/*
 * LZ4 HC - High Compression Mode of LZ4
 * Copyright (C) 2011-2012, Yann Collet.
 * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php)
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 *     * Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above
 * copyright notice, this list of conditions and the following disclaimer
 * in the documentation and/or other materials provided with the
 * distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * You can contact the author at :
 * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html
 * - LZ4 source repository : http://code.google.com/p/lz4/
 *
 *  Changed for kernel use by:
 *  Chanho Min <chanho.min@lge.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/lz4.h>
#include <asm/unaligned.h>
#include "lz4defs.h"

struct lz4hc_data {
	const u8 *base;
	HTYPE hashtable[HASHTABLESIZE];
	u16 chaintable[MAXD];
	const u8 *nexttoupdate;
} __attribute__((__packed__));

static inline int lz4hc_init(struct lz4hc_data *hc4, const u8 *base)
{
	memset((void *)hc4->hashtable, 0, sizeof(hc4->hashtable));
	memset(hc4->chaintable, 0xFF, sizeof(hc4->chaintable));

#if LZ4_ARCH64
	hc4->nexttoupdate = base + 1;
#else
	hc4->nexttoupdate = base;
#endif
	hc4->base = base;
	return 1;
}

/* Update chains up to ip (excluded) */
static inline void lz4hc_insert(struct lz4hc_data *hc4, const u8 *ip)
{
	u16 *chaintable = hc4->chaintable;
	HTYPE *hashtable  = hc4->hashtable;
#if LZ4_ARCH64
	const BYTE * const base = hc4->base;
#else
	const int base = 0;
#endif

	while (hc4->nexttoupdate < ip) {
		const u8 *p = hc4->nexttoupdate;
		size_t delta = p - (hashtable[HASH_VALUE(p)] + base);
		if (delta > MAX_DISTANCE)
			delta = MAX_DISTANCE;
		chaintable[(size_t)(p) & MAXD_MASK] = (u16)delta;
		hashtable[HASH_VALUE(p)] = (p) - base;
		hc4->nexttoupdate++;
	}
}

static inline size_t lz4hc_commonlength(const u8 *p1, const u8 *p2,
		const u8 *const matchlimit)
{
	const u8 *p1t = p1;

	while (p1t < matchlimit - (STEPSIZE - 1)) {
#if LZ4_ARCH64
		u64 diff = A64(p2) ^ A64(p1t);
#else
		u32 diff = A32(p2) ^ A32(p1t);
#endif
		if (!diff) {
			p1t += STEPSIZE;
			p2 += STEPSIZE;
			continue;
		}
		p1t += LZ4_NBCOMMONBYTES(diff);
		return p1t - p1;
	}
#if LZ4_ARCH64
	if ((p1t < (matchlimit-3)) && (A32(p2) == A32(p1t))) {
		p1t += 4;
		p2 += 4;
	}
#endif

	if ((p1t < (matchlimit - 1)) && (A16(p2) == A16(p1t))) {
		p1t += 2;
		p2 += 2;
	}
	if ((p1t < matchlimit) && (*p2 == *p1t))
		p1t++;
	return p1t - p1;
}

static inline int lz4hc_insertandfindbestmatch(struct lz4hc_data *hc4,
		const u8 *ip, const u8 *const matchlimit, const u8 **matchpos)
{
	u16 *const chaintable = hc4->chaintable;
	HTYPE *const hashtable = hc4->hashtable;
	const u8 *ref;
#if LZ4_ARCH64
	const BYTE * const base = hc4->base;
#else
	const int base = 0;
#endif
	int nbattempts = MAX_NB_ATTEMPTS;
	size_t repl = 0, ml = 0;
	u16 delta;

	/* HC4 match finder */
	lz4hc_insert(hc4, ip);
	ref = hashtable[HASH_VALUE(ip)] + base;

	/* potential repetition */
	if (ref >= ip-4) {
		/* confirmed */
		if (A32(ref) == A32(ip)) {
			delta = (u16)(ip-ref);
			repl = ml  = lz4hc_commonlength(ip + MINMATCH,
					ref + MINMATCH, matchlimit) + MINMATCH;
			*matchpos = ref;
		}
		ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK];
	}

	while ((ref >= ip - MAX_DISTANCE) && nbattempts) {
		nbattempts--;
		if (*(ref + ml) == *(ip + ml)) {
			if (A32(ref) == A32(ip)) {
				size_t mlt =
					lz4hc_commonlength(ip + MINMATCH,
					ref + MINMATCH, matchlimit) + MINMATCH;
				if (mlt > ml) {
					ml = mlt;
					*matchpos = ref;
				}
			}
		}
		ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK];
	}

	/* Complete table */
	if (repl) {
		const BYTE *ptr = ip;
		const BYTE *end;
		end = ip + repl - (MINMATCH-1);
		/* Pre-Load */
		while (ptr < end - delta) {
			chaintable[(size_t)(ptr) & MAXD_MASK] = delta;
			ptr++;
		}
		do {
			chaintable[(size_t)(ptr) & MAXD_MASK] = delta;
			/* Head of chain */
			hashtable[HASH_VALUE(ptr)] = (ptr) - base;
			ptr++;
		} while (ptr < end);
		hc4->nexttoupdate = end;
	}

	return (int)ml;
}

static inline int lz4hc_insertandgetwidermatch(struct lz4hc_data *hc4,
	const u8 *ip, const u8 *startlimit, const u8 *matchlimit, int longest,
	const u8 **matchpos, const u8 **startpos)
{
	u16 *const chaintable = hc4->chaintable;
	HTYPE *const hashtable = hc4->hashtable;
#if LZ4_ARCH64
	const BYTE * const base = hc4->base;
#else
	const int base = 0;
#endif
	const u8 *ref;
	int nbattempts = MAX_NB_ATTEMPTS;
	int delta = (int)(ip - startlimit);

	/* First Match */
	lz4hc_insert(hc4, ip);
	ref = hashtable[HASH_VALUE(ip)] + base;

	while ((ref >= ip - MAX_DISTANCE) && (ref >= hc4->base)
		&& (nbattempts)) {
		nbattempts--;
		if (*(startlimit + longest) == *(ref - delta + longest)) {
			if (A32(ref) == A32(ip)) {
				const u8 *reft = ref + MINMATCH;
				const u8 *ipt = ip + MINMATCH;
				const u8 *startt = ip;

				while (ipt < matchlimit-(STEPSIZE - 1)) {
					#if LZ4_ARCH64
					u64 diff = A64(reft) ^ A64(ipt);
					#else
					u32 diff = A32(reft) ^ A32(ipt);
					#endif

					if (!diff) {
						ipt += STEPSIZE;
						reft += STEPSIZE;
						continue;
					}
					ipt += LZ4_NBCOMMONBYTES(diff);
					goto _endcount;
				}
				#if LZ4_ARCH64
				if ((ipt < (matchlimit - 3))
					&& (A32(reft) == A32(ipt))) {
					ipt += 4;
					reft += 4;
				}
				ipt += 2;
				#endif
				if ((ipt < (matchlimit - 1))
					&& (A16(reft) == A16(ipt))) {
					reft += 2;
				}
				if ((ipt < matchlimit) && (*reft == *ipt))
					ipt++;
_endcount:
				reft = ref;

				while ((startt > startlimit)
					&& (reft > hc4->base)
					&& (startt[-1] == reft[-1])) {
					startt--;
					reft--;
				}

				if ((ipt - startt) > longest) {
					longest = (int)(ipt - startt);
					*matchpos = reft;
					*startpos = startt;
				}
			}
		}
		ref -= (size_t)chaintable[(size_t)(ref) & MAXD_MASK];
	}
	return longest;
}

static inline int lz4_encodesequence(const u8 **ip, u8 **op, const u8 **anchor,
		int ml, const u8 *ref)
{
	int length, len;
	u8 *token;

	/* Encode Literal length */
	length = (int)(*ip - *anchor);
	token = (*op)++;
	if (length >= (int)RUN_MASK) {
		*token = (RUN_MASK << ML_BITS);
		len = length - RUN_MASK;
		for (; len > 254 ; len -= 255)
			*(*op)++ = 255;
		*(*op)++ = (u8)len;
	} else
		*token = (length << ML_BITS);

	/* Copy Literals */
	LZ4_BLINDCOPY(*anchor, *op, length);

	/* Encode Offset */
	LZ4_WRITE_LITTLEENDIAN_16(*op, (u16)(*ip - ref));

	/* Encode MatchLength */
	len = (int)(ml - MINMATCH);
	if (len >= (int)ML_MASK) {
		*token += ML_MASK;
		len -= ML_MASK;
		for (; len > 509 ; len -= 510) {
			*(*op)++ = 255;
			*(*op)++ = 255;
		}
		if (len > 254) {
			len -= 255;
			*(*op)++ = 255;
		}
		*(*op)++ = (u8)len;
	} else
		*token += len;

	/* Prepare next loop */
	*ip += ml;
	*anchor = *ip;

	return 0;
}

static int lz4_compresshcctx(struct lz4hc_data *ctx,
		const char *source,
		char *dest,
		int isize)
{
	const u8 *ip = (const u8 *)source;
	const u8 *anchor = ip;
	const u8 *const iend = ip + isize;
	const u8 *const mflimit = iend - MFLIMIT;
	const u8 *const matchlimit = (iend - LASTLITERALS);

	u8 *op = (u8 *)dest;

	int ml, ml2, ml3, ml0;
	const u8 *ref = NULL;
	const u8 *start2 = NULL;
	const u8 *ref2 = NULL;
	const u8 *start3 = NULL;
	const u8 *ref3 = NULL;
	const u8 *start0;
	const u8 *ref0;
	int lastrun;

	ip++;

	/* Main Loop */
	while (ip < mflimit) {
		ml = lz4hc_insertandfindbestmatch(ctx, ip, matchlimit, (&ref));
		if (!ml) {
			ip++;
			continue;
		}

		/* saved, in case we would skip too much */
		start0 = ip;
		ref0 = ref;
		ml0 = ml;
_search2:
		if (ip+ml < mflimit)
			ml2 = lz4hc_insertandgetwidermatch(ctx, ip + ml - 2,
				ip + 1, matchlimit, ml, &ref2, &start2);
		else
			ml2 = ml;
		/* No better match */
		if (ml2 == ml) {
			lz4_encodesequence(&ip, &op, &anchor, ml, ref);
			continue;
		}

		if (start0 < ip) {
			/* empirical */
			if (start2 < ip + ml0) {
				ip = start0;
				ref = ref0;
				ml = ml0;
			}
		}
		/*
		 * Here, start0==ip
		 * First Match too small : removed
		 */
		if ((start2 - ip) < 3) {
			ml = ml2;
			ip = start2;
			ref = ref2;
			goto _search2;
		}

_search3:
		/*
		 * Currently we have :
		 * ml2 > ml1, and
		 * ip1+3 <= ip2 (usually < ip1+ml1)
		 */
		if ((start2 - ip) < OPTIMAL_ML) {
			int correction;
			int new_ml = ml;
			if (new_ml > OPTIMAL_ML)
				new_ml = OPTIMAL_ML;
			if (ip + new_ml > start2 + ml2 - MINMATCH)
				new_ml = (int)(start2 - ip) + ml2 - MINMATCH;
			correction = new_ml - (int)(start2 - ip);
			if (correction > 0) {
				start2 += correction;
				ref2 += correction;
				ml2 -= correction;
			}
		}
		/*
		 * Now, we have start2 = ip+new_ml,
		 * with new_ml=min(ml, OPTIMAL_ML=18)
		 */
		if (start2 + ml2 < mflimit)
			ml3 = lz4hc_insertandgetwidermatch(ctx,
				start2 + ml2 - 3, start2, matchlimit,
				ml2, &ref3, &start3);
		else
			ml3 = ml2;

		/* No better match : 2 sequences to encode */
		if (ml3 == ml2) {
			/* ip & ref are known; Now for ml */
			if (start2 < ip+ml)
				ml = (int)(start2 - ip);

			/* Now, encode 2 sequences */
			lz4_encodesequence(&ip, &op, &anchor, ml, ref);
			ip = start2;
			lz4_encodesequence(&ip, &op, &anchor, ml2, ref2);
			continue;
		}

		/* Not enough space for match 2 : remove it */
		if (start3 < ip + ml + 3) {
			/*
			 * can write Seq1 immediately ==> Seq2 is removed,
			 * so Seq3 becomes Seq1
			 */
			if (start3 >= (ip + ml)) {
				if (start2 < ip + ml) {
					int correction =
						(int)(ip + ml - start2);
					start2 += correction;
					ref2 += correction;
					ml2 -= correction;
					if (ml2 < MINMATCH) {
						start2 = start3;
						ref2 = ref3;
						ml2 = ml3;
					}
				}

				lz4_encodesequence(&ip, &op, &anchor, ml, ref);
				ip  = start3;
				ref = ref3;
				ml  = ml3;

				start0 = start2;
				ref0 = ref2;
				ml0 = ml2;
				goto _search2;
			}

			start2 = start3;
			ref2 = ref3;
			ml2 = ml3;
			goto _search3;
		}

		/*
		 * OK, now we have 3 ascending matches; let's write at least
		 * the first one ip & ref are known; Now for ml
		 */
		if (start2 < ip + ml) {
			if ((start2 - ip) < (int)ML_MASK) {
				int correction;
				if (ml > OPTIMAL_ML)
					ml = OPTIMAL_ML;
				if (ip + ml > start2 + ml2 - MINMATCH)
					ml = (int)(start2 - ip) + ml2
						- MINMATCH;
				correction = ml - (int)(start2 - ip);
				if (correction > 0) {
					start2 += correction;
					ref2 += correction;
					ml2 -= correction;
				}
			} else
				ml = (int)(start2 - ip);
		}
		lz4_encodesequence(&ip, &op, &anchor, ml, ref);

		ip = start2;
		ref = ref2;
		ml = ml2;

		start2 = start3;
		ref2 = ref3;
		ml2 = ml3;

		goto _search3;
	}

	/* Encode Last Literals */
	lastrun = (int)(iend - anchor);
	if (lastrun >= (int)RUN_MASK) {
		*op++ = (RUN_MASK << ML_BITS);
		lastrun -= RUN_MASK;
		for (; lastrun > 254 ; lastrun -= 255)
			*op++ = 255;
		*op++ = (u8) lastrun;
	} else
		*op++ = (lastrun << ML_BITS);
	memcpy(op, anchor, iend - anchor);
	op += iend - anchor;
	/* End */
	return (int) (((char *)op) - dest);
}

int lz4hc_compress(const unsigned char *src, size_t src_len,
			unsigned char *dst, size_t *dst_len, void *wrkmem)
{
	int ret = -1;
	int out_len = 0;

	struct lz4hc_data *hc4 = (struct lz4hc_data *)wrkmem;
	lz4hc_init(hc4, (const u8 *)src);
	out_len = lz4_compresshcctx((struct lz4hc_data *)hc4, (const u8 *)src,
		(char *)dst, (int)src_len);

	if (out_len < 0)
		goto exit;

	*dst_len = out_len;
	return 0;

exit:
	return ret;
}
EXPORT_SYMBOL(lz4hc_compress);

MODULE_LICENSE("Dual BSD/GPL");
MODULE_DESCRIPTION("LZ4HC compressor");
end of busy detection, special care must be taken to
make sure that both start and end interrupts are always cleared one after
the other.

1) Clearing of card busy bit is moved in mmc_cmd_irq() function where
unmasking of busy end bit is effectively handled.
2) Just before unmasking busy end event, busy start event is cleared by
writing card busy bit in MMCICLEAR register.
3) Finally, once we are no more busy with a command, busy end event is
cleared writing again card busy bit in MMCICLEAR register.

This patch has been tested with the ST Accordo5 machine, not yet supported
upstream but relies on the mmci driver.

Signed-off-by: Sarang Mairal &lt;sarang.mairal@garmin.com&gt;
Signed-off-by: Jean-Nicolas Graux &lt;jean-nicolas.graux@st.com&gt;
Reviewed-by: Linus Walleij &lt;linus.walleij@linaro.org&gt;
Tested-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
Signed-off-by: Ulf Hansson &lt;ulf.hansson@linaro.org&gt;
</div><div class='diffstat-header'><a href='/cgit.cgi/linux/net-next.git/diff/?id=5cad24d835772f9f709971a8d6fcf12afe53b2a7'>Diffstat</a> (limited to 'drivers/usb/image/microtek.c')</div><table summary='diffstat' class='diffstat'>