text: /*
   * U-boot - string.c Contains library routines.
   *
   * Copyright (c) 2005-2008 Analog Devices Inc.
   *
   * (C) Copyright 2000-2004
   * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   *
   * See file CREDITS for list of people who contributed to this
   * project.
   *
   * 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 of
   * the License, 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., 51 Franklin St, Fifth Floor, Boston,
   * MA 02110-1301 USA
   */
  
  #include <common.h>
  #include <config.h>
  #include <asm/blackfin.h>
  #include <asm/io.h>
  #include <asm/dma.h>
  
  char *strcpy(char *dest, const char *src)
  {
  	char *xdest = dest;
  	char temp = 0;
  
  	__asm__ __volatile__ (
  		"1:\t%2 = B [%1++] (Z);\n\t"
  		"B [%0++] = %2;\n\t"
  		"CC = %2;\n\t"
  		"if cc jump 1b (bp);\n"
  		: "=a"(dest), "=a"(src), "=d"(temp)
  		: "0"(dest), "1"(src), "2"(temp)
  		: "memory");
  
  	return xdest;
  }
  
  char *strncpy(char *dest, const char *src, size_t n)
  {
  	char *xdest = dest;
  	char temp = 0;
  
  	if (n == 0)
  		return xdest;
  
  	__asm__ __volatile__ (
  		"1:\t%3 = B [%1++] (Z);\n\t"
  		"B [%0++] = %3;\n\t"
  		"CC = %3;\n\t"
  		"if ! cc jump 2f;\n\t"
  		"%2 += -1;\n\t"
  		"CC = %2 == 0;\n\t"
  		"if ! cc jump 1b (bp);\n"
  		"2:\n"
  		: "=a"(dest), "=a"(src), "=da"(n), "=d"(temp)
  		: "0"(dest), "1"(src), "2"(n), "3"(temp)
  		: "memory");
  
  	return xdest;
  }
  
  int strcmp(const char *cs, const char *ct)
  {
  	char __res1, __res2;
  
  	__asm__ (
  		"1:\t%2 = B[%0++] (Z);\n\t"	/* get *cs */
  		"%3 = B[%1++] (Z);\n\t"	/* get *ct */
  		"CC = %2 == %3;\n\t"	/* compare a byte */
  		"if ! cc jump 2f;\n\t"	/* not equal, break out */
  		"CC = %2;\n\t"	/* at end of cs? */
  		"if cc jump 1b (bp);\n\t"	/* no, keep going */
  		"jump.s 3f;\n"	/* strings are equal */
  		"2:\t%2 = %2 - %3;\n"	/* *cs - *ct */
  		"3:\n"
  		: "=a"(cs), "=a"(ct), "=d"(__res1), "=d"(__res2)
  		: "0"(cs), "1"(ct));
  
  	return __res1;
  }
  
  int strncmp(const char *cs, const char *ct, size_t count)
  {
  	char __res1, __res2;
  
  	if (!count)
  		return 0;
  
  	__asm__(
  		"1:\t%3 = B[%0++] (Z);\n\t"	/* get *cs */
  		"%4 = B[%1++] (Z);\n\t"	/* get *ct */
  		"CC = %3 == %4;\n\t"	/* compare a byte */
  		"if ! cc jump 3f;\n\t"	/* not equal, break out */
  		"CC = %3;\n\t"	/* at end of cs? */
  		"if ! cc jump 4f;\n\t"	/* yes, all done */
  		"%2 += -1;\n\t"	/* no, adjust count */
  		"CC = %2 == 0;\n\t" "if ! cc jump 1b;\n"	/* more to do, keep going */
  		"2:\t%3 = 0;\n\t"	/* strings are equal */
  		"jump.s    4f;\n" "3:\t%3 = %3 - %4;\n"	/* *cs - *ct */
  		"4:"
  		: "=a"(cs), "=a"(ct), "=da"(count), "=d"(__res1), "=d"(__res2)
  		: "0"(cs), "1"(ct), "2"(count));
  
  	return __res1;
  }
  
  #ifdef MDMA1_D0_NEXT_DESC_PTR
  # define MDMA_D0_NEXT_DESC_PTR MDMA1_D0_NEXT_DESC_PTR
  # define MDMA_S0_NEXT_DESC_PTR MDMA1_S0_NEXT_DESC_PTR
  #endif
  
  static void dma_calc_size(unsigned long ldst, unsigned long lsrc, size_t count,
  			unsigned long *dshift, unsigned long *bpos)
  {
  	unsigned long limit;
  
  #ifdef MSIZE
  	limit = 6;
  	*dshift = MSIZE_P;
  #else
  	limit = 3;
  	*dshift = WDSIZE_P;
  #endif
  
  	*bpos = min(limit, ffs(ldst | lsrc | count)) - 1;
  }
  
  /* This version misbehaves for count values of 0 and 2^16+.
   * Perhaps we should detect that ?  Nowhere do we actually
   * use dma memcpy for those types of lengths though ...
   */
  void dma_memcpy_nocache(void *dst, const void *src, size_t count)
  {
  	struct dma_register *mdma_d0 = (void *)MDMA_D0_NEXT_DESC_PTR;
  	struct dma_register *mdma_s0 = (void *)MDMA_S0_NEXT_DESC_PTR;
  	unsigned long ldst = (unsigned long)dst;
  	unsigned long lsrc = (unsigned long)src;
  	unsigned long dshift, bpos;
  	uint32_t dsize, mod;
  
  	/* Disable DMA in case it's still running (older u-boot's did not
  	 * always turn them off).  Do it before the if statement below so
  	 * we can be cheap and not do a SSYNC() due to the forced abort.
  	 */
  	bfin_write(&mdma_d0->config, 0);
  	bfin_write(&mdma_s0->config, 0);
  	bfin_write(&mdma_d0->status, DMA_RUN | DMA_DONE | DMA_ERR);
  
  	/* Scratchpad cannot be a DMA source or destination */
  	if ((lsrc >= L1_SRAM_SCRATCH && lsrc < L1_SRAM_SCRATCH_END) ||
  	    (ldst >= L1_SRAM_SCRATCH && ldst < L1_SRAM_SCRATCH_END))
  		hang();
  
  	dma_calc_size(ldst, lsrc, count, &dshift, &bpos);
  	dsize = bpos << dshift;
  	count >>= bpos;
  	mod = 1 << bpos;
  
  #ifdef PSIZE
  	dsize |= min(3, bpos) << PSIZE_P;
  #endif
  
  	/* Copy sram functions from sdram to sram */
  	/* Setup destination start address */
  	bfin_write(&mdma_d0->start_addr, ldst);
  	/* Setup destination xcount */
  	bfin_write(&mdma_d0->x_count, count);
  	/* Setup destination xmodify */
  	bfin_write(&mdma_d0->x_modify, mod);
  
  	/* Setup Source start address */
  	bfin_write(&mdma_s0->start_addr, lsrc);
  	/* Setup Source xcount */
  	bfin_write(&mdma_s0->x_count, count);
  	/* Setup Source xmodify */
  	bfin_write(&mdma_s0->x_modify, mod);
  
  	/* Enable source DMA */
  	bfin_write(&mdma_s0->config, dsize | DMAEN);
  	bfin_write(&mdma_d0->config, dsize | DMAEN | WNR | DI_EN);
  	SSYNC();
  
  	while (!(bfin_read(&mdma_d0->status) & DMA_DONE))
  		continue;
  
  	bfin_write(&mdma_d0->status, DMA_RUN | DMA_DONE | DMA_ERR);
  	bfin_write(&mdma_d0->config, 0);
  	bfin_write(&mdma_s0->config, 0);
  }
  /* We should do a dcache invalidate on the destination after the dma, but since
   * we lack such hardware capability, we'll flush/invalidate the destination
   * before the dma and bank on the idea that u-boot is single threaded.
   */
  void *dma_memcpy(void *dst, const void *src, size_t count)
  {
  	if (dcache_status()) {
  		blackfin_dcache_flush_range(src, src + count);
  		blackfin_dcache_flush_invalidate_range(dst, dst + count);
  	}
  
  	dma_memcpy_nocache(dst, src, count);
  
  	if (icache_status())
  		blackfin_icache_flush_range(dst, dst + count);
  
  	return dst;
  }
  
  /*
   * memcpy - Copy one area of memory to another
   * @dest: Where to copy to
   * @src: Where to copy from
   * @count: The size of the area.
   *
   * We need to have this wrapper in memcpy() as common code may call memcpy()
   * to load up L1 regions.  Consider loading an ELF which has sections with
   * LMA's pointing to L1.  The common code ELF loader will simply use memcpy()
   * to move the ELF's sections into the right place.  We need to catch that
   * here and redirect to dma_memcpy().
   */
  extern void *memcpy_ASM(void *dst, const void *src, size_t count);
  void *memcpy(void *dst, const void *src, size_t count)
  {
  	if (!count)
  		return dst;
  
  #ifdef CONFIG_CMD_KGDB
  	if (src >= (void *)SYSMMR_BASE) {
  		if (count == 2 && (unsigned long)src % 2 == 0) {
  			u16 mmr = bfin_read16(src);
  			memcpy(dst, &mmr, sizeof(mmr));
  			return dst;
  		}
  		if (count == 4 && (unsigned long)src % 4 == 0) {
  			u32 mmr = bfin_read32(src);
  			memcpy(dst, &mmr, sizeof(mmr));
  			return dst;
  		}
  		/* Failed for some reason */
  		memset(dst, 0xad, count);
  		return dst;
  	}
  	if (dst >= (void *)SYSMMR_BASE) {
  		if (count == 2 && (unsigned long)dst % 2 == 0) {
  			u16 mmr;
  			memcpy(&mmr, src, sizeof(mmr));
  			bfin_write16(dst, mmr);
  			return dst;
  		}
  		if (count == 4 && (unsigned long)dst % 4 == 0) {
  			u32 mmr;
  			memcpy(&mmr, src, sizeof(mmr));
  			bfin_write32(dst, mmr);
  			return dst;
  		}
  		/* Failed for some reason */
  		memset(dst, 0xad, count);
  		return dst;
  	}
  #endif
  
  	/* if L1 is the source or dst, use DMA */
  	if (addr_bfin_on_chip_mem(dst) || addr_bfin_on_chip_mem(src))
  		return dma_memcpy(dst, src, count);
  	else
  		/* No L1 is involved, so just call regular memcpy */
  		return memcpy_ASM(dst, src, count);
  }
  