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-rw-r--r--kernel/arch/arm/lib/io-readsw-armv4.S131
1 files changed, 131 insertions, 0 deletions
diff --git a/kernel/arch/arm/lib/io-readsw-armv4.S b/kernel/arch/arm/lib/io-readsw-armv4.S
new file mode 100644
index 000000000..d9a45e969
--- /dev/null
+++ b/kernel/arch/arm/lib/io-readsw-armv4.S
@@ -0,0 +1,131 @@
+/*
+ * linux/arch/arm/lib/io-readsw-armv4.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+ .macro pack, rd, hw1, hw2
+#ifndef __ARMEB__
+ orr \rd, \hw1, \hw2, lsl #16
+#else
+ orr \rd, \hw2, \hw1, lsl #16
+#endif
+ .endm
+
+.Linsw_align: movs ip, r1, lsl #31
+ bne .Linsw_noalign
+ ldrh ip, [r0]
+ sub r2, r2, #1
+ strh ip, [r1], #2
+
+ENTRY(__raw_readsw)
+ teq r2, #0
+ reteq lr
+ tst r1, #3
+ bne .Linsw_align
+
+ stmfd sp!, {r4, r5, lr}
+
+ subs r2, r2, #8
+ bmi .Lno_insw_8
+
+.Linsw_8_lp: ldrh r3, [r0]
+ ldrh r4, [r0]
+ pack r3, r3, r4
+
+ ldrh r4, [r0]
+ ldrh r5, [r0]
+ pack r4, r4, r5
+
+ ldrh r5, [r0]
+ ldrh ip, [r0]
+ pack r5, r5, ip
+
+ ldrh ip, [r0]
+ ldrh lr, [r0]
+ pack ip, ip, lr
+
+ subs r2, r2, #8
+ stmia r1!, {r3 - r5, ip}
+ bpl .Linsw_8_lp
+
+.Lno_insw_8: tst r2, #4
+ beq .Lno_insw_4
+
+ ldrh r3, [r0]
+ ldrh r4, [r0]
+ pack r3, r3, r4
+
+ ldrh r4, [r0]
+ ldrh ip, [r0]
+ pack r4, r4, ip
+
+ stmia r1!, {r3, r4}
+
+.Lno_insw_4: movs r2, r2, lsl #31
+ bcc .Lno_insw_2
+
+ ldrh r3, [r0]
+ ldrh ip, [r0]
+ pack r3, r3, ip
+ str r3, [r1], #4
+
+.Lno_insw_2: ldrneh r3, [r0]
+ strneh r3, [r1]
+
+ ldmfd sp!, {r4, r5, pc}
+
+#ifdef __ARMEB__
+#define _BE_ONLY_(code...) code
+#define _LE_ONLY_(code...)
+#define push_hbyte0 lsr #8
+#define pull_hbyte1 lsl #24
+#else
+#define _BE_ONLY_(code...)
+#define _LE_ONLY_(code...) code
+#define push_hbyte0 lsl #24
+#define pull_hbyte1 lsr #8
+#endif
+
+.Linsw_noalign: stmfd sp!, {r4, lr}
+ ldrccb ip, [r1, #-1]!
+ bcc 1f
+
+ ldrh ip, [r0]
+ sub r2, r2, #1
+ _BE_ONLY_( mov ip, ip, ror #8 )
+ strb ip, [r1], #1
+ _LE_ONLY_( mov ip, ip, lsr #8 )
+ _BE_ONLY_( mov ip, ip, lsr #24 )
+
+1: subs r2, r2, #2
+ bmi 3f
+ _BE_ONLY_( mov ip, ip, lsl #24 )
+
+2: ldrh r3, [r0]
+ ldrh r4, [r0]
+ subs r2, r2, #2
+ orr ip, ip, r3, lsl #8
+ orr ip, ip, r4, push_hbyte0
+ str ip, [r1], #4
+ mov ip, r4, pull_hbyte1
+ bpl 2b
+
+ _BE_ONLY_( mov ip, ip, lsr #24 )
+
+3: tst r2, #1
+ strb ip, [r1], #1
+ ldrneh ip, [r0]
+ _BE_ONLY_( movne ip, ip, ror #8 )
+ strneb ip, [r1], #1
+ _LE_ONLY_( movne ip, ip, lsr #8 )
+ _BE_ONLY_( movne ip, ip, lsr #24 )
+ strneb ip, [r1]
+ ldmfd sp!, {r4, pc}
+ENDPROC(__raw_readsw)