Make devmem2 less verbose.HEADmaster

This patch removes a lot of irrelevant output from devmem2
such as the virtual address, which is used to access the target
address.

In case of read operation devmem2 now just prints the read value.
In case of write operation devmem2 prints the read-back value.

Signed-off-by: Christoph Muellner <christoph.muellner@theobroma-systems.com>

1 files changed, 61 insertions, 48 deletions

diff --git a/devmem2.c b/devmem2.c
index 6003c4d..b4ecb18 100644
--- a/devmem2.c
+++ b/devmem2.c
@@ -50,26 +50,31 @@
 #include <sys/mman.h>
 #include <stdint.h>
 #include <inttypes.h>
- 
-#define FATAL do { fprintf(stderr, "Error at line %d, file %s (%d) [%s]\n", \
-  __LINE__, __FILE__, errno, strerror(errno)); exit(1); } while(0)
- 
+
+#define FATAL \
+	do { \
+		fprintf(stderr, "Error at line %d, file %s (%d) [%s]\n", \
+			__LINE__, __FILE__, errno, strerror(errno)); \
+		exit(1); \
+	} while(0)
+
 #define MAP_SIZE 4096UL
 #define MAP_MASK (MAP_SIZE - 1)
 
 int main(int argc, char **argv) {
-    int fd;
-    void *map_base, *virt_addr; 
+	int fd;
+	void *map_base, *virt_addr; 
 	uint64_t read_result, writeval;
+	int do_write = 0;
 	off_t target;
 	int access_type = 'w';
-	
+
 	if(argc < 2) {
 		fprintf(stderr, "\nUsage:\t%s { address } [ type [ data ] ]\n"
-			"\taddress : memory address to act upon\n"
-			"\ttype    : access operation type : [b]yte, [h]alfword, [w]ord, [d]oubleword\n"
-			"\tdata    : data to be written\n\n",
-			argv[0]);
+				"\taddress : memory address to act upon\n"
+				"\ttype    : access operation type : [b]yte, [h]alfword, [w]ord, [d]oubleword\n"
+				"\tdata    : data to be written\n\n",
+				argv[0]);
 		exit(1);
 	}
 	target = strtoull(argv[1], 0, 0);
@@ -77,41 +82,44 @@ int main(int argc, char **argv) {
 	if(argc > 2)
 		access_type = tolower(argv[2][0]);
 
+	if (argc > 3) {
+		writeval = strtoul(argv[3], 0, 0);
+		do_write = 1;
+	}
 
-    if((fd = open("/dev/mem", O_RDWR | O_SYNC)) == -1) FATAL;
-    printf("/dev/mem opened.\n"); 
-    fflush(stdout);
-    
-    /* Map one page */
-    map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, target & ~MAP_MASK);
-    if(map_base == (void *) -1) FATAL;
-    printf("Memory mapped at address %p.\n", map_base); 
-    fflush(stdout);
-    
-    virt_addr = map_base + (target & MAP_MASK);
-    switch(access_type) {
-		case 'b':
-			read_result = *((uint8_t *) virt_addr);
-			break;
-		case 'h':
-			read_result = *((uint16_t *) virt_addr);
-			break;
-		case 'w':
-			read_result = *((uint32_t *) virt_addr);
-			break;
-                case 'd':
-                        read_result = *((uint64_t *) virt_addr);
-                        break;
 
-		default:
-			fprintf(stderr, "Illegal data type '%c'.\n", access_type);
-			exit(2);
-	}
-    printf("Value at address 0x%X (%p): 0x%" PRIX64 "\n", target, virt_addr, read_result); 
-    fflush(stdout);
+	if((fd = open("/dev/mem", O_RDWR | O_SYNC)) == -1)
+		FATAL;
 
-	if(argc > 3) {
-		writeval = strtoul(argv[3], 0, 0);
+	/* Map one page */
+	map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, target & ~MAP_MASK);
+	if(map_base == (void *) -1)
+		FATAL;
+
+	virt_addr = map_base + (target & MAP_MASK);
+
+	if (!do_write) {
+		switch(access_type) {
+			case 'b':
+				read_result = *((uint8_t *) virt_addr);
+				break;
+			case 'h':
+				read_result = *((uint16_t *) virt_addr);
+				break;
+			case 'w':
+				read_result = *((uint32_t *) virt_addr);
+				break;
+			case 'd':
+				read_result = *((uint64_t *) virt_addr);
+				break;
+			default:
+				fprintf(stderr, "Illegal data type '%c'.\n", access_type);
+				exit(2);
+		}
+
+		printf("0x%" PRIX64 "\n", read_result); 
+		fflush(stdout);
+	} else {
 		switch(access_type) {
 			case 'b':
 				*((uint8_t *) virt_addr) = writeval;
@@ -129,12 +137,17 @@ int main(int argc, char **argv) {
 				*((uint64_t *) virt_addr) = writeval;
 				read_result = *((uint64_t *) virt_addr);
 				break;
+			default:
+				fprintf(stderr, "Illegal data type '%c'.\n", access_type);
+				exit(2);
 		}
-		printf("Written 0x%X; readback 0x%X\n", writeval, read_result); 
+		printf("0x%" PRIX64 "\n", read_result); 
 		fflush(stdout);
 	}
-	
-	if(munmap(map_base, MAP_SIZE) == -1) FATAL;
-    close(fd);
-    return 0;
+
+	if(munmap(map_base, MAP_SIZE) == -1)
+		FATAL;
+	close(fd);
+
+	return 0;
 }