cmd_time: add time command

The 'time' command runs and reports execution time of commands.

Sample usage:
--------------------
u-boot# time crc 0x1000 1000
CRC32 for 00001000 ... 00001fff ==> ae94dc4b

time: 0.004 seconds, 4 ticks
--------------------

Signed-off-by: Che-Liang Chiou <clchiou@chromium.org>
Acked-by: Mike Frysinger <vapier@gentoo.org>

README

@@ -783,6 +783,7 @@ The following options need to be configured:
 		CONFIG_CMD_SOURCE	  "source" command Support
 		CONFIG_CMD_SPI		* SPI serial bus support
 		CONFIG_CMD_TFTPSRV	* TFTP transfer in server mode
+		CONFIG_CMD_TIME		* run command and report execution time
 		CONFIG_CMD_USB		* USB support
 		CONFIG_CMD_CDP		* Cisco Discover Protocol support
 		CONFIG_CMD_FSL		* Microblaze FSL support

common/Makefile

@@ -147,6 +147,7 @@ COBJS-$(CONFIG_CMD_SPI) += cmd_spi.o
 COBJS-$(CONFIG_CMD_SPIBOOTLDR) += cmd_spibootldr.o
 COBJS-$(CONFIG_CMD_STRINGS) += cmd_strings.o
 COBJS-$(CONFIG_CMD_TERMINAL) += cmd_terminal.o
+COBJS-$(CONFIG_CMD_TIME) += cmd_time.o
 COBJS-$(CONFIG_SYS_HUSH_PARSER) += cmd_test.o
 COBJS-$(CONFIG_CMD_TSI148) += cmd_tsi148.o
 COBJS-$(CONFIG_CMD_UBI) += cmd_ubi.o

common/cmd_time.c

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 2011 The Chromium OS Authors.
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <command.h>
+
+/*
+ * TODO(clchiou): This function actually minics the bottom-half of the
+ * run_command() function.  Since this function has ARM-dependent timer
+ * codes, we cannot merge it with the run_command() for now.
+ */
+static int run_command_and_time_it(int flag, int argc, char * const argv[],
+		ulong *cycles)
+{
+	cmd_tbl_t *cmdtp = find_cmd(argv[0]);
+	int retval = 0;
+
+	if (!cmdtp) {
+		printf("%s: command not found\n", argv[0]);
+		return 1;
+	}
+	if (argc > cmdtp->maxargs)
+		return cmd_usage(cmdtp);
+
+	/*
+	 * TODO(clchiou): get_timer_masked() is only defined in certain ARM
+	 * boards.  We could use the new timer API that Graeme is proposing
+	 * so that this piece of code would be arch-independent.
+	 */
+	*cycles = get_timer_masked();
+	retval = cmdtp->cmd(cmdtp, flag, argc, argv);
+	*cycles = get_timer_masked() - *cycles;
+
+	return retval;
+}
+
+static void report_time(ulong cycles)
+{
+	ulong minutes, seconds, milliseconds;
+	ulong total_seconds, remainder;
+
+	total_seconds = cycles / CONFIG_SYS_HZ;
+	remainder = cycles % CONFIG_SYS_HZ;
+	minutes = total_seconds / 60;
+	seconds = total_seconds % 60;
+	/* approximate millisecond value */
+	milliseconds = (remainder * 1000 + CONFIG_SYS_HZ / 2) / CONFIG_SYS_HZ;
+
+	printf("\ntime:");
+	if (minutes)
+		printf(" %lu minutes,", minutes);
+	printf(" %lu.%03lu seconds, %lu ticks\n",
+			seconds, milliseconds, cycles);
+}
+
+static int do_time(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
+{
+	ulong cycles = 0;
+	int retval = 0;
+
+	if (argc == 1)
+		return cmd_usage(cmdtp);
+
+	retval = run_command_and_time_it(0, argc - 1, argv + 1, &cycles);
+	report_time(cycles);
+
+	return retval;
+}
+
+U_BOOT_CMD(time, CONFIG_SYS_MAXARGS, 0, do_time,
+		"run commands and summarize execution time",
+		"command [args...]\n");