xscom-utils: Rework getsram

Allow specifying a file on the command line to read OCC SRAM data into.
If no file is specified then we print it to stdout as text. This is a
bit inconsistent, but it retains compatibility with the existing tool.

Signed-off-by: Oliver O'Halloran <oohall@gmail.com>
Signed-off-by: Stewart Smith <stewart@linux.ibm.com>

external/xscom-utils/getsram.c

@@ -26,31 +26,38 @@
 
 static void print_usage(int code)
 {
-	printf("usage: getsram [-c|--chip chip-id] addr\n");
-	printf("               [--occ-channel|n <chan>]\n");
-	printf("       getsram -v|--version\n");
+	printf("usage: getsram [opts] addr\n");
+	printf("	-c|--chip <chip-id>\n");
+	printf("	-l|--length <size to read>\n");
+	printf("        -n|--occ-channel <chan>\n");
+	printf("	-f|--file <filename>\n");
+	printf("        -v|--version\n");
 	exit(code);
 }
 
 extern const char version[];
 
 int main(int argc, char *argv[])
 {
-	uint64_t val, addr = -1ull;
+	uint64_t val, addr = -1ull, length = 8;
 	uint32_t def_chip, chip_id = 0xffffffff;
 	int rc;
 	int occ_channel = 0;
+	char *filename = NULL;
+	FILE *f = stdout;
 
 	while(1) {
 		static struct option long_opts[] = {
 			{"chip",	required_argument,	NULL,	'c'},
 			{"occ-channel",	required_argument,	NULL,	'n'},
 			{"help",	no_argument,		NULL,	'h'},
 			{"version",	no_argument,		NULL,	'v'},
+			{"length",	required_argument,	NULL,	'l'},
+			{"file",	required_argument,	NULL,	'f'},
 		};
 		int c, oidx = 0;
 
-		c = getopt_long(argc, argv, "-c:n:hlv", long_opts, &oidx);
+		c = getopt_long(argc, argv, "-c:n:hl:vf:", long_opts, &oidx);
 		if (c == EOF)
 			break;
 		switch(c) {
@@ -73,6 +80,13 @@ int main(int argc, char *argv[])
 		case 'v':
 			printf("xscom utils version %s\n", version);
 			exit(0);
+		case 'f':
+			filename = optarg;
+			break;
+		case 'l':
+			length = strtoul(optarg, NULL, 0);
+			length = (length + 7) & ~0x7; /* round up to an eight byte interval */
+			break;
 		default:
 			exit(1);
 		}
@@ -91,11 +105,37 @@ int main(int argc, char *argv[])
 	if (chip_id == 0xffffffff)
 		chip_id = def_chip;
 
-	rc = sram_read(chip_id, occ_channel, addr, &val);
+	if (filename) {
+		f = fopen(filename, "wb");
+		if (!f) {
+			fprintf(stderr, "unable to open %s for writing\n", filename);
+			exit(1);
+		}
+	}
+
+	rc = 0;
+	while (length) {
+		rc = sram_read(chip_id, occ_channel, addr, &val);
+		if (rc)
+			break;
+
+		if (f) {
+			int i;
+
+			/* make sure we write it out big endian */
+			for (i = 1; i <= 8; i++)
+				fputc((val >> (64 - i * 8)) & 0xff, f);
+		} else {
+			printf("OCC%d: %" PRIx64 "\n", occ_channel, val);
+		}
+
+		length -= 8;
+		addr += 8;
+	}
+
 	if (rc) {
 		fprintf(stderr,"Error %d reading XSCOM\n", rc);
 		exit(1);
 	}
-	printf("OCC%d: %" PRIx64 "\n", occ_channel, val);
 	return 0;
 }