1 files changed, 196 insertions, 0 deletions

diff --git a/firmware/common/memcpy_a.S b/firmware/common/memcpy_a.S
new file mode 100644
index 0000000000..e129b99442
--- /dev/null
+++ b/firmware/common/memcpy_a.S
@@ -0,0 +1,196 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2004 by Jens Arnold
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+#include "config.h"
+
+    .section    .icode,"ax",@progbits
+
+#if CONFIG_CPU == SH7034
+    .align      2
+    .global     _memcpy
+    .type       _memcpy,@function
+
+/* Copies <length> bytes of data in memory from <source> to <dest>
+ * This version is optimized for speed
+ *
+ * arguments:
+ *  r4 - destination address
+ *  r5 - source address
+ *  r6 - length
+ *
+ * return value:
+ *  r0 - destination address (like ANSI version)
+ *
+ * register usage:
+ *  r0 - data / temporary
+ *  r1 - bit mask for rounding to long bounds / 2nd data
+ *  r2 - first long bound (only if >= 12 bytes)
+ *  r3 - last long bound (-4) (only if >= 12 bytes)
+ *  r4 - current dest address
+ *  r5 - current source address
+ *  r6 - source end address
+ *  r7 - stored dest start address
+ *
+ * The instruction order below is devised in a way to utilize the pipelining
+ * of the SH1 to the max. The routine also tries to utilize fast page mode.
+ */
+
+_memcpy:
+    add     r5,r6       /* r6 = source_end */
+    mov     r4,r7       /* store for returning */
+    add     #-8,r4      /* adjust for early increments (max. 2 longs) */
+
+    mov     r6,r0
+    add     #-12,r0     /* r0 = r6 - 12; don't go below 12 here! */
+    cmp/hs  r5,r0       /* >= 12 bytes to copy? */
+    bf      .start_b2   /* no, jump into byte loop */
+
+    mov     #-4,r1      /* r1 = 0xFFFFFFFC */
+
+    mov     r5,r2
+    add     #3,r2
+    and     r1,r2       /* r2 = first source long bound */
+    mov     r6,r3
+    add     #-4,r3      /* end offset for copying 2 longs per pass */
+    bra     .start_b1   /* jump into leading byte loop */
+    and     r1,r3       /* r3 = last source long bound - 4 */
+
+    /* leading byte loop: copies 0..3 bytes */
+    .align  2
+.loop_b1:
+    mov.b   @r5+,r0     /* load byte & increment source addr */
+    add     #1,r4       /* increment dest addr */
+    mov.b   r0,@(7,r4)  /* store byte */
+.start_b1:
+    cmp/hi  r5,r2       /* runs r5 up to first long bound */
+    bt      .loop_b1
+    /* now r5 is always at a long boundary */
+    /* -> memory reading is done in longs for all dest alignments */
+
+    /* selector for main copy loop */
+    mov     r4,r0
+    tst     #3,r0       /* dest now also at long bound? */
+    bt      .loop2_l    /* yes, do long copy */
+    tst     #1,r0       /* dest now at least at word bound? */
+    bt      .start4_w   /* yes, do word copy */
+
+    /* main loop for byte aligned destination (fast) */
+    /* copies 1 long per pass */
+    add     #4,r3       /* reset end offset */
+    add     #-1,r4      /* adjust to word alignment for word write+ */
+
+.loop4_b:
+    mov.l   @r5+,r0     /* load a long & increment source addr */
+    add     #4,r4       /* increment dest addr */
+    mov.b   r0,@(8,r4)  /* store low byte */
+    shlr8   r0          /* get middle 2 bytes */
+    mov.w   r0,@(6,r4)  /* store as word+ */
+    shlr16  r0          /* get upper byte */
+    mov.b   r0,@(5,r4)  /* and store */
+    cmp/hi  r5,r3       /* runs r5 up to last long bound */
+    bt      .loop4_b
+
+    bra     .start_b2   /* jump to trailing byte loop */
+    add     #1,r4       /* readjust */
+
+    /* main loop for word aligned destination (faster) */
+    /* copies 2 longs per pass, utilizing fast page mode */
+.start4_w:
+    add     #-2,r4      /* adjust to long alignment for long write+ */
+
+.loop4_w:
+    mov.l   @r5+,r1     /* load first long & increment source addr */
+    add     #8,r4       /* increment dest addr */
+    mov.l   @r5+,r0     /* load second long & increment source addr */
+    cmp/hi  r5,r3       /* runs r5 up to last or second last long bound */
+    mov.w   r0,@(8,r4)  /* store low word of second long */
+    xtrct   r1,r0       /* extract low word of first long & high word of second long */
+    mov.l   r0,@(4,r4)  /* and store as long+ */
+    swap.w  r1,r0       /* get high word of first long */
+    mov.w   r0,@(2,r4)  /* and store it */
+    bt      .loop4_w
+
+    add     #2,r4       /* readjust destination */
+    add     #4,r3       /* reset end offset */
+    cmp/hi  r5,r3       /* one long left? */
+    bf      .start_b2   /* no, jump to trailing byte loop */
+
+    mov.l   @r5+,r0     /* load last long & increment source addr */
+    add     #4,r4       /* increment dest addr */
+    mov.w   r0,@(6,r4)  /* store low word */
+    shlr16  r0          /* get high word */
+    bra     .start_b2   /* jump to trailing byte loop */
+    mov.w   r0,@(4,r4)  /* and store it */
+
+    /* main loop for long aligned destination (fastest) */
+    /* copies 2 longs per pass, utilizing fast page mode */
+.loop2_l:
+    mov.l   @r5+,r1     /* load first long & increment source addr */
+    add     #8,r4       /* increment dest addr */
+    mov.l   @r5+,r0     /* load second long & increment source addr */
+    cmp/hi  r5,r3       /* runs r5 up to last or second last long bound */
+    mov.l   r1,@r4      /* store first long */
+    mov.l   r0,@(4,r4)  /* store second long; NOT ALIGNED - no speed loss here! */
+    bt      .loop2_l
+
+    add     #4,r3       /* reset end offset */
+    cmp/hi  r5,r3       /* one long left? */
+    bf      .start_b2   /* no, jump to trailing byte loop */
+
+    mov.l   @r5+,r0     /* load last long & increment source addr */
+    add     #4,r4       /* increment dest addr */
+    bra     .start_b2   /* jump to trailing byte loop */
+    mov.l   r0,@(4,r4)  /* store last long */
+
+    /* trailing byte loop: copies 0..3 bytes (or all for < 12 in total) */
+.loop_b2:
+    mov.b   @r5+,r0     /* load byte & increment source addr */
+    add     #1,r4       /* increment dest addr */
+    mov.b   r0,@(7,r4)  /* store byte */
+.start_b2:
+    cmp/hi  r5,r6       /* runs r5 up to end address */
+    bt      .loop_b2
+
+    rts
+    mov     r7,r0       /* return dest start address */
+.end:
+    .size   _memcpy,.end-_memcpy
+#elif CONFIG_CPU == MCF5249
+    .align      2
+    .global     memcpy
+    .type       memcpy,@function
+
+/* Copies <length> bytes of data in memory from <source> to <dest>
+ * This version is not optimized at all
+ */
+memcpy:
+        move.l  (4,%sp),%a1    /* Destination */
+        move.l  (8,%sp),%a0     /* Source */
+        move.l  (12,%sp),%d1    /* Length */
+
+        cmp.l   #0,%d1
+        bra.b   .byteloopend
+
+.byteloop:
+        move.b  (%a0)+,(%a1)+
+        subq.l  #1,%d1
+.byteloopend:
+        bne.b   .byteloop
+
+        rts
+#endif