v4.19.13 snapshot.
diff --git a/arch/mips/lib/memset.S b/arch/mips/lib/memset.S
new file mode 100644
index 0000000..069acec
--- /dev/null
+++ b/arch/mips/lib/memset.S
@@ -0,0 +1,328 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (C) 1998, 1999, 2000 by Ralf Baechle
+ * Copyright (C) 1999, 2000 Silicon Graphics, Inc.
+ * Copyright (C) 2007 by Maciej W. Rozycki
+ * Copyright (C) 2011, 2012 MIPS Technologies, Inc.
+ */
+#include <asm/asm.h>
+#include <asm/asm-offsets.h>
+#include <asm/export.h>
+#include <asm/regdef.h>
+
+#if LONGSIZE == 4
+#define LONG_S_L swl
+#define LONG_S_R swr
+#else
+#define LONG_S_L sdl
+#define LONG_S_R sdr
+#endif
+
+#ifdef CONFIG_CPU_MICROMIPS
+#define STORSIZE (LONGSIZE * 2)
+#define STORMASK (STORSIZE - 1)
+#define FILL64RG t8
+#define FILLPTRG t7
+#undef  LONG_S
+#define LONG_S LONG_SP
+#else
+#define STORSIZE LONGSIZE
+#define STORMASK LONGMASK
+#define FILL64RG a1
+#define FILLPTRG t0
+#endif
+
+#define LEGACY_MODE 1
+#define EVA_MODE    2
+
+/*
+ * No need to protect it with EVA #ifdefery. The generated block of code
+ * will never be assembled if EVA is not enabled.
+ */
+#define __EVAFY(insn, reg, addr) __BUILD_EVA_INSN(insn##e, reg, addr)
+#define ___BUILD_EVA_INSN(insn, reg, addr) __EVAFY(insn, reg, addr)
+
+#define EX(insn,reg,addr,handler)			\
+	.if \mode == LEGACY_MODE;			\
+9:		insn	reg, addr;			\
+	.else;						\
+9:		___BUILD_EVA_INSN(insn, reg, addr);	\
+	.endif;						\
+	.section __ex_table,"a";			\
+	PTR	9b, handler;				\
+	.previous
+
+	.macro	f_fill64 dst, offset, val, fixup, mode
+	EX(LONG_S, \val, (\offset +  0 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset +  1 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset +  2 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset +  3 * STORSIZE)(\dst), \fixup)
+#if ((defined(CONFIG_CPU_MICROMIPS) && (LONGSIZE == 4)) || !defined(CONFIG_CPU_MICROMIPS))
+	EX(LONG_S, \val, (\offset +  4 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset +  5 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset +  6 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset +  7 * STORSIZE)(\dst), \fixup)
+#endif
+#if (!defined(CONFIG_CPU_MICROMIPS) && (LONGSIZE == 4))
+	EX(LONG_S, \val, (\offset +  8 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset +  9 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset + 10 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset + 11 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset + 12 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset + 13 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset + 14 * STORSIZE)(\dst), \fixup)
+	EX(LONG_S, \val, (\offset + 15 * STORSIZE)(\dst), \fixup)
+#endif
+	.endm
+
+	.set	noreorder
+	.align	5
+
+	/*
+	 * Macro to generate the __bzero{,_user} symbol
+	 * Arguments:
+	 * mode: LEGACY_MODE or EVA_MODE
+	 */
+	.macro __BUILD_BZERO mode
+	/* Initialize __memset if this is the first time we call this macro */
+	.ifnotdef __memset
+	.set __memset, 1
+	.hidden __memset /* Make sure it does not leak */
+	.endif
+
+	sltiu		t0, a2, STORSIZE	/* very small region? */
+	bnez		t0, .Lsmall_memset\@
+	 andi		t0, a0, STORMASK	/* aligned? */
+
+#ifdef CONFIG_CPU_MICROMIPS
+	move		t8, a1			/* used by 'swp' instruction */
+	move		t9, a1
+#endif
+#ifndef CONFIG_CPU_DADDI_WORKAROUNDS
+	beqz		t0, 1f
+	 PTR_SUBU	t0, STORSIZE		/* alignment in bytes */
+#else
+	.set		noat
+	li		AT, STORSIZE
+	beqz		t0, 1f
+	 PTR_SUBU	t0, AT			/* alignment in bytes */
+	.set		at
+#endif
+
+#ifndef CONFIG_CPU_MIPSR6
+	R10KCBARRIER(0(ra))
+#ifdef __MIPSEB__
+	EX(LONG_S_L, a1, (a0), .Lfirst_fixup\@)	/* make word/dword aligned */
+#else
+	EX(LONG_S_R, a1, (a0), .Lfirst_fixup\@)	/* make word/dword aligned */
+#endif
+	PTR_SUBU	a0, t0			/* long align ptr */
+	PTR_ADDU	a2, t0			/* correct size */
+
+#else /* CONFIG_CPU_MIPSR6 */
+#define STORE_BYTE(N)				\
+	EX(sb, a1, N(a0), .Lbyte_fixup\@);	\
+	beqz		t0, 0f;			\
+	PTR_ADDU	t0, 1;
+
+	PTR_ADDU	a2, t0			/* correct size */
+	PTR_ADDU	t0, 1
+	STORE_BYTE(0)
+	STORE_BYTE(1)
+#if LONGSIZE == 4
+	EX(sb, a1, 2(a0), .Lbyte_fixup\@)
+#else
+	STORE_BYTE(2)
+	STORE_BYTE(3)
+	STORE_BYTE(4)
+	STORE_BYTE(5)
+	EX(sb, a1, 6(a0), .Lbyte_fixup\@)
+#endif
+0:
+	ori		a0, STORMASK
+	xori		a0, STORMASK
+	PTR_ADDIU	a0, STORSIZE
+#endif /* CONFIG_CPU_MIPSR6 */
+1:	ori		t1, a2, 0x3f		/* # of full blocks */
+	xori		t1, 0x3f
+	beqz		t1, .Lmemset_partial\@	/* no block to fill */
+	 andi		t0, a2, 0x40-STORSIZE
+
+	PTR_ADDU	t1, a0			/* end address */
+	.set		reorder
+1:	PTR_ADDIU	a0, 64
+	R10KCBARRIER(0(ra))
+	f_fill64 a0, -64, FILL64RG, .Lfwd_fixup\@, \mode
+	bne		t1, a0, 1b
+	.set		noreorder
+
+.Lmemset_partial\@:
+	R10KCBARRIER(0(ra))
+	PTR_LA		t1, 2f			/* where to start */
+#ifdef CONFIG_CPU_MICROMIPS
+	LONG_SRL	t7, t0, 1
+#endif
+#if LONGSIZE == 4
+	PTR_SUBU	t1, FILLPTRG
+#else
+	.set		noat
+	LONG_SRL	AT, FILLPTRG, 1
+	PTR_SUBU	t1, AT
+	.set		at
+#endif
+	jr		t1
+	 PTR_ADDU	a0, t0			/* dest ptr */
+
+	.set		push
+	.set		noreorder
+	.set		nomacro
+	/* ... but first do longs ... */
+	f_fill64 a0, -64, FILL64RG, .Lpartial_fixup\@, \mode
+2:	.set		pop
+	andi		a2, STORMASK		/* At most one long to go */
+
+	beqz		a2, 1f
+#ifndef CONFIG_CPU_MIPSR6
+	 PTR_ADDU	a0, a2			/* What's left */
+	R10KCBARRIER(0(ra))
+#ifdef __MIPSEB__
+	EX(LONG_S_R, a1, -1(a0), .Llast_fixup\@)
+#else
+	EX(LONG_S_L, a1, -1(a0), .Llast_fixup\@)
+#endif
+#else
+	 PTR_SUBU	t0, $0, a2
+	move		a2, zero		/* No remaining longs */
+	PTR_ADDIU	t0, 1
+	STORE_BYTE(0)
+	STORE_BYTE(1)
+#if LONGSIZE == 4
+	EX(sb, a1, 2(a0), .Lbyte_fixup\@)
+#else
+	STORE_BYTE(2)
+	STORE_BYTE(3)
+	STORE_BYTE(4)
+	STORE_BYTE(5)
+	EX(sb, a1, 6(a0), .Lbyte_fixup\@)
+#endif
+0:
+#endif
+1:	jr		ra
+	 move		a2, zero
+
+.Lsmall_memset\@:
+	beqz		a2, 2f
+	 PTR_ADDU	t1, a0, a2
+
+1:	PTR_ADDIU	a0, 1			/* fill bytewise */
+	R10KCBARRIER(0(ra))
+	bne		t1, a0, 1b
+	 EX(sb, a1, -1(a0), .Lsmall_fixup\@)
+
+2:	jr		ra			/* done */
+	 move		a2, zero
+	.if __memset == 1
+	END(memset)
+	.set __memset, 0
+	.hidden __memset
+	.endif
+
+#ifdef CONFIG_CPU_MIPSR6
+.Lbyte_fixup\@:
+	/*
+	 * unset_bytes = (#bytes - (#unaligned bytes)) - (-#unaligned bytes remaining + 1) + 1
+	 *      a2     =             a2                -              t0                   + 1
+	 */
+	PTR_SUBU	a2, t0
+	jr		ra
+	 PTR_ADDIU	a2, 1
+#endif /* CONFIG_CPU_MIPSR6 */
+
+.Lfirst_fixup\@:
+	/* unset_bytes already in a2 */
+	jr	ra
+	 nop
+
+.Lfwd_fixup\@:
+	/*
+	 * unset_bytes = partial_start_addr +  #bytes   -     fault_addr
+	 *      a2     =         t1         + (a2 & 3f) - $28->task->BUADDR
+	 */
+	PTR_L		t0, TI_TASK($28)
+	andi		a2, 0x3f
+	LONG_L		t0, THREAD_BUADDR(t0)
+	LONG_ADDU	a2, t1
+	jr		ra
+	 LONG_SUBU	a2, t0
+
+.Lpartial_fixup\@:
+	/*
+	 * unset_bytes = partial_end_addr +      #bytes     -     fault_addr
+	 *      a2     =       a0         + (a2 & STORMASK) - $28->task->BUADDR
+	 */
+	PTR_L		t0, TI_TASK($28)
+	andi		a2, STORMASK
+	LONG_L		t0, THREAD_BUADDR(t0)
+	LONG_ADDU	a2, a0
+	jr		ra
+	 LONG_SUBU	a2, t0
+
+.Llast_fixup\@:
+	/* unset_bytes already in a2 */
+	jr		ra
+	 nop
+
+.Lsmall_fixup\@:
+	/*
+	 * unset_bytes = end_addr - current_addr + 1
+	 *      a2     =    t1    -      a0      + 1
+	 */
+	.set		reorder
+	PTR_SUBU	a2, t1, a0
+	PTR_ADDIU	a2, 1
+	jr		ra
+	.set		noreorder
+
+	.endm
+
+/*
+ * memset(void *s, int c, size_t n)
+ *
+ * a0: start of area to clear
+ * a1: char to fill with
+ * a2: size of area to clear
+ */
+
+LEAF(memset)
+EXPORT_SYMBOL(memset)
+	beqz		a1, 1f
+	 move		v0, a0			/* result */
+
+	andi		a1, 0xff		/* spread fillword */
+	LONG_SLL		t1, a1, 8
+	or		a1, t1
+	LONG_SLL		t1, a1, 16
+#if LONGSIZE == 8
+	or		a1, t1
+	LONG_SLL		t1, a1, 32
+#endif
+	or		a1, t1
+1:
+#ifndef CONFIG_EVA
+FEXPORT(__bzero)
+EXPORT_SYMBOL(__bzero)
+#else
+FEXPORT(__bzero_kernel)
+EXPORT_SYMBOL(__bzero_kernel)
+#endif
+	__BUILD_BZERO LEGACY_MODE
+
+#ifdef CONFIG_EVA
+LEAF(__bzero)
+EXPORT_SYMBOL(__bzero)
+	__BUILD_BZERO EVA_MODE
+END(__bzero)
+#endif