Automatic software update from TFTP server

The auto-update feature allows to automatically download software updates
from a TFTP server and store them in Flash memory during boot. Updates are
contained in a FIT file and protected with SHA-1 checksum.

More detailed description can be found in doc/README.update.
Signed-off-by: Rafal Czubak <rcz@semihalf.com>
Signed-off-by: Bartlomiej Sieka <tur@semihalf.com>

README

@@ -1740,6 +1740,14 @@ The following options need to be configured:
 		example, some LED's) on your board. At the moment,
 		the following checkpoints are implemented:
 
+- Automatic software updates via TFTP server
+		CONFIG_UPDATE_TFTP
+		CONFIG_UPDATE_TFTP_CNT_MAX
+		CONFIG_UPDATE_TFTP_MSEC_MAX
+
+		These options enable and control the auto-update feature;
+		for a more detailed description refer to doc/README.update.
+
 Legacy uImage format:
 
   Arg	Where			When
@@ -2814,6 +2822,10 @@ Some configuration options can be set using Environment Variables:
 		  allowed for use by the bootm command. See also "bootm_low"
 		  environment variable.
 
+  updatefile	- Location of the software update file on a TFTP server, used
+		  by the automatic software update feature. Please refer to
+		  documentation in doc/README.update for more details.
+
   autoload	- if set to "no" (any string beginning with 'n'),
 		  "bootp" will just load perform a lookup of the
 		  configuration from the BOOTP server, but not try to

common/Makefile

@@ -153,6 +153,7 @@ COBJS-y += flash.o
 COBJS-y += kgdb.o
 COBJS-$(CONFIG_LCD) += lcd.o
 COBJS-$(CONFIG_LYNXKDI) += lynxkdi.o
+COBJS-$(CONFIG_UPDATE_TFTP) += update.o
 COBJS-$(CONFIG_USB_KEYBOARD) += usb_kbd.o
 COBJS-$(CONFIG_DDR_SPD) += ddr_spd.o
 

common/main.c

@@ -56,6 +56,9 @@ extern int do_reset (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);		/* fo
 
 extern int do_bootd (cmd_tbl_t *cmdtp, int flag, int argc, char *argv[]);
 
+#if defined(CONFIG_UPDATE_TFTP)
+void update_tftp (void);
+#endif /* CONFIG_UPDATE_TFTP */
 
 #define MAX_DELAY_STOP_STR 32
 
@@ -301,6 +304,10 @@ void main_loop (void)
 	trab_vfd (bmp);
 #endif	/* CONFIG_VFD && VFD_TEST_LOGO */
 
+#if defined(CONFIG_UPDATE_TFTP)
+	update_tftp ();
+#endif /* CONFIG_UPDATE_TFTP */
+
 #ifdef CONFIG_BOOTCOUNT_LIMIT
 	bootcount = bootcount_load();
 	bootcount++;

common/update.c

+/*
+ * (C) Copyright 2008 Semihalf
+ *
+ * Written by: Rafal Czubak <rcz@semihalf.com>
+ *             Bartlomiej Sieka <tur@semihalf.com>
+ *
+ * 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>
+
+#if !(defined(CONFIG_FIT) && defined(CONFIG_OF_LIBFDT))
+#error "CONFIG_FIT and CONFIG_OF_LIBFDT are required for auto-update feature"
+#endif
+
+#if defined(CFG_NO_FLASH)
+#error "CFG_NO_FLASH defined, but FLASH is required for auto-update feature"
+#endif
+
+#include <command.h>
+#include <flash.h>
+#include <net.h>
+#include <malloc.h>
+
+/* env variable holding the location of the update file */
+#define UPDATE_FILE_ENV		"updatefile"
+
+/* set configuration defaults if needed */
+#ifndef CONFIG_UPDATE_LOAD_ADDR
+#define CONFIG_UPDATE_LOAD_ADDR	0x100000
+#endif
+
+#ifndef CONFIG_UPDATE_TFTP_MSEC_MAX
+#define CONFIG_UPDATE_TFTP_MSEC_MAX	100
+#endif
+
+#ifndef CONFIG_UPDATE_TFTP_CNT_MAX
+#define CONFIG_UPDATE_TFTP_CNT_MAX	0
+#endif
+
+extern ulong TftpRRQTimeoutMSecs;
+extern int TftpRRQTimeoutCountMax;
+extern flash_info_t flash_info[];
+extern ulong load_addr;
+
+static uchar *saved_prot_info;
+
+static int update_load(char *filename, ulong msec_max, int cnt_max, ulong addr)
+{
+	int size, rv;
+	ulong saved_timeout_msecs;
+	int saved_timeout_count;
+	char *saved_netretry, *saved_bootfile;
+
+	rv = 0;
+	/* save used globals and env variable */
+	saved_timeout_msecs = TftpRRQTimeoutMSecs;
+	saved_timeout_count = TftpRRQTimeoutCountMax;
+	saved_netretry = strdup(getenv("netretry"));
+	saved_bootfile = strdup(BootFile);
+
+	/* set timeouts for auto-update */
+	TftpRRQTimeoutMSecs = msec_max;
+	TftpRRQTimeoutCountMax = cnt_max;
+
+	/* we don't want to retry the connection if errors occur */
+	setenv("netretry", "no");
+
+	/* download the update file */
+	load_addr = addr;
+	copy_filename(BootFile, filename, sizeof(BootFile));
+	size = NetLoop(TFTP);
+
+	if (size < 0)
+		rv = 1;
+	else if (size > 0)
+		flush_cache(addr, size);
+
+	/* restore changed globals and env variable */
+	TftpRRQTimeoutMSecs = saved_timeout_msecs;
+	TftpRRQTimeoutCountMax = saved_timeout_count;
+
+	setenv("netretry", saved_netretry);
+	if (saved_netretry != NULL)
+		free(saved_netretry);
+
+	if (saved_bootfile != NULL) {
+		copy_filename(BootFile, saved_bootfile, sizeof(BootFile));
+		free(saved_bootfile);
+	}
+
+	return rv;
+}
+
+static int update_flash_protect(int prot, ulong addr_first, ulong addr_last)
+{
+	uchar *sp_info_ptr;
+	ulong s;
+	int i, bank, cnt;
+	flash_info_t *info;
+
+	sp_info_ptr = NULL;
+
+	if (prot == 0) {
+		saved_prot_info =
+			calloc(CFG_MAX_FLASH_BANKS * CFG_MAX_FLASH_SECT, 1);
+		if (!saved_prot_info)
+			return 1;
+	}
+
+	for (bank = 0; bank < CFG_MAX_FLASH_BANKS; ++bank) {
+		cnt = 0;
+		info = &flash_info[bank];
+
+		/* Nothing to do if the bank doesn't exist */
+		if (info->sector_count == 0)
+			return 0;
+
+		/* Point to current bank protection information */
+		sp_info_ptr = saved_prot_info + (bank * CFG_MAX_FLASH_SECT);
+
+		/*
+		 * Adjust addr_first or addr_last if we are on bank boundary.
+		 * Address space between banks must be continuous for other
+		 * flash functions (like flash_sect_erase or flash_write) to
+		 * succeed. Banks must also be numbered in correct order,
+		 * according to increasing addresses.
+		 */
+		if (addr_last > info->start[0] + info->size - 1)
+			addr_last = info->start[0] + info->size - 1;
+		if (addr_first < info->start[0])
+			addr_first = info->start[0];
+
+		for (i = 0; i < info->sector_count; i++) {
+			/* Save current information about protected sectors */
+			if (prot == 0) {
+				s = info->start[i];
+				if ((s >= addr_first) && (s <= addr_last))
+					sp_info_ptr[i] = info->protect[i];
+
+			}
+
+			/* Protect/unprotect sectors */
+			if (sp_info_ptr[i] == 1) {
+#if defined(CFG_FLASH_PROTECTION)
+				if (flash_real_protect(info, i, prot))
+					return 1;
+#else
+				info->protect[i] = prot;
+#endif
+				cnt++;
+			}
+		}
+
+		if (cnt) {
+			printf("%sProtected %d sectors\n",
+						prot ? "": "Un-", cnt);
+		}
+	}
+
+	if((prot == 1) && saved_prot_info)
+		free(saved_prot_info);
+
+	return 0;
+}
+
+static int update_flash(ulong addr_source, ulong addr_first, ulong size)
+{
+	ulong addr_last = addr_first + size - 1;
+
+	/* round last address to the sector boundary */
+	if (flash_sect_roundb(&addr_last) > 0)
+		return 1;
+
+	if (addr_first >= addr_last) {
+		printf("Error: end address exceeds addressing space\n");
+		return 1;
+	}
+
+	/* remove protection on processed sectors */
+	if (update_flash_protect(0, addr_first, addr_last) > 0) {
+		printf("Error: could not unprotect flash sectors\n");
+		return 1;
+	}
+
+	printf("Erasing 0x%08lx - 0x%08lx", addr_first, addr_last);
+	if (flash_sect_erase(addr_first, addr_last) > 0) {
+		printf("Error: could not erase flash\n");
+		return 1;
+	}
+
+	printf("Copying to flash...");
+	if (flash_write((char *)addr_source, addr_first, size) > 0) {
+		printf("Error: could not copy to flash\n");
+		return 1;
+	}
+	printf("done\n");
+
+	/* enable protection on processed sectors */
+	if (update_flash_protect(1, addr_first, addr_last) > 0) {
+		printf("Error: could not protect flash sectors\n");
+		return 1;
+	}
+
+	return 0;
+}
+
+static int update_fit_getparams(const void *fit, int noffset, ulong *addr,
+						ulong *fladdr, ulong *size)
+{
+	const void *data;
+
+	if (fit_image_get_data(fit, noffset, &data, (size_t *)size))
+		return 1;
+
+	if (fit_image_get_load(fit, noffset, (ulong *)fladdr))
+		return 1;
+
+	*addr = (ulong)data;
+
+	return 0;
+}
+
+void update_tftp(void)
+{
+	char *filename, *env_addr;
+	int images_noffset, ndepth, noffset;
+	ulong update_addr, update_fladdr, update_size;
+	ulong addr;
+	void *fit;
+
+	printf("Auto-update from TFTP: ");
+
+	/* get the file name of the update file */
+	filename = getenv(UPDATE_FILE_ENV);
+	if (filename == NULL) {
+		printf("failed, env. variable '%s' not found\n",
+							UPDATE_FILE_ENV);
+		return;
+	}
+
+	printf("trying update file '%s'\n", filename);
+
+	/* get load address of downloaded update file */
+	if ((env_addr = getenv("loadaddr")) != NULL)
+		addr = simple_strtoul(env_addr, NULL, 16);
+	else
+		addr = CONFIG_UPDATE_LOAD_ADDR;
+
+
+	if (update_load(filename, CONFIG_UPDATE_TFTP_MSEC_MAX,
+					CONFIG_UPDATE_TFTP_CNT_MAX, addr)) {
+		printf("Can't load update file, aborting auto-update\n");
+		return;
+	}
+
+	fit = (void *)addr;
+
+	if (!fit_check_format((void *)fit)) {
+		printf("Bad FIT format of the update file, aborting "
+							"auto-update\n");
+		return;
+	}
+
+	/* process updates */
+	images_noffset = fdt_path_offset(fit, FIT_IMAGES_PATH);
+
+	ndepth = 0;
+	noffset = fdt_next_node(fit, images_noffset, &ndepth);
+	while (noffset >= 0 && ndepth > 0) {
+		if (ndepth != 1)
+			goto next_node;
+
+		printf("Processing update '%s' :",
+			fit_get_name(fit, noffset, NULL));
+
+		if (!fit_image_check_hashes(fit, noffset)) {
+			printf("Error: invalid update hash, aborting\n");
+			goto next_node;
+		}
+
+		printf("\n");
+		if (update_fit_getparams(fit, noffset, &update_addr,
+					&update_fladdr, &update_size)) {
+			printf("Error: can't get update parameteres, "
+								"aborting\n");
+			goto next_node;
+		}
+		if (update_flash(update_addr, update_fladdr, update_size)) {
+			printf("Error: can't flash update, aborting\n");
+			goto next_node;
+		}
+next_node:
+		noffset = fdt_next_node(fit, noffset, &ndepth);
+	}
+
+	return;
+}

doc/README.update

+Automatic software update from a TFTP server
+============================================
+
+Overview
+--------
+
+This feature allows to automatically store software updates present on a TFTP
+server in NOR Flash. In more detail: a TFTP transfer of a file given in
+environment variable 'updatefile' from server 'serverip' is attempted during
+boot. The update file should be a FIT file, and can contain one or more
+updates. Each update in the update file has an address in NOR Flash where it
+should be placed, updates are also protected with a SHA-1 checksum. If the
+TFTP transfer is successful, the hash of each update is verified, and if the
+verification is positive, the update is stored in Flash.
+
+The auto-update feature is enabled by the CONFIG_UPDATE_TFTP macro:
+
+#define CONFIG_UPDATE_TFTP		1
+
+
+Note that when enabling auto-update, Flash support must be turned on.  Also,
+one must enable FIT and LIBFDT support:
+
+#define CONFIG_FIT		1
+#define CONFIG_OF_LIBFDT	1
+
+The auto-update feature uses the following configuration knobs:
+
+- CONFIG_UPDATE_LOAD_ADDR
+
+  Normally, TFTP transfer of the update file is done to the address specified
+  in environment variable 'loadaddr'. If this variable is not present, the
+  transfer is made to the address given in CONFIG_UPDATE_LOAD_ADDR (0x100000
+  by default).
+
+- CONFIG_UPDATE_TFTP_CNT_MAX
+  CONFIG_UPDATE_TFTP_MSEC_MAX
+
+  These knobs control the timeouts during initial connection to the TFTP
+  server. Since a transfer is attempted during each boot, it is undesirable to
+  have a long delay when a TFTP server is not present.
+  CONFIG_UPDATE_TFTP_MSEC_MAX specifies the number of seconds to wait for the
+  server to respond to initial connection, and CONFIG_UPDATE_TFTP_CNT_MAX
+  gives the number of such connection retries. CONFIG_UPDATE_TFTP_CNT_MAX must
+  be non-negative and is 0 by default, CONFIG_UPDATE_TFTP_MSEC_MAX must be
+  positive and is 1 by default.
+
+Since the update file is in FIT format, it is created from an *.its file using
+the mkimage tool. dtc tool with support for binary includes, e.g. in version
+1.2.0 or later, must also be available on the system where the update file is
+to be prepared. Refer to the doc/uImage.FIT/ directory for more details on FIT
+images.
+
+
+Example .its files
+------------------
+
+- doc/uImage.FIT/update_uboot.its
+
+  A simple example that can be used to create an update file for automatically
+  replacing U-Boot image on a system.
+
+  Assuming that an U-Boot image u-boot.bin is present in the current working
+  directory, and that the address given in the 'load' property in the
+  'update_uboot.its' file is where the U-Boot is stored in Flash, the
+  following command will create the actual update file 'update_uboot.itb':
+
+  mkimage -f update_uboot.its update_uboot.itb
+
+  Place 'update_uboot.itb' on a TFTP server, for example as
+  '/tftpboot/update_uboot.itb', and set the 'updatefile' variable
+  appropriately, for example in the U-Boot prompt:
+
+  setenv updatefile /tftpboot/update_uboot.itb
+  saveenv
+
+  Now, when the system boots up and the update TFTP server specified in the
+  'serverip' environment variable is accessible, the new U-Boot image will be
+  automatically stored in Flash.
+
+  NOTE: do make sure that the 'u-boot.bin' image used to create the update
+  file is a good, working image. Also make sure that the address in Flash
+  where the update will be placed is correct. Making mistake here and
+  attempting the auto-update can render the system unusable.
+
+- doc/uImage.FIT/update3.its
+
+  An example containing three updates. It can be used to update Linux kernel,
+  ramdisk and FDT blob stored in Flash. The procedure for preparing the update
+  file is similar to the example above.

doc/uImage.FIT/update3.its

+/*
+ * Example Automatic software update file.
+ */
+/ {
+	description = "Automatic software updates: kernel, ramdisk, FDT";
+	#address-cells = <1>;
+
+	images {
+		update@1 {
+			description = "Linux kernel binary";
+			data = /incbin/("./vmlinux.bin.gz");
+			compression = "none";
+			type = "firmware";
+			load = <FF700000>;
+			hash@1 {
+				algo = "sha1";
+			};
+		};
+		update@2 {
+			description = "Ramdisk image";
+			data = /incbin/("./ramdisk_image.gz");
+			compression = "none";
+			type = "firmware";
+			load = <FF8E0000>;
+			hash@1 {
+				algo = "sha1";
+			};
+		};
+
+		update@3 {
+			description = "FDT blob";
+			data = /incbin/("./blob.fdt");
+			compression = "none";
+			type = "firmware";
+			load = <FFAC0000>;
+			hash@1 {
+				algo = "sha1";
+			};
+		};
+	};
+};

doc/uImage.FIT/update_uboot.its

+/*
+ * Automatic software update for U-Boot
+ * Make sure the flashing addresses ('load' prop) is correct for your board!
+ */
+/ {
+	description = "Automatic U-Boot update";
+	#address-cells = <1>;
+
+	images {
+		update@1 {
+			description = "U-Boot binary";
+			data = /incbin/("./u-boot.bin");
+			compression = "none";
+			type = "firmware";
+			load = <FFFC0000>;
+			hash@1 {
+				algo = "sha1";
+			};
+		};
+	};
+};