1 files changed, 206 insertions, 0 deletions
diff --git a/sw/test-sha256/test-adder.c b/sw/test-sha256/test-adder.c
new file mode 100644
index 0000000..70415d8
--- /dev/null
+++ b/sw/test-sha256/test-adder.c
@@ -0,0 +1,206 @@
+//------------------------------------------------------------------------------
+// setup-eim.c
+//------------------------------------------------------------------------------
+
+
+//------------------------------------------------------------------------------
+// Headers
+//------------------------------------------------------------------------------
+#include <stdio.h>
+#include <stdlib.h>
+#include "novena-eim.h"
+
+
+//------------------------------------------------------------------------------
+// Demo Adder
+//------------------------------------------------------------------------------
+#define DEMO_ADDER_BASE_ADDR	(0x3210)
+#define DEMO_ADDER_REG_X		(EIM_BASE_ADDR + DEMO_ADDER_BASE_ADDR + (0<<2))
+#define DEMO_ADDER_REG_Y		(EIM_BASE_ADDR + DEMO_ADDER_BASE_ADDR + (1<<2))
+#define DEMO_ADDER_REG_Z		(EIM_BASE_ADDR + DEMO_ADDER_BASE_ADDR + (2<<2))
+#define DEMO_ADDER_REG_SC		(EIM_BASE_ADDR + DEMO_ADDER_BASE_ADDR + (3<<2))
+
+
+//------------------------------------------------------------------------------
+// Prototypes
+//------------------------------------------------------------------------------
+unsigned int	demo_adder_test_round	(unsigned int, unsigned int);
+unsigned int	lfsr_next_x				(unsigned int);
+unsigned int	lfsr_next_y				(unsigned int);
+
+
+//------------------------------------------------------------------------------
+// Testing Parameters
+//------------------------------------------------------------------------------
+const int	NUM_TEST_ROUNDS		= 10000;
+const int	PRINT_XYZ_VALUES	= 1;
+
+
+//------------------------------------------------------------------------------
+int main()
+//------------------------------------------------------------------------------
+{
+		// try to setup eim (return value should be 1)
+	printf("Configuring EIM .. ");
+	int ok = eim_setup();
+	if (ok < 1)
+	{	printf("ERROR\n");
+		return EXIT_FAILURE;
+	}
+	else printf("OK\n");
+	
+		// run test
+	int i;
+	unsigned int x = 0x12341234, y = 0xABCDABCD, zyx;
+	printf("Testing started.\n");
+	for (i=0; i<NUM_TEST_ROUNDS; i++)
+	{	
+			// run another round
+		unsigned int z = demo_adder_test_round(x, y);
+		
+			// calculate correct answer
+		zyx = x + y;
+
+			// check result
+		if (z != zyx)
+		{	printf("ERROR: round %10d of %10d: x == 0x%08X, y == 0x%08X, z == 0x%08X [z should be 0x%08X]\n", i+1, NUM_TEST_ROUNDS, x, y, z, zyx);
+			exit(EXIT_FAILURE);
+		}
+		else if (PRINT_XYZ_VALUES) printf("OK: round %10d of %10d: x == 0x%08X, y == 0x%08X, z == 0x%08X\n", i+1, NUM_TEST_ROUNDS, x, y, z);
+		
+			// update input values
+		x = lfsr_next_x(x);
+		y = lfsr_next_x(y);
+	}
+	
+		// ok
+	printf("Testing completed successfully.\n");
+	
+		// done
+	return EXIT_SUCCESS;
+}
+
+
+//------------------------------------------------------------------------------
+unsigned int demo_adder_test_round(unsigned int x, unsigned int y)
+//------------------------------------------------------------------------------
+{
+		// write x
+	eim_write_32(DEMO_ADDER_REG_X, &x);
+	
+		// write y
+	eim_write_32(DEMO_ADDER_REG_Y, &y);
+	
+		/* To make adder calculate something we need to change its control register,
+		 * so we read it, increment and write back. Control register is in the lower 16 bits.
+		 */
+	unsigned int ctl;
+	eim_read_32(DEMO_ADDER_REG_SC, &ctl);
+	ctl += 1;
+	ctl &= 0x0000FFFF;
+	eim_write_32(DEMO_ADDER_REG_SC, &ctl);
+	
+		/* When adder is done, it will write new control value into its status register. Adder has 1-cycle latency
+		 * which is very small, we don't even need to poll, just check that status was updated. Status register is
+		 * in the upper 16 bits.
+		 */
+	unsigned int sts;
+	eim_read_32(DEMO_ADDER_REG_SC, &sts);
+	sts >>= 16;
+	if (sts != ctl)
+	{	printf("ERROR: Adder timeout!\n");
+		exit(EXIT_FAILURE);
+	}
+
+		// read z
+	unsigned int z;
+	eim_read_32(DEMO_ADDER_REG_Z, &z);
+	
+		// uncomment to trigger an error
+	/**
+	z++;
+	**/
+	
+		// done
+	return z;
+}
+
+
+//------------------------------------------------------------------------------
+unsigned int lfsr_next_x(unsigned int value)
+//------------------------------------------------------------------------------
+{
+	//
+	// [32, 31, 29, 28, 27, 25, 24, 23, 21, 19, 17, 14, 10, 6, 4, 2]
+	//   0   1   3   4   5   7   8   9  11  13  15  18  22 24 28 30
+	//
+	
+	unsigned int carry = 0;
+
+	carry ^= (value >>  0);
+	carry ^= (value >>  1);
+	carry ^= (value >>  3);
+	carry ^= (value >>  4);
+
+	carry ^= (value >>  5);
+	carry ^= (value >>  7);
+	carry ^= (value >>  8);
+	carry ^= (value >>  9);
+
+	carry ^= (value >> 11);
+	carry ^= (value >> 13);
+	carry ^= (value >> 15);
+	carry ^= (value >> 18);
+
+	carry ^= (value >> 22);
+	carry ^= (value >> 24);
+	carry ^= (value >> 28);
+	carry ^= (value >> 30);
+
+	value >>= 1, value |= (carry << 31);
+
+	return value;
+}
+
+
+//------------------------------------------------------------------------------
+unsigned int lfsr_next_y(unsigned int value)
+//------------------------------------------------------------------------------
+{
+	//
+	// [32, 17, 16, 15, 14, 13, 12, 11, 10, 9, 8, 7, 6, 5, 4, 1]
+	//   0  15  16  17  18  19  20  21  22 23 24 25 26 27 28 31
+	//
+	
+	unsigned int carry = 0;
+
+	carry ^= (value >>  0);
+	carry ^= (value >> 15);
+	carry ^= (value >> 16);
+	carry ^= (value >> 17);
+
+	carry ^= (value >> 18);
+	carry ^= (value >> 19);
+	carry ^= (value >> 20);
+	carry ^= (value >> 21);
+
+	carry ^= (value >> 22);
+	carry ^= (value >> 23);
+	carry ^= (value >> 24);
+	carry ^= (value >> 25);
+
+	carry ^= (value >> 26);
+	carry ^= (value >> 27);
+	carry ^= (value >> 28);
+	carry ^= (value >> 31);
+
+	value >>= 1, value |= (carry << 31);
+
+	return value;
+}	
+
+
+
+//------------------------------------------------------------------------------
+// End-of-File
+//------------------------------------------------------------------------------