pcs++; */
			ldbma(s_space, pcs, t3, pmc_load_exc);
			stbma(d_space, t3, pcd, pmc_store_exc);
			len--;
			t2--;
		}
		dst = (unsigned long)pcd;
		src = (unsigned long)pcs;
	}

	ret = copy_dstaligned(dst, src, len / sizeof(unsigned int), 
		o_dst, o_src, o_len);
	if (ret)
		return ret;

	pcs += (len & -sizeof(unsigned int));
	pcd += (len & -sizeof(unsigned int));
	len %= sizeof(unsigned int);

	preserve_branch(handle_load_error);
	preserve_branch(handle_store_error);

	goto byte_copy;

handle_load_error:
	__asm__ __volatile__ ("pmc_load_exc:\n");
	d = &__get_cpu_var(exception_data);
	DPRINTF("pmc_load_exc: o_len=%lu fault_addr=%lu o_src=%lu ret=%lu\n",
		o_len, d->fault_addr, o_src, o_len - d->fault_addr + o_src);
	return o_len - d->fault_addr + o_src;

handle_store_error:
	__asm__ __volatile__ ("pmc_store_exc:\n");
	d = &__get_cpu_var(exception_data);
	DPRINTF("pmc_store_exc: o_len=%lu fault_addr=%lu o_dst=%lu ret=%lu\n",
		o_len, d->fault_addr, o_dst, o_len - d->fault_addr + o_dst);
	return o_len - d->fault_addr + o_dst;
}

#ifdef __KERNEL__
unsigned long copy_to_user(void __user *dst, const void *src, unsigned long len)
{
	mtsp(get_kernel_space(), 1);
	mtsp(get_user_space(), 2);
	return pa_memcpy((void __force *)dst, src, len);
}

EXPORT_SYMBOL(__copy_from_user);
unsigned long __copy_from_user(void *dst, const void __user *src, unsigned long len)
{
	mtsp(get_user_space(), 1);
	mtsp(get_kernel_space(), 2);
	return pa_memcpy(dst, (void __force *)src, len);
}

unsigned long copy_in_user(void __user *dst, const void __user *src, unsigned long len)
{
	mtsp(get_user_space(), 1);
	mtsp(get_user_space(), 2);
	return pa_memcpy((void __force *)dst, (void __force *)src, len);
}


void * memcpy(void * dst,const void *src, size_t count)
{
	mtsp(get_kernel_space(), 1);
	mtsp(get_kernel_space(), 2);
	pa_memcpy(dst, src, count);
	return dst;
}

EXPORT_SYMBOL(copy_to_user);
EXPORT_SYMBOL(copy_from_user);
EXPORT_SYMBOL(copy_in_user);
EXPORT_SYMBOL(memcpy);
#endif
Commit	Line	Data
1da177e4 LT	1	/*
	2	* Optimized memory copy routines.
	3	*
	4	* Copyright (C) 2004 Randolph Chung <tausq@debian.org>
	5	*
	6	* This program is free software; you can redistribute it and/or modify
	7	* it under the terms of the GNU General Public License as published by
	8	* the Free Software Foundation; either version 2, or (at your option)
	9	* any later version.
	10	*
	11	* This program is distributed in the hope that it will be useful,
	12	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	13	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	14	* GNU General Public License for more details.
	15	*
	16	* You should have received a copy of the GNU General Public License
	17	* along with this program; if not, write to the Free Software
	18	* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
	19	*
	20	* Portions derived from the GNU C Library
	21	* Copyright (C) 1991, 1997, 2003 Free Software Foundation, Inc.
	22	*
	23	* Several strategies are tried to try to get the best performance for various
	24	* conditions. In the optimal case, we copy 64-bytes in an unrolled loop using
	25	* fp regs. This is followed by loops that copy 32- or 16-bytes at a time using
	26	* general registers. Unaligned copies are handled either by aligning the
	27	* destination and then using shift-and-write method, or in a few cases by
	28	* falling back to a byte-at-a-time copy.
	29	*
	30	* I chose to implement this in C because it is easier to maintain and debug,
	31	* and in my experiments it appears that the C code generated by gcc (3.3/3.4
	32	* at the time of writing) is fairly optimal. Unfortunately some of the
	33	* semantics of the copy routine (exception handling) is difficult to express
	34	* in C, so we have to play some tricks to get it to work.
	35	*
	36	* All the loads and stores are done via explicit asm() code in order to use
	37	* the right space registers.
	38	*
	39	* Testing with various alignments and buffer sizes shows that this code is
	40	* often >10x faster than a simple byte-at-a-time copy, even for strangely
	41	* aligned operands. It is interesting to note that the glibc version
	42	* of memcpy (written in C) is actually quite fast already. This routine is
	43	* able to beat it by 30-40% for aligned copies because of the loop unrolling,
	44	* but in some cases the glibc version is still slightly faster. This lends
	45	* more credibility that gcc can generate very good code as long as we are
	46	* careful.
	47	*
	48	* TODO:
	49	* - cache prefetching needs more experimentation to get optimal settings
	50	* - try not to use the post-increment address modifiers; they create additional
	51	* interlocks
	52	* - replace byte-copy loops with stybs sequences
	53	*/
	54
	55	#ifdef __KERNEL__
1da177e4 LT	56	#include <linux/module.h>
	57	#include <linux/compiler.h>
	58	#include <asm/uaccess.h>
	59	#define s_space "%%sr1"
	60	#define d_space "%%sr2"
	61	#else
	62	#include "memcpy.h"
	63	#define s_space "%%sr0"
	64	#define d_space "%%sr0"
	65	#define pa_memcpy new2_copy
	66	#endif
	67
	68	DECLARE_PER_CPU(struct exception_data, exception_data);
	69
	70	#define preserve_branch(label) do { \
	71	volatile int dummy; \
	72	/* The following branch is never taken, it's just here to */ \
	73	/* prevent gcc from optimizing away our exception code. */ \
	74	if (unlikely(dummy != dummy)) \
	75	goto label; \
	76	} while (0)
	77
	78	#define get_user_space() (segment_eq(get_fs(), KERNEL_DS) ? 0 : mfsp(3))
	79	#define get_kernel_space() (0)
	80
	81	#define MERGE(w0, sh_1, w1, sh_2) ({ \
	82	unsigned int _r; \
	83	asm volatile ( \
	84	"mtsar %3\n" \
	85	"shrpw %1, %2, %%sar, %0\n" \
	86	: "=r"(_r) \
	87	: "r"(w0), "r"(w1), "r"(sh_2) \
	88	); \
	89	_r; \
	90	})
	91	#define THRESHOLD 16
	92
	93	#ifdef DEBUG_MEMCPY
91bae23c	94	#define DPRINTF(fmt, args...) do { printk(KERN_DEBUG "%s:%d:%s ", __FILE__, __LINE__, __func__ ); printk(KERN_DEBUG fmt, ##args ); } while (0)
1da177e4 LT	95	#else
	96	#define DPRINTF(fmt, args...)
	97	#endif
	98
1da177e4 LT	99	#define def_load_ai_insn(_insn,_sz,_tt,_s,_a,_t,_e) \
1da177e4 LT	100	__asm__ __volatile__ ( \
0b3d643f HD	101	"1:\t" #_insn ",ma " #_sz "(" _s ",%1), %0\n\t" \
0b3d643f HD	102	ASM_EXCEPTIONTABLE_ENTRY(1b,_e) \
1da177e4 LT	103	: _tt(_t), "+r"(_a) \
	104	: \
	105	: "r8")
	106
	107	#define def_store_ai_insn(_insn,_sz,_tt,_s,_a,_t,_e) \
	108	__asm__ __volatile__ ( \
0b3d643f HD	109	"1:\t" #_insn ",ma %1, " #_sz "(" _s ",%0)\n\t" \
0b3d643f HD	110	ASM_EXCEPTIONTABLE_ENTRY(1b,_e) \
1da177e4 LT	111	: "+r"(_a) \
	112	: _tt(_t) \
	113	: "r8")
	114
	115	#define ldbma(_s, _a, _t, _e) def_load_ai_insn(ldbs,1,"=r",_s,_a,_t,_e)
	116	#define stbma(_s, _t, _a, _e) def_store_ai_insn(stbs,1,"r",_s,_a,_t,_e)
	117	#define ldwma(_s, _a, _t, _e) def_load_ai_insn(ldw,4,"=r",_s,_a,_t,_e)
	118	#define stwma(_s, _t, _a, _e) def_store_ai_insn(stw,4,"r",_s,_a,_t,_e)
	119	#define flddma(_s, _a, _t, _e) def_load_ai_insn(fldd,8,"=f",_s,_a,_t,_e)
	120	#define fstdma(_s, _t, _a, _e) def_store_ai_insn(fstd,8,"f",_s,_a,_t,_e)
	121
	122	#define def_load_insn(_insn,_tt,_s,_o,_a,_t,_e) \
	123	__asm__ __volatile__ ( \
0b3d643f HD	124	"1:\t" #_insn " " #_o "(" _s ",%1), %0\n\t" \
0b3d643f HD	125	ASM_EXCEPTIONTABLE_ENTRY(1b,_e) \
1da177e4 LT	126	: _tt(_t) \
	127	: "r"(_a) \
	128	: "r8")
	129
	130	#define def_store_insn(_insn,_tt,_s,_t,_o,_a,_e) \
	131	__asm__ __volatile__ ( \
0b3d643f HD	132	"1:\t" #_insn " %0, " #_o "(" _s ",%1)\n\t" \
0b3d643f HD	133	ASM_EXCEPTIONTABLE_ENTRY(1b,_e) \
1da177e4 LT	134	: \
	135	: _tt(_t), "r"(_a) \
	136	: "r8")
	137
	138	#define ldw(_s,_o,_a,_t,_e) def_load_insn(ldw,"=r",_s,_o,_a,_t,_e)
	139	#define stw(_s,_t,_o,_a,_e) def_store_insn(stw,"r",_s,_t,_o,_a,_e)
	140
	141	#ifdef CONFIG_PREFETCH
f13cec84	142	static inline void prefetch_src(const void *addr)
1da177e4 LT	143	{
	144	__asm__("ldw 0(" s_space ",%0), %%r0" : : "r" (addr));
	145	}
	146
f13cec84	147	static inline void prefetch_dst(const void *addr)
1da177e4 LT	148	{
	149	__asm__("ldd 0(" d_space ",%0), %%r0" : : "r" (addr));
	150	}
	151	#else
0b3d643f HD	152	#define prefetch_src(addr) do { } while(0)
0b3d643f HD	153	#define prefetch_dst(addr) do { } while(0)
1da177e4 LT	154	#endif
	155
	156	/* Copy from a not-aligned src to an aligned dst, using shifts. Handles 4 words
	157	* per loop. This code is derived from glibc.
	158	*/
	159	static inline unsigned long copy_dstaligned(unsigned long dst, unsigned long src, unsigned long len, unsigned long o_dst, unsigned long o_src, unsigned long o_len)
	160	{
	161	/* gcc complains that a2 and a3 may be uninitialized, but actually
	162	* they cannot be. Initialize a2/a3 to shut gcc up.
	163	*/
	164	register unsigned int a0, a1, a2 = 0, a3 = 0;
	165	int sh_1, sh_2;
	166	struct exception_data *d;
	167
	168	/* prefetch_src((const void )src); /
	169
	170	/* Calculate how to shift a word read at the memory operation
	171	aligned srcp to make it aligned for copy. */
	172	sh_1 = 8 * (src % sizeof(unsigned int));
	173	sh_2 = 8 * sizeof(unsigned int) - sh_1;
	174
	175	/* Make src aligned by rounding it down. */
	176	src &= -sizeof(unsigned int);
	177
	178	switch (len % 4)
	179	{
	180	case 2:
	181	/* a1 = ((unsigned int *) src)[0];
	182	a2 = ((unsigned int ) src)[1]; /
	183	ldw(s_space, 0, src, a1, cda_ldw_exc);
	184	ldw(s_space, 4, src, a2, cda_ldw_exc);
	185	src -= 1 * sizeof(unsigned int);
	186	dst -= 3 * sizeof(unsigned int);
	187	len += 2;
	188	goto do1;
	189	case 3:
	190	/* a0 = ((unsigned int *) src)[0];
	191	a1 = ((unsigned int ) src)[1]; /
	192	ldw(s_space, 0, src, a0, cda_ldw_exc);
	193	ldw(s_space, 4, src, a1, cda_ldw_exc);
	194	src -= 0 * sizeof(unsigned int);
	195	dst -= 2 * sizeof(unsigned int);
	196	len += 1;
	197	goto do2;
	198	case 0:
	199	if (len == 0)
	200	return 0;
	201	/* a3 = ((unsigned int *) src)[0];
	202	a0 = ((unsigned int ) src)[1]; /
	203	ldw(s_space, 0, src, a3, cda_ldw_exc);
	204	ldw(s_space, 4, src, a0, cda_ldw_exc);
	205	src -=-1 * sizeof(unsigned int);
	206	dst -= 1 * sizeof(unsigned int);
	207	len += 0;
	208	goto do3;
	209	case 1:
	210	/* a2 = ((unsigned int *) src)[0];
	211	a3 = ((unsigned int ) src)[1]; /
	212	ldw(s_space, 0, src, a2, cda_ldw_exc);
	213	ldw(s_space, 4, src, a3, cda_ldw_exc);
	214	src -=-2 * sizeof(unsigned int);
	215	dst -= 0 * sizeof(unsigned int);
	216	len -= 1;
	217	if (len == 0)
218	goto do0;
219	goto do4; /* No-op. */
220	}
221
222	do
223	{
224	/* prefetch_src((const void )(src + 4 sizeof(unsigned int))); */
225	do4:
226	/* a0 = ((unsigned int ) src)[0]; /
227	ldw(s_space, 0, src, a0, cda_ldw_exc);
228	/* ((unsigned int ) dst)[0] = MERGE (a2, sh_1, a3, sh_2); /
229	stw(d_space, MERGE (a2, sh_1, a3, sh_2), 0, dst, cda_stw_exc);
230	do3:
231	/* a1 = ((unsigned int ) src)[1]; /
232	ldw(s_space, 4, src, a1, cda_ldw_exc);
233	/* ((unsigned int ) dst)[1] = MERGE (a3, sh_1, a0, sh_2); /
234	stw(d_space, MERGE (a3, sh_1, a0, sh_2), 4, dst, cda_stw_exc);
235	do2:
236	/* a2 = ((unsigned int ) src)[2]; /
237	ldw(s_space, 8, src, a2, cda_ldw_exc);
238	/* ((unsigned int ) dst)[2] = MERGE (a0, sh_1, a1, sh_2); /
239	stw(d_space, MERGE (a0, sh_1, a1, sh_2), 8, dst, cda_stw_exc);
240	do1:
241	/* a3 = ((unsigned int ) src)[3]; /
242	ldw(s_space, 12, src, a3, cda_ldw_exc);
243	/* ((unsigned int ) dst)[3] = MERGE (a1, sh_1, a2, sh_2); /
244	stw(d_space, MERGE (a1, sh_1, a2, sh_2), 12, dst, cda_stw_exc);
245
246	src += 4 * sizeof(unsigned int);
247	dst += 4 * sizeof(unsigned int);
248	len -= 4;
249	}
250	while (len != 0);
251
252	do0:
253	/* ((unsigned int ) dst)[0] = MERGE (a2, sh_1, a3, sh_2); /
254	stw(d_space, MERGE (a2, sh_1, a3, sh_2), 0, dst, cda_stw_exc);
255
256	preserve_branch(handle_load_error);
257	preserve_branch(handle_store_error);
258
259	return 0;
260
261	handle_load_error:
262	__asm__ __volatile__ ("cda_ldw_exc:\n");
263	d = &__get_cpu_var(exception_data);
264	DPRINTF("cda_ldw_exc: o_len=%lu fault_addr=%lu o_src=%lu ret=%lu\n",
265	o_len, d->fault_addr, o_src, o_len - d->fault_addr + o_src);
266	return o_len * 4 - d->fault_addr + o_src;
267
268	handle_store_error:
269	__asm__ __volatile__ ("cda_stw_exc:\n");
270	d = &__get_cpu_var(exception_data);
271	DPRINTF("cda_stw_exc: o_len=%lu fault_addr=%lu o_dst=%lu ret=%lu\n",
272	o_len, d->fault_addr, o_dst, o_len - d->fault_addr + o_dst);
273	return o_len * 4 - d->fault_addr + o_dst;
274	}
275
276
277	/* Returns 0 for success, otherwise, returns number of bytes not transferred. */
8f47cb87	278	static unsigned long pa_memcpy(void dstp, const void srcp, unsigned long len)
1da177e4 LT	279	{
	280	register unsigned long src, dst, t1, t2, t3;
	281	register unsigned char pcs, pcd;
	282	register unsigned int pws, pwd;
	283	register double pds, pdd;
	284	unsigned long ret = 0;
	285	unsigned long o_dst, o_src, o_len;
	286	struct exception_data *d;
	287
	288	src = (unsigned long)srcp;
	289	dst = (unsigned long)dstp;
	290	pcs = (unsigned char *)srcp;
	291	pcd = (unsigned char *)dstp;
	292
	293	o_dst = dst; o_src = src; o_len = len;
	294
	295	/* prefetch_src((const void )srcp); /
	296
	297	if (len < THRESHOLD)
	298	goto byte_copy;
	299
	300	/* Check alignment */
	301	t1 = (src ^ dst);
	302	if (unlikely(t1 & (sizeof(double)-1)))
	303	goto unaligned_copy;
	304
	305	/* src and dst have same alignment. */
	306
	307	/* Copy bytes till we are double-aligned. */
	308	t2 = src & (sizeof(double) - 1);
	309	if (unlikely(t2 != 0)) {
	310	t2 = sizeof(double) - t2;
	311	while (t2 && len) {
	312	/* pcd++ = pcs++; */
	313	ldbma(s_space, pcs, t3, pmc_load_exc);
	314	len--;
	315	stbma(d_space, t3, pcd, pmc_store_exc);
	316	t2--;
	317	}
	318	}
	319
	320	pds = (double *)pcs;
	321	pdd = (double *)pcd;
	322
fa681a18	323	#if 0
1da177e4 LT	324	/* Copy 8 doubles at a time */
	325	while (len >= 8*sizeof(double)) {
	326	register double r1, r2, r3, r4, r5, r6, r7, r8;
	327	/* prefetch_src((char )pds + L1_CACHE_BYTES); /
	328	flddma(s_space, pds, r1, pmc_load_exc);
	329	flddma(s_space, pds, r2, pmc_load_exc);
	330	flddma(s_space, pds, r3, pmc_load_exc);
	331	flddma(s_space, pds, r4, pmc_load_exc);
	332	fstdma(d_space, r1, pdd, pmc_store_exc);
	333	fstdma(d_space, r2, pdd, pmc_store_exc);
	334	fstdma(d_space, r3, pdd, pmc_store_exc);
	335	fstdma(d_space, r4, pdd, pmc_store_exc);
	336
	337	#if 0
	338	if (L1_CACHE_BYTES <= 32)
	339	prefetch_src((char *)pds + L1_CACHE_BYTES);
	340	#endif
	341	flddma(s_space, pds, r5, pmc_load_exc);
	342	flddma(s_space, pds, r6, pmc_load_exc);
	343	flddma(s_space, pds, r7, pmc_load_exc);
	344	flddma(s_space, pds, r8, pmc_load_exc);
	345	fstdma(d_space, r5, pdd, pmc_store_exc);
	346	fstdma(d_space, r6, pdd, pmc_store_exc);
	347	fstdma(d_space, r7, pdd, pmc_store_exc);
	348	fstdma(d_space, r8, pdd, pmc_store_exc);
	349	len -= 8*sizeof(double);
	350	}
fa681a18	351	#endif
1da177e4 LT	352
	353	pws = (unsigned int *)pds;
	354	pwd = (unsigned int *)pdd;
	355
	356	word_copy:
	357	while (len >= 8*sizeof(unsigned int)) {
	358	register unsigned int r1,r2,r3,r4,r5,r6,r7,r8;
	359	/* prefetch_src((char )pws + L1_CACHE_BYTES); /
	360	ldwma(s_space, pws, r1, pmc_load_exc);
	361	ldwma(s_space, pws, r2, pmc_load_exc);
	362	ldwma(s_space, pws, r3, pmc_load_exc);
	363	ldwma(s_space, pws, r4, pmc_load_exc);
	364	stwma(d_space, r1, pwd, pmc_store_exc);
	365	stwma(d_space, r2, pwd, pmc_store_exc);
	366	stwma(d_space, r3, pwd, pmc_store_exc);
	367	stwma(d_space, r4, pwd, pmc_store_exc);
	368
	369	ldwma(s_space, pws, r5, pmc_load_exc);
	370	ldwma(s_space, pws, r6, pmc_load_exc);
	371	ldwma(s_space, pws, r7, pmc_load_exc);
	372	ldwma(s_space, pws, r8, pmc_load_exc);
	373	stwma(d_space, r5, pwd, pmc_store_exc);
	374	stwma(d_space, r6, pwd, pmc_store_exc);
	375	stwma(d_space, r7, pwd, pmc_store_exc);
	376	stwma(d_space, r8, pwd, pmc_store_exc);
	377	len -= 8*sizeof(unsigned int);
	378	}
	379
	380	while (len >= 4*sizeof(unsigned int)) {
	381	register unsigned int r1,r2,r3,r4;
	382	ldwma(s_space, pws, r1, pmc_load_exc);
	383	ldwma(s_space, pws, r2, pmc_load_exc);
	384	ldwma(s_space, pws, r3, pmc_load_exc);
	385	ldwma(s_space, pws, r4, pmc_load_exc);
	386	stwma(d_space, r1, pwd, pmc_store_exc);
	387	stwma(d_space, r2, pwd, pmc_store_exc);
	388	stwma(d_space, r3, pwd, pmc_store_exc);
	389	stwma(d_space, r4, pwd, pmc_store_exc);
	390	len -= 4*sizeof(unsigned int);
	391	}
	392
	393	pcs = (unsigned char *)pws;
	394	pcd = (unsigned char *)pwd;
	395
	396	byte_copy:
	397	while (len) {
	398	/* pcd++ = pcs++; */
	399	ldbma(s_space, pcs, t3, pmc_load_exc);
	400	stbma(d_space, t3, pcd, pmc_store_exc);
	401	len--;
	402	}
	403
	404	return 0;
	405
	406	unaligned_copy:
	407	/* possibly we are aligned on a word, but not on a double... */
87451d85	408	if (likely((t1 & (sizeof(unsigned int)-1)) == 0)) {
1da177e4 LT	409	t2 = src & (sizeof(unsigned int) - 1);
	410
	411	if (unlikely(t2 != 0)) {
	412	t2 = sizeof(unsigned int) - t2;
	413	while (t2) {
	414	/* pcd++ = pcs++; */
	415	ldbma(s_space, pcs, t3, pmc_load_exc);
	416	stbma(d_space, t3, pcd, pmc_store_exc);
	417	len--;
	418	t2--;
	419	}
	420	}
	421
	422	pws = (unsigned int *)pcs;
	423	pwd = (unsigned int *)pcd;
	424	goto word_copy;
	425	}
	426
	427	/* Align the destination. */
	428	if (unlikely((dst & (sizeof(unsigned int) - 1)) != 0)) {
	429	t2 = sizeof(unsigned int) - (dst & (sizeof(unsigned int) - 1));
	430	while (t2) {
	431	/* pcd++ = pcs++; */
	432	ldbma(s_space, pcs, t3, pmc_load_exc);
	433	stbma(d_space, t3, pcd, pmc_store_exc);
	434	len--;
	435	t2--;
	436	}
	437	dst = (unsigned long)pcd;
	438	src = (unsigned long)pcs;
	439	}
	440
	441	ret = copy_dstaligned(dst, src, len / sizeof(unsigned int),
	442	o_dst, o_src, o_len);
	443	if (ret)
	444	return ret;
	445
	446	pcs += (len & -sizeof(unsigned int));
	447	pcd += (len & -sizeof(unsigned int));
	448	len %= sizeof(unsigned int);
	449
	450	preserve_branch(handle_load_error);
	451	preserve_branch(handle_store_error);
	452
	453	goto byte_copy;
	454
	455	handle_load_error:
	456	__asm__ __volatile__ ("pmc_load_exc:\n");
	457	d = &__get_cpu_var(exception_data);
	458	DPRINTF("pmc_load_exc: o_len=%lu fault_addr=%lu o_src=%lu ret=%lu\n",
	459	o_len, d->fault_addr, o_src, o_len - d->fault_addr + o_src);
	460	return o_len - d->fault_addr + o_src;
	461
	462	handle_store_error:
	463	__asm__ __volatile__ ("pmc_store_exc:\n");
	464	d = &__get_cpu_var(exception_data);
	465	DPRINTF("pmc_store_exc: o_len=%lu fault_addr=%lu o_dst=%lu ret=%lu\n",
	466	o_len, d->fault_addr, o_dst, o_len - d->fault_addr + o_dst);
	467	return o_len - d->fault_addr + o_dst;
	468	}
	469
	470	#ifdef __KERNEL__
	471	unsigned long copy_to_user(void __user dst, const void src, unsigned long len)
	472	{
473	mtsp(get_kernel_space(), 1);
474	mtsp(get_user_space(), 2);
475	return pa_memcpy((void __force *)dst, src, len);
476	}
477
888c31fc HD	478	EXPORT_SYMBOL(__copy_from_user);
888c31fc HD	479	unsigned long __copy_from_user(void dst, const void __user src, unsigned long len)
1da177e4 LT	480	{
	481	mtsp(get_user_space(), 1);
	482	mtsp(get_kernel_space(), 2);
	483	return pa_memcpy(dst, (void __force *)src, len);
	484	}
	485
	486	unsigned long copy_in_user(void __user dst, const void __user src, unsigned long len)
	487	{
	488	mtsp(get_user_space(), 1);
	489	mtsp(get_user_space(), 2);
	490	return pa_memcpy((void __force )dst, (void __force )src, len);
	491	}
	492
	493
	494	void * memcpy(void * dst,const void *src, size_t count)
	495	{
	496	mtsp(get_kernel_space(), 1);
	497	mtsp(get_kernel_space(), 2);
	498	pa_memcpy(dst, src, count);
	499	return dst;
	500	}
	501
	502	EXPORT_SYMBOL(copy_to_user);
	503	EXPORT_SYMBOL(copy_from_user);
	504	EXPORT_SYMBOL(copy_in_user);
	505	EXPORT_SYMBOL(memcpy);
	506	#endif