text: /* SPDX-License-Identifier: GPL-2.0-only */
  /*
   *  arch/arm/include/asm/xor.h
   *
   *  Copyright (C) 2001 Russell King
   */
  #include <linux/hardirq.h>
  #include <asm-generic/xor.h>
  #include <asm/hwcap.h>
  #include <asm/neon.h>
  
  #define __XOR(a1, a2) a1 ^= a2
  
  #define GET_BLOCK_2(dst) \
  	__asm__("ldmia	%0, {%1, %2}" \
  		: "=r" (dst), "=r" (a1), "=r" (a2) \
  		: "0" (dst))
  
  #define GET_BLOCK_4(dst) \
  	__asm__("ldmia	%0, {%1, %2, %3, %4}" \
  		: "=r" (dst), "=r" (a1), "=r" (a2), "=r" (a3), "=r" (a4) \
  		: "0" (dst))
  
  #define XOR_BLOCK_2(src) \
  	__asm__("ldmia	%0!, {%1, %2}" \
  		: "=r" (src), "=r" (b1), "=r" (b2) \
  		: "0" (src)); \
  	__XOR(a1, b1); __XOR(a2, b2);
  
  #define XOR_BLOCK_4(src) \
  	__asm__("ldmia	%0!, {%1, %2, %3, %4}" \
  		: "=r" (src), "=r" (b1), "=r" (b2), "=r" (b3), "=r" (b4) \
  		: "0" (src)); \
  	__XOR(a1, b1); __XOR(a2, b2); __XOR(a3, b3); __XOR(a4, b4)
  
  #define PUT_BLOCK_2(dst) \
  	__asm__ __volatile__("stmia	%0!, {%2, %3}" \
  		: "=r" (dst) \
  		: "0" (dst), "r" (a1), "r" (a2))
  
  #define PUT_BLOCK_4(dst) \
  	__asm__ __volatile__("stmia	%0!, {%2, %3, %4, %5}" \
  		: "=r" (dst) \
  		: "0" (dst), "r" (a1), "r" (a2), "r" (a3), "r" (a4))
  
  static void
  xor_arm4regs_2(unsigned long bytes, unsigned long * __restrict p1,
  	       const unsigned long * __restrict p2)
  {
  	unsigned int lines = bytes / sizeof(unsigned long) / 4;
  	register unsigned int a1 __asm__("r4");
  	register unsigned int a2 __asm__("r5");
  	register unsigned int a3 __asm__("r6");
  	register unsigned int a4 __asm__("r7");
  	register unsigned int b1 __asm__("r8");
  	register unsigned int b2 __asm__("r9");
  	register unsigned int b3 __asm__("ip");
  	register unsigned int b4 __asm__("lr");
  
  	do {
  		GET_BLOCK_4(p1);
  		XOR_BLOCK_4(p2);
  		PUT_BLOCK_4(p1);
  	} while (--lines);
  }
  
  static void
  xor_arm4regs_3(unsigned long bytes, unsigned long * __restrict p1,
  	       const unsigned long * __restrict p2,
  	       const unsigned long * __restrict p3)
  {
  	unsigned int lines = bytes / sizeof(unsigned long) / 4;
  	register unsigned int a1 __asm__("r4");
  	register unsigned int a2 __asm__("r5");
  	register unsigned int a3 __asm__("r6");
  	register unsigned int a4 __asm__("r7");
  	register unsigned int b1 __asm__("r8");
  	register unsigned int b2 __asm__("r9");
  	register unsigned int b3 __asm__("ip");
  	register unsigned int b4 __asm__("lr");
  
  	do {
  		GET_BLOCK_4(p1);
  		XOR_BLOCK_4(p2);
  		XOR_BLOCK_4(p3);
  		PUT_BLOCK_4(p1);
  	} while (--lines);
  }
  
  static void
  xor_arm4regs_4(unsigned long bytes, unsigned long * __restrict p1,
  	       const unsigned long * __restrict p2,
  	       const unsigned long * __restrict p3,
  	       const unsigned long * __restrict p4)
  {
  	unsigned int lines = bytes / sizeof(unsigned long) / 2;
  	register unsigned int a1 __asm__("r8");
  	register unsigned int a2 __asm__("r9");
  	register unsigned int b1 __asm__("ip");
  	register unsigned int b2 __asm__("lr");
  
  	do {
  		GET_BLOCK_2(p1);
  		XOR_BLOCK_2(p2);
  		XOR_BLOCK_2(p3);
  		XOR_BLOCK_2(p4);
  		PUT_BLOCK_2(p1);
  	} while (--lines);
  }
  
  static void
  xor_arm4regs_5(unsigned long bytes, unsigned long * __restrict p1,
  	       const unsigned long * __restrict p2,
  	       const unsigned long * __restrict p3,
  	       const unsigned long * __restrict p4,
  	       const unsigned long * __restrict p5)
  {
  	unsigned int lines = bytes / sizeof(unsigned long) / 2;
  	register unsigned int a1 __asm__("r8");
  	register unsigned int a2 __asm__("r9");
  	register unsigned int b1 __asm__("ip");
  	register unsigned int b2 __asm__("lr");
  
  	do {
  		GET_BLOCK_2(p1);
  		XOR_BLOCK_2(p2);
  		XOR_BLOCK_2(p3);
  		XOR_BLOCK_2(p4);
  		XOR_BLOCK_2(p5);
  		PUT_BLOCK_2(p1);
  	} while (--lines);
  }
  
  static struct xor_block_template xor_block_arm4regs = {
  	.name	= "arm4regs",
  	.do_2	= xor_arm4regs_2,
  	.do_3	= xor_arm4regs_3,
  	.do_4	= xor_arm4regs_4,
  	.do_5	= xor_arm4regs_5,
  };
  
  #undef XOR_TRY_TEMPLATES
  #define XOR_TRY_TEMPLATES			\
  	do {					\
  		xor_speed(&xor_block_arm4regs);	\
  		xor_speed(&xor_block_8regs);	\
  		xor_speed(&xor_block_32regs);	\
  		NEON_TEMPLATES;			\
  	} while (0)
  
  #ifdef CONFIG_KERNEL_MODE_NEON
  
  extern struct xor_block_template const xor_block_neon_inner;
  
  static void
  xor_neon_2(unsigned long bytes, unsigned long * __restrict p1,
  	   const unsigned long * __restrict p2)
  {
  	if (in_interrupt()) {
  		xor_arm4regs_2(bytes, p1, p2);
  	} else {
  		kernel_neon_begin();
  		xor_block_neon_inner.do_2(bytes, p1, p2);
  		kernel_neon_end();
  	}
  }
  
  static void
  xor_neon_3(unsigned long bytes, unsigned long * __restrict p1,
  	   const unsigned long * __restrict p2,
  	   const unsigned long * __restrict p3)
  {
  	if (in_interrupt()) {
  		xor_arm4regs_3(bytes, p1, p2, p3);
  	} else {
  		kernel_neon_begin();
  		xor_block_neon_inner.do_3(bytes, p1, p2, p3);
  		kernel_neon_end();
  	}
  }
  
  static void
  xor_neon_4(unsigned long bytes, unsigned long * __restrict p1,
  	   const unsigned long * __restrict p2,
  	   const unsigned long * __restrict p3,
  	   const unsigned long * __restrict p4)
  {
  	if (in_interrupt()) {
  		xor_arm4regs_4(bytes, p1, p2, p3, p4);
  	} else {
  		kernel_neon_begin();
  		xor_block_neon_inner.do_4(bytes, p1, p2, p3, p4);
  		kernel_neon_end();
  	}
  }
  
  static void
  xor_neon_5(unsigned long bytes, unsigned long * __restrict p1,
  	   const unsigned long * __restrict p2,
  	   const unsigned long * __restrict p3,
  	   const unsigned long * __restrict p4,
  	   const unsigned long * __restrict p5)
  {
  	if (in_interrupt()) {
  		xor_arm4regs_5(bytes, p1, p2, p3, p4, p5);
  	} else {
  		kernel_neon_begin();
  		xor_block_neon_inner.do_5(bytes, p1, p2, p3, p4, p5);
  		kernel_neon_end();
  	}
  }
  
  static struct xor_block_template xor_block_neon = {
  	.name	= "neon",
  	.do_2	= xor_neon_2,
  	.do_3	= xor_neon_3,
  	.do_4	= xor_neon_4,
  	.do_5	= xor_neon_5
  };
  
  #define NEON_TEMPLATES	\
  	do { if (cpu_has_neon()) xor_speed(&xor_block_neon); } while (0)
  #else
  #define NEON_TEMPLATES
  #endif
  