Merge "Revert "libc/memset: Implement function in assembler"" into integration

lib/libc/aarch32/memset.S

-/*
- * Copyright (c) 2020, Arm Limited. All rights reserved.
- *
- * SPDX-License-Identifier: BSD-3-Clause
- */
-
-#include <asm_macros.S>
-
-	.syntax unified
-	.global	memset
-
-/* -----------------------------------------------------------------------
- * void memset(void *dst, int val, size_t count)
- *
- * Copy the value of 'val' (converted to an unsigned char) into
- * each of the first 'count' characters of the object pointed to by 'dst'.
- *
- * Returns the value of 'dst'.
- * -----------------------------------------------------------------------
- */
-func memset
-	cmp	r2, #0
-	bxeq	lr			/* return if 'count' = 0 */
-	mov	r12, r0			/* keep r0 */
-	tst	r0, #3
-	beq	aligned			/* 4-bytes aligned */
-
-	/* Unaligned 'dst' */
-unaligned:
-	strb	r1, [r12], #1
-	subs	r2, r2, #1
-	bxeq	lr			/* return if 0 */
-	tst	r12, #3
-	bne	unaligned		/* continue while unaligned */
-
-	/* 4-bytes aligned */
-aligned:bfi	r1, r1, #8, #8		/* propagate 'val' */
-	bfi	r1, r1, #16, #16
-
-	mov	r3, r1
-
-	cmp	r2, #16
-	blo	less_16
-
-	push	{r4, lr}
-	mov	r4, r1
-	mov	lr, r1
-
-	cmp	r2, #32
-	blo	less_32
-
-write_32:
-	stmia	r12!, {r1, r3, r4, lr}	/* write 32 bytes in a loop */
-	stmia	r12!, {r1, r3, r4, lr}
-	subs	r2, r2, #32
-	popeq	{r4, pc}		/* return if 0 */
-	cmp	r2, #32
-	bhs	write_32
-
-less_32:cmp	r2, #16
-	stmiahs	r12!, {r1, r3, r4, lr}	/* write 16 bytes */
-	popeq	{r4, pc}		/* return if 16 */
-	pop	{r4, lr}
-
-less_16:lsls	r2, r2, #29		/* C = r2[3]; N = r2[2]; Z = r2[2:0] */
-	stmiacs	r12!, {r1, r3}		/* write 8 bytes */
-	bxeq	lr			/* return if 8 */
-	strmi	r1, [r12], #4		/* write 4 bytes */
-	lsls	r2, r2, #1		/* N = r2[1]; Z = r2[0] */
-	strhmi	r1, [r12], #2		/* write 2 bytes */
-	strbne	r1, [r12]		/* write 1 byte */
-	bx	lr
-
-endfunc memset

lib/libc/aarch64/memset.S

-/*
- * Copyright (c) 2020, Arm Limited. All rights reserved.
- *
- * SPDX-License-Identifier: BSD-3-Clause
- */
-
-#include <asm_macros.S>
-
-	.global	memset
-
-/* -----------------------------------------------------------------------
- * void memset(void *dst, int val, size_t count)
- *
- * Copy the value of 'val' (converted to an unsigned char) into
- * each of the first 'count' characters of the object pointed to by 'dst'.
- *
- * Returns the value of 'dst'.
- * -----------------------------------------------------------------------
- */
-func memset
-	cbz	w2, exit		/* exit if 'count' = 0 */
-	mov	x3, x0			/* keep x0 */
-	tst	x0, #7
-	b.eq	aligned			/* 8-bytes aligned */
-
-	/* Unaligned 'dst' */
-unaligned:
-	strb	w1, [x3], #1
-	subs	w2, w2, #1
-	b.eq	exit			/* exit if 0 */
-	tst	x3, #7
-	b.ne	unaligned		/* continue while unaligned */
-
-	/* 8-bytes aligned */
-aligned:cbz	x1, x1_zero
-	bfi	w1, w1, #8, #8		/* propagate 'val' */
-	bfi	w1, w1, #16, #16
-	bfi	x1, x1, #32, #32
-
-x1_zero:ands	w4, w2, #~0x3f
-	b.eq	less_64
-
-write_64:
-	.rept	4
-	stp	x1, x1, [x3], #16	/* write 64 bytes in a loop */
-	.endr
-	subs	w4, w4, #64
-	b.ne	write_64
-	ands	w2, w2, #0x3f
-	b.eq	exit			/* exit if 0 */
-
-less_64:tbz	w2, #5, less_32		/* < 32 bytes */
-	stp	x1, x1, [x3], #16	/* write 32 bytes */
-	stp	x1, x1, [x3], #16
-	ands	w2, w2, #0x1f
-	b.eq	exit
-
-less_32:tbz	w2, #4, less_16		/* < 16 bytes */
-	stp	x1, x1, [x3], #16	/* write 16 bytes */
-	ands	w2, w2, #0xf
-	b.eq	exit
-
-less_16:tbz	w2, #3, less_8		/* < 8 bytes */
-	str	x1, [x3], #8		/* write 8 bytes */
-	ands	w2, w2, #7
-	b.eq	exit
-
-less_8:	tbz	w2, #2, less_4		/* < 4 bytes */
-	str	w1, [x3], #4		/* write 4 bytes */
-	ands	w2, w2, #3
-	b.eq	exit
-
-less_4:	tbz	w2, #1, less_2		/* < 2 bytes */
-	strh	w1, [x3], #2		/* write 2 bytes */
-	tbz	w2, #0, exit
-less_2:	strb	w1, [x3]		/* write 1 byte */
-exit:	ret
-
-endfunc	memset

lib/libc/libc.mk

 #
-# Copyright (c) 2016-2020, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2016-2019, ARM Limited and Contributors. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
 #
@@ -13,6 +13,7 @@ LIBC_SRCS	:=	$(addprefix lib/libc/,		\
 			memcpy.c			\
 			memmove.c			\
 			memrchr.c			\
+			memset.c			\
 			printf.c			\
 			putchar.c			\
 			puts.c				\
@@ -27,14 +28,8 @@ LIBC_SRCS	:=	$(addprefix lib/libc/,		\
 
 ifeq (${ARCH},aarch64)
 LIBC_SRCS	+=	$(addprefix lib/libc/aarch64/,	\
-			memset.S			\
 			setjmp.S)
 endif
 
-ifeq (${ARCH},aarch32)
-LIBC_SRCS	+=	$(addprefix lib/libc/aarch32/,	\
-			memset.S)
-endif
-
 INCLUDES	+=	-Iinclude/lib/libc		\
 			-Iinclude/lib/libc/$(ARCH)	\

lib/libc/memset.c

+/*
+ * Copyright (c) 2013-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <stddef.h>
+#include <string.h>
+
+void *memset(void *dst, int val, size_t count)
+{
+	char *ptr = dst;
+
+	while (count--)
+		*ptr++ = val;
+
+	return dst;
+}

plat/nvidia/tegra/platform.mk

 #
-# Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
+# Copyright (c) 2015-2019, ARM Limited and Contributors. All rights reserved.
 # Copyright (c) 2020, NVIDIA Corporation. All rights reserved.
 #
 # SPDX-License-Identifier: BSD-3-Clause
@@ -69,11 +69,11 @@ TF_CFLAGS	+= -Wsign-compare -nostdlib
 
 # override with necessary libc files for the Tegra platform
 override LIBC_SRCS :=	$(addprefix lib/libc/,		\
-			aarch64/memset.S		\
 			aarch64/setjmp.S		\
 			assert.c			\
 			memcpy.c			\
 			memmove.c			\
+			memset.c			\
 			printf.c			\
 			putchar.c			\
 			strlen.c			\