log: Add a command to control the log output format

Add a 'log format' command which can display or change the log output
format. This is useful for changing how much information is displayed. The
ordering of the fields is fixed.

Signed-off-by: Simon Glass <sjg@chromium.org>

cmd/log.c

@@ -10,6 +10,8 @@
 #include <dm.h>
 #include <log.h>
 
+static char log_fmt_chars[LOGF_COUNT] = "clFLfm";
+
 static int do_log_level(cmd_tbl_t *cmdtp, int flag, int argc,
 			char * const argv[])
 {
@@ -21,11 +23,48 @@ static int do_log_level(cmd_tbl_t *cmdtp, int flag, int argc,
 	return 0;
 }
 
+static int do_log_format(cmd_tbl_t *cmdtp, int flag, int argc,
+			 char * const argv[])
+{
+	int i;
+
+	if (argc > 1) {
+		const char *str = argv[1];
+
+		if (!strcmp(str, "default")) {
+			gd->log_fmt = LOGF_DEFAULT;
+		} else if (!strcmp(str, "all")) {
+			gd->log_fmt = LOGF_ALL;
+		} else {
+			gd->log_fmt = 0;
+			for (; *str; str++) {
+				char *ptr = strchr(log_fmt_chars, *str);
+
+				if (!ptr) {
+					printf("Invalid log char '%c'\n", *str);
+					return CMD_RET_FAILURE;
+				}
+				gd->log_fmt |= 1 << (ptr - log_fmt_chars);
+			}
+		}
+	} else {
+		printf("Log format: ");
+		for (i = 0; i < LOGF_COUNT; i++) {
+			if (gd->log_fmt & (1 << i))
+				printf("%c", log_fmt_chars[i]);
+		}
+		printf("\n");
+	}
+
+	return 0;
+}
+
 static cmd_tbl_t log_sub[] = {
 	U_BOOT_CMD_MKENT(level, CONFIG_SYS_MAXARGS, 1, do_log_level, "", ""),
 #ifdef CONFIG_LOG_TEST
 	U_BOOT_CMD_MKENT(test, 2, 1, do_log_test, "", ""),
 #endif
+	U_BOOT_CMD_MKENT(format, CONFIG_SYS_MAXARGS, 1, do_log_format, "", ""),
 };
 
 static int do_log(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
@@ -52,6 +91,10 @@ static char log_help_text[] =
 #ifdef CONFIG_LOG_TEST
 	"log test - run log tests\n"
 #endif
+	"log format <fmt> - set log output format. <fmt> is a string where\n"
+	"\teach letter indicates something that should be displayed:\n"
+	"\tc=category, l=level, F=file, L=line number, f=function, m=msg\n"
+	"\tor 'default', equivalent to 'fm', or 'all' for all"
 	;
 #endif