tests: add pld test

diff --git a/tests/test_pld.c b/tests/test_pld.c
new file mode 100644 (file)
index 0000000..8f2f89b
--- /dev/null
+++ b/tests/test_pld.c
@@ -0,0 +1,200 @@
+#include <stdio.h>
+#include <string.h>
+#include <sys/mman.h>
+
+#ifndef MAP_HUGETLB
+#define MAP_HUGETLB 0x40000 /* arch specific */
+#endif
+
+#define SIZE (10 * 1024 * 1024)
+
+static inline void pcnt_init(void)
+{
+       int v;
+       asm volatile("mrc p15, 0, %0, c9, c12, 0" : "=r"(v));
+       v |= 5; // master enable, ccnt reset
+       v &= ~8; // ccnt divider 0
+       asm volatile("mcr p15, 0, %0, c9, c12, 0" :: "r"(v));
+       // enable cycle counter
+       asm volatile("mcr p15, 0, %0, c9, c12, 1" :: "r"(1<<31));
+}
+
+static inline unsigned int pcnt_get(void)
+{
+       unsigned int val;
+       __asm__ volatile("mrc p15, 0, %0, c9, c13, 0"
+                        : "=r"(val));
+       return val;
+}
+
+extern void do_ldr64(void *mem, int bytes);
+extern void do_ldr64pld(void *mem, int bytes);
+extern void do_ldr32(void *mem, int bytes);
+extern void do_ldr32pld(void *mem, int bytes);
+extern void do_ldr4(void *mem, int bytes);
+extern void do_ldr4pld(void *mem, int bytes);
+extern void do_ldr4pld2(void *mem, int bytes);
+extern void do_ldr1(void *mem, int bytes);
+extern void do_ldr1pld(void *mem, int bytes);
+extern void do_ldr1ldr(void *mem, int bytes);
+extern void do_ldr1pld2(void *mem, int bytes);
+extern void do_pld64(void *mem, int bytes);
+asm(
+".align 3\n"
+"do_ldr64:\n"
+"  ldr  r3, [r0], #64\n"
+"  subs r1, #64\n"
+"  bgt  do_ldr64\n"
+"  nop\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr64pld:\n"
+"  ldr  r3, [r0], #64\n"
+"  subs r1, #64\n"
+"  pld  [r0, #64*3]\n"
+"  bgt  do_ldr64pld\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr32:\n"
+"  ldr  r3, [r0], #32\n"
+"  subs r1, #32\n"
+"  bgt  do_ldr32\n"
+"  nop\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr32pld:\n"
+"  ldr  r3, [r0], #32\n"
+"  subs r1, #32\n"
+"  pld  [r0, #64*3]\n"
+"  bgt  do_ldr32pld\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr4:\n"
+"  ldr  r3, [r0], #4\n"
+"  subs r1, #4\n"
+"  bgt  do_ldr4\n"
+"  nop\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr4pld:\n"
+"  ldr  r3, [r0], #4\n"
+"  subs r1, #4\n"
+"  pld  [r0, #64*2]\n"
+"  bgt  do_ldr4pld\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr4pld2:\n"
+"  ldr  r3, [r0]\n"
+"  sub  r1, #4\n"
+"  tst  r0, #63\n"
+"  bne  do_ldr4pld2\n"
+"  pld  [r0, #64*3]\n"
+"  tst  r1, r1\n"
+"  bne  do_ldr4pld2\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr1:\n"
+"  ldrb r3, [r0], #1\n"
+"  subs r1, #1\n"
+"  bgt  do_ldr1\n"
+"  nop\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr1pld:\n"
+"  ldrb r3, [r0], #1\n"
+"  subs r1, #1\n"
+"  pld  [r0, #64*2]\n"
+"  bgt  do_ldr1pld\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr1ldr:\n"
+"  sub  r1, #64*2+1\n"
+"  nop\n" // important!
+"0:\n"
+"  ldrb r3, [r0], #1\n"
+"  subs r1, #1\n"
+"  ldrb r12,[r0, #64*2]\n"
+"  bgt  0b\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_ldr1pld2:\n"
+"  ldrb r3, [r0], #1\n"
+"  sub  r1, #1\n"
+"  tst  r0, #63\n"
+"  bne  do_ldr1pld2\n"
+"  tst  r1, r1\n"
+"  pld  [r0, #64*2]\n"
+"  bne  do_ldr1pld2\n"
+"  bx   lr\n"
+
+".align 3\n"
+"do_pld64:\n"
+"  pld  [r0]\n"
+"  add  r0, #64\n"
+"  subs r1, #64\n"
+"  bgt  do_pld64\n"
+"  nop\n"
+"  bx   lr\n"
+);
+
+#define T(n) { #n, do_##n }
+static const struct {
+       const char *name;
+       void (*f)(void *mem, int bytes);
+} tests[] = {
+       T(ldr64),
+       T(ldr64pld),
+//     T(ldr32),
+//     T(ldr32pld),
+       T(ldr4),
+       T(ldr4pld),
+       T(ldr4pld2),
+       T(ldr1),
+       T(ldr1pld),
+       T(ldr1ldr),
+       T(ldr1pld2),
+       T(pld64),
+};
+
+int main()
+{
+       unsigned int cnt, min;
+       void *mem;
+       int t, i;
+
+       pcnt_init();
+
+       mem = mmap(NULL, SIZE, PROT_READ | PROT_WRITE,
+               MAP_PRIVATE | MAP_ANONYMOUS | MAP_HUGETLB | MAP_POPULATE, -1, 0);
+       if (mem == MAP_FAILED) {
+               perror("mmap");
+               return 1;
+       }
+       //memset(mem, 1, SIZE);
+
+       for (t = 0; t < sizeof(tests) / sizeof(tests[0]); t++) {
+               min = ~0;
+               for (i = 0; i < 8; i++) {
+                       cnt = pcnt_get();
+                       tests[t].f(mem, SIZE);
+                       cnt = pcnt_get() - cnt;
+                       if (min > cnt)
+                               min = cnt;
+               }
+               printf("%-8s %5.1f\n", tests[t].name, min / 1000000.0f);
+       }
+
+       munmap(mem, SIZE);
+
+       return 0;
+}