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-rw-r--r--arch/arm/lib/io-readsl.S76
1 files changed, 76 insertions, 0 deletions
diff --git a/arch/arm/lib/io-readsl.S b/arch/arm/lib/io-readsl.S
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+++ b/arch/arm/lib/io-readsl.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * linux/arch/arm/lib/io-readsl.S
+ *
+ * Copyright (C) 1995-2000 Russell King
+ */
+#include <linux/linkage.h>
+#include <asm/assembler.h>
+
+ENTRY(__raw_readsl)
+ teq r2, #0 @ do we have to check for the zero len?
+ reteq lr
+ ands ip, r1, #3
+ bne 3f
+
+ subs r2, r2, #4
+ bmi 2f
+ stmfd sp!, {r4, lr}
+1: ldr r3, [r0, #0]
+ ldr r4, [r0, #0]
+ ldr ip, [r0, #0]
+ ldr lr, [r0, #0]
+ subs r2, r2, #4
+ stmia r1!, {r3, r4, ip, lr}
+ bpl 1b
+ ldmfd sp!, {r4, lr}
+2: movs r2, r2, lsl #31
+ ldrcs r3, [r0, #0]
+ ldrcs ip, [r0, #0]
+ stmiacs r1!, {r3, ip}
+ ldrne r3, [r0, #0]
+ strne r3, [r1, #0]
+ ret lr
+
+3: ldr r3, [r0]
+ cmp ip, #2
+ mov ip, r3, get_byte_0
+ strb ip, [r1], #1
+ bgt 6f
+ mov ip, r3, get_byte_1
+ strb ip, [r1], #1
+ beq 5f
+ mov ip, r3, get_byte_2
+ strb ip, [r1], #1
+
+4: subs r2, r2, #1
+ mov ip, r3, lspull #24
+ ldrne r3, [r0]
+ orrne ip, ip, r3, lspush #8
+ strne ip, [r1], #4
+ bne 4b
+ b 8f
+
+5: subs r2, r2, #1
+ mov ip, r3, lspull #16
+ ldrne r3, [r0]
+ orrne ip, ip, r3, lspush #16
+ strne ip, [r1], #4
+ bne 5b
+ b 7f
+
+6: subs r2, r2, #1
+ mov ip, r3, lspull #8
+ ldrne r3, [r0]
+ orrne ip, ip, r3, lspush #24
+ strne ip, [r1], #4
+ bne 6b
+
+ mov r3, ip, get_byte_2
+ strb r3, [r1, #2]
+7: mov r3, ip, get_byte_1
+ strb r3, [r1, #1]
+8: mov r3, ip, get_byte_0
+ strb r3, [r1, #0]
+ ret lr
+ENDPROC(__raw_readsl)