1 files changed, 70 insertions, 4 deletions

diff --git a/firmware/multest.c b/firmware/multest.c
index 93e48df..1706400 100644
--- a/firmware/multest.c
+++ b/firmware/multest.c
@@ -17,15 +17,35 @@ static uint32_t xorshift32(void) {
 
 void multest(void)
 {
-	for (int i = 0; i < 10; i++)
+	for (int i = 0; i < 15; i++)
 	{
 		uint32_t a = xorshift32();
 		uint32_t b = xorshift32();
 
+		switch (i)
+		{
+		case 0:
+			a = 0x80000000;
+			b = 0xFFFFFFFF;
+			break;
+		case 1:
+			a = 0;
+			b = 0;
+			break;
+		case 2:
+			a |= 0x80000000;
+			b = 0;
+			break;
+		case 3:
+			a &= 0x7FFFFFFF;
+			b = 0;
+			break;
+		}
+
 		uint64_t au = a, bu = b;
 		int64_t as = (int32_t)a, bs = (int32_t)b;
 
-		print_str("input [");
+		print_str("input     [");
 		print_hex(as >> 32, 8);
 		print_str("] ");
 		print_hex(a, 8);
@@ -36,7 +56,7 @@ void multest(void)
 		print_chr('\n');
 
 		uint32_t h_mul, h_mulh, h_mulhsu, h_mulhu;
-		print_str("hard   ");
+		print_str("hard mul   ");
 
 		h_mul = hard_mul(a, b);
 		print_hex(h_mul, 8);
@@ -55,7 +75,7 @@ void multest(void)
 		print_chr('\n');
 
 		uint32_t s_mul, s_mulh, s_mulhsu, s_mulhu;
-		print_str("soft   ");
+		print_str("soft mul   ");
 
 		s_mul = a * b;
 		print_hex(s_mul, 8);
@@ -80,6 +100,52 @@ void multest(void)
 		}
 
 		print_str(" OK\n");
+
+		uint32_t h_div, h_divu, h_rem, h_remu;
+		print_str("hard div   ");
+
+		h_div = hard_div(a, b);
+		print_hex(h_div, 8);
+		print_str("  ");
+
+		h_divu = hard_divu(a, b);
+		print_hex(h_divu, 8);
+		print_str("  ");
+
+		h_rem = hard_rem(a, b);
+		print_hex(h_rem, 8);
+		print_str("  ");
+
+		h_remu = hard_remu(a, b);
+		print_hex(h_remu, 8);
+		print_chr('\n');
+
+		uint32_t s_div, s_divu, s_rem, s_remu;
+		print_str("soft div   ");
+
+		s_div = b ? as / bs : 0xffffffff;
+		print_hex(s_div, 8);
+		print_str("  ");
+
+		s_divu = b ? au / bu : 0xffffffff;
+		print_hex(s_divu, 8);
+		print_str("  ");
+
+		s_rem = b ? as % bs : a;
+		print_hex(s_rem, 8);
+		print_str("  ");
+
+		s_remu = b ? au % bu : a;
+		print_hex(s_remu, 8);
+		print_str("  ");
+
+		if (s_div != h_div || s_divu != h_divu || s_rem != h_rem || s_remu != h_remu) {
+			print_str("ERROR!\n");
+			__asm__ volatile ("ebreak");
+			return;
+		}
+
+		print_str(" OK\n");
 	}
 }