lib_blackfin/string.c

   1 /*
   2  * U-boot - string.c Contains library routines.
   3  *
   4  * Copyright (c) 2005-2008 Analog Devices Inc.
   5  *
   6  * (C) Copyright 2000-2004
   7  * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
   8  *
   9  * See file CREDITS for list of people who contributed to this
  10  * project.
  11  *
  12  * This program is free software; you can redistribute it and/or
  13  * modify it under the terms of the GNU General Public License as
  14  * published by the Free Software Foundation; either version 2 of
  15  * the License, or (at your option) any later version.
  16  *
  17  * This program is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU General Public License
  23  * along with this program; if not, write to the Free Software
  24  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  25  * MA 02110-1301 USA
  26  */
  27
  28 #include <common.h>
  29 #include <config.h>
  30 #include <asm/blackfin.h>
  31 #include <asm/io.h>
  32 #include <asm/mach-common/bits/dma.h>
  33
  34 char *strcpy(char *dest, const char *src)
  35 {
  36         char *xdest = dest;
  37         char temp = 0;
  38
  39         __asm__ __volatile__ (
  40                 "1:\t%2 = B [%1++] (Z);\n\t"
  41                 "B [%0++] = %2;\n\t"
  42                 "CC = %2;\n\t"
  43                 "if cc jump 1b (bp);\n"
  44                 : "=a"(dest), "=a"(src), "=d"(temp)
  45                 : "0"(dest), "1"(src), "2"(temp)
  46                 : "memory");
  47
  48         return xdest;
  49 }
  50
  51 char *strncpy(char *dest, const char *src, size_t n)
  52 {
  53         char *xdest = dest;
  54         char temp = 0;
  55
  56         if (n == 0)
  57                 return xdest;
  58
  59         __asm__ __volatile__ (
  60                 "1:\t%3 = B [%1++] (Z);\n\t"
  61                 "B [%0++] = %3;\n\t"
  62                 "CC = %3;\n\t"
  63                 "if ! cc jump 2f;\n\t"
  64                 "%2 += -1;\n\t"
  65                 "CC = %2 == 0;\n\t"
  66                 "if ! cc jump 1b (bp);\n"
  67                 "2:\n"
  68                 : "=a"(dest), "=a"(src), "=da"(n), "=d"(temp)
  69                 : "0"(dest), "1"(src), "2"(n), "3"(temp)
  70                 : "memory");
  71
  72         return xdest;
  73 }
  74
  75 int strcmp(const char *cs, const char *ct)
  76 {
  77         char __res1, __res2;
  78
  79         __asm__ (
  80                 "1:\t%2 = B[%0++] (Z);\n\t"     /* get *cs */
  81                 "%3 = B[%1++] (Z);\n\t" /* get *ct */
  82                 "CC = %2 == %3;\n\t"    /* compare a byte */
  83                 "if ! cc jump 2f;\n\t"  /* not equal, break out */
  84                 "CC = %2;\n\t"  /* at end of cs? */
  85                 "if cc jump 1b (bp);\n\t"       /* no, keep going */
  86                 "jump.s 3f;\n"  /* strings are equal */
  87                 "2:\t%2 = %2 - %3;\n"   /* *cs - *ct */
  88                 "3:\n"
  89                 : "=a"(cs), "=a"(ct), "=d"(__res1), "=d"(__res2)
  90                 : "0"(cs), "1"(ct));
  91
  92         return __res1;
  93 }
  94
  95 int strncmp(const char *cs, const char *ct, size_t count)
  96 {
  97         char __res1, __res2;
  98
  99         if (!count)
 100                 return 0;
 101
 102         __asm__(
 103                 "1:\t%3 = B[%0++] (Z);\n\t"     /* get *cs */
 104                 "%4 = B[%1++] (Z);\n\t" /* get *ct */
 105                 "CC = %3 == %4;\n\t"    /* compare a byte */
 106                 "if ! cc jump 3f;\n\t"  /* not equal, break out */
 107                 "CC = %3;\n\t"  /* at end of cs? */
 108                 "if ! cc jump 4f;\n\t"  /* yes, all done */
 109                 "%2 += -1;\n\t" /* no, adjust count */
 110                 "CC = %2 == 0;\n\t" "if ! cc jump 1b;\n"        /* more to do, keep going */
 111                 "2:\t%3 = 0;\n\t"       /* strings are equal */
 112                 "jump.s    4f;\n" "3:\t%3 = %3 - %4;\n" /* *cs - *ct */
 113                 "4:"
 114                 : "=a"(cs), "=a"(ct), "=da"(count), "=d"(__res1), "=d"(__res2)
 115                 : "0"(cs), "1"(ct), "2"(count));
 116
 117         return __res1;
 118 }
 119
 120 #ifdef bfin_write_MDMA1_D0_IRQ_STATUS
 121 # define bfin_write_MDMA_D0_IRQ_STATUS bfin_write_MDMA1_D0_IRQ_STATUS
 122 # define bfin_write_MDMA_D0_START_ADDR bfin_write_MDMA1_D0_START_ADDR
 123 # define bfin_write_MDMA_D0_X_COUNT    bfin_write_MDMA1_D0_X_COUNT
 124 # define bfin_write_MDMA_D0_X_MODIFY   bfin_write_MDMA1_D0_X_MODIFY
 125 # define bfin_write_MDMA_D0_CONFIG     bfin_write_MDMA1_D0_CONFIG
 126 # define bfin_write_MDMA_S0_START_ADDR bfin_write_MDMA1_S0_START_ADDR
 127 # define bfin_write_MDMA_S0_X_COUNT    bfin_write_MDMA1_S0_X_COUNT
 128 # define bfin_write_MDMA_S0_X_MODIFY   bfin_write_MDMA1_S0_X_MODIFY
 129 # define bfin_write_MDMA_S0_CONFIG     bfin_write_MDMA1_S0_CONFIG
 130 # define bfin_write_MDMA_D0_IRQ_STATUS bfin_write_MDMA1_D0_IRQ_STATUS
 131 # define bfin_read_MDMA_D0_IRQ_STATUS  bfin_read_MDMA1_D0_IRQ_STATUS
 132 #endif
 133 /* This version misbehaves for count values of 0 and 2^16+.
 134  * Perhaps we should detect that ?  Nowhere do we actually
 135  * use dma memcpy for those types of lengths though ...
 136  */
 137 void dma_memcpy_nocache(void *dst, const void *src, size_t count)
 138 {
 139         uint16_t wdsize, mod;
 140
 141         /* Disable DMA in case it's still running (older u-boot's did not
 142          * always turn them off).  Do it before the if statement below so
 143          * we can be cheap and not do a SSYNC() due to the forced abort.
 144          */
 145         bfin_write_MDMA_D0_CONFIG(0);
 146         bfin_write_MDMA_S0_CONFIG(0);
 147         bfin_write_MDMA_D0_IRQ_STATUS(DMA_RUN | DMA_DONE | DMA_ERR);
 148
 149         /* Scratchpad cannot be a DMA source or destination */
 150         if (((unsigned long)src >= L1_SRAM_SCRATCH &&
 151              (unsigned long)src < L1_SRAM_SCRATCH_END) ||
 152             ((unsigned long)dst >= L1_SRAM_SCRATCH &&
 153              (unsigned long)dst < L1_SRAM_SCRATCH_END))
 154                 hang();
 155
 156         if (((unsigned long)dst | (unsigned long)src | count) & 0x1) {
 157                 wdsize = WDSIZE_8;
 158                 mod = 1;
 159         } else if (((unsigned long)dst | (unsigned long)src | count) & 0x2) {
 160                 wdsize = WDSIZE_16;
 161                 count >>= 1;
 162                 mod = 2;
 163         } else {
 164                 wdsize = WDSIZE_32;
 165                 count >>= 2;
 166                 mod = 4;
 167         }
 168
 169         /* Copy sram functions from sdram to sram */
 170         /* Setup destination start address */
 171         bfin_write_MDMA_D0_START_ADDR(dst);
 172         /* Setup destination xcount */
 173         bfin_write_MDMA_D0_X_COUNT(count);
 174         /* Setup destination xmodify */
 175         bfin_write_MDMA_D0_X_MODIFY(mod);
 176
 177         /* Setup Source start address */
 178         bfin_write_MDMA_S0_START_ADDR(src);
 179         /* Setup Source xcount */
 180         bfin_write_MDMA_S0_X_COUNT(count);
 181         /* Setup Source xmodify */
 182         bfin_write_MDMA_S0_X_MODIFY(mod);
 183
 184         /* Enable source DMA */
 185         bfin_write_MDMA_S0_CONFIG(wdsize | DMAEN);
 186         bfin_write_MDMA_D0_CONFIG(wdsize | DMAEN | WNR | DI_EN);
 187         SSYNC();
 188
 189         while (!(bfin_read_MDMA_D0_IRQ_STATUS() & DMA_DONE))
 190                 continue;
 191
 192         bfin_write_MDMA_D0_IRQ_STATUS(DMA_RUN | DMA_DONE | DMA_ERR);
 193         bfin_write_MDMA_D0_CONFIG(0);
 194         bfin_write_MDMA_S0_CONFIG(0);
 195 }
 196 /* We should do a dcache invalidate on the destination after the dma, but since
 197  * we lack such hardware capability, we'll flush/invalidate the destination
 198  * before the dma and bank on the idea that u-boot is single threaded.
 199  */
 200 void *dma_memcpy(void *dst, const void *src, size_t count)
 201 {
 202         if (dcache_status()) {
 203                 blackfin_dcache_flush_range(src, src + count);
 204                 blackfin_dcache_flush_invalidate_range(dst, dst + count);
 205         }
 206
 207         dma_memcpy_nocache(dst, src, count);
 208
 209         if (icache_status())
 210                 blackfin_icache_flush_range(dst, dst + count);
 211
 212         return dst;
 213 }
 214
 215 /*
 216  * memcpy - Copy one area of memory to another
 217  * @dest: Where to copy to
 218  * @src: Where to copy from
 219  * @count: The size of the area.
 220  *
 221  * We need to have this wrapper in memcpy() as common code may call memcpy()
 222  * to load up L1 regions.  Consider loading an ELF which has sections with
 223  * LMA's pointing to L1.  The common code ELF loader will simply use memcpy()
 224  * to move the ELF's sections into the right place.  We need to catch that
 225  * here and redirect to dma_memcpy().
 226  */
 227 extern void *memcpy_ASM(void *dst, const void *src, size_t count);
 228 void *memcpy(void *dst, const void *src, size_t count)
 229 {
 230         if (!count)
 231                 return dst;
 232
 233 #ifdef CONFIG_CMD_KGDB
 234         if (src >= (void *)SYSMMR_BASE) {
 235                 if (count == 2 && (unsigned long)src % 2 == 0) {
 236                         u16 mmr = bfin_read16(src);
 237                         memcpy(dst, &mmr, sizeof(mmr));
 238                         return dst;
 239                 }
 240                 if (count == 4 && (unsigned long)src % 4 == 0) {
 241                         u32 mmr = bfin_read32(src);
 242                         memcpy(dst, &mmr, sizeof(mmr));
 243                         return dst;
 244                 }
 245                 /* Failed for some reason */
 246                 memset(dst, 0xad, count);
 247                 return dst;
 248         }
 249         if (dst >= (void *)SYSMMR_BASE) {
 250                 if (count == 2 && (unsigned long)dst % 2 == 0) {
 251                         u16 mmr;
 252                         memcpy(&mmr, src, sizeof(mmr));
 253                         bfin_write16(dst, mmr);
 254                         return dst;
 255                 }
 256                 if (count == 4 && (unsigned long)dst % 4 == 0) {
 257                         u32 mmr;
 258                         memcpy(&mmr, src, sizeof(mmr));
 259                         bfin_write32(dst, mmr);
 260                         return dst;
 261                 }
 262                 /* Failed for some reason */
 263                 memset(dst, 0xad, count);
 264                 return dst;
 265         }
 266 #endif
 267
 268         /* if L1 is the source or dst, use DMA */
 269         if (addr_bfin_on_chip_mem(dst) || addr_bfin_on_chip_mem(src))
 270                 return dma_memcpy(dst, src, count);
 271         else
 272                 /* No L1 is involved, so just call regular memcpy */
 273                 return memcpy_ASM(dst, src, count);
 274 }