Add program for writing to memory using axis port

The application takes one argument, the number (or length) of data to be
written to the memory.

The physical address in main memory that is going to be written to is the
address of the CMA memory region on my currently running system.

app/Makefile

@@ -4,6 +4,7 @@ CFLAGS := -c -Wall -Werror
 INCLUDES := -I.
 
 EXECUTABLE = \
+	write-memory \
 	read-memory \
 	test-cfg
 
@@ -16,6 +17,10 @@ all : $(EXECUTABLE)
 	$(CC) $(INCLUDES) $(CFLAGS) $< -o $@
 
 
+write-memory : write-memory.o
+	$(CC) $< -o $@ $(LDFLAGS)
+
+
 read-memory : read-memory.o
 	$(CC) $< -o $@ $(LDFLAGS)
 

app/write-memory.c

@@ -0,0 +1,82 @@
+#include <interface.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <fcntl.h>
+#include <sys/mman.h>
+
+enum cfg_regsiters {
+	CFG_AXIS_ADDR,
+	CFG_AXIS_DATA,
+	CFG_HP0_DST_CNT,
+	CFG_HP0_SRC_CNT,
+	CFG_HP0_DST_DATA,
+	CFG_HP0_SRC_DATA,
+	CFG_EMPTY,
+};
+
+int main(int argc, char *argv[])
+{
+	int i = 0;
+
+	if (axis_init("/dev/axis") != 0) {
+		return -1;
+	}
+
+	if (argc < 2) {
+		printf("Usage: %s <length>\n", argv[0]);
+		return 0;
+	}
+
+	off_t offset = 0x1b900000;
+	size_t len = atoi(argv[1]);
+	printf("phys_addr: %ld, %02x, length: %ld\n", (long int)offset,
+	       (unsigned int)offset, (long int)len);
+
+	int fd = open("/dev/mem", O_SYNC);
+	unsigned int *mem =
+	    (unsigned int *)mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_PRIVATE,
+				 fd, offset);
+
+	if (mem == NULL) {
+		printf("Can't map memory\n");
+		return -2;
+	}
+
+	// configure axis to write to memory
+	printf("config start\n");
+	cfg_write(CFG_AXIS_ADDR, 2);
+	cfg_write(CFG_AXIS_DATA, offset);
+	cfg_write(CFG_AXIS_DATA, len);
+	printf("config done\n");
+
+	// send data to be written over cfg bus
+	printf("write start\n");
+	for (i = 0; i < len; ++i) {
+		cfg_write(CFG_HP0_DST_DATA, i + 1);
+		//cfg_write(CFG_HP0_DST_DATA, 0);
+	}
+	printf("hp0 dst cnt: %d\n", cfg_read(CFG_HP0_DST_CNT));
+	printf("write done\n");
+
+	// check memory for data
+	for (i = 0; i < len; ++i) {
+		printf("%6d, %10ld, %02x, hex: %x,\tbinary: %d\n", i + 1,
+		       (offset + (sizeof(mem[0]) * i)),
+		       (unsigned int)(offset + (sizeof(mem[0]) * i)),
+		       (int)mem[i], (int)mem[i]);
+	}
+
+	if (munmap(mem, len) < 0) {
+		printf("Can't unmap memory\n");
+		return -3;
+	}
+
+	if (axis_exit() != 0) {
+		return -1;
+	}
+
+	printf("\ndone\n");
+
+	return 0;
+}