text: /*
   * Test the powerpc alignment handler on POWER8/POWER9
   *
   * Copyright (C) 2017 IBM Corporation (Michael Neuling, Andrew Donnellan)
   *
   * 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.
   */
  
  /*
   * This selftest exercises the powerpc alignment fault handler.
   *
   * We create two sets of source and destination buffers, one in regular memory,
   * the other cache-inhibited (we use /dev/fb0 for this).
   *
   * We initialise the source buffers, then use whichever set of load/store
   * instructions is under test to copy bytes from the source buffers to the
   * destination buffers. For the regular buffers, these instructions will
   * execute normally. For the cache-inhibited buffers, these instructions
   * will trap and cause an alignment fault, and the alignment fault handler
   * will emulate the particular instruction under test. We then compare the
   * destination buffers to ensure that the native and emulated cases give the
   * same result.
   *
   * TODO:
   *   - Any FIXMEs below
   *   - Test VSX regs < 32 and > 32
   *   - Test all loads and stores
   *   - Check update forms do update register
   *   - Test alignment faults over page boundary
   *
   * Some old binutils may not support all the instructions.
   */
  
  
  #include <sys/mman.h>
  #include <sys/types.h>
  #include <sys/stat.h>
  #include <fcntl.h>
  #include <unistd.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <assert.h>
  #include <getopt.h>
  #include <setjmp.h>
  #include <signal.h>
  
  #include "utils.h"
  
  int bufsize;
  int debug;
  int testing;
  volatile int gotsig;
  
  void sighandler(int sig, siginfo_t *info, void *ctx)
  {
  	ucontext_t *ucp = ctx;
  
  	if (!testing) {
  		signal(sig, SIG_DFL);
  		kill(0, sig);
  	}
  	gotsig = sig;
  #ifdef __powerpc64__
  	ucp->uc_mcontext.gp_regs[PT_NIP] += 4;
  #else
  	ucp->uc_mcontext.uc_regs->gregs[PT_NIP] += 4;
  #endif
  }
  
  #define XFORM(reg, n)  " " #reg " ,%"#n",%2 ;"
  #define DFORM(reg, n)  " " #reg " ,0(%"#n") ;"
  
  #define TEST(name, ld_op, st_op, form, ld_reg, st_reg)		\
  	void test_##name(char *s, char *d)			\
  	{							\
  		asm volatile(					\
  			#ld_op form(ld_reg, 0)			\
  			#st_op form(st_reg, 1)			\
  			:: "r"(s), "r"(d), "r"(0)		\
  			: "memory", "vs0", "vs32", "r31");	\
  	}							\
  	rc |= do_test(#name, test_##name)
  
  #define LOAD_VSX_XFORM_TEST(op) TEST(op, op, stxvd2x, XFORM, 32, 32)
  #define STORE_VSX_XFORM_TEST(op) TEST(op, lxvd2x, op, XFORM, 32, 32)
  #define LOAD_VSX_DFORM_TEST(op) TEST(op, op, stxv, DFORM, 32, 32)
  #define STORE_VSX_DFORM_TEST(op) TEST(op, lxv, op, DFORM, 32, 32)
  #define LOAD_VMX_XFORM_TEST(op) TEST(op, op, stxvd2x, XFORM, 0, 32)
  #define STORE_VMX_XFORM_TEST(op) TEST(op, lxvd2x, op, XFORM, 32, 0)
  #define LOAD_VMX_DFORM_TEST(op) TEST(op, op, stxv, DFORM, 0, 32)
  #define STORE_VMX_DFORM_TEST(op) TEST(op, lxv, op, DFORM, 32, 0)
  
  #define LOAD_XFORM_TEST(op) TEST(op, op, stdx, XFORM, 31, 31)
  #define STORE_XFORM_TEST(op) TEST(op, ldx, op, XFORM, 31, 31)
  #define LOAD_DFORM_TEST(op) TEST(op, op, std, DFORM, 31, 31)
  #define STORE_DFORM_TEST(op) TEST(op, ld, op, DFORM, 31, 31)
  
  #define LOAD_FLOAT_DFORM_TEST(op)  TEST(op, op, stfd, DFORM, 0, 0)
  #define STORE_FLOAT_DFORM_TEST(op) TEST(op, lfd, op, DFORM, 0, 0)
  #define LOAD_FLOAT_XFORM_TEST(op)  TEST(op, op, stfdx, XFORM, 0, 0)
  #define STORE_FLOAT_XFORM_TEST(op) TEST(op, lfdx, op, XFORM, 0, 0)
  
  
  /* FIXME: Unimplemented tests: */
  // STORE_DFORM_TEST(stq)   /* FIXME: need two registers for quad */
  // STORE_DFORM_TEST(stswi) /* FIXME: string instruction */
  
  // STORE_XFORM_TEST(stwat) /* AMO can't emulate or run on CI */
  // STORE_XFORM_TEST(stdat) /* ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ */
  
  
  /* preload byte by byte */
  void preload_data(void *dst, int offset, int width)
  {
  	char *c = dst;
  	int i;
  
  	c += offset;
  
  	for (i = 0 ; i < width ; i++)
  		c[i] = i;
  }
  
  int test_memcpy(void *dst, void *src, int size, int offset,
  		void (*test_func)(char *, char *))
  {
  	char *s, *d;
  
  	s = src;
  	s += offset;
  	d = dst;
  	d += offset;
  
  	assert(size == 16);
  	gotsig = 0;
  	testing = 1;
  
  	test_func(s, d); /* run the actual test */
  
  	testing = 0;
  	if (gotsig) {
  		if (debug)
  			printf("  Got signal %i\n", gotsig);
  		return 1;
  	}
  	return 0;
  }
  
  void dumpdata(char *s1, char *s2, int n, char *test_name)
  {
  	int i;
  
  	printf("  %s: unexpected result:\n", test_name);
  	printf("    mem:");
  	for (i = 0; i < n; i++)
  		printf(" %02x", s1[i]);
  	printf("\n");
  	printf("    ci: ");
  	for (i = 0; i < n; i++)
  		printf(" %02x", s2[i]);
  	printf("\n");
  }
  
  int test_memcmp(void *s1, void *s2, int n, int offset, char *test_name)
  {
  	char *s1c, *s2c;
  
  	s1c = s1;
  	s1c += offset;
  	s2c = s2;
  	s2c += offset;
  
  	if (memcmp(s1c, s2c, n)) {
  		if (debug) {
  			printf("\n  Compare failed. Offset:%i length:%i\n",
  			       offset, n);
  			dumpdata(s1c, s2c, n, test_name);
  		}
  		return 1;
  	}
  	return 0;
  }
  
  /*
   * Do two memcpy tests using the same instructions. One cachable
   * memory and the other doesn't.
   */
  int do_test(char *test_name, void (*test_func)(char *, char *))
  {
  	int offset, width, fd, rc = 0, r;
  	void *mem0, *mem1, *ci0, *ci1;
  
  	printf("\tDoing %s:\t", test_name);
  
  	fd = open("/dev/fb0", O_RDWR);
  	if (fd < 0) {
  		printf("\n");
  		perror("Can't open /dev/fb0");
  		SKIP_IF(1);
  	}
  
  	ci0 = mmap(NULL, bufsize, PROT_WRITE, MAP_SHARED,
  		   fd, 0x0);
  	ci1 = mmap(NULL, bufsize, PROT_WRITE, MAP_SHARED,
  		   fd, bufsize);
  	if ((ci0 == MAP_FAILED) || (ci1 == MAP_FAILED)) {
  		printf("\n");
  		perror("mmap failed");
  		SKIP_IF(1);
  	}
  
  	rc = posix_memalign(&mem0, bufsize, bufsize);
  	if (rc) {
  		printf("\n");
  		return rc;
  	}
  
  	rc = posix_memalign(&mem1, bufsize, bufsize);
  	if (rc) {
  		printf("\n");
  		free(mem0);
  		return rc;
  	}
  
  	/* offset = 0 no alignment fault, so skip */
  	for (offset = 1; offset < 16; offset++) {
  		width = 16; /* vsx == 16 bytes */
  		r = 0;
  
  		/* load pattern into memory byte by byte */
  		preload_data(ci0, offset, width);
  		preload_data(mem0, offset, width); // FIXME: remove??
  		memcpy(ci0, mem0, bufsize);
  		memcpy(ci1, mem1, bufsize); /* initialise output to the same */
  
  		/* sanity check */
  		test_memcmp(mem0, ci0, width, offset, test_name);
  
  		r |= test_memcpy(ci1,  ci0,  width, offset, test_func);
  		r |= test_memcpy(mem1, mem0, width, offset, test_func);
  		if (r && !debug) {
  			printf("FAILED: Got signal");
  			break;
  		}
  
  		r |= test_memcmp(mem1, ci1, width, offset, test_name);
  		rc |= r;
  		if (r && !debug) {
  			printf("FAILED: Wrong Data");
  			break;
  		}
  	}
  	if (!r)
  		printf("PASSED");
  	printf("\n");
  
  	munmap(ci0, bufsize);
  	munmap(ci1, bufsize);
  	free(mem0);
  	free(mem1);
  
  	return rc;
  }
  
  int test_alignment_handler_vsx_206(void)
  {
  	int rc = 0;
  
  	printf("VSX: 2.06B\n");
  	LOAD_VSX_XFORM_TEST(lxvd2x);
  	LOAD_VSX_XFORM_TEST(lxvw4x);
  	LOAD_VSX_XFORM_TEST(lxsdx);
  	LOAD_VSX_XFORM_TEST(lxvdsx);
  	STORE_VSX_XFORM_TEST(stxvd2x);
  	STORE_VSX_XFORM_TEST(stxvw4x);
  	STORE_VSX_XFORM_TEST(stxsdx);
  	return rc;
  }
  
  int test_alignment_handler_vsx_207(void)
  {
  	int rc = 0;
  
  	printf("VSX: 2.07B\n");
  	LOAD_VSX_XFORM_TEST(lxsspx);
  	LOAD_VSX_XFORM_TEST(lxsiwax);
  	LOAD_VSX_XFORM_TEST(lxsiwzx);
  	STORE_VSX_XFORM_TEST(stxsspx);
  	STORE_VSX_XFORM_TEST(stxsiwx);
  	return rc;
  }
  
  int test_alignment_handler_vsx_300(void)
  {
  	int rc = 0;
  
  	SKIP_IF(!have_hwcap2(PPC_FEATURE2_ARCH_3_00));
  	printf("VSX: 3.00B\n");
  	LOAD_VMX_DFORM_TEST(lxsd);
  	LOAD_VSX_XFORM_TEST(lxsibzx);
  	LOAD_VSX_XFORM_TEST(lxsihzx);
  	LOAD_VMX_DFORM_TEST(lxssp);
  	LOAD_VSX_DFORM_TEST(lxv);
  	LOAD_VSX_XFORM_TEST(lxvb16x);
  	LOAD_VSX_XFORM_TEST(lxvh8x);
  	LOAD_VSX_XFORM_TEST(lxvx);
  	LOAD_VSX_XFORM_TEST(lxvwsx);
  	LOAD_VSX_XFORM_TEST(lxvl);
  	LOAD_VSX_XFORM_TEST(lxvll);
  	STORE_VMX_DFORM_TEST(stxsd);
  	STORE_VSX_XFORM_TEST(stxsibx);
  	STORE_VSX_XFORM_TEST(stxsihx);
  	STORE_VMX_DFORM_TEST(stxssp);
  	STORE_VSX_DFORM_TEST(stxv);
  	STORE_VSX_XFORM_TEST(stxvb16x);
  	STORE_VSX_XFORM_TEST(stxvh8x);
  	STORE_VSX_XFORM_TEST(stxvx);
  	STORE_VSX_XFORM_TEST(stxvl);
  	STORE_VSX_XFORM_TEST(stxvll);
  	return rc;
  }
  
  int test_alignment_handler_integer(void)
  {
  	int rc = 0;
  
  	printf("Integer\n");
  	LOAD_DFORM_TEST(lbz);
  	LOAD_DFORM_TEST(lbzu);
  	LOAD_XFORM_TEST(lbzx);
  	LOAD_XFORM_TEST(lbzux);
  	LOAD_DFORM_TEST(lhz);
  	LOAD_DFORM_TEST(lhzu);
  	LOAD_XFORM_TEST(lhzx);
  	LOAD_XFORM_TEST(lhzux);
  	LOAD_DFORM_TEST(lha);
  	LOAD_DFORM_TEST(lhau);
  	LOAD_XFORM_TEST(lhax);
  	LOAD_XFORM_TEST(lhaux);
  	LOAD_XFORM_TEST(lhbrx);
  	LOAD_DFORM_TEST(lwz);
  	LOAD_DFORM_TEST(lwzu);
  	LOAD_XFORM_TEST(lwzx);
  	LOAD_XFORM_TEST(lwzux);
  	LOAD_DFORM_TEST(lwa);
  	LOAD_XFORM_TEST(lwax);
  	LOAD_XFORM_TEST(lwaux);
  	LOAD_XFORM_TEST(lwbrx);
  	LOAD_DFORM_TEST(ld);
  	LOAD_DFORM_TEST(ldu);
  	LOAD_XFORM_TEST(ldx);
  	LOAD_XFORM_TEST(ldux);
  	LOAD_XFORM_TEST(ldbrx);
  	LOAD_DFORM_TEST(lmw);
  	STORE_DFORM_TEST(stb);
  	STORE_XFORM_TEST(stbx);
  	STORE_DFORM_TEST(stbu);
  	STORE_XFORM_TEST(stbux);
  	STORE_DFORM_TEST(sth);
  	STORE_XFORM_TEST(sthx);
  	STORE_DFORM_TEST(sthu);
  	STORE_XFORM_TEST(sthux);
  	STORE_XFORM_TEST(sthbrx);
  	STORE_DFORM_TEST(stw);
  	STORE_XFORM_TEST(stwx);
  	STORE_DFORM_TEST(stwu);
  	STORE_XFORM_TEST(stwux);
  	STORE_XFORM_TEST(stwbrx);
  	STORE_DFORM_TEST(std);
  	STORE_XFORM_TEST(stdx);
  	STORE_DFORM_TEST(stdu);
  	STORE_XFORM_TEST(stdux);
  	STORE_XFORM_TEST(stdbrx);
  	STORE_DFORM_TEST(stmw);
  	return rc;
  }
  
  int test_alignment_handler_vmx(void)
  {
  	int rc = 0;
  
  	printf("VMX\n");
  	LOAD_VMX_XFORM_TEST(lvx);
  
  	/*
  	 * FIXME: These loads only load part of the register, so our
  	 * testing method doesn't work. Also they don't take alignment
  	 * faults, so it's kinda pointless anyway
  	 *
  	 LOAD_VMX_XFORM_TEST(lvebx)
  	 LOAD_VMX_XFORM_TEST(lvehx)
  	 LOAD_VMX_XFORM_TEST(lvewx)
  	 LOAD_VMX_XFORM_TEST(lvxl)
  	*/
  	STORE_VMX_XFORM_TEST(stvx);
  	STORE_VMX_XFORM_TEST(stvebx);
  	STORE_VMX_XFORM_TEST(stvehx);
  	STORE_VMX_XFORM_TEST(stvewx);
  	STORE_VMX_XFORM_TEST(stvxl);
  	return rc;
  }
  
  int test_alignment_handler_fp(void)
  {
  	int rc = 0;
  
  	printf("Floating point\n");
  	LOAD_FLOAT_DFORM_TEST(lfd);
  	LOAD_FLOAT_XFORM_TEST(lfdx);
  	LOAD_FLOAT_DFORM_TEST(lfdp);
  	LOAD_FLOAT_XFORM_TEST(lfdpx);
  	LOAD_FLOAT_DFORM_TEST(lfdu);
  	LOAD_FLOAT_XFORM_TEST(lfdux);
  	LOAD_FLOAT_DFORM_TEST(lfs);
  	LOAD_FLOAT_XFORM_TEST(lfsx);
  	LOAD_FLOAT_DFORM_TEST(lfsu);
  	LOAD_FLOAT_XFORM_TEST(lfsux);
  	LOAD_FLOAT_XFORM_TEST(lfiwzx);
  	LOAD_FLOAT_XFORM_TEST(lfiwax);
  	STORE_FLOAT_DFORM_TEST(stfd);
  	STORE_FLOAT_XFORM_TEST(stfdx);
  	STORE_FLOAT_DFORM_TEST(stfdp);
  	STORE_FLOAT_XFORM_TEST(stfdpx);
  	STORE_FLOAT_DFORM_TEST(stfdu);
  	STORE_FLOAT_XFORM_TEST(stfdux);
  	STORE_FLOAT_DFORM_TEST(stfs);
  	STORE_FLOAT_XFORM_TEST(stfsx);
  	STORE_FLOAT_DFORM_TEST(stfsu);
  	STORE_FLOAT_XFORM_TEST(stfsux);
  	STORE_FLOAT_XFORM_TEST(stfiwx);
  
  	return rc;
  }
  
  void usage(char *prog)
  {
  	printf("Usage: %s [options]\n", prog);
  	printf("  -d	Enable debug error output\n");
  	printf("\n");
  	printf("This test requires a POWER8 or POWER9 CPU and a usable ");
  	printf("framebuffer at /dev/fb0.\n");
  }
  
  int main(int argc, char *argv[])
  {
  
  	struct sigaction sa;
  	int rc = 0;
  	int option = 0;
  
  	while ((option = getopt(argc, argv, "d")) != -1) {
  		switch (option) {
  		case 'd':
  			debug++;
  			break;
  		default:
  			usage(argv[0]);
  			exit(1);
  		}
  	}
  
  	bufsize = getpagesize();
  
  	sa.sa_sigaction = sighandler;
  	sigemptyset(&sa.sa_mask);
  	sa.sa_flags = SA_SIGINFO;
  	if (sigaction(SIGSEGV, &sa, NULL) == -1
  	    || sigaction(SIGBUS, &sa, NULL) == -1
  	    || sigaction(SIGILL, &sa, NULL) == -1) {
  		perror("sigaction");
  		exit(1);
  	}
  
  	rc |= test_harness(test_alignment_handler_vsx_206,
  			   "test_alignment_handler_vsx_206");
  	rc |= test_harness(test_alignment_handler_vsx_207,
  			   "test_alignment_handler_vsx_207");
  	rc |= test_harness(test_alignment_handler_vsx_300,
  			   "test_alignment_handler_vsx_300");
  	rc |= test_harness(test_alignment_handler_integer,
  			   "test_alignment_handler_integer");
  	rc |= test_harness(test_alignment_handler_vmx,
  			   "test_alignment_handler_vmx");
  	rc |= test_harness(test_alignment_handler_fp,
  			   "test_alignment_handler_fp");
  	return rc;
  }
  