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-rw-r--r--firmware/common/memset_a.S81
1 files changed, 81 insertions, 0 deletions
diff --git a/firmware/common/memset_a.S b/firmware/common/memset_a.S
index 9403e8d68e..b6a9ca8f71 100644
--- a/firmware/common/memset_a.S
+++ b/firmware/common/memset_a.S
@@ -18,7 +18,11 @@
****************************************************************************/
#include "config.h"
+#ifdef CPU_ARM
+ .section .icode,"ax",%progbits
+#elif
.section .icode,"ax",@progbits
+#endif
.align 2
#if CONFIG_CPU == SH7034
@@ -234,4 +238,81 @@ memset:
.end:
.size memset,.end-memset
+
+#elif defined(CPU_ARM)
+
+/* The following code is taken from the Linux kernel version 2.6.15.3
+ * linux/arch/arm/lib/memset.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ */
+
+@ .word 0
+1: subs r2, r2, #4 @ 1 do we have enough
+ blt 5f @ 1 bytes to align with?
+ cmp r3, #2 @ 1
+ strltb r1, [r0], #1 @ 1
+ strleb r1, [r0], #1 @ 1
+ strb r1, [r0], #1 @ 1
+ add r2, r2, r3 @ 1 (r2 = r2 - (4 - r3))
+/*
+ * The pointer is now aligned and the length is adjusted. Try doing the
+ * memzero again.
+ */
+
+ .global memset
+ .type memset,%function
+memset:
+ ands r3, r0, #3 @ 1 unaligned?
+ bne 1b @ 1
+/*
+ * we know that the pointer in r0 is aligned to a word boundary.
+ */
+ orr r1, r1, r1, lsl #8
+ orr r1, r1, r1, lsl #16
+ mov r3, r1
+ cmp r2, #16
+ blt 4f
+/*
+ * We need an extra register for this loop - save the return address and
+ * use the LR
+ */
+ str lr, [sp, #-4]!
+ mov ip, r1
+ mov lr, r1
+
+2: subs r2, r2, #64
+ stmgeia r0!, {r1, r3, ip, lr} @ 64 bytes at a time.
+ stmgeia r0!, {r1, r3, ip, lr}
+ stmgeia r0!, {r1, r3, ip, lr}
+ stmgeia r0!, {r1, r3, ip, lr}
+ bgt 2b
+ ldmeqfd sp!, {pc} @ Now <64 bytes to go.
+/*
+ * No need to correct the count; we're only testing bits from now on
+ */
+ tst r2, #32
+ stmneia r0!, {r1, r3, ip, lr}
+ stmneia r0!, {r1, r3, ip, lr}
+ tst r2, #16
+ stmneia r0!, {r1, r3, ip, lr}
+ ldr lr, [sp], #4
+
+4: tst r2, #8
+ stmneia r0!, {r1, r3}
+ tst r2, #4
+ strne r1, [r0], #4
+/*
+ * When we get here, we've got less than 4 bytes to zero. We
+ * may have an unaligned pointer as well.
+ */
+5: tst r2, #2
+ strneb r1, [r0], #1
+ strneb r1, [r0], #1
+ tst r2, #1
+ strneb r1, [r0], #1
+ mov pc, lr
+end:
+ .size memset,.end-memset
#endif
+