Adding upstream version 4.19.249.upstream/4.19.249

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 642 insertions, 0 deletions

diff --git a/arch/powerpc/lib/memcmp_64.S b/arch/powerpc/lib/memcmp_64.S
new file mode 100644
index 000000000..b7f6f6e0b
--- /dev/null
+++ b/arch/powerpc/lib/memcmp_64.S
@@ -0,0 +1,642 @@
+/*
+ * Author: Anton Blanchard <anton@au.ibm.com>
+ * Copyright 2015 IBM Corporation.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+#include <asm/ppc_asm.h>
+#include <asm/export.h>
+#include <asm/ppc-opcode.h>
+
+#define off8	r6
+#define off16	r7
+#define off24	r8
+
+#define rA	r9
+#define rB	r10
+#define rC	r11
+#define rD	r27
+#define rE	r28
+#define rF	r29
+#define rG	r30
+#define rH	r31
+
+#ifdef __LITTLE_ENDIAN__
+#define LH	lhbrx
+#define LW	lwbrx
+#define LD	ldbrx
+#define LVS	lvsr
+#define VPERM(_VRT,_VRA,_VRB,_VRC) \
+	vperm _VRT,_VRB,_VRA,_VRC
+#else
+#define LH	lhzx
+#define LW	lwzx
+#define LD	ldx
+#define LVS	lvsl
+#define VPERM(_VRT,_VRA,_VRB,_VRC) \
+	vperm _VRT,_VRA,_VRB,_VRC
+#endif
+
+#define VMX_THRESH 4096
+#define ENTER_VMX_OPS	\
+	mflr    r0;	\
+	std     r3,-STACKFRAMESIZE+STK_REG(R31)(r1); \
+	std     r4,-STACKFRAMESIZE+STK_REG(R30)(r1); \
+	std     r5,-STACKFRAMESIZE+STK_REG(R29)(r1); \
+	std     r0,16(r1); \
+	stdu    r1,-STACKFRAMESIZE(r1); \
+	bl      enter_vmx_ops; \
+	cmpwi   cr1,r3,0; \
+	ld      r0,STACKFRAMESIZE+16(r1); \
+	ld      r3,STK_REG(R31)(r1); \
+	ld      r4,STK_REG(R30)(r1); \
+	ld      r5,STK_REG(R29)(r1); \
+	addi	r1,r1,STACKFRAMESIZE; \
+	mtlr    r0
+
+#define EXIT_VMX_OPS \
+	mflr    r0; \
+	std     r3,-STACKFRAMESIZE+STK_REG(R31)(r1); \
+	std     r4,-STACKFRAMESIZE+STK_REG(R30)(r1); \
+	std     r5,-STACKFRAMESIZE+STK_REG(R29)(r1); \
+	std     r0,16(r1); \
+	stdu    r1,-STACKFRAMESIZE(r1); \
+	bl      exit_vmx_ops; \
+	ld      r0,STACKFRAMESIZE+16(r1); \
+	ld      r3,STK_REG(R31)(r1); \
+	ld      r4,STK_REG(R30)(r1); \
+	ld      r5,STK_REG(R29)(r1); \
+	addi	r1,r1,STACKFRAMESIZE; \
+	mtlr    r0
+
+/*
+ * LD_VSR_CROSS16B load the 2nd 16 bytes for _vaddr which is unaligned with
+ * 16 bytes boundary and permute the result with the 1st 16 bytes.
+
+ *    |  y y y y y y y y y y y y y 0 1 2 | 3 4 5 6 7 8 9 a b c d e f z z z |
+ *    ^                                  ^                                 ^
+ * 0xbbbb10                          0xbbbb20                          0xbbb30
+ *                                 ^
+ *                                _vaddr
+ *
+ *
+ * _vmask is the mask generated by LVS
+ * _v1st_qw is the 1st aligned QW of current addr which is already loaded.
+ *   for example: 0xyyyyyyyyyyyyy012 for big endian
+ * _v2nd_qw is the 2nd aligned QW of cur _vaddr to be loaded.
+ *   for example: 0x3456789abcdefzzz for big endian
+ * The permute result is saved in _v_res.
+ *   for example: 0x0123456789abcdef for big endian.
+ */
+#define LD_VSR_CROSS16B(_vaddr,_vmask,_v1st_qw,_v2nd_qw,_v_res) \
+        lvx     _v2nd_qw,_vaddr,off16; \
+        VPERM(_v_res,_v1st_qw,_v2nd_qw,_vmask)
+
+/*
+ * There are 2 categories for memcmp:
+ * 1) src/dst has the same offset to the 8 bytes boundary. The handlers
+ * are named like .Lsameoffset_xxxx
+ * 2) src/dst has different offset to the 8 bytes boundary. The handlers
+ * are named like .Ldiffoffset_xxxx
+ */
+_GLOBAL_TOC(memcmp)
+	cmpdi	cr1,r5,0
+
+	/* Use the short loop if the src/dst addresses are not
+	 * with the same offset of 8 bytes align boundary.
+	 */
+	xor	r6,r3,r4
+	andi.	r6,r6,7
+
+	/* Fall back to short loop if compare at aligned addrs
+	 * with less than 8 bytes.
+	 */
+	cmpdi   cr6,r5,7
+
+	beq	cr1,.Lzero
+	bgt	cr6,.Lno_short
+
+.Lshort:
+	mtctr	r5
+1:	lbz	rA,0(r3)
+	lbz	rB,0(r4)
+	subf.	rC,rB,rA
+	bne	.Lnon_zero
+	bdz	.Lzero
+
+	lbz	rA,1(r3)
+	lbz	rB,1(r4)
+	subf.	rC,rB,rA
+	bne	.Lnon_zero
+	bdz	.Lzero
+
+	lbz	rA,2(r3)
+	lbz	rB,2(r4)
+	subf.	rC,rB,rA
+	bne	.Lnon_zero
+	bdz	.Lzero
+
+	lbz	rA,3(r3)
+	lbz	rB,3(r4)
+	subf.	rC,rB,rA
+	bne	.Lnon_zero
+
+	addi	r3,r3,4
+	addi	r4,r4,4
+
+	bdnz	1b
+
+.Lzero:
+	li	r3,0
+	blr
+
+.Lno_short:
+	dcbt	0,r3
+	dcbt	0,r4
+	bne	.Ldiffoffset_8bytes_make_align_start
+
+
+.Lsameoffset_8bytes_make_align_start:
+	/* attempt to compare bytes not aligned with 8 bytes so that
+	 * rest comparison can run based on 8 bytes alignment.
+	 */
+	andi.   r6,r3,7
+
+	/* Try to compare the first double word which is not 8 bytes aligned:
+	 * load the first double word at (src & ~7UL) and shift left appropriate
+	 * bits before comparision.
+	 */
+	rlwinm  r6,r3,3,26,28
+	beq     .Lsameoffset_8bytes_aligned
+	clrrdi	r3,r3,3
+	clrrdi	r4,r4,3
+	LD	rA,0,r3
+	LD	rB,0,r4
+	sld	rA,rA,r6
+	sld	rB,rB,r6
+	cmpld	cr0,rA,rB
+	srwi	r6,r6,3
+	bne	cr0,.LcmpAB_lightweight
+	subfic  r6,r6,8
+	subf.	r5,r6,r5
+	addi	r3,r3,8
+	addi	r4,r4,8
+	beq	.Lzero
+
+.Lsameoffset_8bytes_aligned:
+	/* now we are aligned with 8 bytes.
+	 * Use .Llong loop if left cmp bytes are equal or greater than 32B.
+	 */
+	cmpdi   cr6,r5,31
+	bgt	cr6,.Llong
+
+.Lcmp_lt32bytes:
+	/* compare 1 ~ 31 bytes, at least r3 addr is 8 bytes aligned now */
+	cmpdi   cr5,r5,7
+	srdi    r0,r5,3
+	ble	cr5,.Lcmp_rest_lt8bytes
+
+	/* handle 8 ~ 31 bytes */
+	clrldi  r5,r5,61
+	mtctr   r0
+2:
+	LD	rA,0,r3
+	LD	rB,0,r4
+	cmpld	cr0,rA,rB
+	addi	r3,r3,8
+	addi	r4,r4,8
+	bne	cr0,.LcmpAB_lightweight
+	bdnz	2b
+
+	cmpwi   r5,0
+	beq	.Lzero
+
+.Lcmp_rest_lt8bytes:
+	/*
+	 * Here we have less than 8 bytes to compare. At least s1 is aligned to
+	 * 8 bytes, but s2 may not be. We must make sure s2 + 7 doesn't cross a
+	 * page boundary, otherwise we might read past the end of the buffer and
+	 * trigger a page fault. We use 4K as the conservative minimum page
+	 * size. If we detect that case we go to the byte-by-byte loop.
+	 *
+	 * Otherwise the next double word is loaded from s1 and s2, and shifted
+	 * right to compare the appropriate bits.
+	 */
+	clrldi	r6,r4,(64-12)	// r6 = r4 & 0xfff
+	cmpdi	r6,0xff8
+	bgt	.Lshort
+
+	subfic  r6,r5,8
+	slwi	r6,r6,3
+	LD	rA,0,r3
+	LD	rB,0,r4
+	srd	rA,rA,r6
+	srd	rB,rB,r6
+	cmpld	cr0,rA,rB
+	bne	cr0,.LcmpAB_lightweight
+	b	.Lzero
+
+.Lnon_zero:
+	mr	r3,rC
+	blr
+
+.Llong:
+#ifdef CONFIG_ALTIVEC
+BEGIN_FTR_SECTION
+	/* Try to use vmx loop if length is equal or greater than 4K */
+	cmpldi  cr6,r5,VMX_THRESH
+	bge	cr6,.Lsameoffset_vmx_cmp
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+
+.Llong_novmx_cmp:
+#endif
+	/* At least s1 addr is aligned with 8 bytes */
+	li	off8,8
+	li	off16,16
+	li	off24,24
+
+	std	r31,-8(r1)
+	std	r30,-16(r1)
+	std	r29,-24(r1)
+	std	r28,-32(r1)
+	std	r27,-40(r1)
+
+	srdi	r0,r5,5
+	mtctr	r0
+	andi.	r5,r5,31
+
+	LD	rA,0,r3
+	LD	rB,0,r4
+
+	LD	rC,off8,r3
+	LD	rD,off8,r4
+
+	LD	rE,off16,r3
+	LD	rF,off16,r4
+
+	LD	rG,off24,r3
+	LD	rH,off24,r4
+	cmpld	cr0,rA,rB
+
+	addi	r3,r3,32
+	addi	r4,r4,32
+
+	bdz	.Lfirst32
+
+	LD	rA,0,r3
+	LD	rB,0,r4
+	cmpld	cr1,rC,rD
+
+	LD	rC,off8,r3
+	LD	rD,off8,r4
+	cmpld	cr6,rE,rF
+
+	LD	rE,off16,r3
+	LD	rF,off16,r4
+	cmpld	cr7,rG,rH
+	bne	cr0,.LcmpAB
+
+	LD	rG,off24,r3
+	LD	rH,off24,r4
+	cmpld	cr0,rA,rB
+	bne	cr1,.LcmpCD
+
+	addi	r3,r3,32
+	addi	r4,r4,32
+
+	bdz	.Lsecond32
+
+	.balign	16
+
+1:	LD	rA,0,r3
+	LD	rB,0,r4
+	cmpld	cr1,rC,rD
+	bne	cr6,.LcmpEF
+
+	LD	rC,off8,r3
+	LD	rD,off8,r4
+	cmpld	cr6,rE,rF
+	bne	cr7,.LcmpGH
+
+	LD	rE,off16,r3
+	LD	rF,off16,r4
+	cmpld	cr7,rG,rH
+	bne	cr0,.LcmpAB
+
+	LD	rG,off24,r3
+	LD	rH,off24,r4
+	cmpld	cr0,rA,rB
+	bne	cr1,.LcmpCD
+
+	addi	r3,r3,32
+	addi	r4,r4,32
+
+	bdnz	1b
+
+.Lsecond32:
+	cmpld	cr1,rC,rD
+	bne	cr6,.LcmpEF
+
+	cmpld	cr6,rE,rF
+	bne	cr7,.LcmpGH
+
+	cmpld	cr7,rG,rH
+	bne	cr0,.LcmpAB
+
+	bne	cr1,.LcmpCD
+	bne	cr6,.LcmpEF
+	bne	cr7,.LcmpGH
+
+.Ltail:
+	ld	r31,-8(r1)
+	ld	r30,-16(r1)
+	ld	r29,-24(r1)
+	ld	r28,-32(r1)
+	ld	r27,-40(r1)
+
+	cmpdi	r5,0
+	beq	.Lzero
+	b	.Lshort
+
+.Lfirst32:
+	cmpld	cr1,rC,rD
+	cmpld	cr6,rE,rF
+	cmpld	cr7,rG,rH
+
+	bne	cr0,.LcmpAB
+	bne	cr1,.LcmpCD
+	bne	cr6,.LcmpEF
+	bne	cr7,.LcmpGH
+
+	b	.Ltail
+
+.LcmpAB:
+	li	r3,1
+	bgt	cr0,.Lout
+	li	r3,-1
+	b	.Lout
+
+.LcmpCD:
+	li	r3,1
+	bgt	cr1,.Lout
+	li	r3,-1
+	b	.Lout
+
+.LcmpEF:
+	li	r3,1
+	bgt	cr6,.Lout
+	li	r3,-1
+	b	.Lout
+
+.LcmpGH:
+	li	r3,1
+	bgt	cr7,.Lout
+	li	r3,-1
+
+.Lout:
+	ld	r31,-8(r1)
+	ld	r30,-16(r1)
+	ld	r29,-24(r1)
+	ld	r28,-32(r1)
+	ld	r27,-40(r1)
+	blr
+
+.LcmpAB_lightweight:   /* skip NV GPRS restore */
+	li	r3,1
+	bgtlr
+	li	r3,-1
+	blr
+
+#ifdef CONFIG_ALTIVEC
+.Lsameoffset_vmx_cmp:
+	/* Enter with src/dst addrs has the same offset with 8 bytes
+	 * align boundary.
+	 *
+	 * There is an optimization based on following fact: memcmp()
+	 * prones to fail early at the first 32 bytes.
+	 * Before applying VMX instructions which will lead to 32x128bits
+	 * VMX regs load/restore penalty, we compare the first 32 bytes
+	 * so that we can catch the ~80% fail cases.
+	 */
+
+	li	r0,4
+	mtctr	r0
+.Lsameoffset_prechk_32B_loop:
+	LD	rA,0,r3
+	LD	rB,0,r4
+	cmpld	cr0,rA,rB
+	addi	r3,r3,8
+	addi	r4,r4,8
+	bne     cr0,.LcmpAB_lightweight
+	addi	r5,r5,-8
+	bdnz	.Lsameoffset_prechk_32B_loop
+
+	ENTER_VMX_OPS
+	beq     cr1,.Llong_novmx_cmp
+
+3:
+	/* need to check whether r4 has the same offset with r3
+	 * for 16 bytes boundary.
+	 */
+	xor	r0,r3,r4
+	andi.	r0,r0,0xf
+	bne	.Ldiffoffset_vmx_cmp_start
+
+	/* len is no less than 4KB. Need to align with 16 bytes further.
+	 */
+	andi.	rA,r3,8
+	LD	rA,0,r3
+	beq	4f
+	LD	rB,0,r4
+	cmpld	cr0,rA,rB
+	addi	r3,r3,8
+	addi	r4,r4,8
+	addi	r5,r5,-8
+
+	beq	cr0,4f
+	/* save and restore cr0 */
+	mfocrf  r5,128
+	EXIT_VMX_OPS
+	mtocrf  128,r5
+	b	.LcmpAB_lightweight
+
+4:
+	/* compare 32 bytes for each loop */
+	srdi	r0,r5,5
+	mtctr	r0
+	clrldi  r5,r5,59
+	li	off16,16
+
+.balign 16
+5:
+	lvx 	v0,0,r3
+	lvx 	v1,0,r4
+	VCMPEQUD_RC(v0,v0,v1)
+	bnl	cr6,7f
+	lvx 	v0,off16,r3
+	lvx 	v1,off16,r4
+	VCMPEQUD_RC(v0,v0,v1)
+	bnl	cr6,6f
+	addi	r3,r3,32
+	addi	r4,r4,32
+	bdnz	5b
+
+	EXIT_VMX_OPS
+	cmpdi	r5,0
+	beq	.Lzero
+	b	.Lcmp_lt32bytes
+
+6:
+	addi	r3,r3,16
+	addi	r4,r4,16
+
+7:
+	/* diff the last 16 bytes */
+	EXIT_VMX_OPS
+	LD	rA,0,r3
+	LD	rB,0,r4
+	cmpld	cr0,rA,rB
+	li	off8,8
+	bne	cr0,.LcmpAB_lightweight
+
+	LD	rA,off8,r3
+	LD	rB,off8,r4
+	cmpld	cr0,rA,rB
+	bne	cr0,.LcmpAB_lightweight
+	b	.Lzero
+#endif
+
+.Ldiffoffset_8bytes_make_align_start:
+	/* now try to align s1 with 8 bytes */
+	rlwinm  r6,r3,3,26,28
+	beq     .Ldiffoffset_align_s1_8bytes
+
+	clrrdi	r3,r3,3
+	LD	rA,0,r3
+	LD	rB,0,r4  /* unaligned load */
+	sld	rA,rA,r6
+	srd	rA,rA,r6
+	srd	rB,rB,r6
+	cmpld	cr0,rA,rB
+	srwi	r6,r6,3
+	bne	cr0,.LcmpAB_lightweight
+
+	subfic  r6,r6,8
+	subf.	r5,r6,r5
+	addi	r3,r3,8
+	add	r4,r4,r6
+
+	beq	.Lzero
+
+.Ldiffoffset_align_s1_8bytes:
+	/* now s1 is aligned with 8 bytes. */
+#ifdef CONFIG_ALTIVEC
+BEGIN_FTR_SECTION
+	/* only do vmx ops when the size equal or greater than 4K bytes */
+	cmpdi	cr5,r5,VMX_THRESH
+	bge	cr5,.Ldiffoffset_vmx_cmp
+END_FTR_SECTION_IFSET(CPU_FTR_ARCH_207S)
+
+.Ldiffoffset_novmx_cmp:
+#endif
+
+
+	cmpdi   cr5,r5,31
+	ble	cr5,.Lcmp_lt32bytes
+
+#ifdef CONFIG_ALTIVEC
+	b	.Llong_novmx_cmp
+#else
+	b	.Llong
+#endif
+
+#ifdef CONFIG_ALTIVEC
+.Ldiffoffset_vmx_cmp:
+	/* perform a 32 bytes pre-checking before
+	 * enable VMX operations.
+	 */
+	li	r0,4
+	mtctr	r0
+.Ldiffoffset_prechk_32B_loop:
+	LD	rA,0,r3
+	LD	rB,0,r4
+	cmpld	cr0,rA,rB
+	addi	r3,r3,8
+	addi	r4,r4,8
+	bne     cr0,.LcmpAB_lightweight
+	addi	r5,r5,-8
+	bdnz	.Ldiffoffset_prechk_32B_loop
+
+	ENTER_VMX_OPS
+	beq     cr1,.Ldiffoffset_novmx_cmp
+
+.Ldiffoffset_vmx_cmp_start:
+	/* Firstly try to align r3 with 16 bytes */
+	andi.   r6,r3,0xf
+	li	off16,16
+	beq     .Ldiffoffset_vmx_s1_16bytes_align
+
+	LVS	v3,0,r3
+	LVS	v4,0,r4
+
+	lvx     v5,0,r3
+	lvx     v6,0,r4
+	LD_VSR_CROSS16B(r3,v3,v5,v7,v9)
+	LD_VSR_CROSS16B(r4,v4,v6,v8,v10)
+
+	VCMPEQUB_RC(v7,v9,v10)
+	bnl	cr6,.Ldiffoffset_vmx_diff_found
+
+	subfic  r6,r6,16
+	subf    r5,r6,r5
+	add     r3,r3,r6
+	add     r4,r4,r6
+
+.Ldiffoffset_vmx_s1_16bytes_align:
+	/* now s1 is aligned with 16 bytes */
+	lvx     v6,0,r4
+	LVS	v4,0,r4
+	srdi	r6,r5,5  /* loop for 32 bytes each */
+	clrldi  r5,r5,59
+	mtctr	r6
+
+.balign	16
+.Ldiffoffset_vmx_32bytesloop:
+	/* the first qw of r4 was saved in v6 */
+	lvx	v9,0,r3
+	LD_VSR_CROSS16B(r4,v4,v6,v8,v10)
+	VCMPEQUB_RC(v7,v9,v10)
+	vor	v6,v8,v8
+	bnl	cr6,.Ldiffoffset_vmx_diff_found
+
+	addi	r3,r3,16
+	addi	r4,r4,16
+
+	lvx	v9,0,r3
+	LD_VSR_CROSS16B(r4,v4,v6,v8,v10)
+	VCMPEQUB_RC(v7,v9,v10)
+	vor	v6,v8,v8
+	bnl	cr6,.Ldiffoffset_vmx_diff_found
+
+	addi	r3,r3,16
+	addi	r4,r4,16
+
+	bdnz	.Ldiffoffset_vmx_32bytesloop
+
+	EXIT_VMX_OPS
+
+	cmpdi	r5,0
+	beq	.Lzero
+	b	.Lcmp_lt32bytes
+
+.Ldiffoffset_vmx_diff_found:
+	EXIT_VMX_OPS
+	/* anyway, the diff will appear in next 16 bytes */
+	li	r5,16
+	b	.Lcmp_lt32bytes
+
+#endif
+EXPORT_SYMBOL(memcmp)